Skyting

[Tad Eareckson]

1984/10
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SKYTING NO.30
OCT. 1984
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1984/10-01

TOWING BY TRIKE

Reviewed by Donnell Hewett

Some time ago Bob Fisher (of Houston, Texas) sent me an article from the May 1984 issue of WINGS (the English Hang Gliding publication). It has taken me this long to get around to reporting what was contained in that article. This is that report.

The original author, Dave Simpson, gave a detailed account of his system of aerotowing hang gliders prior to the CAA ban on aerotowing. Yes, it seems that someone wrote a letter to the English equivalent of the FAA which "resulted in the very predictable reaction that the CAA chose to interpret the ANO as not permitting microlight aerotowing". (Sounds like the U.S.A. does not have a monopoly on "restricted" thinkers.)

Dave's system is somewhat similar to that of Thevenot's (SKYTING No. 24.), so I'll only describe here the major differences between their systems.

TOW BAR RELEASE

Instead of running the towline through the hollow shaft of the tug's propeller as Thevenot did, Dave mounted an L-shaped towbar to the rear of the trike as shown in Fig. 1. A Bowden cable runs from the release to the trigger located under the pilot's left foot. This way the tug pilot can keep his hands on the control bar and still release the glider in an emergency situation.

The system is designed so that if the glider climbs higher than 35 degrees above the tug, the towline will auto-release. Dave considers such an auto-release device essential to towing safety because of the dangers of glider lock-out and tug pitch-down.

Since the minimum speed of the tug exceeds the maximum comfortable speed of the glider, there is a strong tendency for the glider to try to climb too high in a type of pitch lock-out tendency. The auto-release device prevents this tendency from causing an accident by releasing the glider before it becomes a major problem.

Also, when the glider gets high, the towline pulls up on the rear of the trike, trying to force the tug into a pitch-down dive. Again the auto-release device limits this tendency.

TOWLINE

Dave says he would not use a nylon towline because of the excessive stretch. And he feels that plaited rope is better than twisted rope because under tension the latter can cause the weak links to twist and become weaker. He recommends a 180 pound weak link at the glider end and a 250 pound weak link at the tug end. (Both weak links are considered essential.)

An in line drogue chute is attached to the glider end of the towline to prevent the rope from flying forwards into the prop when released under high tension.

The full length of the towline is 90 meters (300 ft).

THE SIMPSON BRA

The towline is attached to the pilot's chest through a single point release device called a "Simpson Bra". It comprises an aluminum spreader tube with padded webbing at each end. The tube carries a central release with its trigger. The webbing passes under the pilot's armpits and fastens with a buckle between his/her shoulder blades.

According to Dave, single point body-towing like this ensures a reasonable level of protection against roll lock-out but only up to angles of about 30 degrees in the horizontal plane. While 30 degrees is a fairly large angle for a long tow rope, a crosswind take-off for a novice pilot could achieve lock-out point and - close to the ground - could be hazardous.

TRIGGER LOCATION

Two conclusions formed as a result of a towing seminar held in Germany in April 1983 were that (a) novice tow pilots should be given the option of a control bar-mounted trigger OR a body-mounted one, while (b) experienced pilots should be safe with a trigger mounted on the body but near to hand. Since the Simpson Bra was designed for experienced pilots, the trigger was located on the body.

FRENCH CONNECTION

Dave has towed both with and without the French Connection. Without the Connection, it was hard to handle the Magic 150 glider, but with it no control problems were encountered. Through experience, Dave found that without the French Connection the glider needed to be trimmed fast to be comfortable on tow, while after release, it needed to be trimmed back to minimum sink. The two stages were incompatible, but the French Connection removed that incompatibility.

TAKE-OFF TECHNIQUE

The Simpson Bra is fitted after the harness is put on and the straps go under the harness shoulder supports. There is a tendency for the harness to ride up when the line pulls horizontally in prone. For this reason "a stirrup rubber is advisable because getting into prone early puts you fully in control early and makes for an easier tow."

Dave follows the practice of hooking in before attaching the towline (an important safety practice in towing). He uses a signal man at take-off to relay messages from glider to tug. The signals are "take up slack" and "all out".

Once airborne the glider pilot should stay as low as possible until the tug lifts off. Otherwise his line may grow slack when the tug suddenly starts climbing. The tug pilot should "fly as if he has an egg on the king post." All attitude changes (particularly during take-off) should be small and initiated smoothly.

CLIMB OUT

Dave recommends that the glider pilot control the climb out angle and rate. This is accomplished as follows: If the glider is too low, slowing up produces a glide climb and an increase in line tension. This reduces the tug's available thrust and decreases its climb rate. In short, the glider pilot simply keeps the glider positioned level with the tug, and everything else works out fine.

If the glider flies into the propwash of the tug, the pilot should slow down and climb out as soon as possible. He should not pull in as he normally would when encountering other types of severe turbulence.

TURNS

Dave says, "Turns can be tricky if you don't start under the right conditions." (And if you don't believe this, see Dave Garrison's accident report in SKYTING No. 29.) Dave Simpson notes two potential problems:

(1) The line tension can affect the tug, causing it to sideslip in the turn. It can even cause the tug to drop so rapidly that the only recourse is to release the glider from tow. This side force is zero only when the tow rope is directly in line with the keel. Obviously the glider pilot should try to keep it this way. However, this is possible only if the tug turns very gently as shown in Fig. 2.

(2) The other problem associated with turns can also be seen from Fig. 2. Since the glider must fly a longer path than the tug, the glider's air speed must increase. Thus, if he enters the turn too high and with too much air speed, he can experience a lock-out. "The way to avoid this problem is to start low, turn a little in the opposite direction before the tug turns, increase speed in anticipation and then follow round. It is very much a matter of positioning the glider in the correct point in space and keeping it there, and a certain amount of skill and anticipation is required if the glider is to avoid going round like a 50p piece."

Both of these problems are avoided by the glider being in the right place at the initiation of the turn, and keeping the turn on a very large radius.

THE RELEASE

The release flight pattern should be planned. The glider should not release too high (lest the towline auto-release from the tug), and the tug should turn opposite the glider. If the glider releases unexpectedly, the tug will rapidly climb while the glider descends into its prop wash. Even if the glider tries to turn away, he may still catch a wing in the prop wash. So a coordinated release is better than just popping off.

PERFORMANCE

Dave made some performance measurements on his system on a cold (4 C) day and obtained the following values (+/- 10%):

Tug static thrust
- 265 lb
Thrust fall off (at 28 mph)
- 20%
Climb rate on tow
- 340 fpm
Take-off distance (from rear of glider to tug rotation point)
- 160 meters
Tug Gross Weight
- 440 lb
Glider Gross Weight
- 265 lb
L/D tug
- 6:1
L/D glider (150 Magic)
- 7:1

(Note: The glider's maximum L/D is much better than this but occurrs at a slower speed than that required for aerotowing.)

It was also noticed that a 10% reduction in tug weight produced a surprisingly large 15% increase in climb rate, so weight IS important.

COST

Dave disagrees with Thevenot when he claims that aerotowing hang gliders is cost-restrictive. Dave feels that aerotowing can be cost effective if a group of eight to ten pilots share their expenses - possibly in some type of aerotow club. After all, not everyone will be wanting to fly at the same time, and costs can be distributed according to use by charging tow fees on each flight.

GLIDER PILOT ABILITY

Dave says, "At present I don't see the system ever being suitable for solo pilots of less than, say, five hours experience. That is not to say that a dual glider is out of the question - we simply need a lighter more powerful tug." He feels that a "raw P1" has not yet developed instincts or become sufficiently comfortable aloft to allow his mind to make correct decisions under the demanding conditions of aerotowing.

UPDATE

Dave was planning to demonstrate his system to those interested when the CAA clampdown occurred. Since this all happened about 6 months ago, I do not know the current situation. I hope things have improved by now so that continued progress can be made in English aerotowing.
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Fig. 1. Dave Simpson's Aerotow System.
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Fig. 2. Towing turns.

090m
150m
300m
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WING STABILITY
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1984/10-02

Dear Donnell,

In SKYTING No. 1, Part 3, you say, "The reason that the center of lift has moved rearward is because the angle of attack increased as the control bar was pushed forward."

This statement seem to be in direct contridiction to what Dennis Pagen says in "Hang Gliding and Flying Skills, page 17: "In general the center of pressure will move forward as the angle of attack increases and back as the angle decreases."

Could you clear this up.?

I enjoy your newsletter very much an am in the process of constructing a skyting system.

Mark Tracy
Las Vegas, NV
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1984/10-03

Dear Mark,

You asked me to clarify the apparent contridiction between what I said in SKYTING No. 1 and what Dennis Pagen said in his book concerning the movement of the center of lift as the angle of attack increases. The difference is that Dennis was referring to an UNSTABLE wing of constant profile and zero sweep, while I was referring to a STABLE wing platform like those used in all modern hang gliders.

Refer back to Pagen's book on page 17 under Figure 18 where he points out that the wing he is considering is, "Not exactly a desirable state of affairs! The truth is, all airfoils as we have pictured them have this unwanted trait called divergence or instability." He then goes on to describe several ways to overcome this instability problem, including reflex, wing twist, dihedral, etc. And on page 18 he says, "A design is not safe if it is not stable."

What this means is that ALL safe hang gliders have STABLE wing platforms and, therefore, behave as a unit opposite to that of the unstable wing he describes on page 17. In other words, any airworthy hang glider (using a stable wing platform) will have its center of lift move rearward as the angle of attack increases, and vice versi. This is the situation I was describing in SKYTING No. 1

Donnell
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1984/10-04

SKYTING SETS NEW XC RECORD IN ISRAEL

I'd like to share with you an important news item from our activity here in Nahal Oz.

Saturday 18.8.84 12:30 pm, the wind was west 7 kmh. We used 600 m rope. The pilot was Aron Sagie (a member in the committee to test skyting). He launched and entered a strong thermal at 250 m altitude higher than he released. He landed after 3:20 hours in Sodom (100 km from Nahal Oz).

This flight is the longest that has been done in Israel. Normally we used to fly in the north of the country, where there are mountains. Because of a few limits we have here in Israel, the longest flight till now was about 60 km. One of the problems is the border in the east with "not so" friendly neighbors. In center, south of Israel, where Nahal Oz is located, the country is wider (no mountains to take off). Usually the winds are west and the flights for cross country are to east. Now by using the skyting technique we'll open new possibilities for our hang gliding pilots.

We (the committee) didn't finish testing the system yet. I hope it will be soon.

Heber Itzhak
Nachal Oz
ISRAEL
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1984/10-05

THREADED BRIDLE PROBLEM

Dear Donnell,

It's been a while! A quick note to let you know the latest. The threaded bridle's habit of hanging up on the body ring is INDEED a PROBLEM! I have noticed this getting worse as the 3/16" Sampson type yachting line is wearing. I plan to try replacing it with other lengths and sizes of line to see if there is a solution.

In the meanwhile DON'T throw away your three-rings anyone! If you are using a threaded bridle, run a biner as your body ring. It is much safer than a knife to release a body ring hang-up, but keep the hook knife handy!

Please put me on the record as a concerned fellow flyer. I have no business affiliations with ANY hang gliding company or product. My letters to you are intended to convey ONLY my experiences and thoughts in the open letter format you provide for the world flying community. Lisa and I have had many fantastic skyting days, thanks to you and the forum you have given all of us. I therefore hope MORE people will let you know what's going on so lives or equipment won't be damaged repeating mistakes.

I have no details, but I have heard of ONE FATAL (Tucson) and two serious towing accidents in Arizona since our move here in June. (Ed: I hope you are referring to the Arizona fatality mentioned in #29 and not another one I haven't heard of. And you people who know about these and other towing accidents, PLEASE let us know. YOU MAY BE SAVING A LIFE!) Totally senseless considering how SAFE it can be with experienced crews. I hope local AZ pilots will continue to share their information so we can fly SAFELY. We need good news AND bad to be informed completely.

Speaking of good news, we had fun to day learning to use a payout reel. We need to work out a few bugs but so far it's great!

How about you Florida pilots? I wish a Cypress Gardens pilot would let us know how they use their lines to get high. That Joe Grebo ((Greblo)) dude flys good. I wonder what his tricks are?

I could go on but I'll wait until my post skyout grin is gone from today's SKYTING.

Like that birdman in WASHINGTON says, "Keep turnin' circles!"

Lisa and Joe Sztukowski
Phoenix, AZ
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SKYTING IN ENGLAND
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1984/10-06

Dear Donnell,

May I begin with some statistics? We have just reviewed our flight logs and have painstakingly calculated that we have had 12 hours and 5 minutes of towing since the middle of February. This amounts to 876 tows logged (in excess of 1000 with the previous tows which were performed before we began recording everything in detail).

BUGGY WHEEL LAUNCH

This record is in effect low compared to a group in BUDAPEST UNIVERSITY. I have yet to make contact with them, but I have been told that they have had some 3000 flights and gained incredible heights. The name is Ference Kiss, M.M.R.K. Budapest University. They say the pilot is launched in prone with a set of buggy wheels which he drops when he is flying high enough. Novel I must say, but it does sound feasible.

PAY OUT WNINCH

Change of subject, the payout winch we have now will be available to order. The fee would be $2000.00, shipping included. The standard of workmanship necessary to build (homebuild) as winch would be very high. However, if one should wish to try, a lesser performance "pay out" could be built using an auto disk brake system mounted on a frame carrying the spool with electric starter motor as a rewind mechanism.

The payout system has many obvious advantages:

1. We only have to pay out the stretcher. Therefore winch man and pilot stay in closer contact.

2. The driver is relieved of the responsibility of correct line tension while driving the auto.

3. The winch man has more positive control on the important factors like line release and height gain factors.

4. There is a much faster turn around of flights.

5. The line lasts longer due to less dragged trips. (The line is 50% rewound before the drogue chute drops to the ground.)

6. Reduced snagging on trees and obstructions.

WEAK LINK BREAKS

The subject of low altitude breaks is still with us. The take off on low tension is good but if we do our sums, a 70 lb pull with the pilot pulling on a little extra speed before he gently rotates to make his or her steady and carefull climb through wind gradient to safety at 50+ ft can in effect generate high energy in the aircraft. When subject to gusting the aircraft can convert this energy into shock loading on the line sufficient to break the link even on a payout system. This has happened several times. The result is nothing but annoying as the pilot is already in a pulled in position and has plenty of speed to fly back to land.

The weak link is kept low at 160 lb. We will be increasing it to 180 lb, but I am loathed to increase it further except for heavy pilots.

TAKEOFF DRILL

It seems to me that the first 50 ft of takeoff is the area most needing attention. Our takeoff drill seems to solve the problems associated with this high danger area.

Our drill is: Take a little tension on the line - not too much or the bar tends to be lifted and increases the nose angle on the initial few steps, often resulting in the aircraft becoming an airbrake and breaks the weak link. So a little tension on, then the pilot shouts "GO", car drives off smartly to an airspeed of 22 - 25 mph, then drives on winch person's instructions, slowing down and speeding up. In nill wind conditions the airspeed becomes a little higher and in windy conditions lesser.

Pilot takes first 2 or 3 steps and gets glider flying (tight straps), corrects any wing down problems whilst running, pulls in on the bar a little to prevent the glider lifting off before sufficient airspeed is obtained (same as the hill launch). When sufficient airspeed and level wing attitude is achieved, the bar is allowed to move out a little and glider rises smoothly. At 50 ft the pilot converts to prone and then flys up as he feels correct. More advanced pilots will convert earlier, but only after they have had several flights.

We experienced a little difficulty with an experienced pilot using this technique with his Magic 1 and French connection. After reading Skyting 26 (Shoulder Tow), I have a strong feeling that on pulling in a little on takeoff caused the glider to increase speed and decrease line tension, rendering the glider extra yaw sensitive. The cross wind component presented the rest of us no problem, but for the Magic pilot it was very difficult. We will shortly be experimenting with this problem.

Donnell, I'm enclosing copies of Edmond Potters "The Magic Pilot" computer findings (re flying the line). He is in the process of revamping the figures in to a more presentable format, but I feel as they stand they make fascinating corroberation of our practical findings.

RE THE COCOON PROBLEM

I now fly the cocoon very easily on the line. However, it did present problems in the early days. Even when I was in Texas I did not enjoy it. Since that time I have adjusted it until it fits me correctly and have, as a result, got the following hints to help cocoon launches.

To begin with, I found that a back or bum strap helped to keep the harness snug when having it pulled away from you on the initial bungie position. (Incidentally, the body connection is tied to the main hang point of the harness or lower. This restricts the lifting base bar effect.) Next I bend the boot of the harness in front and fix the handle on the boot into the velcro attached to the lid of the ballast container or directly to the harness somewhere below where the tow connection is. So what we have is enough of the boot bent forward and upward to clear out knees and lightly stuck with velcro. This is only necessary in light or no wind conditions. On windier days the running is not so important. However the days that produce the longest flights and the highest need for comfort are those very light thermal days when you have to run.

Well, there you are with back strap and knee room. You run like mad, take off through the gradient, and, once settled, take one hand off the bar and push the boot away, then convert. Sounds complex, but it works.

VIOLATING SKYTING CRITERIA

Oh, incidentally, Donnell, I am disturbed that some individuals have got hold of some of the information on towing and are doing it wrong. A party in England are towing off using 160 lb pressure using the Skyting bridle and pressure gauge. I was introduced to them by flyers who have visited Australia. I'm doing my level best to advise and set examples, but I'm a little concerned. Perhaps each Skyting issue should have the 8 criteria duplicated upon it.

FOLLOWING THE ROAD

Last and not least, I have to admit to not obeying the 8 criteria - namely No.1: constant direction of tow.

Two weekends ago we experimented with an idea of turning a corner to increase the length of tow by driving the perimeter track of our airfield. We briefed the plan and set up to do a turn at the end of the tow if at any time things did not look good, we would terminate the flight. The first two attempts came to nothing except that the winch and glider moved to the correct position in readiness for the turn. The third and fourth time we actually did it. The wind was steady and not strong but happily cross. This is necessary at our stage.

I enclose the flight plan and course of the best run we have developed. The wind has to be at a certain direction in order to perform it, but it works well. It requires skill on the part of all three of the team to keep the line in the right place. The result was my first real thermal flight. I towed to 800 ft, thermaled to 2000, lost it, played with another, and landed. Flight time 14 min 30 sec. This record has now been broken by the "Magic" pilot, Edmund Potter.

That's all for now from England.

Tony and Rona Webb
Norfolk, ENGLAND
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Cross Wind Launch

Main Runway 1/2 mile.
Pery Track
3/4 mile.
800 ft
Finish.
Wind Direction.
Thermal.
The sharpe corner does present problems in matching speed to keep the line tension.
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1984/10-07

Dear Tony and Rona,

Thank you so much for keeping us informed about your progress in England. Not only is the information you send us interesting and useful, but it also satisfies our curiosity about how things are going with you.

Let me make a few comments on your latest letter. Please remember that you now have more experience (both number of flights and flight time) than I when you consider these suggestions, and use your own judgement as to whether or not to follow them.

1. I am surprised that you are having trouble breaking weak links on takeoff. Since I do not believe your wind gradients are significantly worse than here, I wonder about your takeoff "drill". Specifically, I wonder about your practice of "pulling in on the bar a little to prevent the glider lifting off before sufficient air speed is obtained." Personally I fail to see how the glider can lift off before flying speed is obtained, especially if the vehicle is accelerating and the tension is increasing. If there is sufficient speed to lift the glider into the air, then a split second later (assuming the same nose angle) there will be even more speed. Again, personally, I only pull in on the control bar (1) when the towline is trying to force my nose higher than it should be (as during takeoff before the glider lifts off my shoulders) and (2) when the air speed is too great (as when passing throught the wind gradient or hitting a wind gust, or when the car is driving too fast and I am near the ground). My takeoff proceedure is as follows: (1) Keep the nose high and wings level during the takeoff run. (2) Keep the wings level during the early climbout and be ready for the wind gradient. (3) Upon entering the wind gradient, pull in as needed to keep the towline tension from climbing too fast for the ground crew to adjust and slowly let the bar back out, forcing the vehicle to slow down or else break the weak link. (4) Once things have settled down, continue the climb out in neutral bar position.

2. Since the above does not sound too different from what you are doing, your problem may not be your takeoff technique. It may be your weak link break point. Your weak link sounds a little too weak to me. The basic rule is 1 g, which means it should break at a tension equal to the combined weight of pilot, glider and flight instruments. Of course, it is better to have a link too weak than too strong, so I cannot fault you for what you are doing. I am just pointing out that your values are less than those normally used by others.

3. You did not enclose the copies of Edmond Potters "The Magic Pilot" computer findings as indicated, so I'm not sure what you meant when you said, "they make fascinating corroberation of our practical findings."

4. I am glad you have found a satisfactory method of launching in a cocoon. Your method is different than that used by Bob Faris and described in SKYTING #28.

5. Your suggestion of repeating the Skyting Criteria periodically in the Newsletter sounds good. If I can figure a way to do this without using up too much space, I will.

6. I am not sure you really violated Criterion No.1 when you maneuvered your vehicle to obtain a longer flight. Yes, IDEALLY the criterion is CONSTANT direction, which you violated. But the PRACTICAL criterion is ESSENTIALLY CONSTANT in direction - which simply means that the towline direction changes slowly compared to the response time of the pilot and glider. If the towline is 1000 ft or so in length (as it must have been of you reached 800 ft in altitude), then regardless of how the car moved, the tow direction would remain essentially constant. In fact, on a 1000 ft line, Criterion No. 2 is violated more than Criterion No. 1. In other words, the towline tension varies more rapidly than towline direction when the vehicle maneuvers on the ground (and a long towline is used).

Donnell
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1984/10-08

TOWING EQUIPMENT PRICE LIST

The following equipment price list was sent to me by Mark Tracy. Since the price list is dated as of April 1982, both the equipment and prices are probably out of date, so before ordering anything you would probably be wise to contact Delta Wing Kites and Gliders Inc., P.O. Box 483, Van Nuys, CA 91408. Phone (213) 785-2474 to get the latest information.

You should also realize that some of this equipment is designed specifically to be used with the old, pre-skyting towing system (see photograph), so be careful. But there are several items (quite suitable for safe skyting) which some of you may have been looking for for some time now. (For example, the floats and the high quality cable release systems.)

385.00 - A-Frame stainless
093.00 - Release (Only)
011.00 - Release adj. block
022.00 - Upper release cable
011.00 - Lower reelase cable
011.00 - Release, lever & bracket
005.50 - Release, lever bracket
005.50 - Upper release strap
017.60 - Lower release cable strap
143.00 - Upper release assembly
144.20 - Lower release assembly
030.00 - Inner base tube
041.25 - Float, tail
038.50 - Floats
027.50 - Retainer, float to A-frame
008.25 - Attachment for tail float
003.30 - Tow rings
027.50 - Tow rope - 200 ft w rings
000.20 - Tow rope - 500/1000 ft ft
013.75 - Tow bridle
880.00 - Tow conversion (water)
495.00 - Tow conversion (w/o bar)
318.00 - Tow conversion (land) (no floats)
027.50 - Cable w/fittings
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1984/10-09

WANTING TO GET AIR TIME

We're about ready to do some cautious skyting here in Dayton. It's quite flat around here - we have 2 hours drive to hills in south central Ohio or Indiana. If skyting works for us, it should be a great break-thru towards getting air time.

It's taken me 2 years/350 flights to get 300 minutes air time - not to count a broken leading edge and keel and broken elbow. Don't worry, with all that "experience" I'm super cautious / conservative / controlled now. The elbow was on my 10'th flight, 1'st training day - no bodily injuries since then.

Jerry Martin
Dayton, OH
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1984/10-10

ARIZONA SKYTING

by Doug Gordon
Arizona Windsports
Tempe, ARIZONA

Flying went rather well at the Talltec Butes this past Sunday. For those of you who have never been there, it's a group of 3 cone hills which between them face 360 degrees. They are 150 ft high and, in a strong wind with a cambered batten glider, soarable. Next to the butes are large flat fields - ideal for skyting! On days that the wind is low we can skyte. By the way, Easylock releases have come in. (Ed: Threaded bridle releases.)

Many pilots now have the option of skyting and/or flying the Talltec. By doing 3 consecutive spot landings (100' circle) with "S" turns, you can get your hang 2 rating at Talltec. A hang 2 rating is all you need to go with us to fly at Elsinore (with an instructor present).

Please try to make it to the EVHGA meeting this Tuesday night. There will be a movie (VHS) to see, plus we will talk about the Elsinore trip, the skyting contest in October, and we will make plans for getting together for some skyting-footlaunching. A number of members have told me that they would like to fly (skyte) when they get off work in the afternoon for some quick airtime.
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[Tad Eareckson]

1984/11
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SKYTING NO.31
NOV. 1984
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SKYTING IN SOUTH AFRICA
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1984/11-01

Dear Donnell,

I really enjoyed reading all the newsletters you sent me, finding them informative and interesting. Reading about other fellow pilot's attempts at skyting has given me a lot of confidence and insight (plus caution) in the system.

Gerard Thevenot of La Mouette in Dijon, Franc, tows hang gliders with a trike that he makes called the Cosmos. He uses aero-towing to flight test new gliders and new modifications. The towline passes through the centre of the propellor and reduction drive and is attached to the shoulder straps on the hang glider pilot's harness - there being a release at both ends with a +/- 100 lb weak link.

Most pilots in and around Johannesburg fly La Mouette's Profil and are very keen on aero-towing. Our La Mouette agent has just imported a trike and we are using Gerard's system. We have done about 5 tows and have had one near lock-out which caused the weak link to break. Fortunately, the hang glider (H.G.) was about 1000 ft above ground so there was no problem. This happened at about midday on a bumpy day when the trike flew into some sinking air causing the H.G. to get a lot higher and the rope to become slack. As the tension in the rope was taken up the glider got a wing up and was pulled into a lock-out situation until the weak link broke and the glider recovered normally. We have only one fairly hairy take-off where the glider got a slight wing up on leaving the ground but quick reactions by the pilot brought the glider back to level flight.

Take-off sequence:

(1) Take up tension in the tow rope.
(2) Signal to the trike pilot.
(3) Resist pull - and then run 3 steps and you are off.

We have discovered that it is almost impossible to stall the H.G. so one takes off with a high angle of attack and then pulls in immediately once off the ground. We are using a knee-hanger harness initially but will have to progress to a cocoon harness if we intend doing decent XC flights (which is our ultimate goal).

A group of pilots in Natal have started aero-towing using your harness and have been very happy with the results. We have a problem adapting your harness to our gliders for either skyting or aero-towing. The Profil is designed around a double French connection which makes the keel attachment rather difficult. As you can see by may rough schematic drawing, the pitch connection is not held stationary by the roll connection (unlike the Moyes double connection) but can rotate around the attachment bolt on the roll connection. It is prevented from actually rotating by the front cable so it just flops from side to side when not supporting the pilot's weight. We would have to attach the keel bridle line in front of the connection's front cable but I feel that this may be too far forward, especially since the adverse yaw problem seems to have been alleviated by attaching the keel bridle to the kingpost attachment area. Another problem is harness attachment. I fly with a cocoon harness and can visualize the harness being pulled forward around my neck before I get the chance to put my feet in the boot.

I would realy appreciate your thoughts/solution to these 2 problems.

We may not try skyting due to availability of the trike and the fact that we do not seem to have any suitable towing sites in and around Johannesburg. All the roads are either bordered by fences, telephone lines, or trees, or a combination of the three. I am interested to know how you feel about your harness being used/adapted for aero-towing.

We have semi-desert regions in S.A. that are potential XC record setting areas. These are the areas where the sailplanes fly and, from talks I have had with sailplane pilots, conditions are fantastic. The major problem is that there are not suitable mountains in the area. Towing thus offers us an opportunity to utilize these excellent conditions.

Paul Thomas
Johannesburg
SOUTH AFRICA
+
Right Side View

Kingpost
Keel
1 1/2 ft
Down Tubes
Cable
Pitch Connection
Roll Connection
+
Viewed From Behind

Kingpost
Keel
Down Tube
Down Tube
Cable
Cable
Roll Connection
*
1984/11-02

Dear Donnell,

Well, a lot has happened since my first letter. We have done a number of air tows and have just recently started skyting! The skyting has been very successful and enlightening. We have begun to realize its potential. We don't actually need it in Johannesburg but it will enable us to fly in the best thermic regions which as you can guess have no suitable mountains from which to launch. I was in Europe in May/June and the Aussies have been having great success land towing with your bridle. They were very enthusiastic about it.

AIR TOWING

We have been towing behind a Cosmos Trike which is basically a La Mouette Profil Hang Glider (14 m2) strengthened in all the necessary areas with a tandem seat trike powered by a 440 cc Fugi Robin Two-stroke Twin with a reduction drive propeller. It is very efficient and powerful and could quite probably tow 2 gliders off at once.

Tim (a highly experienced hang glider pilot) has been doing all the towing. The tow rope runs through the center of the prop, having both a weak link and release at either end. The Trike pilot has a large wide-angle mirror enabling him to keep a pretty good eye on what's going on behind him. We have been using +/- 80 m of parachute line as a tow line. Take off is essentially the same as skyting - things just happen faster. Once off, the H.G. pilot must pull in and maintain height of +/- 3 m above the ground to allow the Trike to get flying speed. Once the Trike is off the H.G. pilot must maintain a position slightly above the Trike. The easiest way is to keep the Trike's nose plate on the horizon. The towing speed is a lot faster than skyting so requires quicker reactions. Turns require the H.G. to stay on the outside perimeter of the arc to prevent slack (as in water skiing.) Towing in thermic conditions can be hairy being very bumpy and difficult to maintain ones position in relation to the Trike. We have been towing from a bridle connected to the two shoulder straps on the harness. We have had only one lock-out, which I think I told you about in my last letter. I think that one of the problems is that the towline is too short which gives one less reaction time and removes the natural dampening inherent in a long rope. The advantage of the Trike is that it can tow you to a thermal.

About 3 months ago we heard of a young guy (18) Kobus who had been skyting successfully in Kronstad in the Orange Free State. We had met him about 9 months ago on an away week-end when we had gone to try a new site that we had heard about. (The site is about 4 hours drive from Johannesburg which is about 3 hours drive from Kronstad.) There are no mountains around Kronstad and Kobus was not prepared to drive for 3 hours to go and fly. He had heard about your bridle system from someone. He only knew that the top attachment must be ahead of the king post and the harness attachment at the waist (tow line above the control bar). He made his own bridle out of a piece of rope with an ingenious top release. The bridle remained attached to his harness (knee hangar). He is the only person in Kronstad (average size town) who hang glides. He taught himself how to tow, getting friends to drive for him. He never used a weak link or tension gauge relying purely on signals, which he gave with his legs: scissors for slower, up and dow for faster and scissors open for stop. He has never had a skyting accident which says mountains (excuse pun) for your bridle. The only contact we had with him was at this one mountain and then only briefly. He was then only a beginner. He has been doing regular XC flights of +/- 35 km from the tow field, which is on a friend's farm, to a sports field near his parents' home in town. He flies a Zenith II which is a South African copy of the Comet I. It is a far more mellow handling glider than the Comet, being lighter and more responsive on roll, a bit slower on top speed and generally having a degree less performance. He has experienced no adverse yaw problems and has towed in most conditions. He is (we hope was, now) unaware of any of the dangers of hang gliding plus developments in the sport that one gets/learns through mixing and flying with other piots.

A fortnight ago three of us went down to Kronstad to investigate. We watched Kobus do a couple of tows and then tried ourselves. The three of us were initially a bit scared and thus cautious. We used a 400-ft towline and each had 2 successful tows, all of us being pleasantly surprised at how easy it was. Tony and I flew Profils and Matthew a Saba (Aussie copy of Magic 3). On my first tow the wind swung to about 45 degrees cross as I started running, but I got off easily and smoothly. It feels so natural and easy. You just run until you feel comfortable about T/O and then just ease the bar out a touch and off you go! None of us experienced any problems and we left Kronstad determined to give skyting a full go. Kobus skied out that day, leaving us experienced pilots looking on in envy.

Matthew, Willie, Kieth, Lorny and I went back 2 weeks later. This time we went prepared with Hewett bridles, weak links, a tension guage and 700 m of tow line, determined to do it properly. Our conclusions to the week end were a bit startling! We found towing from the shoulder bridle easier and safer!

We started the day off by using the Hewett bridle. I attached the keel mount to the strap that holds the front of my pitch connection to the keel. I used my cocoon harness and just attached a shoulder bridle to the loops where the main suspension straps attach to the harness, which is also where the leg straps attach. The other end of the Hewett bridle was attached to this shoulder bridle. I used a 2-ring release on the keel. The tow rope was attached via a weak link to a sliding ring on the Hewett bridle. The Hewett bridle thus remained attached to the harness once I had released, this being no problem as we were skyting in a large flat open field (occupied by springbok and wildebeests, which is like a small buffalo). I had 2 successful tows with the Hewett bridle, the first in the early morning and then a bit later. I found that I did not have as much control over the glider's pitch and on the second try the glider yawed around a bit but not excessively. I towed with the bridle passing through the trapeze and don't feel that that plus the fact that the one end remained attached to the harness would have adversely affected anything. For the 3rd tow I used the shoulder bridle and felt more comfortable with it - it feeling more natural to me. So much for my experience for that day.

Matthew's were far more alarming. He had the first tow of the day when it was very still and smooth. He uses a Steinbach pad harness, which is basically a pod harness made out of dacron, sponge and webbing with bomb-type doors for ones legs, which are zipped closed in flight. The Sabre has no French connection system so the H.B. was connected up normally with the lower line running beneath the control bar and attached to the harness leg straps (through the bomb doors) which are like conventional harness leg straps. He suffered from terrible adverse yaw. We moved the keel pocket, which is +/- 8 cm in front of the kingpost. On this flight Matthew tried flying the glider faster, slower at different towline tensions and different corrective control bar inputs, remaining neutral but to no avail. He then tried the shoulder bridle and the problem was solved. The glider does still yaw slightly but nothing to get worried about. The Sabre seems to climb at a far steeper angle than other gliders: so we tow Matthew using less tension on the gauge, +/- 35 kg for him and up to 50 kg for me. Matthew weighs 72 kg and I 80 kg. Matthew had 3 tows with the H.B. in our attempts to cure the adverse yaw. Matthew is one of S.A.'s best pilots, finishing in the top 20 in the last world champs in Tegelberg and the rest of the pilots who have tried have all been highly experienced including myself.

We had one near lock-out that day towing Lonnie (an American from Idaho out here working on the mines) and his Magic 3. He is an experienced pilot and this was the first time that he had tried towing. He was using the shoulder bridle and hit a gust whilst trying to get into his cocoon harness at +/- 100 ft off the ground on his second tow. The glider started banking to the right and then the bank angle seemed to accelerate very quickly to +/- 60 degrees (seen from behind). I shouted, "Lock-out!" over the radio but before I had finished, the glider righted itself and the tow continued. I have never seen a glider change direction so quickly both when it banked to the right and when it recovered. Lonnie said that he felt the glider start turning to the right so he reacted normally but the glider suddenly banked steeper and he was pulled over to the left and the glider righted itself (importance of a good quick release system!)

In retrospect the reduced pitch control when using a H.B. is good when towing beginners or inexperienced pilots. Another thing I discovered is that my glider chooses its own angle of attack under tow which is about 20-25 cm back from neutral and about 500 fpm climb. The H.B. allows you to tow to a higher angle when running beneath the control bar. We found this a limiting factor using the shoulder bridle as we fly with speed bars. (Also when using a standard bar.) At the top one has to push out a bit to maintain the climb thus aggravating the problem. Towing at +/- 25 mph (glider speed) seemed a comfortable speed to tow at.

I/We would really appreciate your thoughts/ideas to this letter.

Paul Thomas
*
1984/11-03

Dear Paul,

Since I got your follow-up letter before getting around to answering your first letter, and since your follow-up letter showed that you had already obtained answers to the questions you asked in your first letter, I am going to skip the answers to your first letter and try to answer the questions in your latest letter.

(1) Yes, I have thought about (but not tried) a shoulder towing bridle. Skyting No. 26 contains my thoughts on the matter. If this material does not answer your question, let me know.

(2) To be honest, I was surprised to hear that the glider yawed more with the Hewett Bridle than with the shoulder bridle, but now that you mention it, the reason seems clear: The H.B., is usually attached to the floating KEEL instead of the glider's true center-of-mass.

You will recall from SKYTING No. 12 that the reason for the adverse yaw is that attaching the towline to the keel violates Skyting criteria No. 2 (Center of mass attachment points). The tension in the keel line tends to force the floating keel to the side, causing the glider to yaw away from tow.

Since the shoulder bridle places the full thrust of the towline on the pilot, less is transferred to the floating keel (although some is transfered through the pilot's hang straps). As a result, the adverse yaw is less pronounced with the shoulder bridle.

(3) I am sorry, but I do not understand your third question, "Will leaving the H.B. attached to the harness affect the working of the H.B. in any way whilst under tow?" Obviously, where the bridle goes after release has no effect on how it performs on tow. Part of my confusion is that I do not understand exactly how your release mechanism operates.

You said that you used a "2-ring release on the keel" and that "the tow rope was attached via a weak-link to a sliding ring on the Hewett bridle." Is this sliding ring the normal apex ring? If so, then what stays attached to the harness? Are you talking about the shoulder tow harness used to attach the H.B. to the body of the pilot? If not the above, then how does releasing the keel latch accomplish a release of the towline while leaving the bridle with the pilot? You can see my confusion.

(4) The best towline to use is what you have available. There is generally a lot of wear on the towline as it is hauled back on or drug behind the vehicle after release. Thin steel cable costs more but wears longer and has little stretch, so it is ideal for the non-stretch portion of the towline when you want long towlines. Nylon works well and is particularly suited for the stretching portion of the towline. Polypropolene is least expensive, but does not wear very well.

More important than what you use is how much stretch you have. You need enough total stretch to allow the pilot to correct for wind gusts and thermals, but not so much as to confuse the driver as to how fast to drive. Theoretically, the more stretch the better. Practically, many drivers have problems maintaining constant tension when the stretching line is more that 500 to 1000 ft. The stretching line needs to be about 4 mm diameter nylon or polypro cord. Personally, I prefer parachute shroud line which consists of several load-bearing strands of twisted nylon line enclosed within a protective sleeve of nylon.

(5) The towline tension should be reduced for high performance gliders (or any other gliders) until control is easily maintained under tow. Since greater towing forces result in greater deviations from the glider design performance, all initial flights should be made with no greater towing force than is required for takeoff. This normally means about 75 pounds (or maybe less).

Of course, your climb rate under these conditions will be very low unless the glider has exceptional performance. But once the towing flight characteristics of the glider are known, the towline tension can be gradually increased to higher values. Many experienced tow pilots like to tow at towline tensions approaching the weaklink break point to get maximum climbout. Of course, if they miscalculate and exceed the weak link break point, instead of a fast climbout they will have a short flight. Naturally, they are sure of their ability and their glider's performance before towing under these conditions.

(6) The ideal length of a H.B. is the shortest bridle which does not interfere with control bar or pilot movements. Longer bridles simply cost more and have more stretch while shorter bridles can cause control problems. So if you err, do so on the long side. For most modern glider-pilot combinations, I would not recommend a bridle whose threaded (total) length is less than 20 ft.

(7) No, one should not have to strengthen the hang strap for towing. You should NEVER be towing in conditions anywhere approaching the design conditions of a harness. In other words, free flight stresses on the hang straps will significantly exceed the towing stresses. Remember, the weak link breaks at one g, so the towing stress on the harness is less than 2 g's, while free flight stress can easily exceed 3 g's. This is because in free flight you may not be able to avoid severe turbulence, which can cause tremendous strain on your glider and hang straps. But when towing, you can and should obviously release from tow long before the turbulence becomes this great.

(8) Theoretically, the best air speed to tow at is that of minimum sink, as this produces the fastest climb rate. However, this is rather close to the stall speed of the glider and if the towline should suddenly go slack (worn towline or weak link break, or vehicle stalls or stops), the glider could stall. The greater the towline tension, the more catastrophic this could be. So the general rule is: "Tow faster as the towline tension increases, particularly as you approach the weak-link break point." Personally, I like to tow under conditions where my towing speed is about 25 mph.

I hope this answers your questions. If not, let me know and I'll try again.

Donnell
*
1984/11-04

COPY NEEDED!

If you don't want the next issue of SKYTING to be a monologue, you better get busy and write that article of letter you've been putting off.
*
1984/11-05

INCIDENT REPORTS

The following two incidents were reported by Tony and Rona Webb from Norfolk, England. I really appreciate such reports because this is the only way we can ever hope to avoid similar accidents in the future. Remember, there are only two ways to learn about dangerous accidents: (1) experience from yourself, and (2) learn from the experiences of others. Personally, I have learned all I want to from the first method and would like to do the rest of my learning with the second method. So please report the skyting related accidents and incidents you hear about or witness.

INCIDENT No. 1

DATE: Feb 1984
SITE: Flixton N.S. Runway (Main).
SYSTEM: Payout winch.
GLIDER: Cherokee
CONDITIONS: Damp occasional showers.
WIND: N.N.W. Light 5 mph
DESCRIPTION:

Take off procedure following necessary Preflights. Wind cross but not excessive.

Tow pull slow and laboured, Cherokee side slid across to side of runway, eventually off to 50 ft, payout not smooth, driver slowed down, glider began to descend, airspeed was slow, winch man released tension recognising pilot was unhappy and ready to abort, tension remained applied due to brake grab in wet conditions, pilot released in lee wing down attitude. Full weight shift and insufficient arispeed failed to correct landing approach. Glider side slip to ground and impact was absorbed particularly on lee or right wheel.

GLIDER DAMAGE: Bent A Frame and twisted
LESSONS: Always teach driver with practice and theory. Rectify braking system on winch. Never use two inexperienced crew together.

INCIDENT No. 2

DATE: 15.4.884
TIME: 11:30
SITE: Flixton E - W Runway.
GLIDER: Cobra
SYSTEM: Payout winch on trailer towed by automobile.
CONDITIONS: Mild sunny. Little thermal activity.
WIND: West. Gusting 10-15 mph, strengthening later.
DESCRIPTION:

Novice pilot training untethered, previous flying same system.

All Preflights performed.

Normal short line 2' to 4' level flight. Slow car speed used after a period of ground handling familiarisation, tight elastic to bridle to reduce nose up in neutral.

Pilot being particularly awkward, not at all responsive to instruction, weight shifted the wrong way, pushed out hard, weak link broke and proceeded to wing over at ground level. Instructor took hold and with effort righted the glider.

GLIDER DAMAGE: Small bend in upright. Grazed nose. Bent keel 6" from nose.
LESSONS: Side tethers to be used in winds over 12 mph with T2 pilots. Nose tether to bridle to reduce pitch. Tight elastic restraint insufficient.
*
1984/11-06

THREADED BRIDLE ON LAKE DELTA

Dear Donnell,

A short note to let you know what's been happening at Lake Delta, which also gives me a chance to practice on the Apple IIe which the chemistry department just received.

Things were a bit slower this summer than last due to the favorable conditions for mountain flying. We did log some 57 tows and introduced two new pilots to deep-water skyting (their first experience at towing). We are towing to altitudes of between 2500 and 3000 ft AGL. I received the highest tow of the season at 3200 ft AGL.

At the start of this season, we elected to try the threaded bridle although there was some reluctance on Dan's part. I understood his position, the possibility of entanglement or being whipped. After reading the good reports in Skyting, it was worth a try. It seemed the slick set up for deep water towing. I pushed to give it a shot.

We used a prestretched 22 ft length of 1/4-inch 12-braid polypro line. The main reason for using this type of line was to allow us to splice a small loop in the end of the bridle. We needed a loop in order to use the Yarnel type release that we have. We did not want to add any weight to the end of the bridle by using any kind of metal ring. We suspend the release from a hang strap attached to the keel in its normal position. This allows the release to hang down about 16 inches, making it easy to hook the bridle in while the pilot is floating in the water. The release is cable activated with the lever mounted on the right side of the base tube.

The bridle has worked out very well. It has been released under pressure and without any pressure with no problems encountered. I was hit once on the heel after releasing. I was dragging the rope over the boat and released with the bridle line running almost straight back through my legs. The whip was not painful but with some after thought decided good judgement would keep me from duplicating the situation. Though our experience has been favorable using the threaded bridle it is not to say that it is fool proof. I have come to believe nothing is fool proof as we are always on our guard.

The cold weather is now upon us and our thoughts drift toward land towing. We are more and more convinced that for land towing areo is the way to go. Who knows, maybe I'll win the lottery and my next letter will tell of our Tug Tow adventures.

May your winds blow straight in, BE SAFE, and hang in there!

Don Boardman
Rome, NY
*
1984/11-07

COMMENTS ON TOW TRAINING TECHNIQUES

Dear Donnell,

Liked parts of No. 28's tow training techniques.

Some quick comments:

(1) Wings level. We have used a cross-wind take-off style that has the kite turned toward the X-wind, with the windward wing slightly down. Why? As soon as you start to be towed, the glider will be rotated toward the tow rope, lifting slightly the windward wing because of its slightly higher air speed. By the time you lift off, the kite is level and pointing toward the car (tow vehicle).

(2) Nose high. We have some compounding of problems here. If the bottom bridle ropes are high on the harness and the pilot has a large tow frame AND the nose is held high, the increase in tow tension can lift the base bar up and forward sending the nose too high. This will result in stalled wing/s from too great an angle of attack. One wing will drop and a ground 180 degree turn will result. Usually costs at lease one upright. Usually only happens once to each pilot with the above mentioned gear.

(3) Foot shuffle. Excellent way to go - may also stop them treading on their harnesses which have not been correctly held up during the takeoff run.

(4) Equipment. I am surprised to hear of people still using DEADLY DOUBLE RELEASE BRIDLE. Must be a throwback from the old towing days.

(5) Communications. Firstly, I do not consider that an "observer" (or "launch director") is either necessary or desirable. The best observer of all is the pilot. We use the following system:

Each pilot has a CB on one upright. Usually has a hand mike.

DRIVER: Ready to take up tension.

PILOT: Take up tension.

DRIVER: Tension on. (Usually 20-30 lb on rope.)

(Up until now the glider is still parked. The pilot checks his bridle, etc., and clips down his "speak" button. It holds the pilot's radio on "Transmit.")

PILOT: Clipping on mike.

(The driver can now hear the pilot lifting his kite, etc. When steady and level, the pilot will command.)

PILOT: (three times clearly) Go. Go. Go.

(The driver will be able to hear any of the other commands by the pilot, each spoken 3 time clearly.)

: Stop. Stop. Stop.
: Faster. Faster. Faster.
: Slower. Slower. Slower.

If any other command is heard or any command is not understood (bad radio?), the driver will STOP.

The pilots soon learn to use the correct commands and to have their radios and aerials in good condition.

At the top of the tow, the pilot may use "Stop. Stop. Stop." or the car may have reached the end of the strip and will stop without receiving a command. After release, the pilot will say:

PILOT: Released safely. Clipping off mike. Thanks.

This advises the driver that the pilot is off the line. It reminds the pilot to clip off his mike.

We then have the driver turn and drive back to the take-off area WITHOUT UNCLIPPING THE ROPE. Then next pilot (or helper) will unclip the rope from the car. The driver then returns to the end of the rope ready for the next tow and clips on the tow rope.

By now you're probably wondering what happens to the leader and weak link which is back at the car. We use two leaders and two weak links in the tow rope. But we only use those at the pilot's end during each tow. The loop in the main tow rope at the car end is attached to the car hook. The leader is put on or in the tow car. This saves heaps of time. I've often passed the falling tow rope on my return drive before it has hit the ground. If any snagging occurs, the weak link will break but this rarely happens if good strips are used.

The "Flatlands H.G. X-C Challenge" is starting to come together. A few of us went to the site last weekend - a 3-day holiday weekend - and I managed an 80 km (50 mi) flight in the strong conditions. It's only the beginning of spring here. Should be good in summer. A semi-local pilot flew 30 km toward his home on the last day, but came back to have a beer with the rest of us before going home.

A group of Queensland pilots and I are going to Alice Springs (center of Australia - all desert) in mid November to attempt some world records. We will be using the local sailplane strip. I'll let you know what happens.

Denis Cummings
Singleton, OZ
AUSTRALIA
*
*

[Tad Eareckson]

1984/12
*
SKYTING NO.32
DEC. 1984
*
1984/12-01

HAPPY 4'th BIRTHDAY, SKYTING

If we define the birth of skyting as that day during the Christmas Holidays of 1980 when the theory and techniques of skyting were written up for publication in the hang gliding literature, then Skyting is 4 years old this month. During this time, progress toward a truly safe, established towing system has been slow but steady.

Unfortunately this progress from time to time has been painful (even though the pain has been predictable). For example, you will recall that in last year's birthday message (in SKYTING No. 20) I wrote, "I expect the towing fatalities to increase this next year because of general lack of respect for the dangers of towing among the increasing number of tow pilots." Well, the latest issue of Hang Gliding (Dec. 1984, p. 6) confirms this prediction by stating, "The USHGA has recently received reports of five very serious accidents involving the surface towing of hang gliders. Four have been fatal, and the fifth probably should have been."

Since I, personally, have received no written reports on any of these accidents, I cannot fill you in on any of the details. Apparently several of the fatalities were the result of inexperienced pilots being towed as part of their initial training. USHGA, therefore, suggests that "towing of any hang glider, whether surface or aerial, be limited to pilots of at least Intermediate skill rating. Exceptions would be for pilots of Novice rating who exhibit strong launch skills, under the direct supervision of instructors with proven tow experience."

USHGA chides itself for not having established a formal set of towing guidelines in time to prevent such accidents. Since I am not sure anyone (particularly USHGA with its low involvement with towing development) knows enough about the many aspects of towing to establish a realistic set of safety guidelines, I would rather chide USHGA for its lack of involvement in towing development and its failure to keep its members informed about towing problems and solutions. (Only after the Board of Directors decided a set of guidelines needed to be written was I contacted by USHGA for any information on towing, and there is still no indication that USHGA plans to subscribe to the SKYTING Newsletter in order to remain abreast of future towing developments.)

Although USHGA is still clearly outside of the towing mainstream and strongly opposes the practice of tow training beginners, please realize how far it has come in the last four years. In 1980 ((1981)) it wouldn't even finish publishing the original series of articles on skyting, while today it not only condones the practice of tow training Intermediate (or better) pilots (under a qualified instructor) but even admits tow launching as a valid option in regional competition. Note, however, that this does not meant that USHGA's attitude has really changed. It still retains the policy of opposing - or at least remaining silent about - any developments along the frontiers of knowledge, and still goes about establishing rules to govern any practices which are reasonably well understood. As frontier knowledge moves into the realm of general practice, USHGA becomes involved. USHGA, therefore, acts as a gauge of how far towing has come. If it is an accurate gauge, then towing has come a long way in the last four years, but it still has a long way to go before reaching its full potential.

So much for the past, now what about the future? Will towing fatalities continue to rise? I am afraid they will. There is still no widespread effort to EDUCATE the growing numbers of towing pilots, particularly about the known dangers associated with towing. Will regulation increase? I am afraid so. Regulation is the bureaucrat's solution to any problem, and as towing fatalities increase, the inevitable regulation will also increase (if not by USHGA, then by the FAA). Eventually, of course, education will be emphasized and then as pilots finally learn HOW to tow safely, both established towing regulation and common towing practices will follow suit.

Skyters, I am afraid that this next year is going to be the worst yet as far as towing safety is concerned. There are simply too many pilots taking up towing with an ignorant and carefree attitude, and our own national efforts are being directed toward regulation (which these people are going to ignore) instead of education (which they still may ignore). Let me encourage you now, in this Skyting Birthday Message, to do your best not to become one of these expected statistics. Don't even let your friends become one of these statistics.

Please remember - and here I'm assuming you have already upgraded your skyting system to current safety skyting standards by eliminating those components and practices which have been documented in the SKYTING Newsletter as being dangerous - please remember that the greatest single danger to an experienced skyter on a proven system is a complacent or carefree attitude toward towing.

Let me also take this opportunity to wish all of you a very Merry Christmas and to remind any of you don't know Christ personally, that the greatest single danger to a person passing through his life is a complacent or carefree attitude toward Him.

Merry Christmas to All,
And to All a Good Skyte.

Donnell
*
1984/12-02

SKYTING IN HOUSTON

Dear Donnell,

Hi! I know it's been a long time since my last letter but I figured I'd give someone else a chance to talk about their experiences. Skyting in Houston has had its ups and downs. We were sidetracked for a long time experimenting with aerotowing, until the FAA shut us down. I fail to see how people manage to aerotow with no problem in other areas of the country while we're under the threat of $1000 fines if caught again. So we're back to skyting.

We've had two major problems with towing here in Houston. The first is trying to find 3 people who aren't going to Packsaddle Mt. that weekend, and the second is finding a good tow road. We now have several good roads (1+ miles) facing several directions. The problem is that the landowners aren't friendly, so we have no setup or landing areas. The roads are all county roads (dirt) and the local cops usually come by to watch. Because of the landowner situation we must take off and land on the road. Obviously this means no X-wind takeoffs, since it would require a X-wind landing. This can be heart breaking at times, such as last July 4, when we had cloud streets forming at 9:00 AM and couldn't find a road that faced into the wind!

As a result, the best flight to date was performed by me last March. I was towed up to 900 ft, released, sunk down to 700 ft, found a thermal (my first thermal experience!) and made it up to 1100 ft, landing 15 minutes after takeoff. It must have been the only thermal of the day, as no one else was able to get anything more than a sled ride. We'll do better if we can ever get together when those 40 mile cloud streets I've been talking about for 5 years start forming next spring.

In the meantime, we've found that you really do need a CB and a HEADSET. We've had people use hand mikes that were permanently switched on and mounted on the base tube while under tow, but couldn't hear them when they had the bar stuffed. YOU NEED A HEAD SET WITH EITHER A FINGER SWITCH OR A VOX! Also, NEVER lock your CB in the transmit mode. Occasionally, the ground crew will need to talk to the pilot in order to pass on such information as the winch is stuck or the towline has become caught in the trees.

We've also found that not all gliders tow alike. Many Houstonians prefer to have the body attachment at the shoulders, as this permits better nose angle control upon takeoff since the rope passes through the control bar. They also complain that with the 1200 ft of rope that we use, placed under the control bar when you use the hip attachment point, you have to gain 200-300 ft before the bridle no longer touches the control bar. However, I still fly with the hip attachment and the rope under the control bar. The reason is that I find that the rope no longer is a problem above 50 ft. It does become a problem above 500 ft when I fly with the point of attachment at the shoulders and the rope passing through the control bar, though, as the rope begins to touch the base tube. This problem gets worse with height, forcing me to pull in. I find I can't get above 900 ft this way. I fly a Raven and have discovered that Wills Wing gliders all have control bars that are placed further forward than the rest. I suspect that the same problem may exist for other gliders, especially if they have speed bars.

As far as the high angle of attack on take off is concerned, I find that it actually helps me hold the glider steady, along with rope tension, while waiting for take off. I know many people worry about a broken weak link at 20-50 ft, but I can assure you from personal experience that it really isn't a problem. If you are very close to the ground, continue the flair and land normally. If you are higher up, then you will already be flying enough above your stall speed to get the nose down safely. Even if you do stall, the stall will occur after you get the nose down significantly, leaving you with a very gentle stall.

We had our annual L/D contest at Barker Dam several weeks ago. Saturday rolled around and the winds were blowing NW at 15-20 mph. Barker needs E winds and we couldn't fly Addicks because it was full of water! You remember Barker, it was the small hill you flew when you and Red came to Houston. Well, we had gotten a great deal of media coverage for it and we didn't want to waste it. The least we could do was set up a static display and tell people to come back tomorrow. Well, we did more than that, we people towed. I have never done it myself, and there was more than one skeptic in the audience. We had 250 ft of rope and 100 ft of bungee. It reminded me of the old days on Padre Island. I was the only one to fly, as no one else wanted to. I got eight flights, with 2-6 people pulling. The wind wasn't strong enough to let me kite, but I did get one flight of 300 ft altitude gain and about 2 minutes! The pullers usually ran out of running room because of the fence and I'd have to come down. Everyone was suitably impressed, and I'm looking forward to doing more of it this winter. I wonder what the world record is?!

One last thing, I've been thinking of going to a single point release, but I hate the idea of dragging the bridle around with me. I thought of a possible solution. After you release the line, you release the top end of the bridle. You are now dragging the bridle around with you from your waist. If you put a string loaded take up reel on your bridle, the rope will be pulled up and out of the way. The only problem with this idea is that you have to be sure that the reel doesn't start to take up the bride until you're ready, or else you could get tangled in the bridle while flying.

Well, this letter is quite a bit longer than I had anticipated, but I guess a lot has happened here since I last wrote. Happy flying, and perhaps I'll run into you again at Packsaddle sometime.

Henry M. Wise
Houston, TX
*
1984/12-03

HENRY WISE FLIES TO ALTITUDE FROM MOUNT BARKER LANDING FIELD VIA HUMAN-TOWING.

!?
FASTER... FASTER!
CRACK!
WOW--AT THIS RATE, HE'LL FLY HIGHER THAN MT. BARKER!
GOOD HEAVENS!
MT. BARKER HEIGHTS TRAIL
-->
YARK!
SKLEEREEEEEEP!
MOAN!....
UGH!
Hardy Snyman '84
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1984/12-04

CROSS COUNTRY TOW PILOTS ASSOCIATION BEING FORMED

In 1983 a small group of local pilots began working with the skyting center-of-mass land-towing system. Since that time we have refined our equipment and methods to the point that flights are now routine and we have trained over 20 pilots. Our normal altitude gain on tow is 2,000 to 2,500 ft and our cross country flights are now out to 40 miles. The potential for 100 plus miles is only a matter of catching the right conditions.

We have available what is probably the best land towing site in the Midwest with an east-west 2.5-mile road located within a park that is surrounded by farm land. It is located midway between Chicago, Illinois and Milwaukee, Wisconsin.

Our goal is to expand the number of qualified pilots and to promote skyting for its cross country potential within the Midwest. We also desire to gain some control over the use of our state-owned tow site but presenting a unified front. The use of the park on weekends must be shared with other organized groups which puts us at a definite disadvantage as individual pilots.

We therefore have formed the Cross Country Tow Pilots Association for this purpose. We need your support and ask that anyone who has towed with us, wishes to tow with us, or simply wants towing information to join our association. Our stated objectives include:

(1) To promote XC in the Midwest by introducing qualified pilots to skyting.

(2) To periodically publish newsletters that will disseminate skyting information. (The first newsletter to go out this fall will include procedures and equipment required to tow with our group.)

(3) To organize an annual tow meet.

(4) To preserve and increase availability of our tow site.

Membership through 1985 is $20 and payment must be received no later than 12-1-84 to receive our first newsletter.
*
WHERE TO GET SOME SKYTING COMPONENTS
*
1984/12-05

Dear Donnell,

I am interested in putting together a tow system and need to know where I can get reliable releases and plans for information or releases please let me know.

Larry Tudor
Draper, UT
*
1984/12-06

Dear Larry,

In my opinion, the three most reliable release systems used in skyting today are the three-ring release, the sailplane-type release, and the threaded-bridle release. The first and third are triggered by a pull line and the second by a cable release. The first requires a slight amount of tension on the line, the second can release a completely slack line, and the third requires very little tension. The first costs about $30.00, the second costs about $150.00, and the third costs about $50.00.

You can obtain three-ring releases from High Energy Sports, 2236 W. 2nd Street, Santa Ana, CA 92703, Ph. (714) 972-8186 and from Midwest Motorglider Supplies, 2638 Roberts, Waukegan, ILL 60085.

At one time you could obtain conventional towing releases (of the sailplane type) from Delta Wing Kites and Gliders, Inc., P.O. Box 483, Van Nuys, CA 91408, Ph. (213) 785-2474. (I do not know whether or not Delta Wing has developed a release designed specifically for the center-of-mass towing concept.)

The threaded-bridle release is called a Sheet Stopper and may be found in your local marine supply shop. You can also obtain a threaded bridle release from Midwest Motorglider Supplies, 2638 Roberts, Waukegan, ILL 60085.

You should study the back issues of SKYTING to learn the advantages and disadvantages of the various bridle designs currently in use and how these releases are incorporated in these designs in order to provide provide safety. By the way, statistics show that the double-release system originally used in skyting (and still used by many uninformed pilots) is generally not as safe as a good single point release system. So make sure your design is up to date before proceeding too far.

I know of no source of plans for either winches or reels. I do know of a few manufacturers of payout reels: High Perspective in Canada; Lezair, ((Lejair)) 41 Kinsdale Drive Thurby Lodge, Leichester LE5 2PS, UK; and Front Range Hang Gliders, 1621 Wagon Torque Dr., Ft. Collins, CO 80521, Ph. (303) 482-5754.

Donnell
*
1984/12-07

A REGIONAL COMPETITION FROM A WHUFO'S POINT OF VIEW

By Mary (Mom) Hewett
Pinecliffe, CA

Before I attended the Region 4 Hang Gliding Competition in Salida, Colorado, August 2-5, 1984, my life tempo had been hurry up and wait, wait and wait. One either learned patience or waxed impatient. (I opted for the former.)

Also, one either likes hang gliding or one does not. And, in Colorado at least, hang gliding is controlled by the weather. I learned that the first day. While the pilots foot launched from Mt. Princeton, I sat at the finish line at the Salida Airport, 16 miles away, waiting waiting and waiting. Would you believe I never saw a hang glider gliding? Three made the half-way mark but not one came within sight of the finish line.

The second day was considerably better. The task was the same.

Some highlights were: One pilot misunderstood the radio transmission at the starting gate and, consequently, completed his excellent flight -- under penalty. Another crossed the finish line to win the competition for the day and went on to fly a total of 80 miles cross country. One did aerobatics, ending his performance by bouncing off a barbed wire fence when landing -- known in some South Texas hang gliding circles as the Texas Bounce. One flew in unnoticed and circled over and over the finish line, inquiring, "Have I crossed the threshold yet? Where is that threshold?" while the spotters instructed a different pilot some distance away whom they anxiously had watched recover from a near catastrophic sink into a wilderness, tree-covered 2000-foot bowl in the mountain range.

Oh, well. Hang glider pilots and crews are human, too (I understand) and are, therefore, subject to human error.

The next day the weather looked great. The pilots were on time for the meeting at 8:00 A.M. and at 9:40 were at the launch site (suitably dubbed the Cactus Patch), in the San Luis Valley on US Government BLM, Road 58EE, for the first towing competition (the first towing competition ever, incidentally), wind socks in place.

Two pilots, who had never towed until after the competition the day before, had arrived early for a few more practice flights and were finished about 10:00. There were thermals, the tow was ready, and everything looked "go" to me. But, not so.

Everyone, but everyone, was doing his/her own thing -- completing set up, checking equipment, going back for forgotten essentials, discussing clarification of rules, pulling cactus stickers -- the first Cactus Patch kid and been borne! -- cutting nylon ties with a flickering open-flame candle in a 7 mph wind, eating, reading, knitting, conversing -- everything except towing and hang gliding!

Chaos? Nope, Just waiting for "optimum." In my unlearned opinion, optimum came and went several times -- unnoticed.

Anyway, while waiting (still!), I observed. Curly heads, bald heads, sheared heads and pony tails. Full beards, mustaches and all the in betweens. Short guys, tall guys, slim trim and stocky. Babies, children, grandmothers, wives, girl friends and pets. Long sleeves, no sleeves -- no shirts! -- T-shirts, ski jackets, blue jeans and shorts. Helmets, floppy hats, bandanas, sun visors. Bare heads, bare backs, bare bottoms (well, partly exposed cheeks!) and bare feet. Sandals, sneakers, hiking boots and moccasins. Tradesmen, business men, manufacturers, architects, contractors, construction workers, realtors, jewelers, teachers, professors, students, journalists, publishers, lecturers, directors, secretaries, computer programmers, psychologists, biophysicists, dancers, homemakers and the unemployed -- all these drawn together by the mutual age-old desire to fly (or see man fly) free as a bird, this time at a hang glider meet in colorful Colorado, waiting around for optimum.

Well, optimum finally arrived (when and how I don't know) and the sniffer got off at 11:31. Another flight got off about 11:44, broke the weak link, but gained altitude and sailed over the launch site, dropping the bridle among the unscathed gliders and spectators.

Bull's eye!

Then everyone got in the act, or wanted to, including the weather. No one reached the finish line (back at the Salida Airport some 22 miles away) but two pilots made the half-way mark and another came close. (Two were never launched.) Ground crews, including girl friends and the meet director, rescued the rained-and-hailed-on pilots while dust devils, rising winds and threatening rain necessitated the hang gliders at the launch site being put back in their cocoons.

About 1:30 everyone descended on Katy's Kitchen in Villa Grove to eat and wait on the weather. (Have you ever waited on the weather?)

The storms went around the valley on the back sides of the enclosing mountain ranges and about 4:00 everyone assembled at the launch site again. The sun came out. Some of the pilots began setting up.

The winds died down, the clouds formed again and the meet was called off. About 1 minute later the sun came out, the wind came up from the right direction and the meet was on again. However, the winds were so variable it took nearly an hour to launch a sniffer, who came back and hung hovering some 200 feet above the launch site. To get some action the pranksters in the bunch fired flares at him.

About 6:00 P.M. the meet definitely was called for the day.

The last day was something else.

Enthusiasm and expectations were rampant. The decision was to foot launch from Mt. Princeton in the morning (same task as before) and to tow at the airport runway in the afternoon. The weather looked that good.

So, away we went to the top of Mt. Princeton. Early.

Sniffers and fun flyers -- off and flying -- but not enough lift to get over the mountains. No competitors in the air.

10:00 A.M. Wait. 13:00 A.M. Wait. 11:30 Wait.

11:38. Rain -- not lift -- from the promising cummies.

12:38. Rain and more rain. Wind. Thunder. Lightning.

Hang gliders make excellent umbrellas -- if the wind doesn't change and the lightning doesn't flash. Also, hang glider pilots make excellent weather watchers.

1:40. No wind, no lift, no sun, no life. Dead birds.

2:04. Sunlight!

2:08. Lowering clouds.

To beat the weather, the task was changed (finally!): A speed race to a meadow in the valley below. Free choice of launch sites and order of launching. Even a one-on-one challenge!

2:45. Spotters in place. Everyone! Go for it!

They did -- swooping around the mountains, shooting across the valley, making like birds -- at 47.55 mph (winner's average speed).

Wow!

If I weren't 70 years old, and fragile, I'd go for it, too.
+
A sniffer having fun in lift too weak for the competitors.
+
If I can't catch a thermal, maybe I can catch a dog.
+
Our genial host on whose ranch we camped out and whose bathroom 27 of us (at least!) shared.
*
1984/12-08

A REGIONAL COMPETITION FROM A SKYTER'S POINT OF VIEW

by Donnell (Son) Hewett
Kingsville, Texas

The previous article was written by my mother and submitted several months ago for possible publication in Hang Gliding Magazine. Since there has been no response from that magazine, I decided to publish it here in the SKYTING Newsletter. After all, the Region 4 Hang Gliding Competition was the first USHGA sanctioned land-towing competition held in the history of hang gliding. And although the one day of tow launch competition was declared invalid (thereby having no effect upon the competition results), the meet did provide an opportunity to evaluate the feasibility of tow-launched competition.

As you can see from the previous article, three of the four days of competition were conventional mountain launch. This is because the pilots were more familiar with that format and it was important that a "valid" meet be held. No one was eager to gamble the validity of the whole meet by attempting too many towing tasks, especially since the one and only attempted towing task resulted in the only invalid day of the meet.

In my opinion only one of the competition days was really successful even though three were officially declared "valid". (No one completed the first day's task and the fourth day's task was changed out of desperation for holding a valid meet consisting of at least three valid contests.)

One successful day out of four didn't seem too good to me - especially since the Colorado mountain/valley location was essentially ideal for hang gliding competition and the weather was quite typical for this time of the year. Being a skyting enthusiast, I could not help but speculate about what would have happened if the weather conditions had been identical but ALL of the tasks had been tow launched (particularly if the towing format had been changed slightly).

I am convinced that an all towing meet would have resulted in at least FOUR and probably FIVE successful tasks instead of ONE! In other words, a true SKYTING meet would have been FOUR to FIVE times as valid as the mountain meet was. (A mountain task on day three would have been just as invalid as the towing task was, so this really was a mountain meet.) Furthermore, the pilots would have spent FOUR or FIVE times as much time in the air! Yes, towing competition does have a real future! In fact, I will not be at all surprised if tow launching eventually dominates over mountain launching in hang gliding competation.

The main reason I came to this conclusion is that in this competition it was the over development in the mountains that prevented mountain tasks from being initiated or completed. But at least one and probably two valley or valley-mountain tasks could have been completed during every one of the days of the competition. In fact, the only reason the actual towing task was not completed (at least to the "valid" stage) was that the pilots were not adequately familiar with tow launching and the launch techniques were not adequately perfected for this for the first tow launch contest.

For those of you who are planning a towing competition in the next year or so, let me make the following suggestions based upon what I learned at the Region 4 Competition:

(1) Use at least two complete towing systems. Pilots become very frustrated waiting for hours in the launch line while the optimum conditions fade away. The launching capacity must be adequate to launch all of the competitors in less than one hour. With dual launches on two complete towing systems one should be able to launch 4 pilots every 10 minutes to an altitude of about 1500 ft. This would accommodate up to about 24 competitors.

(2) Use an open window format with a reasonable launch time limit. (In other words, "Get in line to launch whenever you want, but once you are hooked on to the towline and let someone else launch." There is a strong tendency for pilots (particularly low-experience tow pilots) to get on the towline line and wait for "optimum" while others who are willing to launch "as is" are waiting unnecessarily for their turn to launch.

(3) As far as possible, allow pilots to choose their own set-up and take-off positions. This is particularly important if the wind is light and variable or converging over the hot runway with a resident thermal overhead (as was frequently the case at the Salida airport). If pilots are allowed to launch from either end, center, or side of the runway, then no matter what the wind is doing, somebody will be able to launch.

(4) Permit any number of starts, re-starts, and relaunches. This encourages pilots to FLY instead of waiting around on the ground. Then when the conditions upstairs look good, those pilots already in the air can go for it without waiting in the launch line or sacrificing their chances of winning. If an early start puts a pilot at a disadvantage (say conditions improve later on or he falls out of the sky after leaving the airport), he can re-launch and/or re-start under the better conditions without any penalty except the time it takes to get back through the start gate.

(5) Use of an aerial start gate. This is an obvious extension of the previous rule. By having the start gate in the air no one has to wait on anybody in order to start when they want to. All that is required for a start or re-start is for the pilot to fly directly over a designated point on the ground with an altitude of less than 2000 ft (a waved flag or a radio message could be used to inform the pilot that he has made a "good start" as timed by the starting gate judge).

A simple but effective way to varify the glider's altitude above the ground is to sight the glider through a hollow tube of the right length. For example, a 1/2-inch tube 30 inches long makes a convenient altitude sighting tube for hang gliding. Any glider with a wing span near 33 ft will be at an altitude of less than 2000 ft if it appears too large to be seen through the tube. Conversely, if the whole glider can be seen through the tube, then the glider is too high for a valid start.

(6) If thermaling conditions are not possible, a large number of sled ride tasks could be counted as one distance task. (In fact, from the spectator point of view a sled ride contest is actually superior to a cross-country contest.) The format could be similar to that used previously in water towing (such as the - Is it still being held? - Cypress Garden's Contest). Any number of tasks could be devised which taken together would make as valid a test of pilot skill as XC flying. Sled riding may not be as much fun as cross country flying, but I bet most pilots will agree that it beats sitting for hours on the ground while waiting for thermaling conditions which never develop.

P.S. If thermaling conditions do occur in the middle of a sled ride contest, the rest of the slide ride contest could be postponed until an inserted XC task is finished. If fact, one could design a tow meet with the idea of having a sled ride contest in the morning and an XC contest in the afternoon. Such a contest would test all aspects of pilot skills, not just those skills associated with a particular type of flying.

P.P.S. If any of you have experience in holding a tow launch contest, how about sharing that experience with the rest of us? Get busy writing!
*
*

[Tad Eareckson]

1985/01
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SKYTING NO.33
JAN 1985
$1.25
*
1985/01-01

SKYTING
315 N. Wanda
Kingsville, TX 78363
512/592-6757

SKYTING solicits editorial material, comments, and letters. No responsibility is assumed for accuracy of material submitted. Unless noted otherwise, material published in SKYTING is in the public domain. Such material may be reproduced with credit given to the author and to SKYTING.

One year subscription:

US$12.00 (U.S., CANADA, MEXICO)
US$24.00 (All other FOREIGN)

Back issues through No. 35:

US$35.00 (U.S., CANADA, MEXICO)
US$50.00 (All other FOREIGN)
*
1985/01-02

NEW EDITORIAL POLICY AND PRICES

You may have noticed that from the beginning, SKYTING publications have all been copyrighted. The original intent behind this was to prevent portions of the publications from being taken out of context and republished in a form that could turn out to be dangerous or even fatal. The idea was to encourage pilots to either learn "all or nothing" about SKYTING before trying it. Surely pilots would opt to learn "all".

Well, the statistics appear to demonstrate that all too many pilots are learning "nothing" - or at least "not enough" - about skyting before doing it. The result has been numerous accidents and several fatalities within recent months.

In hopes that "a little knowledge is better than none" and that "free access to knowledge encourages dispersion of knowledge", I have decided to change my editorial policy by placing the future issues of SKYTING in the "public domain". This means that, except for material noted otherwise, everything printed in SKYTING belongs to "everyone" and may freely be copied and/or republished as long as credit is given to the author and to SKYTING. Of course, if a particular article in SKYTING is copyrighted by the author himself, then that author will have to be contacted before you can reproduce his work.

It is hoped that by adopting this new policy more information and more correct information will filter its way down to the pilots who need it in order to skyte safely. Now, everyone in your skyting group can legally and morally make his own copy of the SKYTING Newsletter, and you can make copies for your friends and/or for any other pilot you see skyting improperly. Perhaps this new policy and our working together can begin reversing the current trend toward increasing numbers of towing accidents. Let's pray that this is the case.

Now the bad news. Inflation has finally caught up with the SKYTING Newsletter. The cost of reproducing and mailing the Newsletter has been steadily increasing since June 1982. With the anticipated postal increase this year and the decrease in subscriptions noted recently (not to mention the decrease expected as more of you begin making your own copies instead of subscribing) it is essential that subscription rates be increased this year. The new rates are $12.00 (U.S., CANADA, MEXICO) and $24.00 (All other FOREIGN). (By the way, I hope that you foreigners do not feel that these rates reflect my own personal attitude toward you. I love you guys! They simply reflect the postal rates. It costs the same to send the Newsletter to U.S., CANADA, and MEXICO - namely $.20 per issue - while costing 4 times as much - namely $.80 per issue - to send it everywhere else.)

Donnell
*
1985/01-03

PENNSYLVANIA UPDATE

Frederick E. Mack
Pottstown, PA

It has been quite a while since I have reported on our towing in Pennsylvania. I will give you an update later in this letter.

REPRINTED ARTICLE

I have reprinted your article on Natures Laws of Hang Gliding in our club newsletter. I would like to thank you for granting permission to do so, enclosed I have sent you a copy of our newsletter as you requested.

THREADED BRIDLE

We have not made any great strides in our towing altitudes nor techniques. One of my towing partners and myself still use a sheet stopper release with an unthreading bridle. We both swear by the release and the unthreading system and have not experienced any of the problems reported in your newsletter, or the Hang Gliding Magazine. I have been slapped on the thigh while wearing shorts and received a slight welt, but not anything to deter me from using the system. The preflight and hook up is so much quicker and easier than with the skyting bridle. At times we will have only one glider set up and all five of us will use it in rotation so we all have used both systems. The other three partners usually use a standard skyting bridle with three ring releases. They still only use an auto release on the top line and release the body manually.

TOWING ON "BAD" DAYS

Our main problems getting any good tows (our best is 500 ft) is that on good days with soarable winds and/or good thermals we still travel to the mountains when we are just about guaranteed hours.

We have been breaking out the winch on hot, humid, dead wind days when we would normally not fly at all. Mostly we use the winch as a toy to play with on dead days. I still think we can get 1500 ft if we can get our act together under the right conditions.

BREAKING WEAK LINKS

Our biggest problem to date has been constant weak link breaks. I would say that we break a weak link on four out of five flights, which really gets annoying. They usually occur at 300 ft or so, when the tow line gets beyond a 45 degree angle to the winch. We don't have any tension gauge on the winch, but have plenty of stretch in the line to prevent rapid tension changes. Also the winch operator faces the towed glider and watches the pilot constantly. We use climb rate to judge tension and slow down the winch if they are climbing too rapidly, or if the yaw oscillations begin, or if the pilot spreads his legs. (Ed. Climb rate is not a very good indication of towline tension, especially in thermaling conditions.) We have found that when the yaw oscillations begin, if we reduce power a little the pilot can get it back under control. The winch operator speeds up if the glider is climbing too slowly. We don't have radio communications on the towed glider after he launches (performed by launch director before launch), I realize our system is a little crude and hope to add a voice activated boom mike soon which should help.

It still seems to me that we should be able to not break weak links so often. They seem to break while there is very little tension on the glider. (Ed. You may be breaking your weak links when your winch operator trys to keep the glider climbing after it enters sinking air. It may look like there is little tension since the glider speeds up without climbing, but in reality the tension may be quite high. You really need a constant tension device.)

We are using #18 stranded twine - we couldn't find #18 braided. Is there a difference in breaking strength? (Ed. No, they break at essentially the same value.) It will support a 170 lb pilot, then breaks with a little more pressure on his shoulders. We figured the breaking strength to be 180-190 lbs.

What do you think of using a 1G breaking strength for pilot and glider? i.e. 180 lb pilot + 70 lb glider = 250 lb weak link. A lighter pilot-glider combination would use a weaker weak link. (Ed. This is the recommended procedure for determining the weak link break point, so your current weak link is too weak.)

LOOKING FOR A LONGER STRIP

We are up to about 30 tows each and have been somewhat discouraged by our present altitude. Although we haven't worked on refinements much, we are somewhat intrigued by the reverse towing techniques now surfacing, and are presently looking for a longer towing strip where we can get out our entire 3000 ft of line and possibly add some more.

If we can tow to 1000 ft or more then release, I'm sure that thermal gains will add a new excitement to our towing and perhaps make us look to winch on good days instead of heading to the mountains. It might also encourage some refinement work during week nights to make our operation smoother and more successful.

I'll keep you posted on further developments in this area as advancements are made.

Frederick E. Mack
*
1985/01-04

ENGLISH UPDATE

by Tony and Rona
Leicester, ENGLAND

APPRECIATION

Many thanks for you last letter. We do appreciate your personal approach knowing full well how busy you are. We still feel strongly about the goings up on the line and regard your comments with great respect. We are very practical people with strong beliefs in theoretic back up. The theory side of things is not my strongest side, therefore, I rely heavily on others for support. Our new friend Edmond Potter who flies the Magic 1 is helping us with the computer programs and statistical designs. Sandy Cambell keeps us on the ball with the engineering complexities and my brother and his friend Phil keep us going to the airfield in the cold bitter winds.

BHGA

Our plight with the British Hang Gliding Association is hard and long, much as it must have been with you and the USHGA. They, the BH, have asked us to produce logged flights on tow of over 100 hours in total plus written procedures and hand book. Boy, are we busy.

WEAK LINKS

On the subject of weak-link breaks, we (or should I say I) have overcome the problem. The pull-in technique on take off should only be momentary. In an attempt to demonstrate that this is good practise to fellow flyers, I had developed a bad habit of pulling in too long, therefore, building high energy in the sail and on hitting a bump or accidentally letting the bar out too quickly resulted in a high energy lift situation, often so quick the pay-out winch failed to pay out quickly enough to reduce the energy. Result: weak link break. Many small factors combined to produce this situation, one of which is not a great problem but nonetheless is present and that is the inertia in the drum of the winch. It does take a few extra pounds of tension to start the payout.

I agree totally with your take-off method, except that if a little airspeed excess is not gained then certain older gliders have in our experience tip stalled or certainly have dropped a wing about 25 ft. We have found that just a little pull in on take off ensures good climb out, settling down at around 50 ft when full conversion to prone is made. We have also increased the weak link to 180 lb or 200 lb which does make everyone happier.

POTTER'S FINDINGS

Yes, Donnell, I do apologize for not enclosing Edmond's findings Find them enclosed in this letter. They got mislaid for a while. He is also at present working on some new information.

BEGINNER TOWING

More about us. You will remember it was my desire to teach pilots from scratch on a towline. Well, with that goes all the usual problems in teaching a person to become airborn, plus great restrictions from established bodies such as the BHGA and the Civil Aviation Authority. Well, nearly a year has passed and 20 new pilots are occasionally in the air over East Anglia. This is nothing to shout about, but in doing this (I suppose rather risky thing, i.e. teaching abanitio) we have developed an excellent teaching method that is not without its dangers, of course. The training officer of the BHGA became intereted and we talked and demonstrated our system. He is very impressed but very little has been done since. What I have to say is this: I realize that abanitio training is very difficult and should be handled by those well versed in it, however, someone has to realise what a wonderful opportunity towing offers for teaching. With a properly integrated program, training could be far quicker and far more effective.

For instance, we now no longer off abanitio training, but what we do do is offer an introductory plan which is designed to give a student experience in the air, to learn safely the control of a glider and to decide whether he or she wishes to continue. If they do, then the second stage would be on the hill with an approved schooling method. The school would be well aware of the preliminary work done by the student in free flight having already gained aircraft control abilities. This would greatly improve student training and membership in Hang Gliding. Once the student had mastered freeflying, he would then be free to return to the towline to gain more experience and to improve his flying capabilities including spot landings, etc.

PULLING IN

Back to Skyting No.29 in which Doug Gordon states No. 3 pull in pull in. This could have the effect of my problem and lead to a horrid yawing speed wobble situation. We had experience of this only last Sunday. A pilot who had been unnerved due to a hill crash insisted upon pulling in and over reacting, eventually resulting in a horrid downwind turn after tension release.

We actually push out a little if the glider starts to yaw. This has the effect of increasing the tension in the sail and stabalizes the roll and yaw. I relly feel that if Doug Gordon is having to stress the pull in syndrom so greatly then his attachment point to his glider must be far too near the static balance point of the glider's keel. I suggest he move the tow point forward or reviews the system he is using. We do not have to pull in at all in the climb out (unless the kite gets hit by gusts) and, although very little appears to be against it, if the bar is pushed out to the fullest limit on a pay out system the glider remains stable. I feel this would be the same on a pressure indicated fixed line system. We find a little push out does give greater drag but higher climb rate. Personally, I prefer to climb at about 18-20 mph.

DRAGGING A TOWLINE

At high altitude release failure I feel it is necessary for the pilot to be aware of procedures for landing. We used to use 360 degree turns to come down, but we have since changed this to "S" turns, made shallow and with care, watching the line as you manouver. 360 degree turns put one wing very low and risks looping the line over the tip. This is definitely a NO, NO.

SHORT THREADER

I feel the need to say this about anything that can happen will happen eventually. So bearing this in mind, avoid using cords and ropes that dangle or whip around where possible. I especially mean this in reference to the "threader." We have as shortened version of this system which works well but if there is a way to reduce the use of it we would use it.

The use of the tow leg has improved the system as has the incorporation of the belly cord to the harness with the back-up release. However, we feel even the belly cord could get tangled and, in consequence, I am stiffening it as a prevention against the possibility.

CROSS WIND

Yes, we are doing 90 degree take offs using a side runner. It works very well. Also, in stronger winds we use wire and nose men in take off situations similar to the hill.

INTEREST INCREASING

On a lighter note: The skyting program in England is on the improve. We are getting more and more interest as time goes on. Another team in Durham City, 200 miles north, have just begun. Having spent some time with us, they decided they liked it enough to build their own winch and do some towing of their own.

FOOTNOTE

A foot not I forgot to mention: Have you had any letters describing either the porpoise/dolphin effect or bad thermal interference whilst on tow?

PORPOISE OR DOLPHIN EFFECT

Porpoising or dolphin is an effect which will happen on tow if the attitude of climb is incorrect. The Lake Bridle does demonstrate this feature. The glider appears to mush and then speed up and climb again. This oscillation is not desirable and if experienced, the remedy is to pull on some speed and release. It usually occurs at high line angles, and there will be little height to gain from then on.

Apparently the sail plane boys have experienced this and say it is quite normal as an experience, that is quickly remedied by stick forward a little.

The oscillation has resulted in excessive wear at the junction of cross bars to keel, in the bolt holes which have become ovaled. I have since checked over the kite and replaced the faultered sections. The Lake Bridle is excellent for training as it is so simple. For repeated tows for experienced pilots, I do not recommend it. The bridle is brilliant to line angles of 45 degrees, but no greater. We always return to the Skyting Threader System!!

THERMAL INTERFERENCE

The sailplane boys asked a horrid question the other day, "How does a hang glider react to being inverted by a thermal on tow?"

Personally the thought fills me with horror and an ever great desire to get a parachute. I don't believe a hang glider would behave very well being inverted in any situation.

I have been towed through some pretty tough thermals. Apart from being scared of being caught between lift of 7 to 8 up and a line pulling me down everything seemed to be well. I was glad the release worked. I didn't cherish the idea of waiting for the weak link to break, or being lifted even higher with 2000 ft of line dangling below, having pulled free from the drum (which incidently it is designed to do).

In fact, while skyting 2 weeks ago Rona climbed to 1500 ft and took the line completely off the drum. She experienced the equivalent of a high tension break. She quickly pulled in and recovered to free flight, then released the line. She had 7 minutes in the air - 4 min on tow. The wind was strong and she had to fly rather fast to prevent herself from being blown downwind of the airfield, which accounted for why the free flight was shortened.
+
Climb path
Mush Point
Nose angle of attack Reduced result in increase airspeed.
*
CONVERSATION WITH SOUTH AFRICA
*
1985/01-05

Dear Donnell:

HEWETT BRIDLE

Once again thank you for your prompt and most informative response. The latest skyting info is very interesting and does answer a number of questions. Sorry the question that you did not understand needs some explanation though I do not feel that it is of any great importance. In the normal H.B. the lower half of the bridle (i.e. the part that passes through the ring attached to the main hang straps of the harness) passes through the lower ring and then back to the tow rope to which it is attached. It is thus able to slide through this ring as your angle of tow changes. The system that we tried had the bridle attached to the harness hang straps, the release at the keel, the bridle thus remaining on the harness after release. This was just gathered up and stuffed into the cocoon. The lower bridle thus could not slide through a body ring as the angle of attack changed. The bridle passed through a ring that attached to the tow rope. This ring would thus slide up or down the bridle as the angle of attack changed. This solves your second question about the sliding ring and, hopefully the confusion.

GETTING INTO THE COCOON

I have a few questions regarding the tow training techniques describe in No.28. I have never had problems with my cocoon harness. A loop on the boot is passed over my left wrist and is thus only released when moving one's hand from the down tubes to the control bar. The harness is a bit difficult to get into if one does not climb in immediately after takeoff (t/o) as it gets pulled forwards. At high tow angles, I first put my one knee in, pushing my boot back enough to get my other foot in followed by a mighty heave for the first foot. This technique is for the shoulder bridle.

NO NOSE-UP PROBLEM

Another thing - I never found that the glider's nose had any tendency to pitch up. I did find it a bit uncomfortable standing ready to launch with a higher than normal angle of attack. This is accentuated by the fact that the altitude and sites we normally fly require a really good run on launch (mountain flying).

WHY SHUFFLE?

I don't understand the shuffle. I have always given it a good run. I suppose one would use this for strong wind launches which is not very common here. Your description/explanation of the shoulder towing techninque, No. 26, is most enlightening and interesting and makes me feel a lot happier about using it. We started aerotowing in +/- May using Trevenot's ((Thevenot's)) Cosos ((Cosmos)) Trike and system and had great success. That is why we tried skyting using the shoulder bridle.

DUAL TOWING

We have tried dual towing, i.e. two pilots to one glider, and it went off very successfully. An almighty run was required as there was not much wind which resulted in many jokes afterwards with stories of 10m strides followed by flapping into harness from exhaustion, the glider sinking down to earth and then slowly rising for a successful flight.

ACCIDENTS

A couple of weekends ago we went down to the gliding club in Welkam to tow on their runway and hitch a ride in a glider. The skyting was not very successful as only 3 guys got away. It was a very frustrating weekend as there were 9 pilots and one tow car and a couple of guys were novices.

I got pretty desperate on Sunday. The wind was strong at 90 degrees to the runway. I waited until I could hold the wings level and gave the command. I had a flawless t/o after a good run and was just swinging into prone when the glider started sinking. I remained upright ready to run again (which, of course, would not really have been possible due to the speed). The glider recovered and the process repeated itself. Things did not feel right so I looked down the towline to see it caught in a small anthill. I was about 3m off the ground and could just visualze myself ploughing into this anthill and the ground. I released and turned into wind as I realized the glider would be in a stall situation. Well, I bent one downtube and carried/hauled my glider back to t/o in a fit of rage. I had been assured by the driver before I launched that the towline was not tangled in anything. And if I had been towed on up I am sure that I would have got away.

Anyway, I went for a winch launch in a sailplane and had a very enjoyable thermaling flight marvelling at the performance of proper gliders.

We had three accidents that weekend: mine and 2 stalls on t/o caused by too high an angle of attack, the glider attempting to fly initially, stalling a wing and nosing in, bending a couple of down tubes, totally unnecessary. All flights were done using the shoulder towing technique.

Paul Thomas
Johannesburg
SOUTH AFRICA
*
1985/01-06

Dear Paul,

HEWETT BRIDLE

Thanks for writing and trying to explain what type of Hewett Bridle system you were using when you began skyting. But we seem to having some sort of communication gap. I am sorry, but I still do not understand what kind of Hewett Bridle configuration you are referring to. Is it as illustrated below?
+
2:1 Skyting Bridle
+
Threaded Release
+
If so, then this is a threaded-bridle release system with a body extension line which stays with the pilot upon release. If not, then I still cannot picture the design you were using. Sorry to be so dense, but if the above is not the correct design, how about drawing me a picture of your design.

I know that you do not consider a discussion of this bridle to be very important since you no longer use it, but I am very curious as to exactly what you were using. After all, doesn't it seem appropriate for Hewett to understand what a "Hewett Bridle" is?

SHUFFLING

Now in answer to your questions. Remember that most pilots attach the body line to their cocoon at the bottom of their hang straps instead of at their shoulders. (Of course, your letter about the practical advantages of shoulder towing may encourage more pilots to try shoulder towing.) Therefore, holding the boot up during takeoff can, at times, interfere with the bottom bridle line. This is why they stuff the boot between their legs and shuffle their feet on takeoff.

Another reason to shuffle one's feet - even if the boot does not get in the way - is to keep from running too fast. You may have noticed that a pilot with glider can accelerate faster than the car if he tries a conventional hard running takeoff. When towing, this can produce a slack line. The pilot then finds himself running hard with too little tension to take off. There is a good chance he will lose his balance and fall before the car accelerates enough for takeoff. Even if he doesn't lose his balance, when the line becomes tight the car will probably be going so fast that it will become too tight and produce a catapulted launch. By shuffling one's feet it becomes impossible to out run the car. The tension smoothly builds up and a smooth takeoff results.Personally, I am like you - I prefer to be able to run at full stride if the situation requires it. Since I don't fly with a cocoon, I have not made any firm decisions about which cocoon towing method I like best.

INTO COCOON

Pilots who tow from their hang straps do not have the trouble you have with the cocoon being pulled up so it is harder than normal to step into. I am glad you shared your technique with us so those who try shoulder towing will not have to discover the technique for themselves.

NOSE-UP

The reasons other pilots experience a strong nose-up tendancy on takeoff are (1) they run the body line UNDER the control bar, (2) they tow too FAST, and (3) the nose attitude of towing APPEARS too high to pilots experienced only with free-flight. You do not experience case (1) with your body line running THROUGH the control bar. Apparently you have not yet had the pleasure of flying with a really HOT driver on takeoff or you would have experienced case (2). And as far as case (3) is concerned, you mentioned that you have already experienced at least one form of that.

DOUBLE TOWING

I was glad to hear that you were able to double tow successfully. Not only is this fun, but there is also potential here for a one-on-one towing competition format. Who knows what the future holds.

ACCIDENTS

I was sorry to hear about the accidents you reported. Tow rope snagging on the ground is a real possibility, especially in a cross-wind situation and it can happen well after everything gets moving, so don't be too hard on your crew - in might not have been their fault.

Thanks again for keeping us posted on your progress. We are not only interested in what is happening in South Africa, but we are also interested in hearing how the shoulder towing technique is working out.

Donnell Hewett
*
1985/01-07

Dear Donnell,

HEWETT BRIDLE

All this confusion! Thanks for your prompt reply. I have a number of things to comment on.
+
1:1 Skyting Bridle
+
Release
+
This is the system that I have used. The bridle was released at the keel and then remained attached to my harness. I.e. it was not threaded through a couple of rings, only one on the towline.

SHUFFLING

As regards shuffling with a cocoon. Our t/o technique may be different. The driver pulls away as fast as possible and then controls his speed according to the tension gauge. Most of our towing has been done with a front wheel drive Opel Kadet on a sandy surface which requires careful driving to get a good pull away. The pilot resists the pull for as long as he can/feels comfortable and then starts running. I have never out run the car and have thus never lost balance. One will only lose balance if the glider is not supporting its own weight. I am sure that if you stumble whilst running, the glider will support you enough to regain your balance and continue provided of course that the glider is supporting its own weight. The glider is inherently stable on a tow takeoff and has a lower stall speed due to ground effect - this is one of the safety features of skyting. On t/o I prefer to run a pace or two extra before easing the bar out a bit to get flying.

DUAL TOWING

There seems to be a misunderstanding with dual towing. We have not tried towing two gliders. This is something that I am really keen to try. Just thinking on it one would attach the tow ropes to separate points on the car each with its own tension gauge or else use a stronger spring. Would one tow at double the glider's tension then. By dual towing I meant two pilots to one glider.

Paul Thomas
*
1985/01-08

Dear Paul,

HEWETT BRIDLE

Thanks for writing and illustrating the bridle you were using. It is now much clearer why your "Hewett Bridle" produced more adverse yaw than normally experienced by myself and others. You are using what I would call a 1:1 skyting bridle, which distributes equal forces to the pilot and the glider's floating keel. This is not a very good approximation to the center-of-mass towing concept which requires the towing force to be distributed between pilot and glider proportional to the weights of each. Ideally the skyting bridle should be more like 3:1, but in practice most pilots use a 2:1 arrangement as shown in my previous letter.

This places twice the towing force on the pilot as on the keel and reduces the adverse yaw tendency.

By the way, I still do not see how you use a 2-ring release with the threaded bridle without snagging on one of the rings or popping yourself hard as it unthreads on release. Most pilots use a sheet stopper as illustrated in SKYTING No. 25.

Your takeoff sounds quite similar to that used by many other pilots.

DUAL AND DOUBLE TOWING

Sorry about the confusion about "dual towing". You are right. In general aviation, dual flight means two persons in the same aircraft. However, in the USA the word "tandem" is commonly used to refer to "dual" hang gliding.

I know that "tandem" really means the one-in-front-of-the-other, and that two persons on a hang glider are not really in tandem, but because others use the word this way, I tend to do the same. I, therefore, tend to associate "dual" towing with what should more appropriately be called "double" towing.

Double towing is really fun. When we did it, we attached the tension gauge to the heavier pilot-glider system who was also on a towline about 100 ft longer than the light system. This made it impossible for the two gliders to collide on tow. Both pilots took off simultaneously separated sideways by about 150 ft (obviously both pilots were experienced skyters). I, the lighter pilot, climbed faster and could always see "Red", the heavier pilot, on the longer rope beneath me. "Red" could see me in front and above him. We climbed steadily, maintaining our separation, and ready to release and turn away from the other if anything went wrong. Nothing went wrong. (Well, "Red" did break his weak link once or twice, but when this happened, I simply released and landed so we could both get ready for the next flight.)

Donnell Hewett
*
1985/01-09

COMPLETE SKYTING BRIDLE AVAILABLE

Southern Nevada Soaring Supplies, has developed a three-ring, apex release bridle (which stays with the glider after release). It comes complete with harness and glider attachments. No extra hardware is needed.

The glider attachment is covered with clear tubing to reduce wear. The large ring of the three-ring release is attached by a short piece of webbing to a small D-ring which may easily be tied to the towline. The release and harness attachments are made of 2 inch nylon webbing. The bridle is made of 1/4 inch polypro. All eyelets are fitted with 1/4 inch thimbles for less wear and longer bridle life.

The complete bridle assembly sells for $45.00 (3-ring release only $35.00), which includes postage and handling. For more information contact Rolla Manning, P.O. Box 238, Logandale, Nevada 89021.
*
1985/01-10

DIPOLE CB ANTENNA AVAILABLE

Southern Nevada Soaring Supplies has also announced the availability of a dipole CB antenna for the Radio Shack 5 watt, 6 or 40 channel CB.

It is light weight, easy to install and folds up with the sail. You do not have the hassle of putting it on every time you set up to fly. It has a built in weak link. If you snag a bush on landing or final approach, you simply plug that lead back in. If you damage any part of the antenna, you do not have to throw the whole antenna away. The three piece unit can be bought separately.

The whole package sells for $20.00. That includes postage and handling. For more information contact Rolla Manning, P.O. Box 238, Logandale, Nevada 89021.
*
*

[Tad Eareckson]

1985/02
*
SKYTING NO.34
FEB 1985
*
1985/02-01

BIGGER AND BETTER

You may have noticed that the SKYTING Newsletter is getting bigger (8 pages long instead of the usual 6 pages). If you keep sending me more material than I can print each month, I will eventually have to start being more selective in my editing. Conversely, if you stop sending in material, I'll have to drop back to the 6 page newsletter.

Things are also getting better. Thanks to USHGA, aero-towing is now legal in the U.S.A. (as long as certain conditions are met). But be sure to follow the law, or you could still be fined by the FAA. More about this next month.
*
1985/02-02

SERIOUS CANADIAN ACCIDENT

by Timothy P. Churchill
Lower Sackville
Nova Scotia, CANADA

I am writing to report a tragic accident which occured here in Nova Scotia this past summer. A novice pilot named Andre, suffered a broken leg, dislocated hip, fractured pelvis, and worst of all, severe head injuries when his Pheonix 6-C apparently locked out at approximately 75 feet. Andre's bones have since healed without the need of surgery but the damage to his brain will probably be with him for the rest of his life. His condition was described by the doctors as commatose with a 25 percent chance of total recovery. Perhaps a prayer or two from other pilots may serve to tip the scales a little more in his favor.

The accident occured at a popular towing site in our area known as Grand Pre'. The weather conditions were good with a light wind and clear skies. Prior to the accident Andre had towed me up five times resulting in five excellent flights and no apparent problems with the threaded bridle. The radios we normally use had to be discarded as the van we were towing with proved to be an excellent barrier for radio waves. Andre's decision to fly was made only after another local pilot and his girlfriend showed up and assisted with ground handling and coaxing ((Coaching?)) while I towed with the van. Upon receiving the go signal I accelerated to about 20 mph and watched out the window as Andre lifted off and climbed smoothly to about 50 ft. At this point he went prone. The glider then banked to the right and believing the turn was little more than a yaw caused by the transition to prone, I continued to tow and waited for the correction. The turn continued and the bank increased to the point where it became obvious something was definitely wrong. I immediately stopped the van and hoped the towline would go slack and allow Andre to level the glider. Passing to the right of the van, the glider continued the high banked turn until it hit the ground practically in a vertical dive.

As only Andre could tell us what actually went amiss, I have been hesitating writing this letter in the hope he would answer all the unanswered questions. Failing this, I will offer my hypothesis as well as the ground crew's.

1. Tow bridle became tangled on bolt extruding through base tube. The bolt was used to attach an extra tube to the base tube for the addition of floats/wheels. As this is the most likely cause I would caution all tow pilots to examine their base tubes for any objects which may tangle with the tow bridle. Andre was seen to move to the right in an apparent attempt to untangle something.

2. Structural failure, the Phoenix was known for bending side deflexor posts. As the glider was totally destroyed, this cannot be proven.

3. Pilot was unable to correct the flight path because of lack of experience or fright. I believe this was his highest flight.

In closing, I would like to warn tow pilots to take care not to throw caution to the wind.

-

ACCIDENT SUMMARY

DATE: July 14, 1984
SITE: Grand Pre dykes, Annapolis Valley, Nova Scotia
SYSTEM: Towing with center-of-mass bridle, threaded release, approximately 700 ft towline with 150 lb weak link.
GLIDER: Phoenix 6C
CONDITIONS: Clear sky, west wind at 5 to 10 mph
PILOT SKILL: Beginner, approx. six months.
DESCRIPTION: After a good takeoff and initial climb out to about 50 ft, the pilot went prone. Apparently the towline tangled on a bolt extruding through the base tube. Pilot was seen making several attempts to free towline with no success. Glider banked to the right in a lockout which continued all the way into the ground. Witnesses said that pilot seemed to hit the ground head first and were it not for his helmet he would have most certainly died. After the accident great care was taken to insure he was comfortable and was not moved in case of back or neck injury. An ambulance was summoned almost immediately and he was rushed to a local hospital and shortly thereafter to Halifax.
GLIDER DAMAGE: Totaled.
PILOT INJURIES: Broken right femer bone (2 places), fractured pelvic bone (several places), dislocated hip (right), brain damage.

LESSONS:

1. Van used in towing made radio communication impossible due to metal.

2. Releasing from the towline was not instinctive to pilot due to lack of experience.

3. Bolts used to fasten wheel axle to base tube were not recognized as a hazard.
*
1985/02-03

SUPPLEMENT TO ABOVE ACCIDENT

by Tom Bushell
Halifax
Nova Scotia, CANADA

I am filing this report to clarify a few points in Tim's report. I was not a witness at this accident - this is based on conversations with witnesses Tim Churchill and Greg Sundstrom.

PILOT EXPERIENCE

Andre had bought his glider from Tim Churchill, a Level 2 pilot. Because we have no qualified instructors in this area, Tim was giving Andre what help he could when they went out together. Tim had flown with Andre three or four times, flying tow each time. It's probable that Andre had had no more than 20 flights. He had also tried going out by himself in a strong wind to try kiting the glider. He was unable to ground handle the glider, got blown over, and damaged the glider substantially. Tim said he was "agressive".

MODIFICATIONS TO GLIDER

When Tim had owned the glider, he had attached floats by bolting another tube to the bottom of the basetube. He had not cut off the protruding ends of the bolts, so they projected below the bottom of this second tube. Tim flew the glider in this configuration for several months, using a skyting bridle with 3-ring releases and 1/4" yacht braid, with no problems. When Andre bought the glider, he left this tube attached, and put training wheels on the projecting ends.

BRIDLE

Tim had lost his 3-ring bridle, and had been using a threaded bridle, similar to those described in Skyting newsletter #23. This bridle was made from 1/8" nylon towline, and had a loop knotted in the end for the release. The release was a "loop and pin" type as described in Skyting #25.

WEAK LINK

Also, they may have been using a doubled weak link (4 strands of #18 nylon twine) - Tim had flown with a doubled weak link on previous occasions. He was unsure what they had been using when I quizzed him on this point.

THE ACCIDENT

They had a pair of FM headset radios for pilot-driver communication which had a history of being unreliable, and weren't working on this occasion. So, there was no communication between pilot and driver. They chose to fly anyway. There was a potential observer for the tow vehicle (Andre's girlfriend) but apparantly this wasn't considered.

Tim had several successful flights on his Raven. Then Andre had a couple of low level flights. About this time, Greg Sundstrom arrived - he witnessed the final flight.

When Andre launched again, Greg said that the part of the bridle that passes under the base tube folded on one of the protruding bolts. Instead of releasing, Andre made several attempts to free the bridle. Meanwhile, the glider started to drift to one side. Tim, having no way to know what was happening, accelerated the tow vehicle. The glider locked out and dove in from 100 ft. Andre tried to release, without success, and the glider accelerated into the ground. Greg said he thought the weak link should have broken long before the glider reached that speed, which makes me suspect that they may have been using an overstrength weak link, or none at all.

PILOT'S PRESENT CONDITION

Andre spent several weeks in a coma, but eventually revived. He suffered severe mental impairment, but was slowly recovering. He has since returned to Quebec and we have lost touch with him.

CAUSE OF ACCIDENT

As is so often the case, this accident seems to have been the result of a number of factors:

1. The bolts through the base tube snagged the bridle, and forced the glider into a lockout. Donnell Hewett has stated several times in the Skyting newsletter that the bridle must not touch any part of the glider except the attachment point. Unfortunately, no one, myself included, had recognized that these protruding bolts were a hazard, as the glider had been flown several months without incident.

2. The release failed under emergency conditions. Doug Gordon describes problems with this type of release in Skyting #27.

3. In my opinion, it was a serious lapse in judgement to fly without an observer in the tow vehicle. It's possible that an observer would have seen what was happening, and told the driver to stop.

4. The threaded bridle may have been more prone to foul, because it used much thinner line than the 3-ring bridle previously used.

5. The pilot was very inexperienced. I don't think anyone at this level should be flying at high altitudes.

CONCLUSION

The main cause of this accident seems to have been the equipment. It is imperative that the bridle be free to slide along the bottom of the base tube. This means that wheels, speedbars etc., are potentially dangerous. If you tow with this type of equipment, make a bridle check part of your pre-launch checks.

This accident points out the importance of well built, well tested equipment. Use only proven gear, and test EVERYTHING as much as possible on the ground before flying with it.

In conclusion, I think this accident resulted mainly from faulty gear and sloppy safety practices. It's especially unfortunate since the senior pilot on the scene, Tim Churchill, is a subscriber to the Skyting newsletter, and could have avoided some of these errors if he had been more familiar with the material. Personally, after dozens of flghts on the Skyting tow system, I have the utmost confidence in it. I believe that with proper equipment and training, it is as safe or safer than foot launching.

*
1985/02-04

DONNELL HEWETT NOMINATED FOR AWARD

Dear Donnell,

Got No. 32 and have finally read it. Your editorial re: USHGA was right on the mark. Tho Whole Air has promoted towing extensively, USHGA has never truly followed suit. Why not?!? You though, Donnell, are about to be celebrated through the Association. I nominated you for a recognition award (for your tireless efforts on behalf of safe towing) and I believe you will receive the award. You certainly deserve it!

Dan Johnson
Lookout Mountain, TN
*
1985/02-05

THE PAY-OUT WINCH METHOD OF LAUNCHING HANG GLIDERS
-some theoretical considerations

by Edmund Potter
Bruwell, Cambridge
ENGLAND

PART 1. INTRODUCTION AND STEADY FREE FLIGHT

1. INTRODUCTION

1.1 The Value of tow launching

Opening up the flatlands

For hang glider pilots living in the flatlands, the need to travel to the hills and to guess the wind direction in advance can be a very expensive and frustrating aspect of the sport.

If a successful and safe tow launching method could be established then significant extra areas of the country would be opened up for flying, and the pressure on existing hill sites would be eased.

The flatlands often enjoy better and more predictable weather than the hill regions, and if an airfield or two or three runways is available then flying can often proceed irrespective of the wind direction.

Training

Tow launching provides qualified pilots with an opportunity to gain experience in smooth air with plenty of altitude and airspace. If agreed procedures could be worked out there would be no difficulty in ab-initio training although there would obviously be a need for flying experience from hills.

Test flying

The ability to be launched to about 1000 feet in smooth air and fly back to the take-off point ready for another launch in just 10 minutes after taking off may well be attractive to manufacturers and other people involved in flight testing.

Conclusion

Tow launching has a lot of potential for improving all aspects of hang gliding.

1.2 The purpose of the report

A rational basis for tow launching procedures

During the course of a tow launch, many of the factors affecting the height achieved are impossible to measure and may well be changing all the time. A mathematical model however can fix all the variables execpt one and investigate the resulting changes.

Not only is this simplification possible but the actual magnitudes of the changes can be calculated. So, for example, the effect of increasing towline tension by a certain amount could be evaluated in advance.

WARNING!

The calculations DO NOT determine whether the hang glider under tow is STABLE! Stability calculations would be extremely complex and would need hang glider data that are not currently available.

1.3 Outline of the theoretical approach

First of all the flight regime of a hang glider in free flight is established. By means of the flight polar and some experimental results for angles of incidence the flight variables of speed and altitude can be determined throughout the practical speed range.

Next, the effect of attaching a towline to the hang glider is evaluated. The effect of towline tension and inclination on the speed, altitude, and climb rate of the glider can be determined.

Finally, a mathematical model of the tow launch is used to find the height obtained by the hang glider at the end of the launch. Factors such as the length of the runway, headwind, and towline tension can be varied to optimize the height obtained.

Assumptions

Certain simplifying assumptions have to be made to keep the mathematics manageable! The flight is STEADY, with NO ACCELERATIONS.

2. THE STEADY FREE FLIGHT REGIME

The exact equations for free flight are derived in Appendix A. This enables the glide angle (Beta), the true airspeed (VL) and the altitude (ATT) to be related to values of lift coefficient (CL), drag coefficient (CD), and the angle of incidence (Alpha) for a specific hang glider.

CD can be derived from the flight polar curve (Appendix B). Values for the angle of incidence relative to these lift and drag coefficients were measured in flight using a homemade device. (Appendix C.).

The angle of incidence datum is the undersurface of the wing, not the keel. This gives angles approximately 6 degrees less than those specified relative to the keel.

The complete set of values is brought together in Table 1. They apply to a Magic 1 (165) with a light weight pilot (140 lb) and are in reasonable agreement with actual flying experience.

The zero angle of incidence figures are included for theoretical interest only. In practice, even with a speed bar, it is difficult for a light weight pilot to fly faster than 40 mph on this hang glider.

Best glide angle occurs for Alpha = 16 degrees; and at Alpha = 30 degrees the wing is beginning to stall.

Combining the above figures with a practical knowledge of the pilot's body position during flight allows the diagrams in Fig. 1-4 to be constructed. The velocity vector is shown diagramatically in these figures.
+
APPENDIX A.

EXACT EQUATIONS FOR FREE FLIGHT

AIRFOIL DATUM
HORIZON
GLIDE PATH
L
D
W
a degrees
B degrees

a = ANGLE OF INCIDENCE
B = GLIDE ANGLE

For steady flight, the forces must pass through one point and be in equilibrium.

'Attitude' is defined is the angle of the airfoil datum w.r.t. the horizontal i.e. 'ATT' = (a-B)degrees

For consistent units:
L, D, W: lbf (lb wt)
p (Air density): slug/ft cubed
S (Kite wing area): ft squared
V, Vv, Vh: ft/s
+
FREE FLIGHT
TABLE 1
+
APPENDIX B.

FLIGHT POLAR FOR MAGIC 1 (165)
POLAR FOR MAGIC 1 (165)
AND IN-FLIGHT ANGLE OF INCIDENCE MEASUREMENTS.
(BASED ON ALL-UP WEIGHT = 210 LB. WT.)
DERIVED FROM GERMAN POLAR FOR MAGIC 3 (166)
HORIZONTAL SPEED
VERTICAL SPEED
+
FREE FLIGHT ATTITUDES
(SEE TABLE 1)
+
Fig 1

NEAR STALL
a=30 degrees
+
Fig 2

MIN. SINK
a=19 degrees
+
Fig 3

BEST GLIDE
a=16 degrees
+
Fig 4

MAX SPEED
a=5 degrees
+
APPENDIX C.

ANGLE OF INCIDENCE MEASUREMENTS FOR MAGIC 1 (165)
ANGLE OF ATTACK (INCIDENCE) vs AIRSPEED FOR MAGIC 1 (165)
ANGLE OF ATTACK (INCIDENCE)
(AIRFOIL DATUM)
KEEL DATUM
TRUE/INDICATED AIRSPEED CONVERSION FROM 'HANG GLIDING TECHNIQUES'
DENNIS PAGEN P41
*
1985/02-06

TOW CONTESTS - A NEW DIRECTION

by Denis Cummings
Singleton, AUSTRALIA

About 18 months ago, a new method of car driven, tow launching for hang gliders was being developed in this country. (See Skyting #17.) The system stems from Donnell Hewett's "Skyting" techniques, and from the trial and evaluation of the various minor refinements. Even today, Donnell's "Skyting Criteria" still hold true and the only changes made have been in the minor details.

After sampling the may advantages of launching "from the bottom" and the excellent cross-country soaring of the inland N.S.W. "flatlands", I decided to run a tow-launched competition.

This resulted in "The 1984/85 Flatlands Hang Gliding Cross Country Challange", a contest and seminar, which was held at Parkes, N.S.W., over the X-mas and New Year. About 60 pilots attended and flew (many had their first tow launches), while 25 pilots competed in the "Challange". A separate report on this contest will appear in a future issue of this newsletter.

The "Flatlands" was a trial of tow launching for contest purposes. It was successful in the following areas:

1. You CAN launch a large number of pilots in a relatively short time.

2. If thermals are around, pilots can usually "get away" after 1 or 2 tows. Unsuccessful pilots can keep on trying. (We regularly got the whole field away.)

3. Launching from 1 central site can be carried out in winds of ALL directions and of all safe strengths. (Generally wind strengths can be much greater than are considered safe for hill launching.)

4. Selection of tasks is made easy, once the day's weather conditions are known. The limitations of terrain, which hamper a lot of "hill launch" contests, does not exist in the well populated agricultural areas.

The contest showed us the following points:-

1. The contest site must be suitable.

2. There must be enough tow vehicles and drivers.

3. Pilots, drivers, et al., must CO-OPERATE at the launch to ensure sooth launching.

4. Pilots must be PREPARED for tow launching at preferably EXPERIENCED at tow launching. (All pilots who completed the 10-day contest were experienced and prepared by the end of the competition.)

Let's look at the requirements in detail.

LAUNCH SITE

A large, cleared paddock or field is needed. (We had a wheat paddock, with the stubble left.) because surface winds play a large part in successful multi-launches, the paddock must be able to have lanes, of at least 1 km length, in about 4 directions. (i.e. N/S, E/W, SE/NW, and SW/NE). For lighter winds, at least two perpendicular strip directions should be 1.5 km or longer (e.g. the N/S and E/W strips). If the contest is to have a large number of competitors, there must be sufficient, marked driving strips for each tow car. I suggest that 6 pilots per tow car is excellent; 8 or 10 pilots per car could be too crowded on "scratchy" days. Strip or lane spacings should be such that the MAXIMUM distance between strips is obtained. 40/50 metres should be considered as MINIMUM spacing. Fig. 1 shows a good layout for a 1.6 x 1.0 km paddock.

Generally, the longest strip direction will be used when winds are "light and variable" (very common in central N.S.W.), or up to 10 mph while within 45 degrees of the strip. Any "prevailing" wind would dictate "prevailing" wind would dictate which end to use. When the wind crosses more than 45 degrees and is greater than 8 to 10 mph., then the longest strip, closest to the wind direction, should be used. Only when the wind is greater than 15 mph, and the direction is right for the shorter, 1.0 km strip(s), should these be used. However, under these conditions, they are NECESSARY.

These strip lengths will generally ensure that tows (using 1600/1800 ft - 500/600 metres of tow rope) will launch pilots to at least 1000 ft - 300 metres under usual tow conditions. Other possible paddock layouts could be used, utilizing available land area, as long as there is some flexibility for winds expected and encountered. All paddock area used must be clear of rope-catching obstructions, to allow unhindered rope return.

Having all strips in one paddock is preferable to having to use different paddocks for different strip directions. As strips of different directions will usually cross each other, it is usual to get pilots and drivers together before each day's start, to agree on the strips which are to be used. Strip direction changes, once the day has started, can be annoying.

TOW VEHICLE AND DRIVERS

Here experienced drivers will help. If drivers are not experienced, they must be trained to tow accurately and efficiently, and to "manage" their tow rope returns. An observer can assist - not to observe the pilot, but to watch out for adjacent tow cars, ropes, and pilots who are flying free. He/she can also record pilot's names and tow release times, help with any rope handling, etc.

Rope returns can be done easily and efficiently if the driver doesn't try to "manhandle" the rope, but rather "drives" the rope back into position. This is assisted by the use on each rope of two "weak links" and two "leaders", and the direct return of the car to the next pilot. The car is hooked up to the main rope only on its return to the towing end. (The unused leader/weak link is usually attached loosely at the back of the car.)

In the case of rope breaks, again, "driving" the two tow rope pieces back into position is usually the fastest.

Driver have the job of laying out the rope each morning, checking ropes, leaders, weak links, gauges, etc. before the day's towing.

LAUNCH CO-OPERATION

Pilots must assist drivers, and each other, to prepare for launch. Sometimes a driver needs a hand to lay out rope, check gauges, etc. Pilots can assist fellow pilots with hang checks, clip-on checks, etc. On windy days, a bit of kite-handling help is often needed.

PILOT PREPARATION & EXPERIENCE

Each pilot must have his own bridle and a good radio. At Parkes, we used up to 6 CB channels for tow car/glider communication. However, we found that "close" channels gave minor interference. For future large contests, it will probably be necessary to have a 40-channel set to make the best use of the radios. Channel 10/14 (27.625 MHz) was used exclusively for Start/Turnpoint/Finish notification.

Any pilots who experienced radio malfunction or who weren't ready when the rope arrived, had to step out-of-line, repair and/or get ready, and re-enter at the rear of the waiting line. Very few pilots ever had to move out of line.

As a transmitting radio can hold up subsequent launches, we started out by offering pilots a severe penalty for not "releasing" transmission at the end of their tow. To aid pilots, they were requested to report to their drivers - "Released rope, clipping off mike, thanks for the tow." Nobody had to be penalized!!! Pilots then usually switched to the Competition Channel (10/14).

Initially, pilots were reluctant to start their launch unless the wind was directly in their face. As they gained launch experience, they found that the main criteria for a safe launch start was that they could, in a steady, relaxed manner, support their glider level, and with the correct pitch angle. Delays due to wind direction were eventually reduced to a safe minimum. It should be noted that many competition pilots were only PR3 (Intermediate Rating) and/or were towing for the first time. For some, it was their first X-country experience. Most competitors completed at least one 100-km flight during the practice/contest days, usually along a route set for the day.

OTHER USEFUL HINTS

1. If the fenceline downwind of the pilot's take-off point is used as the "start line", it allows pilots to drift down wind with any thermal they contact, before "starting" (race tasks only). We used a system which allowed pilots to radio for a "start line". NO HEIGHT LIMIT WAS SET. (I see no functional reason for the system of a "start gate" with a set "height limit" under which the pilot must fly. Even the sailplane-glider community has given this type of start away.) If pilots did not call for a "start time" as they passed over the "start line", they had two alternatives: (a) They could return and overfly the "start line" to record a "start time". (b) Or they could continue without getting a "start time" - their "start time" would be taken as the time at which they released from tow. Pilots could register up to 3 "start times" each day, although few used more than one.

2. We used short leaders, after ensuring that pilots knew the danger of using "stretchy" bridle rope. They were 10-14 ft (3-4 metres) long. Pilots who broke weak links were requested to keep their leaders, so we had no problems if pilots got away after a thermally induced weak link break.

3. If you are running a contest, try to take a daily temperature trace by trike. The use of a temperature trace for predicting hourly thermal depth/strength, etc. is well worth the effort. The trike will also give you a good idea of any winds above, which will help task selection. Refer to C.E. Wallington's "Meterorlogy for Glider Pilots" or any similar meteorological text. Our temp. traces were usually to about 9,000/10,000 ft above the contest site.

CONCLUSIONS

As long as a suitable site is available, I can see no reason (except extreme weather conditions) which could prevent a summer, tow-launched hang gliding contest of large magnitude from being a successful and valid test of hang gliding ability.

I feel sure that, in the very near future, State and National contests in Australia will be held using tow launching. It will only need time and acceptance by other Nations, before a contest of World Championship importance, using tow launching, can be run.

P.S.

Donnell, I'll get you a copy of the article on the contest (being done by a competitor) as soon as possible, as well as some info on our trip to Alice Springs (Central Australia) for some F.A.I. record attempts. Since Nov. 1984, we have some 11 Australian and 2 World record claims in the pipeline - all from tow-launched flights.
+
Fig. 1 Suggested Layout for a 1.6 km x 1.0 km Paddock. Minimum lane spacing about 70 metres - 6 lanes. (Could have 8 lanes with about 50 metre spacing.)

N
1.6 Km
1.0 Km
6 x 1.0 Km N/S
6 x 1.5 Km NE/SW
6 x 1.5 Km NW/SE
6 x 1.6 Km E/W
*
1985/02-07

NEW MEXICO SKYTING CONTEST BEING PLANNED

Congratulations to you for another job well done in supplying use with our continued education via the Skyting newsletter. I don't want to jump the gun here, but I have some very exciting news that I want to share. I attended a city commission meeting here in Hobbs, N.M., last week, where I presented a request to use the old air base here for a skyting tournament this spring.

At this time final approval is contingent only upon my securing the necessary liability coverage, and showing and ability to control crowds and air traffic.

I have contacted USHGA about their insurance availability for such a contest. Details are not available, but I'm hoping for the best. Since I am a Lone Ranger here in Hobbs, we have not club or organization per se, but I feel confident we'll be able to work something out.

Hobbs, N.M. is noted for its excellent weather and also as a sight for sailplane activity. About 5 miles north of town is an old air base which is used by the local soaring club, the EAA, and the RC aircraft club. I am enclosing a map of the facility. Camper and trailer hookups are immediately adjacent to the air base at Mc Adams State Park. Also the beautiful Octillo Golf Course is next door. I doubt if there would be a better place in the country for a flatland skyting meet. See map.

The dates we have chosen are June 13-16. I intend to run the competition similarly to tasks required in sailplane competition. I realize of course that hang gliders are not sailplanes, so some adjustments will be made. I will have most details worked out within the next couple of weeks concerning the rules of competition. I would like to add that I see this competition as a sharing and learning function. Pilots will be responsible for their own 'rig'. In other words; bridle, release, communication devices, winch (if a winch is what you prefer to use), and tow line - if you wish to use something besides polypro rope, which is what we will be using. Tow vehicles will be supplied unless you prefer to use your own.

We certainly invite any glider manufacturers, or hardware suppliers to contact me about setting up displays or booths. If pilots wish to contact me they may do so at the following number or address. 505/392-4552 KHOB, Box 40, Hobbs, N.M. 88240.

+
One of the things that I am very interested in is glider performance while skyting. Which gliders seem to handle well on tow? Is anyone towing the Fledge? Are any manufacturers catering to the skyting pilot? Come on pilots and manufacturers, let's here some feedback. We might be on the fringe of a whole new era in hang gliding.

Merlin D. Zimmet
Hobbs, N.M.
+
CROSSROADS INTERCONTINENTAL AIRPORT
*
Next Issue:

GRANT OF EXEMPTION FOR AEROTOWING

THE PAY-OUT WINCH METHOD OF LAUNCHING HANG GLIDERS

WORLD RECORD ATTEMPTS FROM TOW LAUNCH IN AUSTRALIA
*
*

[Tad Eareckson]

1985/03
*
SKYTING NO.35
MAR 1985
*
1985/03-01

GRANT OF EXEMPTION
No. 4144
Regulatory docket No. 23980

By letter dated March 5, 1984, Mr. Steve Hawkhurst, ((Hawxhurst)) President, United States Hang Gliding Association, Inc. (USHGA), P.O. Box 66306, Los Angeles, California 90066, petitioned for an exemption from Section 91.17 of the Federal Aviation Regulations (FAR) to the extent necessary to allow an unpowered ultralight (hang glider) to be towed aloft by a powered ultralight.

Sections of the FAR affected:

Section 91.17 states, in pertinent part, that no person may operate a civil aircraft towing a glider unless the pilot in command of the towing aircraft is qualified under Section 61.69 of the FAR.

Section 103.1(b) defines, in pertinent part, the term "ultralight vehicle." For the purposes of this part, an ultralight vehicle is a vehicle that: "Is used or intended to be used for recreation or sport purposes only; . . ."

The petitioner's supportive information is as follows:

(Ed: Instead of repeating this material here, let me simply refer you to the "Petition for Exemption for Ultralight Towing" article in SKYTING No. 28.")

The FAA's analysis/summary is as follows:

On October 4, 1982, Part 103 became effective to govern the operations of ultralight vehicles in the United States. The FAA has determined that rules governing ultralight vehicles are needed to achieve an acceptable level of safety within certain airspace and to protect persons and property on the ground. The intent was to provide for safety with a minimum amount of regulation. Accordingly, ultralight vehicles are exempt from certifications and registration requirements. Similarly, pilots of ultralight vehicles are not required to an FAA pilot or medical certificate.

The FAA has chosen not to promulgate regulations regarding pilot certification, preferring that the ultralight community assume the initiative for developing and administering, under FAA guidelines, a national pilot certification program. The ultralight community is expected to take positive action to develop this and other safety programs in a timely manner and gain FAA approval for their implementation.

The FAA recognizes the value of the services rendered by the USHGA and other aviation safety organizations to the ultralight community. Furthermore, the FAA considers it to be in the public interest to promote the programs of these organizations whenever possible.

An issue raised by one commenter stated that there is a need for certification of both the pilot and ultralight vehicle. The FAA shares the commenter's concern that unrestricted operations of ultralight vehicles would not be in the interest of safety. However, the FAA strongly supports voluntary control of sporting activities. The basic premise of Part 103 is to allow ultralight vehicles to operate for sport or recreational purpose without being subjected to the regulatory requirements imposed on certificated aircraft operations. Nevertheless the USHGA has shown how it will operate under an exemption, with limitations, assuring an acceptable level of safety.

The FAA agrees that a grant of exemption allowing a powered ultralight vehicle to tow an unpowered ultralight aloft is a means to allow ultralight operators a greater flexibility in choosing a launch site and therefore afford them an ability to avoid more hazardous environments.

Operating an ultralight for the purpose of towing another is a utilitarian operation, outside the applicability of Section 103.1(b); however, the FAA has determined that an exemption is in the public interest because of the organization's ability to train students in a more controlled environment and over less hazardous terrain and because of the enhancement of safety in other hang glider operations. Experience gained from the operations proposed by the petioner will provide the FAA a basis for determining whether rulemaking with appropriate limitations should be considered.

In consideration of the foregoing, I find that a grand of exemption is in the public interest and will not adversely affect safety. Therefore, pursuant to the authority contained in Sections 313(a) and 601(c) of the Federal Aviation Act of 1958, delegated to me by the Administrator (14 CFR 11.53), the individuals authorized by the United States Hang Gliding Association, Inc., are granted an exemption from the Federal Aviation Regulations to the extent necessary to allow unpowered ultralight vehicles to be towed aloft by powered ultralights. The exemption is subject to the following limitations:

1. Each operation must comply with all sections of Part 103, except Section 103.1(b) of the FAR.

2. No charge, assessment, or fee may be made for the operation of the towing ultralight except the actual expense of the specific flight.

3. Both occupants on both ultralights must posess a current pilot rating issued by the United States Hang Gliding Association.

4. For identification purposes, the United States Hang Gliding Association, Inc., shall issue an individual authorization to each person allowed to conduct operations under this exemption. Each authorization shall include an identification number and a copy of this exemption. The United States Hang Gliding Association shall have a procedure to rescind this authority when needed.

5. Operations conducted under this exemption shall be in accordance with the safety and certification rules and guidelines, as amended, established by the United States Hang Gliding Association, Inc., including those specified in paragraphs 1 through 12 in the petitioner's supportive information. (SKYTING #28.)

6. Each individual who operates an ultralight vehicle under the authority of this exemption must be familiar with the provisions contained herein and must have in his or her personal possession a copy of the authorization issued by the United States Hang Gliding Association, Inc., and a copy of this exemption. These documents shall be presented for inspection upon request by the FAA.

This exemption terminates on June 30, 1986, unless sooner superseded or rescinded.

Kennet S. Hunt
Director of Flight Operations
Issued in Washington, D.C.
on October 25, 1984

((Kenneth))
*
1985/03-02

THE PAY-OUT WINCH METHOD OF LAUNCHING HANG GLIDERS
-some theoretical considerations

by Edmund Potter
Bruwell, Cambridge
ENGLAND

PART 2. TOWED FLIGHT

3. STEADY TOWED FLIGHT

The exact equations for towed flight are derived in Appendix D. The towline tension (T) and inclination to the horizontal (Gamma) are the additional factors. The angle Beta now represents the angle of climb when positive.

Table 2 shows a typical set of values. The best angle of climb for a given tension and inclination is achieved when CL/CD is a maximum - the same condition as for the best glide in free flight.

Using the related values of Alpha, CL and CD found earlier (SKYTING #34, Table 1) the climb angle, rate of climb, attitude and true airspeed can be calculated for various combinations of T and Gamma.

A word of caution is needed here if the CL and CD values are to be used at flying speeds other than those obtained in free flight at normal weight. The hang glider is a flexible aircraft with will distort under load, so that CL and CD may vary with load for a given Alpha.

In practice there is little to be gained by flying at high speed on the tow, so this possible change in flying characteristics (almost certainly a degradation of the performance) has been ignored.

It is not possible to fix the position of the pilot. The line of action of the tension force as well as its inclination would be needed for this. Moreover, the range of attitudes and flying speeds may be significantly curtailed in practice by the method of attachment of the towline to the hang glider.

Apart from this consideration the exact method of connecting the towline to the hang glider is not relevant to these calculations. The resultant force on the hang glider must always be along the towline at the point of attachment.

3.1 The effect of towline inclination

Table 3 shows the result of increasing the towline angle through successive steps of 10 degrees, at a constant tension of 100 lb and at the optimum angle of incidence.

The climb angle falls off very significantly as the towline becomes more vertical. At 70 degrees the hang glider is barely climbing at all, even at 100 lb tension.

In practice it is found there is little to be gained by flying with a towline angle of more than 40 degrees to the horizontal.

As the vertical component of towline tension becomes greater at higher inclinations, the hang glider has to fly faster (at the assumed constant angle of incidence) in order to provide a greater lifting force.

Fig. 5 illustrates the attitude, climb angle and speed for different towline inclinations from zero (take-off) to an extreme 80 degrees as calculated in Table 3.

3.2 The effect of towline tension at different inclinations

Tables 4-6 show the effect of tension at take-off (Gamma=0); at a moderate value (40); and at an extreme value (70).

Take-off (Table 4)

Common sense considerations dictate that a nose up attitude of more than 40-45 degrees near the ground could be dangerous in the event of a towline break. It would probably be better therefore to limit the tension on take-off to 75-100 lb maximum, which will still give a very good angle of climb.

Immediately after take-off the hang glider is likely to encounter faster moving air in the first 50 feet of climb. It is difficult to calculate the effect of this except to say that in practice the pilot often feels the need to "pull in" to avoid the nose rising too sharply.

Somewhat slower take-off speeds can be realised at higher angles of incidence but with higher nose-up attitudes. It is felt better however to take off with a margin of speed to cope with gusts etc.

40 degree towline inclination (Table 5)

This represents a fairly typical angle during the tow launch. As soon as a safe altitude of a few hundred feet has been reached the towline tension could be increased to 150-200 lb without unduly loading the hang glider or incurring nose-up attitudes.

70 degree inclination (Table 6)

There is nothing to recommend flying at this inclination, but it is included because the situation may be encountered in practice when "tacking" from one crosswind runway to another.

4. THE TOW LAUNCH

Contrary to sailplane practice, the pay-out winch starts close to the hang glider at the downwind end of the runway. The initial separation distance is usually a few hundred feet between the winch and the hang glider.

As the winch accelerates up to crusing speed, the hang glider lifts off, and the towline pays out from the cable drum on the winch. The maximum breaking torque that can be applied to the drum is preset, thereby limiting the maximum tension that can be applied to the towline.

The launch ends when the winch vehicle reaches the upwind end of the runway, since there is nothing to be gained from retaining the towline after it has gone slack. The winch drum is not capable of winding in the towline except of course after the towline has been released by the hang glider.
+
APPENDIX D.(1)
EXACT EQUATIONS FOR TOWED FLIGHT
VERTICAL
HORIZONTAL
AIRFOIL DATUM
CLIMB PATH
a
B
Y
L
D
W
T
Definitions:
a = Angle of attack (incidence)
B = Angle of climb
Y = towline angle
T = Towline tension
L = lift
D = drag
W = weight
p = air density
V = true airspeed
S = kite wing area
For steady non-accelerated flight the forces must be in equilibrium, and will pass through a point (not necessarily the centre of mass of the kite, though).
The resultant of lift and drag must be equal and opposite to the resultant of tension and weight
A somewhat more convenient form of (1) for calculation if B is evaluated first is given by substituting for L + D in (2), i.e.
+
TOWED FLIGHT
+
TABLE 2
+
TABLE 3
+
TABLE 4
+
TABLE 5
+
TABLE 6
+
Figure 5. ATTITUDES ON TOW (See Table 3)

T = 100 lbf
Y = 0 degrees
Y = 20 degrees
Y = 40 degrees
Y = 60 degrees
Y = 80 degrees
*
1985/03-03

WORLD RECORD ATTEMPTS
- Alice Springs -
Nov./Dec. 1984

by Denis Cummings
Singleton, AUSTRALIA

Alice Springs, in the deserts of Central Australia, has been the site used by glider pilots to set about half of the current F.A.I. gliding World Records. With tow launching now opening up this area to hang gliders, it was only a matter of time before World Hang Gliding records would be attempted at "The Alice".

The site chosen was Bond Springs Airstrip (local glider club strip), ground level about 2380 ft ASL, about 20 km north of Alice Springs. It's not far below the Tropic of Capricorn, and has a January AVERAGE daily maximum temperature of 37 C (99 F) and humidity of 18%. The glider pilots tell of riding the shear waves (due to Westerly upper winds blowing over the lower (?) Easterly convection layer) that START between 15,000 ft and 20,000 ft.!!!

Graham Puckallus and some of his Brisbane (Qld.) mates did the organising, and we ended up with 10 pilots and 4 drivers. Some flew out (not by h-g; they used jets) while a couple of us drove - 40 hours over some of the dustiest and roughest roads I've ever travelled. The sights of those wild and remote parts of Australia were well worth the discomfort.

We had some success. At least 2 Delta Silver Awards are being claimed as well as the following records: -

GEN. CATEGORY - WEIGHT SHIFT ONLY

WORLD & AUSTRALIAN

Distance around a triangular course - 18.2 km (new record)

AUSTRALIAN

Open Distance - 172 km (Previous - 157 km)

Gain of Height -
(1) about 9000 ft
(Previous - 7700 ft)
(2) about 10,500 ft
(1 day after (1) )
(3) about 12,800 ft
(1 day after (2) )
(World record is 13,700 ft)

GEN. CATEGORY - CONTROL SURFACE

AUSTRALIAN

Gain of Height - about 9000 ft
(new record)
(World Record is 9250 ft)

It is interesting to report that the winds were generally very light - normal in that area. Thermals either went to an inversion layer or cloudbase (at between 14,000 ft and 16,000 ft ASL on good days. the final glide on the best "distance" day lasted over 1 hour and covered about 50 km. Thermal strengths were regularly "off scale", but an "average" showed about 1300 ft/min on quite a few occasions.

We were limited in many ways. DOA (the aviation regulators) only allowed us the use of an area between the roads running North and West from Bond Springs. This meant that flight was only allowed in the North to West quadrant. It was about 100 km from Bond Springs before any road branches were reached, so we were effectively limited to following the North Road or the West Road. The area between the roads was uninhabited, untracked low scrub. Height limits started at 10,000 ft ASL (7500 ft AGL) within 50 km of the strip, and rose to "unlimited" 50 km West and 15,000 ASL (13,000 ft AGL) 50 km North. After a few days, the height "consessions" were taken away, and we were limited to 10,000 ft ASL. The local DOA staff were made aware of our displeasure. In Australia, because of ancient aviation thinking and laws, it is possible to be in one of the most remote parts of the country and still be severely limited (legally). Don't even try to fly in the Ayers Rock area - it is not part of Astralia, except for a few Aborigines and the tourist-hungry charter pilots.

A TV filming session at "Their Rock," which had been planned some six months previously, with DOA's knowledge, had to be cancelled when DOA withdrew our "concession" to fly in the area at the last minute, due to pressure by the local charter pilots. Some "free" country we have here!!!

One of the interesting things discovered at Bond Springs was the use of willy-willies (dust devils) for getting up after launch. At first, we tried to stay on the ground if any willy-willies were seen near the strip. Slowly, as we had chance encounters with some that sprang up as we were launching, we started to look for them before we would launch. Happiness is a 200 meter diameter willy-willy below you in the center of the strip!!!

Our host, the glider pilots of Alice Springs Glider Club, were wonderful. They let us take over their club-house & their barograms, and shared both their strip and their thermals. The best contest was between the NT glider champion and a local hang glider pilot (intermediate rating and his 3rd of 4th thermal flight). They joined in a thermal over the clubhouse at about 600 ft AGL and topped out about 9000 ft later. Both were being encouraged by their grounded mates.

"Don't let him get above you" - by the g-g crew.

"C'mon, catch up to him" - glider pilots. At the end, the glider boys claimed "a tie", but we knew better. I think we won a few converts to hang gliding during our stay.

The local weather boys at DOA were a lot more helpful than their bosses. A weather balloon was launched at about 9:00 a.m., and we were able to get the temp. and dew point traces, as well as synoptic info., etc. at between 9:30 and 10:00 a.m. This helped us to pick launch time and to set our tasks each day.

About the flying. Most days, thermals "averaged" 1000 ft/min or more at some time during the flight. About 6 out of 10 days were "good" days, it was either heavily overcast (1 day) or low inversion (5-6,000 ft) - 3 days. The only pilot with us who had flown in the Owens Valley came down to land after 100 km as he was sick. On a good day, you could stay high (and bloody cold). On others, you would be regularly getting ready to land before you picked up your next thermal. On the two occasions that I completed a set course it was heartbreaking trying to find some sink so that I could get down to land at my goal. Overall, the flying conditions were some of the most taxing and most enjoyable I've ever experienced. The sight of the McDonald Ranges and the Red Centre from 15,000 ft is hard to describe.

A lot of thanks must go to our drivers, who were ALWAYS below us on the road. Without them, it would have been impossible to fly at all in the area.

After being at "the Alice", I'm not sure that I would be prepared to go to the time and expense of traveling there regularly to attempt record flights. Without a doubt, it would be one of the best potential record setting sites in the world. The number of "good" and "excellent" soaring days between November and April must be the highest in Australia. However, the remoteness, together with the current attitude of the DOA, tends to dampen my enthusiasm to return. Also, I feel that we have areas in the Northwest of M.S.W. which approach the same record-setting potential, without having those drawbacks.

Then again, if any of you are planning a trip out there next summer, please let me know. I just might - - - -
*
1985/03-04

ENJOYED MON'S ARTICLE

Dear Donnell,

I appreciated "A Regional Competition From a Wuffo's Point of View," by Mary (Mom) Hewett (SKYTING No. 32). It brought to mind the Legend of Wuffo, the text of which is enclosed.

Mention was made in the article that "Hang gliders make excellent umbrellas.) Which recalls the idea that circular wings have excellent stability and if built as gliders might be good for tethered flight or sled rides; umbrella type design would make for record setup times. (Ed. Seems to me like I tried that as a kid. And without much success.)

Mary (Mom) Hewett has reached the biblical three score yours and ten (Psalms 90:10). As the article mentions "70 years old and fragile"; and as all pilots young or old are as essentially fragile while flying, fragile, handle with care, safety packaging is needed. Pilot protective pods or other safety packaging should be used with all gliders.

Hope that 1985 has more emphasis on safety; more R and D on safety equipment is needed.

Edwin G. Sward
*
1985/03-05

THE LEGEND OF "WUFFO"
Or
How "Wuffo" Came To Be!

As narrated to Editor Donnell Hewett by Edwin G. Sward

Long ago in the soaring seventies, way back in the dim mist of the early beginning of the present era of foot launch gliding, some pilots went'a kiting.

It was on this kiting excursion, that a free roaming dog bit a pilot on the leg, causing perhaps a less than graceful launching or landing. And it was the occasion for much humor amonst his fellow pilots.

The humorous banter went somewhat like this, - "So the dog, bit you?" - "Yeah! the D.O.G. bit me." - "Where'd he bite you?" - "On the leg." - "What did he say his name was?" - "He didn't give me his name." - "You mean the dog bit you and you didn't say anything?" - "Well, he said, 'Woof!'" - "Then Woof must be his first name. But Woof who?" - "What do you mean Woof who? He didn't give his last name."

This became an "in" joke amongst that group of pilots and whenever an unfamiliar dog or person, etc. wandered into the area, or a snafu occurred, they'd say, "Woof who? Woof who?"

Whenever they flew, other pilots knew that, "Woof who? Woof who?" was a very "in" joke amongst that group of pilots and not really catching the meaning of the pronunciation of "Woof who? Woof who?" nor wanting to appear as being "wuffo's" themselves, they took up the cry of "Wuffo! Wuffo!"

And that's how "wuffo" came to be.

(Ed. Gee, and all this time I thought "wuffo's" were so named because of the characteristic sound they always make when they open their sweet little mouths: "Wuffo you goin' hand gliding?" - "Wuffo you putin' that funny apron on?" - "Wuffo you hookin' that there?" - "Wuffo a hand glider has that pole on top?" - "Wuffo you trying to kill yourself jumpin' off that cliff?" - etc. - etc. - etc.)
*
1985/03-06

EXPERIENCES AND IDEAS FROM NEVADA

Dear Donnell,

We've been towing for several months now on the dry lakes that are plentiful in this area. We've had good success although no cross country flights, but I'm sure that will change in the warmer months ahead.

RELEASE MALFUNCTION

I use a single point release (mini-owens) which works very well. It did, however, fail to release once and I had to pull the bridle apex up to where I could release it by hand. So now I use graphite on the release if it all seems "sticky" from being dragged through the dirt.

INCIDENT

I did have one unpleasant incident. Right after a perfect take-off one wing started to come up. I high-sided it but to no avail as the wing continued to rise. At this point I felt as if I might be slipping into the ground. I had had adverse yaw problems before, but nothing like this.

Right as the glider finally started to come around and roll back the way I wanted it to, the weak link broke. At this point the force of the yaw was already too great and the turn continued so that I was now flying downwind maybe only 30 ft above the ground. Well, I managed to get the glider back into the wind (sort of) and landed without any damage. It seems to me that after this incident that there are those situations where a thermal or cross-wind, coupled with the adverse yaw phenomenon, can overpower the pilot's roll authority - at least momentarily - which could have bad consequences if one is close to the ground.

If this situations happens again, and my altitude is less than 100 ft, I intend to release before the wing has come up so high, instead of just thinking that the glider has got to level out.

So until someone comes up with a solution to the adverse yaw, I won't be totally confident. Maybe it's just something we'll have to put up with and be prepared for.

CROSSBAR TOWING

I've considered towing from the crossbar as you suggested, as my 184 Gemini seems to exhibit the adverse yaw problem at least as much as any glider we've towed. But first I think I'll suspend 66.6 lbs (1/3 of the 200 lb. test weak link) from the crossbar to see how the pivot tang reacts to this load. (Ed. Personally I've found that the floating action of my Gemini's crossbar works well with over 100 lbs pulling down on it. Therefore, I tow my Gemini from the crossbar and find the adverse yaw effect essentially eliminated. However, I cannot recommend this practice to others because the system was not DESIGNED for such a load on the crossbar. Needless to say, I inspect the system carefully for wear and operation before each day's flying lest something break and leave me trying to fly with a folded-up glider.)

PRESSURE GAUGE PROBLEM

We use the "Midwest" hydrolic pressure gauge which works extremely well. We've only had one problem with it. Where the plastic oil line attaches to a metal fitting, the line kinked and then broke. The problem was solved by treading the line through a small spring and pushing one end of the spring over the fitting.

WALKIE-TALKIES

We use walkie-talkies for communication. My own personal set-up utilizes a power mike clipped on the base tube. I bungie the switch down, and the mike is so sensitive that the tow vehicle can here me give instructions even when I'm standing up. Once in the air I immediately go prone and flick the bungee off the switch thus establishing 2 way communication. The mike is situated on the base tube where I normally hold my thumb on the switch to talk - without lifting my hand from the base tube.

SHOULDER PADS

As long as I'm on the subject of ideas, here's one. Why doesn't some manufacturer make a harness with extra wide, padded shoulder straps. This addition could prevent broken collarbones expecially with the new unbreakable faired downtubes. Probably even better would be to incorporate hard plastic shoulder pads (such as football players use) into the design of shoulder straps. Just a thought.

I really enjoy and appreciate your newsletter.

Mark Tracy
Las Vegas, NV
*
1985/03-07

PROGRESS IN ENGLAND

by Tony and Rona Webb
41 Kinsdale Drive
Thurnby Lodge
Leicester, U.K. LES 2PS

Much has happened since last we spoke.

NEW COMPANY

At last our Company is in existance. It has taken over 8 months to formulate, we have only just begun to trade, and it will be sometime before a profit is seen. We are entering the lengthy business of aquiring a site to build the towing center. While we fully understand that skyting can go on in a multitude of different places, here in England congestion is the name of the game.

In order that pilots can reach an efficiency upon the line to deal with the problems of hedges, crosswinds, buildings, power wires, cows and sheep, crops, and land owners, it is necessary to do early towing in ideal conditions. Also for the purpose of holding meets, competitions, and development work, 3 or 4 disused airfields would be an advantage. The British Gliding Clubs have quite a number around the Country.

B.H.G.A. TOWING COMMITTEE

A new development within our British Hang Gliding Association: we now have a towing subcommittee. A colleage called Mike Mavin and myself have been "coopted" for this purpose. I have been made the official developer of the system, working under the control of the chairman Mike. This means that we now have insurance cover for our towing activities - 3rd party - which is awarded to all foot launchers.

Our small conversion course for experienced Hang Glider pilots to towing is accepted as sound and effective. We are prepared to visit clubs around the country in the next year to train pilots in towing practices. So far such activities have been received well. The most difficult is to convince pilots that paying for experience financially is far better than medically - both in terms of personal safety and in terms of good practice. On thing this sport does not need is a repetition of high accident rates.

We agree with your Skyting 33 letter concerning the ignorant attitude towards laws and guidelines, and that tuition is far more effective in the long run. However tuition, I feel should be accompanied with a set of guidelines and existing laws. We have put together a set of such rules which are currently under discussion. As with any committee, the speed of movement is slow. However, there is a strong feeling that towing will be on the increase this year.

The Chairman of the B.H.G.A. puts a lot of faith in towing as a way to stimulate the increase in pilots in the UK. The weakest link in Hang Gliding is training. Our inclement weather restricts the training pilot so much that few actually succeed in flying.

The towing committee has been asked to sensibly construct safe ab initio teaching in liason with the present training committee.

DREAM COMING TRUE

This letter seems to say committee, committee, committee. Well, I must confess that when we left Texas muttering things like teaching and flying schools, it was a dream. Now that dream is close to a reality. I guess that as long as you trust in your God and never quit you can't go wrong.

OVERFLYING WINCH

I will raise one more point of conjecture now that towing moves to the realms of competition. (It is envisioned that 2 or 3 towing meets will be held in the UK this year.)

What do you think about the potential problems of overflying the winch or vehicle? This situation has not presented itself with us due in the main, I suppose, to cautious procedures. The situation of tight line and glider approaching near vertical situation is met immediately with tension release or line cut. The weak link would indeed fail when the energy in the wing increased if the line tension were not released. This question is asked in the light of our system not having an automatic overfly release. In order to produce the auto-release, I feel the mechanism should be at the surface end and not the bridle, to avoid complications. What are your thoughts on this subject?
*
1985/03-08

ANSWER (By Donnell Hewett)

It was good to hear about your finally getting your business off the ground and that attitudes are beginning to change toward towing in your area.

Now concerning my opinion of the problem of overlying the winch or vehicle. I do see you it could be very dangerous. However, the situation is so OBVIOUSLY dangerous that I believe it will remain forever a minor problem statistically. Any pilot who finds himself overflying the tow will almost certainly recognize the situation long before it happens (unless he is a beginner on a short rope, in which case he should NEVER be flying at that tow angle). I am sure that any pilot who finds himself overflying the tow will do everything in his power to release. If he cannot release, then there is a more serious problem than overflying - namely flying with an unreliable release system.

If the ground crew sees a pilot overflying the tow, they should release him from the ground as soon as possible. This probably means free-wheeling the winch or reel, disconnecting the line from the vehicle, and/or cutting the rope. Again, I see no major problem here. If the pilot is on a long line (as he should be before allowing himself to overfly the tow) there should be several seconds in which the ground crew can respond before the situation becomes critical.

One last comment: Obviously the power winch operator should be aware of the danger of overflying and cut the power before overflying occurs. After all, he will be pulling the glider straight down when overflying does occur and should cut power well before that.
*
GUATEMALA WANTS SKYTING INFORMATION AND EQUIPMENT
*
1985/03-09

Dear Donnell,

I have been reading about towing activity. I practice hang gliding since 1977 and teaching since 79. In this country there are good mountains, volcanos, and excellent flying conditions.

Now we are considering towing. We believe that it has a lot of potential fun and the possibility to fly new places. I got from a friend from Honduras the magazine Skyting #1. It looks like the best developed system actually.

We would like to buy the complete system you have developed: - bridle, belt, keel ring, leader, weak link, towline (3000 ft). Please indicate to us which is the best tension gauge and how to adapt it to the car or boat and kind of floaters for the glider.

Alejandro Diez Pinto, Presidente
Asociacion de Vuelo Libra
Guatemala City, C.A.
*
1985/03-10

Dear Alejandro,

If you are seriously considering towing, I would strongly recommend that you get ALL of the back issues of the SKYTING Newsletter. This is expensive (US$50.00 for the issues through No. 35), but until a book can be written on the skyting towing technique, it is the ONLY way to become familiar with the problems and solutions associated with this form of towing hang gliders. (Skyting No. 1 describes the original system. The other issues describe what can go wrong with this system and how to improve it to make it safer.)

These issues also tell where you can obtain the equipment needed to skyte safely as well as how much it costs, and in many cases how you can construct your own equipment from what you can get locally. I am not really in the retail business for the purpose of selling towing components or complete systems. However, as a service to the hang gliding community - particularly to those pilots living in remote areas - I will ship them those components I can get which they cannot find more conveniently and less expensively elsewhere.

Bridle - I can ship you an apex release (single-point, 3-ring, pull-string release) bridle for US$50.00, or you can probably make your own for about half that price.

Belt - Many pilots simply tie a rope, or clip a strip of webbing to their harness (at the bottom of the main hang straps) and pull from there. I have sewed a ring to my harness right below my parachute.

Keel ring - I can send you a clamp-on keel ring for US$5.00, or you can tie your own ring to the keel for about $0.50.

Leader - If you use a NON-STRETCH bridle (strongly recommended) you can use a short leader or none at all. I no longer use a leader, but some pilots still use a 15 ft (5 meter) made of 3/8 inch polypro rope. I imagine you can get this locally. If not, let me know. It's not very expensive.

Weak link - A roll of weak link line that breaks at about 200 lbs can be shipped to you for US$5.00. I suspect you can get the same No. 18 nylon twine locally for considerably less. (Try your fishing supply stores.)

Towline - I can send you 3000 ft of towline for US$170.00, but you can probably get it locally for less. In the first place, you probably do not need that much. Most pilots tow with about 1000 to 2000 ft of line. Too long a towline can produce too much stretch. Just about anything will work - from nylon, to polypro, to steel cable. Most pilots go with the cheapest thing they can get locally. I suggest you start with about 1000 ft and lengthen it as needed.

Tension gauge - I use a hydraulic tension gauge. (I could make you up one for US$170.00) However, there are other alternatives which are probably just as good and cheaper as described in back issues of SKYTING. The one I would like to try is the electronic gauge, but I have not had an opportunity to do so.

In addition to the above, it is now recommended that anyone towing with 1000 ft or more of towline should have radio communication between pilot and driver. If you do not already use radios, you may want to consider this as part of your towing system.

Let me know if I can be of further service.

Donnell
*
Next Issue:

THE PAY-OUT WINCH METHOD OF LAUNCHING HANG GLIDERS
PART 3.

1984 ACCIDENT REVIEW
by Doug Hildreth and Donnell Hewett

THE SKYTING CHALLENGE
by Doug Gordon
Suggestions for improving the safety of skyting, particularly in regards to skyting instruction.
*
*

[Tad Eareckson]

1985/04
*
SKYTING NO.36
APR 1985
*
1985/04-01

THE PAY-OUT WINCH METHOD OF LAUNCHING HANG GLIDERS
-some theoretical considerations

by Edmund Potter
Bruwell, Cambridge
ENGLAND

PART 3. Changing the Variables

4.1 Calculation of the height obtained during a tow launch

This is a relatively simple exercise. The initial starting position o the winch on the runway is chosen (Appendix E). Values for towline tension, winch speed and headwind etc are selected, and the approximate desired airspeed is determined by chosing a convenient value of Alpha and corresponding values of CL and CD from Table 1.

The programme works in 200 ft steps along the runway. At each step, the new height of the hang glider is found, and hence the new towline inclination and angle of inclination and angle of climb. These are assumed to remain constant throughout each step.

The printout (Appendis E.) shows each 200 ft step and lists various of the parameters involved. The analysis involved in section 5 below uses the 5200 foot line which corresponds roughly to 1 mile of runway.

Assumptions

The tension is assumed constant throughout the launch. This is clearly not ture in practice for the winches presently in use, since the effective drum diameter is decreased as the line is payed out. The towline tension will actually increase towards the end of the launch, thus improving the climb angle attained.

An opposing effect is created by the weight and drag of the towline which in reality does not conform to the assumed straight line between winch and hang glider. This effect increases the inclination of the towline at the hang glider and decreases the height obtainable.

For simplicity and convenience these two effects have been ignored. Conceivably they could be calculated, but the validity of the comparison between runs in unlikely to be significantly improved.

5. FACTORS AFFECTING THE HEIGHT GAINED

See tables 7-11.

In each case the factors that are being investigated are listed in the first two columns, and the altitude attained (YK) is shown in the third column. The greater the altitude the better the launch - within reason.

5.1 The initial separation of winch from hang glider - Table 7

Starting close to the hang glider gives poorer results. At first sight this may seem unexpected, but the reason is found in the larger towline angles in the early stages of the tow.

Beyond about 600 ft there is no advantage because the runway is being unnecessarily used up by the winch.

In practice a distance of about 400 ft allows easy communication between pilot and winch, and is a reasonable compromise.

5.2 Effect of a headwind - Table 8

The winch speed is reduced commensurately to allow a fair comparison.

A headwind is a significant advantage. It is worth about 300 ft extra altitude for 10 mph. In effect it lengthens the runway. Flying in winds of 20 mph or more is not recommended for the practical reason of being unable to penetrate upwind.

5.3 The effect of towline tension - Table 9

The winch speed has to be increased to compensate for the increased load on the hang glider and its consequent higher airspeed.

Increased tension gives greater altitude - very roughly 60 ft for every extra 10 lb tension. The required winch speeds (if there is no headwind) may well become impracticable at tensions beyond 150 lb.

5.4 The effect of winch speed - Table 10

The optimum speed of the winch is that which keeps the towline angle below about 40 degrees. Faster than this the runway is used up too quickly. Slower than this the towline angle becomes too steep. This applies whether or not there is a headwind.

The winch speed must of course be such that the towline is always paying out, otherwise the towline tension will not be maximised.

5.5 The effect of angle of incidence - Table 11

Pilots are not usually accustomed to thinking in terms of this, and without an angle of incidence indicator they cannot tell what it is except indirectly from their sensation of airspeed and altitude.

It is important to realise also that the pilot's body position in towed flight may not be anywhere near the position he or she is used to for a given airspeed in free flight. However the pilot's instinct to push out to decrease airspeed (and increase the angle of incidence) or to pull in and increase airspeed (and decrease the angle of incidence) does not hold good.

The theory shows that the optimum angle of incidence is that which gives the flattest glide in free flight. For the hang glider in question this gives a speed range of about 5 mph over which the climb angle is the best attainable. The airspeed at which this occurs on tow is dependent on the loading on the hang glider.

5.6 The effect of crosswind - Figure 6

A crosswind can be resolved into two vector components: a headwind, and a sidewind at right angles to the runway. The headwind component can be expected to provide the advantages mentioned in 5.2 above. The sidewind component has no effect in this respect.

There are two practical responses to the sidewind. One is to fly directly above the runway by "crabbing"; the other is to fly to the leeward side of the runway. Both techniques are manageable but give somewhat different results.

Flying crabwise meats that a component of the towline tension is pulling the hang glider sideways. This has to be offset by opposite weight shift. Also the forward component of tension is reduced and the climb angle suffers.

Flying to the leeward means that the hang glider is pointing along the towline direction and so no tension is thereby lost. In addition the towline is being pulled off the drum at an angle to the drum axis and consequently an increased towline tension is experienced, improving (increasing) the climb angle.

Given a choice, the leeward option is preferable.

5.7 The effect of lift and sink

Typically the time spent on the tow is about 2 minutes. If moderate lift or sink is encountered (say about 200 ft/min) this could amount to plus or minus 400 ft on the altitude reached.

The recommendations in these cases are the same as for free flight. Speed up in sink to minimise the time spent in it. Slow down in lift to maximise the time spent in it.

In practice whilst mild sink is often widewpread, lift tends to be more localised and there is often more to be gained by releasing early into a patch of lift than by hanging on until the end of the towlaunch.

6. CONCLUSION

The intention of this report is not so much to lay down limits or rules but to help people understand the principles of tow launching. It is by the intelligent application of the principles together with a cautious exploration of new techniques that this developing field of hang gliding will best be served.
+
APPENDIX E. (1) COMPUTER PROGRAM FOR THE TOW LAUNCH
+
TOW LAUNCH SCENARIO
ONE STEP
0 = INIT. POSITIONS
1 = POSITIONS AT END OF STEP
+
APPENDIX E. (2) TYPICAL PRINTOUT FROM COMPUTER PROGRAM
+
TABLE 7
EFFECT OF INITIAL SEPARATION
+
TABLE 8
EFFECT OF HEADWIND
+
TABLE 9
EFFECT OF TENSION
+
TABLE 10
EFFECT OF WINCH SPEED
+
TABLE 11
EFFECT OF ANGLE OF INCIDENCE
+
NOTES ON TABLES 7 - 11
The following factors are held constant unless specifically stated otherwise.
Runway length: 5200 ft
Winch speed (VW): 30 mph
Headwind (VA): 0 mph
Towline tension (T): 100 lbf
Angle of incidence (Alpha): 16 degrees
Initial separation of winch from hang glider: 400 ft
Other terms used:
XK: horizontal distance covered by hang glider (ft)
YK: altitude of hang glider (ft)
TL: towline length (ft)
VK: true airspeed of hang glider (mph)
Beta: angle of climb (degrees)
Gamma: towline inclination to the horizontal (degrees)
*
1985/04-02

MORE ON CIRCULAR WINGS

by Edwin G. Sward
Worcester, Mass.

The awarding to you of the Ed Guardia Trophy is indeed an indication of the significant contribution to the sport by you, and it is well merited. Congradulations.

Skyting I think is in a sense where foot launch gliding was in 1975 and by 1995 I would think that skyting launches will be more often the method of launch rather than hill or mountainside launches; and your effective leadership in promoting the safe development of towing is mentioned also.

Safety Chairman, Doug Hildreth, is an early advocate in the need for pilot protective farings.

As a youth the parachuting performance of umbrellas was a disappointment to be also.

A good idea source book is:

Incredible Flying Machines
by Michael F. Jerram

Exeter Books
Marshall Cavendish
New York
London and Sydney
First Printing 1980

P.68-69 of said book has useful references about circular wing's "desirable properties".

Possibly circular wing gliders could be designed to have full or partial umbrella type set up capabilities.

Best wishes for your contributing skyting R&D success.
*
1985/04-03

84 ACCIDENT REVIEW: 4+4 for 84

by Doug Hildreth

The numbers are good for this year, only four foot-launch and four towing fatalities. We are all very pleased about that. But do not be misled or become smug -- it could have been worse. There were a number of pilots who were severely injured, were in critical condition for several days and then finally pulled through.

Although there is a tendency to focus on the number of fatalities and on the specific causes of those fatalities, I encourage you to look carefully at the causes of all accidents.

Hang gliding is in a maturing phase but the experienced, complacent pilot is still making the same mistakes as he did a few years back.

HOOK IN

There were 12 - that's TWELVE - foot launch failures to hook in! Miraculously there were no fatalities in this catagory. Last year I wondered if the 8 failures to hook-in were just a result of better reporting, but now there is no doubt in my mind that the increase is real -- very scarey. Having practiced climbing into the control bar during parachute clinics saved a couple of pilots.

This is one thing we can really do something about: hook in/hang-check, hook in/step-through, hook in/lift-glider. Don't allow distractions. Repeat the entire sequence if you unhook for any reason.

(Ed: Note that there was one out of four towing fatalities this year which resulted from failure to hook in. In the case of tow launching, the rule is: ALWAYS HOOK-IN BEFORE YOU HOOK-ON. In other words, make it a habit never to HOOK-ON to the towline before you HOOK-IN to the glider.)

LAUNCHING AND LANDING

The majority of accidents continue to occur at launch and landing. A few years back, launch problems were the most common. Instructors and clubs put on a big push to prevent stalls/crashes on launch - and I'll be darned, they were successful. Crashes on launch decreased. New they are back up where they were before. But don't despair - learn from it. We can figure out where our problems are. We can mount a nationwide campaign to solve a problem. We can be/were successful! But we cannot rest on our laurals - or it will rise up again like the Phoenix of old. I frankly believe that the same thing occured with hook-in, but less dramatically because the original numbers were smaller.

MISCELLANEOUS

We continue to fly into almost anything that is available - trees, bushes, fences gliders, vehicles, and power lines.

Strong weather remains a factor of approximately the same magnitude as previous years.

There were 3 incomplete assemblies. Two involved pins securing the control bar to the keel bracket which were probably not inserted during assembly (rather than coming out in flight). In both, the control bars "disconnected" as the pilots went to the uprights on landing approach. In all three instances the pilots were seriously injured and recovered.

Two pilots missed their leg straps when putting on their harnesses.

There were several problems at launch involving poor communication between the pilot and the wireman. It is critical that this communication be clearly understood by both, especially if the wireman is not a pilot.

DIVES, TUMBLES, SLIPS AND INVERSIONS

There were 17 instances when gliders assumed attitudes not planned for or approved of by their pilots. Most of these were tuck-tumbles with a few dives, rolls and slips. Eight were aerobatic induced and nine were weather induced.

PARACHUTES

Eighty-nine percent of the pilots wear parachutes (the majority who do not wear parachutes are those who are new to the sport). Sixty-three percent of them repacked their chutes in 1984. There were reports of 16 successful deployment with survival of the pilot and there was one accidental deployment without injury.

TOWING

There were four towing fatalities. All of these were directly related to the towing process. Last year all three towing fatalities I considered "fringe activities" but this year the fatalities seemed "legitimate" -- occurring during or after formal instruction. The exception was the experienced pilot who hooked-in to the towline rather than the hang loop. All of these occured during land towing incidents. I received no reports of air-to-air towing incidents. I am certain that there has been a significant increase in towing activities in the last year, so whether the incidence of towing accidents is up or down, I cannot say, but the absolute numbers of fatalities speaks for itself.

Towing is here to stay. We know it can be done safely and there is much information available on correct towing practices. The USHGA must continue to develop and disseminate these programs.

SUMMARY

In summary, the sport is maturing and in 1984 there were fewer deaths -- only four foot-launched/free-flying and four towing.

We are making the same old mistakes, particularly with launching and landing. The increases in failures to hook in is distressing.

IT'S BACK TO BASICS FOR ALL OF US.

RECOMMENDATIONS

Things you can do towards a safer 1985:

Check to see everyone you know has hooked in; don't forget yourself.

Review and actively practice correct launch techniques (run hard).

Plan and execute your landing approach with an extra margin for safety.

Learn defensive crash posturing.

Minimize your exposure to strong weather conditions.

Be conservative with new gliders and new sites.

Reread Russ Locke's article on landing in the surf (HG August 1984).

Repack your parachute this Spring.

HANG GLIDING FATALITIES

Year
Foot Launch
Towing

1971 02 -
1972 04 -
1973 09 -
1974 40 -
1975 32 -
1976 38 -
1977 24 -
1978 23 -
1979 30 -
1980 22 1
1981 16 5
1982 11 1
1983 11 3
1984 04 4

TOTAL
ACCIDENT CAUSES

84 Crash on Launch
61 Crash on Landing
21 Inflight Stall
40 Flew into Something
50 Strong Weather
20 New Glider
21 New Site
13 Failure to Hook-in
01 Mid-Air
08 Aerobatic
11 Structural Failure
02 Flew into Ground
02 Landed in Surf
03 Incomplete Assembly
06 Flew into Rotor
02 Hang Loop Failure
05 Lock-Out

TOTAL
INJURY

18 Head/Face
11 Neck
01 Chest
04 Abdomen
10 Back
06 Pelvis
08 Shoulder
08 Arm
12 Forearm
36 Leg
01 Drowned

1984 USA FOOT-LAUNCH FATALITIES

3/3/84 Marina, CA. Intermediate pilot flying at beach with limited landing area. Misjudged and landed in surf (second flight on new glider), landed in knee deep water. Set glider down and unclipped. Surf flattened glider and despite spectators trying to pull glider out, surf took glider and tangled pilot out to sea.

3/21/84 Santa Fe, NM. During Tetilla Air Races, intermediate pilot flew fast and low through ridge rotor, tucked, tumbeled and dove into ground.

8/14/84 Livingston, MT. Novice (?) pilot launched in ideal conditions, immediately turned to parallel ridge, flying very slowly, continued to turn and flew into the hill (had been warned not to fly so slowly.)

10/23/84 Salt Lake City, UT. Pilot performed 90-degree wingovers at 700 feet when hang-loop broke. Hardware store strap.

1984 USA TOWING FATALITIES

05/07/84 ((1984/05/07 - John Shook)) Sesace, AZ. Intermediate pilot with 30-40 towing flights apparently hooked in only to the towline and when he released at 300 feet, pilot fell to his death.

02/19/84 ((1984/02/19 - Mike Harrison)) Richmond, VA. Novice pilot making his sixth towing flight locked out and failed to correct.

10/21/84 ((1984/10/21 - David Gardner)) Phoenix, AZ. Low-time (novice) pilot locked out shortly after launch. Possible problems with mounting and function of release. Plastic hockey helmet.

8/84 ((1984/08 - Jan Bond)) Saber Nun, CO. Beginner (?) locked out (?).
*
1985/04-04

1984 TOWING INCIDENTS, ACCIDENTS, AND FATALITIES

by Donnell Hewett

Since I try to make it a practice of reporting every towing accident I hear about in the SKYTING Newsletter, you already know about all the accidents I know about. But I thought it might be informative to pull all this information together and try to gain a better overall picture.

When I went back through the 1984 issues to discover how many towing accidents were reported last year, I found 15 such accidents. These are summarized below. Each report summary begins with a reference in case you want to go back and refresh your memory about the details. The reference gives the issue number and the page number. For example, the first reference is #21.1, which means that that report occurred in SKYTING No. 21 on page 1.

INCIDENTS

There were only two reported towing incidents which occurred last year, although undoubtedly there were numerous unreported incidents. This makes it impossible to form any meaningful statistical conclusions. Both of the reported incidents could probably have been avoided if the pilots had been following the standard safety practices of (1) using a weak link, (2) using an observer, and (3) using reialble releases (particularly a single point apex release which cannot tangle with the glider regardless of its attitude). I suspect that most non-reported incidents were not reported because these pilots also realize that they have simply rediscovered some of the mistakes which others have already reported. (I wish they would report their incidents anyway so that we can learn which dangers need to be emphasized the most in order to improve towing safely.) So until additional data is available, I am going to go on record as saying that the major lesson to be learned from the reported towing incidents is: ADHERE TO RECOGNIZED SAFETY PRACTICES WHEN SKYTING.

ACCIDENTS

There were eight accidents reported in 1984. It would appear that the major causes of these accidents were: towing too slow, stall on takeoff, dragging wingtip on takeoff, cross wind takeoff, using unfamiliar equipment, payout winch malfunction, partial two-point release, maneuvering on tow, and novice weight shifting wrong. In other words, the problems were with stalls, takeoffs, equipment, maneuvering, and learning. Again these are all well recognized dangers which demonstrate how important it is to: ADHERE TO RECOGNIZED SAFETY PRACTICES WHEN TOWING.

FATALITIES

There were 7 towing fatalities reported in SKYTINNG last year, but two of these were apparently repeats, so that leaves only 5 reported world wide. Four of these occurred in the USA as mentioned above by Doug Hildreth.

The accident in Canada demonstrated once again that conventional (basetube) towing over land (or frozen lakes) is potentially fatal even to those who are experienced with the system.

The four USA fatalities are a mistry to me. Without additional information it is hard to see how these accidents could have happened.

For example, I can understand why someone failing to hook-in will hold on to the glider when he is running off a ramp or cliff, but why would he hold on when tow launching from level ground? (I - yes, I, too - have failed to hook-in on tow launch, but I never kept holding on to the glider when it lifted off without me.) And even if the pilot did hold on (I admit that strange things can happen when the pressure is on), where was the spotter and what was he doing? Couldn't he see that the pilot was not going prone at the proper altitude? Why didn't he stop the vehicle and/or release the glider from his end?

And concerning the three other USA fatalities - those involving beginner/novices and apparent lockouts - I would like to know what these inexperienced pilots were doing at altitudes high enough to lockout? Were they being pulled so fast that a lockout which started at only at 3 to 6 ft forced them into an arc high enough to roll over? If so, why were they being pulled so fast? What strength of weak link were they using that it didn't break when being pulled that fast?

The questions go on and on... (and will probably never be answered). But until evidence to the contrary is presented, it would appear to me that these accidents were also the result of violating recognized safety practices. Again the message seems to be: ADHERE TO RECOGNIZED SAFETY PRACTICES.

CONCLUSIONS

Doug Hildreth mentioned in his article that the accident statistics seem to demonstrate that hang gliding is maturing as a sport. I wish the same could be said for towing.

The bad news from the towing accident statistics is that the number of towing accidents and fatalities is on the rise. It is obvious that this number is going to rise even higher unless extensive efforts are made now to promote the use of exceptional care when towing and to encourage pilots to adhere to the recognized towing safety practices. To this end, I am currently writing a book on skyting in an attempt to pull together in one publication the information necessary for safe towing. I can only hope that by the time I get the book written and published (any suggestions on how to get it published?) I am not too late to save a few lives.

The good news is that there seems to be no new, unrecognized dangers discovered through the accidents this year and that most (if not all) of the accidents could have been avoided by following recognized safety practices. To me this is very encouraging. It means that most (let us hope all) of the unplesent surprises associated with skyting are now well behind us and that most of the major problems have been solved.

As Doug pointed out in his article, once the solution to the problems are recognized, accidents can be prevented. It has been done in the past, it can be done again. It has been done for free-flight hang gliding, it can be done for tow-launching hang gliding. Let's do it!

1984 TOWING INCIDENTS
(No damage or injury.)

#21.1 CANADA. Pilot flying without weak link and without observer had keel release fail causing glider to rapidly descend. Pilot released at low altitude. No damage.

#22.1 California, USA. Pilot with new glider, new system, unfamiliar harness, and towing for the first time released while turned 180 degrees. Top bridle line snagged. Ground crew tried to keep line slack. Safe landing.

1984 TOWING ACCIDENTS
(Some damage and/or injury.)

#21.3 Kingsville, TX, USA. Ground-looped on cross-wind takeoff using unfamiliar cocoon harness for the first time. Damage: Slightly bent down tube.

#22.4 ISRAEL. New driver. Pilot hadn't flown for 2 months. Bridle under control bar. Not enough speed. Pilot lost control on glider, it turned, nosed in. Weak link (70 kg) broke. Bent down tube.

#23.5 Blenheim, NEW ZELAND. At about 300 ft, bottom release released prematurely while top release stayed attached causing a tuck into inside loop where wings folded and glider flat spun into ground. Pilot sustained concussion and dislocated shoulder. Glider was essentially totaled.

#26.5 Greenvile, MI, USA. Pilot tried several "new things" at once (new winch, line, rough field, untested weak link) and had a determined attitude. On takeoff, line stretches too much, wing drops, pilot looses balance, wing tip drags in brush, glider spins in. Dislocated shoulder.

#29.5 Salinas, CA?, USA. Aerotowing incident. Maneuvering on tow. On completion of left 360, tug turned right. Glider pilot was slow to respond and began lockout to left. Tug and glider corrected, causing slack line which snagged on tug's left wing. Line tightened rapidly, causing second lockout on glider and pulling tug's left wing down, tearing the sail, and causing the tug to invert. Trike fell into wing, left hand upper wire failed, wings folded negatively, and tug spun to the ground. Tug pilot sustained broken wrist and brusing. Glider pilot released and landed normally without damage or injury.

#31.5 Flixton, ENGLAND, Feb. 1984. Towing too slow in wet conditions. Payout winch not acting smooth. Glider slid sideways to ground. Damage: Bent A frame.

#31.5 Flixton, ENGLAND, April 1984. Novice pilot training at 2' to 4' level without tether lines. Pilot weight shifted wrong way, pushed out hard, broke weak link, and ground looped. Damage: small bend in upright, grazed nose, bent keel.

#32.1 USA - HG Magazine. No information.

1984 TOWING FATALITIES

#23.4 Barrhead, Alberta, CANADA. Keel/basetube towing. "Standard lockout". Dived in from 40 meters on a frozen lake 24 km west of town. Had been using this system for 3 years. Pilot killed glider totaled.

#29.1 Arazona, USA.*
#29.1 Virginia, USA.* ((Richmond Hill, Ontario))
#32.1 USA.*
#32.1 USA.*

* See Doug Hildreth's article above for some more information on the United States hang gliding fatalities.
*
1985/04-05

THE SKYTING CHALLENGE

by Doug Gordon
Tempe, Arizona

(Ed. This is a condensed version of an article Doug sent to me which also appeared in the March 1985 issue of Whole Air. Please refer to that article for a more complete description of Doug's views on towing.)

Forteen years ago at the dawn of our sport, many people were taking to hang gliding with the same recless abandon they now take to windsurfing. Back in those early days of garage-made standards and self-taught enthusiasts there were many accidents and injuries. Largely as a result of this, a national organization was formed to bring into focus the goals and aspirations of the participants and increase safety nationwide.

Students were to be rated, instructors certified, and gliders made airworthy.

The sport of hang gliding (almost properly named at that time skysailing) was new. The pilots entering it were virtually all pioneers exploring new facets of flying and glider design. The spirit of comaraderie among fellow pilot was, and still is, high in this small but nationwide adventure. New ideas were seized upon and picked apart at every opportunity to advance the science. Over the past fourteen years, and especially over the last five, glider design has improved to the point where some insurance companies now say that hang gliding is safer per hour than snow skiing.

In 1980 a physics professor by the name of Donnell Hewett put forth an analysis of a new system for getting our heavier-than-air gliders into the sky, which one day may very well be viewed from an historical vantage to be just as important as all glider design improvements combined. Certainly center of mass (skyting or partial center of mass (one release line at pilot) will within twenty years become the dominant form of getting hang gliders into the air. It's not simply a question of who is or who is not interested in towing. The relevant question is what percentage of potential pilots across the United States live close to mountains and what percentage live near an open field or body of water. The answer, of course, is that the vast majority of people live nowhere near mountains. This does not mean, however, that skyting will replace footlaunching. It should not and will not. What it will do is add an excellent supplement to our sport. It is the key - along with the newly approved FAA exemption for air-to-air ultralight towing - which now allows anyone living anywhere in the country to become a hang gliding enthusiast.

Towing must be made safe. History shows us that once a technology has been devised and information about it freely disseminated to a population, it is then impossible to take back. This is especially true of skyting because the cost factor for a skyting system is incredibly low.

For skyting we need a revival of that early spirit of picking up the ball and running with it. We all need to work together to develop it safely. What we don't need is resistance to change and bureaucratic knee-jerk reactions. More importantly, if we set a high rating to tow, then how are pilots from mountainless states going to get from hang zero to hang 3 without skyting?

Nerly all traditional (paid) teaching in hang gliding is for first-day beginners through hang 2. Once a student attains the hang 2 level and begins mountain flying, he generally will join the local club and practice to gain the higher ratings. This is why the USHGA certifies basic instructors to rate hang 1 and hang 2, and observers to rate hang 3 and hang 4.

Moreover, unless economies of scale are created by an extraordinarily higher percentage of the U.S. population becoming hang glider pilots, it will not be profitable to start an aero towing hang gliding business in even our largest cities. It is even this author's opinion that aero towing will probably never take on the number of enthusiasts that vehicle towing will. The reason is simple economics. Aero towing is quite expensive and over 80% of thte persons in our sport are males in their twenties, usually early twenties, a group notoriously short of disposable income. An aero tug can cost upwards of $5,000; for under $500 you can get a complete skyting system with a tension gauge and voice-activated two-way radios. Any number of members in even a small hang gliding club can pool funds together for this purpose. Furthermore, land towing (skyting) has already proven its potential. This past summer Joe Greblo flew Delta Wing's fantastic Streak 151 miles after a tow launch!

I believe that the answer to the towing dilemma is to devise a system which is safe for hang 1 and hang 2 under supervision. What we could do is educate pilots through publications and books on the best methods to date. We could start certifying skyting instructors at every ICP (Instructor Certification Program). We could start making extensive use of lists during pre-flight like they do in every other form of aviation. We could start a tradition of the flight director being the unconditional boss at launch; if someone doesn't meet his skyting criteria, he doesn't fly.

What we don't need at this point in time is another factor which would lead to dissatisfaction of pilots and a drop in USHGA membership renewals. Whatever rules are eventually drawn up for land towing, they must be agreeable to the vast majority of pilots on a voluntary basis because these pilots see these rules to be in their own best interest. Pilots should understand the inherent danger in towing. There are more variables, therefore the number of possible consequences is greater. Most of the reported accidents in towing recently have happened to hang 1 and hang 2 pilots, but this statistical reality does not encompass the fact that the majority of accidents occur due to a lack of supervision, not rating. There is a lack of supervision because there are only a few people across the entire country who know enough about the frontier knowledge in skyting to be able to teach it safely.

In teaching hang gliding by towing, I do not mean to indicate that skyting is as safe as footlaunch instruction. It is not, and probably never will be, since there are more variables involved. I do think a skyting system has been developed which brings the safety level well within the acceptable range.

Most advanced pilots who have tried skyting and are convinced that a hang 3 rating or better is needed to tow because they need their advanced skills in order to skyte safely, have skyted on their Comets or other floating crossbar gliders. If one does not already know by now, the difference between skyting with a non-floating crossbar is like night and day. The difference between skyting with just about any other glider and a Seagull Seahawk Trainer is even another order of magnitude easier. Those Seahawks just don't want to turn and they have an incredibly low minimum flying speed; as long as they're in line with the wind/vehicle pull direction, they gently go straight up hands off. As soon as the student is comfortable with skyting on a Seahawk, I put him on Delta Wing's new Light Dream. Besides, having a small, easy to handle control bar and light weight, the 165 model has the option of a lock-down crossbar which is essential for skyting. To my knowledge, the Light dream 165 is the only glider currently produced with that feature which makes it the only modern glider available for a skyting class.

Skyting is primarily for teaching, getting the feel for towing, and recreational flight up to hang 3. Advanced pilots don't need to skyte. They can tow using a single release at the pilot's shoulders which does away with many of the problems associated with a skyting system. In fact, a single release at the pilot negates the adverse yaw skyting effect on a floating crossbar glider. Be aware, however, that this kind of towing does require advanced skills and a French connection does help to control the glider in its resulting out-of-trim condition. This is because a single release point on the pilot does not take into account the center-of-mass of the glider and can result in serious pitch problems. The aero towing people have been using this system for over a year with fine results.

The opinions of people in the hang gliding community in terms of what level of proficiency a pilot should be allowed to skyte run the full gamut. There are those who believe in a minimum hang 3, some are for hang 2, some are for hang 1, and there are those who believe a person can learn how to hang glide by skyting from day one. I'm about the middle of the road on this one. My opinion is that hang 1 level is necessary to skyte safely. I think that most instructors would agree that there is a vast difference between a person who has never picked up a hang glider and a person who has three days of experience in their abilities to fly, land, and adjust air speed, and most important, in their confidence in doing so. Even flat, mountainless states have some small rolling hills or sand dunes. It shouldn't be too hard to get a couple of days experience first. The reason I don't think a first-day person should tow is because there are just too many variables for the beginner pilot to remember at the same time. For example, when someone is taught any physical skill, whether it is hang gliding, tennis, golf, or skiing, behavioral responses must be added one, or at most, two at a time. Even athletes cannot remember to do more than two physical actions at the same time if they have never done either before. Transfering what one knows in one's mind to the fingertips for the first time is not an easy matter for anyone. That's why a good instructor will start beginners low on the trainer hill and let them work their way higher at their own pace. A student should feel quite comfortable at a specific level before going higher. A first-day beginner on the shallow end of a trainer hill has more than ten things to think of as he jogs down the slope for take-off the first time. Add to this a tow force of 100 pounds, a release, all of the skyting safety rules, and the phychological effect of being pulled by all those horses, and it becomes obvious why learning from day one by towing is just too much for most people. If there is enough time, energy, and the proper equipment, it might be possible to teach first-day people to skyte safely if they were being towed aloft by a boat over a lake, since water is a much safer medium. This mehtod, however, would not be cost effective from a business point of view due to the time element per flight. Even land or aero towing (if it were safe for first-day beginners) would not be cost effective for them because it takes so long between each tow, and students require so many short-hop flights to get the feel of the glider and skyting.

Skyting has solved the problem of getting pilots from the small trainer hill to the mountain flying and does this in any wind direction or no wind at all. It now appears the problem of getting pilots from no experience to hang 1 is solved. Recently in Europe a rather unique system was developed which works without hills or towing, in any wind direction, or with no wind at all. What they have done is develop a device which is flat mounted on the back of a flat bed truck in which the glider fits, and which limits the glider's axis rotations. They simply point the truck into the wind and accelerate until air speed is attained. Flight simulator is not the right word since the pilot is actually flying. Flight limitator would be much more descriptive. Of course, this type of system does not take into account take-offs and landings, but never-the-less getting the feel for a glider by being able to fly for such an extended amount of time as a beginner would almost certainly qualify a person for low skyting flight. If what I've heard about this system is true then, together with skyting, the major problems of hang gliding instruction have been solved.
*
*

[Tad Eareckson]

1985/05
*
SKYTING NO.37
MAY 1985
*
1985/05-01

SKYTING SAFETY RULES

by Doug Gordon
Tempe, Arizona

(Ed: These rules were presented with last month's article "The Skyting Challenge" but were not included there because of space limitations.)

Skyting is a form of hang gliding in which the glider and pilot are towed to altitude in a way which distributes the towline forces between pilot and glider proportional to the masses of each. The net effect is that two-thirds of the pull is on the pilot and one-third on the glider. The three factors of towline tension are vehicle speed, wind speed, and glider pitch. These three factors are reflected as one figure on the tension guage dial which the tow vehicle reads as he tows. If the tension increases too much, the driver lets up on the gas. A weak link is employed on the line as a fail safe.

The Eight Skyting Criteria:

1. Constant Direction: Skyter sidesteps glider directly behind vehicle pull direction (into wind).

2. Constant Tension: Vehicle driver watches tension dial for constant pull.

3. Proportional Distribution: Skyting bridle solves this as mentioned above.

4. Attachment Points: The keel ring and body ring should be located as close as possible to the center of masses of the glider and pilot, respectively (i.e. control bar bracket; waist of pilot).

5. Slow Transitions: Use 300 feet of elastic towline (100% nylon) to stretch in order to guarantee that the towline tension varies slowly.

6. Reliable Release: Three ring releases work as tension increases.

7. Weak Link: This is essential for towing so G-forces cannot build up under any circumstances. Remember "Murphy's Law." 200-pound test maximum.

8. Safe Learning Method: Become expert in low and high winds at a low altitude before flying higher. Don't teach beginners hang gliding by towing.

Skyting Safety Rules

A. Connections:

1. Hook up - hang check - helmet on tight.

2. Rope straight to vehicle - hook up bridle release.

3. Hand to ripcord - topline clear of helmet.

4. Pilot pulls back for tight line and sidesteps in line with vehicle wind.

5. Launch director rechecks hook in/bridle/release/towline/wind direction.

B. Verbal to Pilot by Launch Director:

1. Keep the nose positive.

2. Keep wings level as you can.

3. Pull in as you lift off. As you go higher pull in harder! (Wing gradient.)

4. Keep glider directly behind vehicle.

5. Try to relax and think air speed (i.e. pull in).

6. Pull in, then release (Your body should be through control bar as you release.)

7. Keep bar pulled in for a moment to pick up air speed after release.

Basic Safety Concepts:

1. Do not push out at any time while glider is under tow!

2. Launch director signals driver to start (hand signal or radio).

3. Always hold downtubes for take-offs and landings (within 50 feet of ground - watch windsock).

4. No turns within 50 feet of ground - watch windsock.

5. Fly faster as you near the ground - 20 feet (wind gradient).

6. Relax - make small, smooth control inputs.

7. Think air speed - keep that bar pulled in.

8. If you want to go higher, simply pull in less hard.

9. Do not practice flying skills while under tow. Keep glider behind vehicle and in constant tow force. (Skyting is a necessary evil to gain altitude only.)

10. The idea is to be able to release or at least to slacken towline the instant the pilot wants to, therefore:

A. Do not tow up past a 45 degree angle (if vehicle stops, towline slackens).

B. Keep glider behind vehicle (by pulling in pilot slackens towline).

11. Even if weak link or towline breaks, pilot still must release his end!

12. Towline touches glider wire - do not release yet (possible tangle).

13. Do not take your hands off the downtubes until you have released and are free flying.

14. Launch director is unconditionally the boss. If a pilot does not meet his skyting criteria list, then he doesn't fly.

15. Use wheels! Walk glider back on - saves bad take-offs/landings.

16. If release won't release or line tangles, use voice-activated radio to signal driver.

17. Have fun!
*
1985/05-02

CHALLENGING THE CHALLENGE

(Ed: I believe that open communication between persons of varying views is not only desirable but also essential to the process of filtering out the best ideas associated with towing proceedures. This article and the one that follows next month are exerpts from letters Doug and I have sent to one another as follow-ups to his article "The Skyting Challenge." They are presented here and next month both to keep you informed about our respective viewpoints and to encourage you to send in your own viewpoints on these and other issues associated with skyting techniques.)

Dear Doug,

I enjoyed the article you sent me and am in almost total agreement. Since there is little point in restating everything we agree on, let me mention a few areas of disagreement and ask for your comments on these areas.

WHICH IS SAFER?

I generally agree with your statement that skyting is not, and probably never will be, as safe as footlaunch, since there are more variables involved. However, because skyting affords more control over the variables, skyting can be safer than foot-launching.

For example, suppose something goes wrong immediately after takeoff. A footlaunch pilot has no choice but to fly down the whole hill while a skyting pilot can choose to abort and land. Another example is cross-wind takeoffs. They are certainly safer when skyting than when foot launching. My belief, therefore, is that skyting can be both safer and more dangerous than footlaunching - depending upon the situation.

Although the accident statistics show that towing is currently more dangerous than footlaunching, I believe that this is a result of "growing pains" and not "inherent character." It is not clear at this time whether the increased danger (due to increased complexity) will dominate or the increased safety (due to increased control). It may well turn out that future skyting can be made safer than footlaunching. Only the future statistics can tell for sure.

AB INITIO TRAINING

In regards to towing beginners, I am one of those on the extreme, who believes that under proper supervision, skyting can safely and cost effectively be taught from day one. The reason I am convinced of this is that this is exactly the area of training in which I have had the most experience. Almost everyone I have taught to skyte has been a beginner (who almost always moves away before becoming experienced), and my safety record with beginners is as good or better than with experienced pilots.

I don't have time to outline my whole beginner program (perhaps I can do so in a future issue of SKYTING), but essentially it is as follows: (1) Movie or actual demonstration of skyting. (2) Ground school theory and dangers (emphasizing the dangers of stalling). (3) Ground school simulation (hanging in a control bar with me simulating flight forces). (4) Ground handling of hang glider. (5) Simulated takeoff (never leave the ground) with human tow. (6) Simulated takeoff with vehicle tow. (7) Takeoff (1 ft altitude). (8) Takeoff and landing (3 ft altitude). (9) Takeoff, level off (at 3 ft), landing. (10) Takeoff, level off (at 6 ft), descend, land.

Every step must be mastered before the next is begun and no tendency to stall should be evident. By the time a student has reached this level, he is a good hang 1 and should be qualified to begin your program.

One other comment. If at all possible, (and it usually is) I give the student actual flight experience before step 7 by kiting (tethered skyting) in 15 - 20 mph winds using a nose line to limit flight. This is the fastest and safest way to learn how to control a hang glider on the ground and in flight. It is my "poor boy's flight simulator". (Actually, flight limiter.)

Although I usually instruct one on one (because of limited students), I have - and actually prefer - a class of about five students. This permits each to learn by watching the others, to rest between tasks, and to learn to do each part of the ground crew's jobs in the skyting operations. Once actual flying begins, each student makes several short flights before stopping. Learning is faster and with less fatigue when skyting than when having to carry the glider back up the training hill after each flight. In short, the economics should be as good or better for skyting beginners as for footlaunching beginners.

PULLING IN

I agree that near the ground it is important to fly faster than normal to prevent the possibility of stalling. However, it is possible to pull in too far and thereby make it harder to control the glider. Too much pulling in can actually increase the danger. Here an experienced instructor is needed to gauge the amount of pulling in that the student should be doing.

You are not the only person I have heard say, "Do not push out at any time while the glider is under tow!" I can understand saying this when instructing beginners or novices. But once the pilot is qualified to tow to altitude, I cannot understand why this rule is suggested.

If the skyting system is properly designed, flight is the same as free flight under simulated gravity. Therefore, pushing out is just as appropriate while on tow (or just as inappropriate) as when free flying. I would appreciate your telling me why you feel this rule is so important that you underline it.

TOWING PAST 45 DEGREES

I agree that beginners and novices should not tow past 45 degrees lest they overfly the vehicle without releasing, but I see no reason an experienced skyter should not do so. If you feel otherwise, please explain your reasoning to me.

RELEASING IN A "LOCKOUT"

In a potential "lockout" situation, while towing with a good threaded release or an apex release, the danger of entanglement is less than the danger of staying on line. One should not release near the ground, but at altitude one should release in many cases. Beginners and novices should not release, but experienced skyters should release when it is appropriate.

KEEP ON COMMUNICATING

Doug, as you can see, our points of disagreement are very few and generally minor. If you feel strongly about any of these matters, please write a letter to SKYTING so that others may hear your views. I frequently print opinions that differ from my own without comments so that others besides myself may have a voice in the Newsletter. There is no doubt in my mind that you have more experience than I in actual skyting instruction, so your opinions may well be better founded than my own.

Donnell Hewett
+
KEEP ON COMMUNICATING

He says Go Go!

No No!
*
1985/05-03

HOBBS SKYTING TOURNAMENT

Dear Donnell,

Here's an update on the Hobbs Skyting tournament scheduled for June 13-16th. First of all, we have gotten the support of the city and area businesses so the financial part is quickly falling into place. The USHGA has been very helpful and will be sanctioning the event. I say will be because I haven't finished all the paper work. The easiest way to do this might be to just list out the various points of each area.

PRIZE MONEY?

Yes, and we are well on our way to having over $1000 in prize money. We'll have an absolute figure after the 15th of May.

PILOT REQUIREMENTS:

1. USHGA (current) membership.

2. Hang 3 rating or be able to demonstrate to our safety director competent launching technique.

3. $45.00 entry fee per competition pilot. This entry includes 4 tows/day during competition. Extra tows at $1.50/tow.

4. Pilot must have CB radio communication with ground crew and officials. We think CB will be the cheapest way to go.

5. Non-competition pilots entry fee $35.00. Will launch only after competition pilots as safety dictates. Competition pilots are allowed 3 launch attempts without point penalty. After second attempt, however, pilot must go to the end of the competition launch line. Four unsuccessful launch attempts disqualifies a pilot from the day's task.

6. Pilots supply their own bridle and release system, which must be demonstrated to the safety director.

7. Pilot may use his/her own ground crew for towing, otherwise we will supply a driver.

8. Tow lines will be supplied. DEADLINE FOR PILOT REGISTRATION , MAY 30, 1985.

COMPETITION TASKS

DAY ONE, June 14th.

ON THIS DATE WE HAVE CHOSEN AN OUT & BACK COMPETITION. Pilot will launch and their time will start at release. The task will be from the Hobbs Industrial Air Park to a predetermined point and back to the park. Pilots will need 110 camera to photograph the turn point. On of our sponsors will sell 110 film at cost if you need it. The TET format (Total Elapsed Time) will be used to determine points for those pilots landing out. This system will be explained at the meet. Pilots should have a radio equipped chase vehicle lined up.

DAY TWO, June 15th.

ON THIS DATE THE PILOTS WILL FLY A PRE-DETERMINED TRIANGULAR COURSE. Generally, the same format will be used, but the flying will be kept closer to the air park area so our specators will be able to see more of the competition.

DAY THREE, June 16th.

AS OF THIS WRITING WE HAVE NOT SELECTED A TASK. The previous two days may prove to be enough for our first major skyting competition. Sunday will probably be fun flying day for most pilots. Pilots coming into this area might want to take a day to visit the famous Carlsbad Caverns which are a little over an hour to the west.

Aero towing may be allowed for demonstration purposes only. For this competition, competitors must ground tow. All certified gliders are eligible to compete.

For entry forms or information, call or write Merlin D. Zimmet, 2400 N. Grimes H-170, Hobbs, N.M. 88240, 505-392-4552 (work, KHOB radio), 505-392-4239 (home).

P.S. We are limiting this to 30 pilots. Merlin D. Zimmet
+
THE HOBBS NEW MEXICO SKYTING TOW TOURNAMENT
JUNE 13 THRU 16
NORTH OF THE CITY AT HOBBS AIR PARK
COMPETITION ENTRY $45
FUN FLYER ENTRY $35

Pilot requirements

1. current USHGA membership
2. Supply own bridle system
3. CB radio communication
4. Safety chute
5. Hang 3, or safe launch demonstrated to safety director
6. 110 camera

FOR INFORMATION OR ENTRY FORM, CALL OR WRITE
MERLIN D. ZIMMET, MEET DIRECTOR
2400 N. GRIMES H 170
HOBBS, N.M. 88240
KHOB 505 392-4552 or
Home 505 392-4239

Entry deadline
May 30
USHGA SANCTIONED
$$$$ AWARDED
FIRST THREE PLACES
This is a sponsored tournament with prize money not contingent upon entry fees
*
1985/05-04

A KINGSVILLE VISIT AND SOME MINNESOTA SKYTING

Dear Donnell and Family,

Thank you all for the generous hospitality the family had shown us on our visit to Kingsville. Two days ago I mailed the flying movies and video tape of our summer and winter flying operation. I hope you don't laugh yourselves sick at our early attempts to commit aviation. The video has yet to be edited. Note the best landing on it is by the lady of our operation. Don Ray had stamped a ten-foot bull's eye in the snow and placed a glider bag in it. Terry, as you can see, landed exactly on the bag. John Gervasio, a retiree from Hoyt Lakes, shot the video and made a copy for us.

My partner, Gene Stone, has modified my three-ring release by cutting the middle ring off, leaving only the biggest and smallest rings. He melted the nylon where he had cut it so it wouldn't unravel. This makes it into a simpler and safer 2-ring release. If you use the one I left with you, get a bigger ring or do as Gene did.

Terry, Don, and I met Gene Stone and his friend, Homer, from Grand Rapids, Mn., at Swan Lake for some snow machine towing today.

Terry found a winter thermal and gained 400'. When she left it to come back to the lake she couldn't make it back. What looked like a tree landing turned out to be a good landing in a small field. She had released at 1480' AGL. Gene gained 300'. Don and I launched just in front of an incoming cold front which took us both to 2900 AGL. We had released at 1600' AGL and 1800'.

You might think my first day's high-flying thermal flights, during our visit with you, would be the highlight of the trip. For me it was tether flying at Fantasy Island (Padre Island). When you and Terry unhooked the tether line from the van and took me for that walk down the beach, it awakened a long-forgotten memory of a fantasy I had as a small boy - to be at the kite-end of a string.

"Wouldn't it be great to be on the kite looking down the line at the people?" I remember saying. It was!

Bill Cummings
*
POWER WINCH BEING BUILT IN OHIO
*
1985/05-05

Dear Donnell,

I'd like to take this opportunity to tell you about the stationary power which I'm putting together. I hope to have it functional by early summer. When operational I plan to use your Skyting Rules and natural laws to try to keep things as safe as possible. We do have a few people here with some experience in auto towing and my brother, Glen, plans to see you this month to get some first hand knowledge himself. So, hopefully, we will have a lot of fun and few problems as we develop our program.

I feel a need for a stationary winch for one big reason and that is space. Unlike Texas or the Middle West, we here on the north coast are wired in by power lines everywhere. It's hard to find long open places to auto tow with any degree of success. Water towing doesn't appeal to me either. Lake Erie is kind of rough, in my opinion anyway. So by using a power winch, tight places can be used to their fullest with a winch at one end and the kite at the other. Also, fewer people can operate the system without any extra safety risk.

In building my winch I've come across a couple of problems. I believe I've worked them out but I'd like to tell you about them to see if I'm right or if you have any suggestions.

Both problems have to do with towline tension. One is how to monitor the tension. The other has to do with a limiting device.

First, I'm running my tow rope through a set of pulleys (diagram), one being locked to a hydraulic cylinder by a moveable lever. This I hope to use to monitor tow tension so the operator can adjust speed accordingly.
+
Kite
fixed
LEVER
Gauge
Reel
+
To test this setup I locked a set of pulleys together in a similar manner, using a fish scale. As suspected, the pulley hooked to the scale reads twice the amount actually applied (hanging 2 lbs on the rope reads 4 lbs on the scale). My conclusion is: Make the lever between pulley and cylinder a 2:1 ratio.

Next, the bore on the cylinder I'm using is approximately 5/8" diameter. Calculating area of a circle and applying basic principles of hydraulics, I figured there is a 2.8:1 ratio, meaning that for every pound applied directly to the cylinder the guage reading will read 2.8 times higher.

Taking this ratio (2.8:1) and the ratio in the first part (2:1) and combining them, I believe the total ratio of the two should be 5.6:1 as in the next diagram.
+
Cylinder
5.6"
1"
To Reel
To Kite
+
How am I doing so far?

Once I have the system together I will check this and calibrate it by hanging a weight on it and adjusting lever length. The only other concern I have with this is: Will doing this in a static setup be the same as when set in motion (higher or lower guage readings, at what %)?

The other problem, as far as I can see, will be a compromise. As an added safety factor, I've incorporated a slipping clutch device called a Browning Torque Limiter. This is intended to come into play when too much tension occurs too quickly for the operator to compensate. This unit is adjusted to a predetermined setting and will start to slip if torque values exceed this setting and stop slipping when brought below this setting.

Where the problem occurs is as the tow rope is taken in the diameter of the reel increases, thus increasing the load on the torque indicator. To demonstrate this I'll use my setup as an example. The reel I'm using has a 3-inch diameter. It is 3 ft long and has 3-inch sides, making total diameter 16 inches. I estimated it will hold about 3000 ft of 1/4 inch polypro.

The torque limiter mounts on the same shafe, going through the reel. It has a sprocket diameter of 8 inches to which a roller chain attaches to the power source. See diagram.

Reel
Torque Limiter
Power
A
B
C
D
F
A
B
C
D
F

Applying some basic science to this setup I see a simple lever and fulcrum, the center shaft common to the reel and torque limiter as the fulcrum and radius of the reel and torque limiter sprocket as the outer limits of the lever. The law of equalibrium states EXAB=FXBC. So let AB equal the radius of the torque limiter sprocket (4 inches) and BC the diameter of the reel and rope as it is wound in. The amount of the force (F) will be 200 lbs when solving for (E), the setting for the torque limiter. You can see it changes as the reel and tow rope diameter increases. If you roll in half the rope, as I estimate, you are talking a 75 lb increase in tension to the torque limiter. Quite a bit, I think. As I said before, the only solution I see is to compromise by spliting the difference, that is, set the torque limiter 35-40 lbs higher at the start where the reel is at its smallest and as you reel the limit will be approximately 35 lbs, lower than the preferred setting but still functional.

Well, that's it. Tell me what you think. I hope I've brought up some important questions to deal with when considering a power winch. As things progress I will keep you informed and write again.

Mark Nicolet
Thompson, Ohio
*
1985/05-06

Dear Mark,

Thanks for writing and renewing your subscription. While your brother Glen was visiting with us here this weekend, we discussed your questions fairly thoroughly. So when he sees you he should be able to explain things better to you than I can here in this brief letter. Never the less here are some thoughts I have on the questions you raised.

1. Concerning your pully-lever-hydraulic tension gauge, I see nothing conceptually wrong with the design. However, to me it seems more complicated than necessary. For example, you can completely eliminate the lever by using a hydraulic cylinder of the proper diameter. Or if you want to use the cylinder you already have, you can simply re-calibrate your gauge by marking it a the proper tension settings.

2. Yes, the static set up will read the same tension values as when set in motion. After all, the tension measuring device (hydraulic system with gauge) has no way of knowing that the rope is moving through the pulley. Of course, there are dynamic properties of the moving system that affect the tension differently than in the static case - primarily the inertia of the drum and rope - but the gauge still reads the actual tension pulling in the towline.

3. Unless your system is grossly overpowered, your torque limiter is an unnecessary duplication (as far as safety is concerned). The engine itself will limit the tension to safe levels even when the winch operator reacts improperly. And the weak link in the towline will release the pilot from tow in the event that "everything possible" goes wrong.

4. Actually, if it were me, I would do things backwards to what you have described. Instead of using dynamic tension regulation (human control according to tension gauge reading) with a torque limiter as a back-up, I would use the slipping clutch to automatically regulate the tension and a human operator as a back-up. (Of course, the torque limiter would have to be calibrated properly and tested for reliability and consistency.)

By using the slipping clutch as a tension gauge, you not only eliminate the human element (and the need for a separate tension gauge), you also eliminate the various gears needed to supply adequate power at various speeds. Now the engine can run at full power at all times while the clutch slips however much is needed to compensate for the various speeds of the glider and the wind. Of course, you will have to have a clutch sturdy enough to withstand continuous slip, but that should be no major problem. And you will have to have sufficient power to pull the towline faster than the glider ever flies, but you would need that power anyway.

5. Yes, you are right. The torque limiter does not provide constant tension as the winch winds in more and more rope. There are several ways to compensate for this:

a. Set the torque to supply the average tension (as you suggested). The +/- 40 pounds is pretty large (especially for takeoff) but not too large to be handled safely as long as certain precautions are taken. For example, when in doubt, set the tension on the low side - lest you have a pop start on takeoff. This is because the +/- effect is in the wrong direction for ideal towing where you need less tension as you climb out. In any case, on takeoff you will need to let the engine rev up to full power and then engage the clutch slowly so the pilot can launch smoothly.

b. Use a smaller diameter towline - specifically 1/16 inch steel cable. It will change the take-up diameter very little for the same amount of line. The tension will, therefore, vary very little.

c. Use dynamic tension regulation as a supplement. Simply let the winch operator increase the tension setting as the glider climbs higher. If your system is designed right, this should require nothing more than turning a dial or pulling lever.

d. Or you can use a combination of all three of the above.

6. One final thought. If you really want first hand knowledge from experienced power winch towers you should contact the skyters in England. Write Tony Webb, c/o Lezair ((Lejair)) Hang Gliding Tow School, 41 Kinsdale Drive Thurby Lodge, Leicester, ENGLAND LE5 2PS. I am sure he will be more than happy to communicate with you.

Donnell Hewett
*
WATER TOWING INFORMATION WANTED
*
1985/05-07

Dear Donnell,

I recently purchase a new 1984 Vision 18' from Kitty Hawk Kites East and was talking with Ed Miller there (he now works for Pacific Windcraft) and told him we were going to be towing behind a Master Craft ski boat. He told me you published a newsletter, called Skyting, which would have pertinent information to boat towing. I'm a novice pilot and any information, especially on towing, would be very helpful in allowing me to live a long life!

There are a couple of items that I'm looking for that maybe you can help me with. Since I am towing and I'm a novice pilot, I feel most comfortable with both hands on the control bar at all times. Since the danger of lockout exists in towing, I feel a voice-activated headset with a CB would be a nice setup. The CB would come in handy for high mountain flights which I hope are a part of my future. I've had no luck in finding a voice-activated headset. Can you help? The FM frequency radios do have a voice-activated headset, but a range of only 1000'-1500' which would be fine for towing but not for mountain flights. My last resort, I suppose, would be a headset with a push-to-talk switch. My only concern would be: If in a lockout situation would you be able to reach the push-to-talk switch?!

We do deep water starts and are presently using a 300' rope which we feel comfortable with. I'm wanting to go to a 1000' rope for higher altitudes. Do you think at 700'-800' altitudes I should use a parachute? And if so, is there one that is compatible with deep-water starts? (I'm flying in the prone position and partially submerged during takeoffs and landings.) How about a ballistic type chute?

One more question and I'll let you go. What do you think about the quick-release carabiner I've seen advertised in "Hang Gliding" magazine? If a possible total submersion should occur, don't you think this would be a good idea to get out and away from the glider?

Steve Lady
Bristol, TN
*
1985/05-08

Dear Steve,

Thanks for expressing an interest in skyting. I will try to answer your questions in the space below.

1. Enclosed is the information you requested on the back issues and subscriptions to SKYTING.

2. As a Novice it is essential that you read ALL back issues of SKYTING before attempting to tow with the skyting method. If none of your friends have these back issues, order your own copies.

3. Unfortunately, very little information on water towing is contained in the back issues of Skyting. One reason for this is that most water towing today is still performed by pilots who use the old system and who generally do not communicate with others through the SKYTING Newsletter. Another reason is that beach launching is the same whether towed by boat of by car. And a third reason is that water towers who try land towing rarely go back to water towing because of the expense and inconvenience.

Let me quickly list some of the things you should know about water skyting (see back issues of Skyting): (1) Use floats. People have been killed flying over water without them. (2) Use a harness designed for deep water starts. Regular harnesses will make the floats sink by holding you to high. (3) Use a double release at the boat with the weak link between them. Release the first release after the glider is airborne so that the rest of the flight is on a weak link. (4) Use a single-point apex release bridle which stays with the glider after release. (5) Practice "water handling" the glider in shallow water with the wind blowing. You will probably be surprised how difficult this is. (6) Practice being dragged behind the boat. You will notice that the control inputs are backward to what you would normally expect (i.e. body right to turn left). You will have to PUSH on the control bar to make the glider go forward. You will have to LIMIT the keel line movement or it will pull the nose of the glider over into the water. (7) Practice controlling the glider in deep water with the wind blowing. You don't want to let things get out of hand, flipping the glider with you attached. (8) Once you can control the glider in the water before takeoff and after landing, you are in good shape to proceed with skyting. In the air, the glider responds normally. (9) Take care to gradually advance from one level to the next. (10) Be safe.

4. In SKYTING No. 26, Don Boardman, 6433 Karlen Rd., Rome, NY 13440, was selling a CB VOX unit for $115 including a one year warranty. I doubt that it is designed for water towing (i.e. getting wet). For that matter, regular CB's are not designed to get wet either.

5. In a lockout situation, you should NEVER try to talk to your crew - YOU SHOULD RELEASE! Then you can worry about talking. If you place a push-to-talk button on the base tube beside your hand position, you can instruct your driver without taking your hand off the control bar. You can also mount a push-to-talk button on a glove and activate it with your thumb regardless of where your hand happens to be at the time.

6. A parachute should be used at any altitude above 100 ft (saves have been recorded that low). However, I do not know of any water-proof parachute system, and a wet parachute is quite likely to fail to open. Furthermore, if the parachute gets wet, it has to be opened up, dried, and repacked again before being used. I suggest that you learn to fly without a parachute and then take off and land from the beach so you do not have the wet water problems. A ballistic parachute on top of the glider (assuming it does not turn over in the water and get wet) might be the best way to go (except for the expense).

7. I have no first-hand knowledge about the quick-release carabiner, but I can tell you that when I ever get around to boat towing I am going to make sure that I can release from the glider quickly while suspended in the water. In other words, I believe I would use one. I firmly believe in "stacking the deck" as far as possible in the direction of safety, and in taking precautions against all conceivable problems. After all, one form of Murphy's law is: "Anything that CAN go wrong WILL go wrong!"

Donnell Hewett
*
1985/05-09

HEWETT'S LATEST BRIDLE CONFIGURATION

by Donnell Hewett

I have never been quite satisfied with any of the skyting bridles that I have used. There always seems to be one or more features that simply do not suit my own personal tastes. So I keep trying new designs, hoping to find one that I really like. The skyting bridle described below and illustrated in Figure 1 is the result of my latest attempt to design a bridle for my own personal use.

Actually, there is nothing radically new about this design. It is simply an attempt to incorporate into a unified bridle what I perceive to be the best ideas which various individuals have suggested, and to eliminate (or at least to reduce to a minimum) the dangers, problems, and inconveniences which previously have been associated with other bridle designs. The goal has been to design a bridle which I personally find satisfying - namely one that is (1) as safe as possible, (2) reliable, (3) simple, (4) convenient, and (5) inexpensive. Whether or not this goal has been achieved, only time will tell.

KEEL RING

I have attached my keel ring permanently to the shifting crossbar of my Gemini 164. So far this has been quite satisfactory in eliminating the adverse yaw effect and producing flight characteristics on tow essentially identical to those of free flight. My only concern is that the glider's shifting crossbar mechanism was not designed for such a load pulling down on the crossbar. Needless to say, I am on constant alert for signs of wear, stress, and/or binding in the shifting crossbar mechanism.

EXTENSION LINE

I use a keel extension line (about 5 ft long) to locate the front manual release just below the flying wires of the glider. This is more convenient than placing it at the top of the keel line. Specifically, it allows the front release to be activated while flying prone. Furthermore, it lets the pilot get rid of the keel line while topping out on tow by releasing the front release and holding it in his hand on the control bar base tube. Once the front release is activated, the wind blows the extension line out of the way of the pilot's view and movements.

FRONT RELEASE

The front release uses one of the original "horse bridle" releases and is activated manually by the pilot in the prone position. It is normally activated AFTER the pilot has released himself from tow using the more reliable apex release discussed later. However, if the pilot wishes, he can release the front release while on tow and hold it in his hand as described above. This is done ONLY at large tow angles in order to get the keel extension line out of the pilot's way. If the pilot does not hold on to the front release after releasing it, the apex release will automatically release the glider from tow as the main release line grows tight. This auto-release feature will also occur if the front release prematurely releases or if anything breaks or fails in the keel line system. This prevents the pitch up/whip-stall problem some people have reported when something causes the keel line to release while under high tension tow.

MAIN BRIDLE LINE

The main bridle line (about 15 ft total length) is make out of flexible non-stretch line. I am currently using 11 mm Perlon mountain climbing rope but may try 3/8 inch polypropylene rope which is cheaper and makes a neater package when threaded into itself to make a loop in the end. It is essential that there be little or no stretch in the bridle line or else it will fly back into the pilot's face when the weak link breaks (or when releasing under high tension).

BODY RING

My body ring is sewed permanently onto my harness right below my parachute. Other pilots use a body ring attached to a rope or webbing hooked to the bottom of their hang straps. But this configuration did not work well with my particular harness-parachute arrangement.

BODY RELEASE

The body release is another "horse bridle" release and is also activated manually when the pilot wants to let the bridle drop away. Before releasing the body release, the pilot needs to (1) release from tow using the apex release, (2) release the front release, (3) slip the hand loop off his hand, and (4) then release the body release. If he releases the body release first (while still on tow), the apex release will automatically release him from tow when the release line grows tight. This auto-release feature will also function if the body release accidently releases for any other reason. This prevents the pitch-and-tuck problems others have experienced with a premature body release while towing under high tension.

HAND LOOP

By looping the main release line on the pilot's hand, he does not have to reach for it in an emergency. Yet he is able to move his hand wherever he wants on the control bar. Another advantage in having the release line looped on the pilot's hand is that he can easily release himself should he fail to hook in on takeoff.

One of the problems I have found with this arrangement is that when the pilot goes from erect to prone (and his hand moves from the down tube to the base tube), then the release line grows slack by about a foot or two. This requires the pilot to pull the line in a little to release in one easy pull.

Another disadvantage is that the system will not release automatically if the pilot falls through the control bar on takeoff. (In this case he will have to have the presence of mind to reach over with his other hand, grab the release line, take up the slack, and pull the release.)

And one final disadvantage with this design is that the pilot cannot release normally if he happens to forget to slip the release line over his hand before takeoff. THIS COULD BE VERY DANGEROUS, for then the pilot would have to (1) manually release both the front and the body releases one at a time, or (2) pull up the bridle by hand and activate the apex release by hand, or (3) somehow get hold of the release line in order to pull it, or (4) radio the driver to stop. The last option is best (followed immediately by the first), but none are good.

RELEASE LINE

The release line (about 8 ft long) is used to pull the release pin out of the 3-ring release (located at the apex of the bridle). The bottom end of the release line stays attached to the apex after the pin is pulled so that it does not flop around in flight and so that it can be dropped with the bridle if the pilot chooses to do so. It also allows the pilot to slip the release line off his hand once he is in free flight (even if he chooses not to drop the bridle).

APEX RELEASE

The main release for the bridle is the 3-ring release located at the apex. A single release is used because it is simpler and more reliable than using two or three. (No auto-release devices are used for a normal release although one is used as a back-up in case other components fail.) The apex is used because it is below any point of possible entanglement even in a lockout situation.

The 3-ring release was chosen for its proven record of safety and reliability. However, some problems associated with 3-ring releases have been discovered: (1) salt-water and sand can corrode the rings reducing their ability to slide through one another, (2) bent rings (it has happened) can bind on one another and fail to release, and (3) the release line can get wrapped around the release pin and fail to pull it out. Since these and other unknown problems can prevent even the reliable 3-ring from releasing, the bridle is designed to be manually released as described above (i.e. by radioing the driver to stop and then releasing the front release, the hand loop, and the body ring).

WEAK LINK

I still use #18 nylon line as my weak link, but no longer seperate it from the bridle with a leader. I now locate the weak link between the towline and the large ring of the apex release. By using a non-stretch bridle, there is no flyback problem when the weak link breaks. In fact, the only differences between a weak link break and a normal release are (1) the amount of tension in the towline and (2) the fact that the large ring stays with the bridle when the weak link breaks instead of falling away as in a normal release. Because there is a slight possibility that the large ring will be lost (if both the weak link breaks and the apex release releases), I keep a few large rings hand as back-ups.

FEEDBACK

This pretty well describes my current skyting bridle. If you have any comments or suggestions for further improvement please let me know - especially if you decide to use this design yourself and encounter any problems.
+
Fig. 1. Hewett's Bridle Configuration

Keel Ring
Extension Line
5 ft
Front Release
15 ft
Apex Release
Weak Link
Release Line
Body Release
Body Ring
Hand Loop
*
*

[Tad Eareckson]

1985/06
*
SKYTING NO.38
JUN 1985
*
1985/06-01

REGION SEVEN QUALIFIERS

Dear Donnell,

Region Seven's qualifying meet for the Nationals was, for the first time ever, a Skyting tow meet. It was held on the flat lands south of Elk Mound, Wisconsin.

Blown out the first weekend, after one round, we met the following weekend of April 27-28. The task was a 29.75 mile triangle course. Seven miles north to Elk Mound turn point, eleven miles west to Menomonie turn point, and the eleven and three quarter miles back to the starting gate. Gerry Uchylit, ((Uchytil)) the meet director from Chippewa Falls, devised the task.

I thought the cross, head wind leg, between Elk Mound and Menomonie, would make the Menomonie turn point unattainable. Almost three hours after I crossed the starting gate, I rounded the second turn point at Menomonie. At that point I became a believer in Gerry's task. Unfortunately, I sank out after two and one third miles on the final leg of the triangle.

Just think of it! To pick out two separate goals, and not just down wind, and go there! Hang gliding has come a long way.

When the points were totaled for all the rounds, I (flying a Magic 166) had tied for first place with our Northern Sky Gliders Club president and Region Seven director, John Woiwode (flying a Comet). Larry Majchrzak (flying a Magic 166), a previous Region Seven champ, took third place. Gerry Uchylit (flying a Magic 177 VG) came in third. As of this date, all of the points for the other pilots have not been published.

Terry took 6th place (flying her Maxi IV 186). She just put an order in for a 155 VG Magic. I'm sure her air time will double with her new glider as mine did.

Oh yea! Here is something you can feel proud about along with me: So far in 1985 my XC flights are 5, 10, 35, 22, 15 and 16 miles. My highest Minnesota gain is 6000' AGL. The longest time up was the 22 1/3 mile Region Seven flight; three hours and ten minutes. These were all Skyting flights. You have made possible a lot of fun.

Thank you!

Bill Cummings
*
1985/06-02

SKYTING IS LIKE CAVE DIVING

(Ed: This letter is a continuation of the dialogue between Doug Gordon and myself concerning his article "The Skyting Challenge." See SKYTING #36, #37.)

Dear Donnell,

Thank you for responding to my article and letter. Although you were quite timely in your letter I'm afraid that I had let things go to the last minute and had sent it in for publication by the time I had your response. Luckily, our differences were relatively minor. Now that I have read your views and have a broader perspective I believe that you'll find our ideas running nearly parallel:

1. I agree that Skyting is going through growing pains that do not relate to its inherent character and that this is due largely to a lack of education and the wrong attitude toward safety which itself is due to lack of education. I also agree that Skyting can be safer than footlaunch in the sense that it is safer in crosswind and that a pilot can choose to abort a flight right after takeoff which, of course, cannot be done at a mountain launch.

It should be noted, however, that these specific instances do not in any way indicate that it is safer overall than footlaunch. The empirical data indicates that towing is much more dangerous (accident stats). This relates directly to what I spoke of as the human element. It does not relate to any Skyting design but rather the psychology of those persons using it.

For many hang glider pilots the motivation for flying is not just the joy of flight but also the reinforcement of feeling of masculinity. This game of one-up-manship, this kind of general attitude is the polar opposite of the attitude that should be taking place in a situation where there is a large number of factors which must all be done correctly and where the safety of a pilot depends on the consistent performance of safety factors by another pilot who is towing him.

This is what I meant in the article by beginning a tradition of safety at launch and a launch director being unconditionally the boss as he refers to his Skyting criteria list. To illustrate this concept, I'd like to relate Skyting to an adventure sport which I took up quite a few years ago in Florida. There are also areas in Texas where they do this:

In most of northern Florida and throughout the southern gulf coast states there is a white limestone aquifer within the first 100'-300' of earth. The major rivers of the South which flow to the Gulf all have tributaries which disappear into sinkholes which form underground rivers that flow south and bubble up as springs near the Gulf. This water is crystal clear with a 300' visibility.

People scuba dive into these springs with underwater lights and safety lines to the spring entrance. It is a specialty of Scuba just as Skyting is a specialty of hang gliding. In both specialties the number of factors are greatly increased which means that the number of consequences is increased exponentially. Attention to detail is mandatory. Extensive use of lists takes place.

Divers are conditioned to this process by their initial training: Plan your dive and dive your plan. Dive tables are worked before each dive unless the participants PLAN to stay inside the no-decompression limits. Where they will go, how deep, how long, the buddy system, are all worked out BEFORE the dive. Add to this the specialty of cave diving and its redundancy of systems such as dual regulators (breathing gear), compasses, 3 lights, safety lines and then the increased complexity of how to dive caves (about 100 safety rules).

For some reason, I have not seen a corresponding attention to lists in hang gliding as there are in all other forms of aviation. We just do a preflight check, look at the conditions from launch, hang check and go. The reason, in my opinion, that this system has worked is that the pilot is only responsible for himself in footlaunch. In Skyting, pilots depend upon each other and do so in systems of greater complexity.

In Scuba, divers are always on the buddy system and their role, as such, is increased in the cave diving specialty. The important point, of course, is that their behavior is conditioned from the start.

Other parallels between the two specialties offer interesting view points in terms of empirical data from both sports: Skyting has been in existence for four years; cave diving for more than twenty.

Years ago in Florida, when divers began drowning in caves, the authorities in conjunction with the local dive shops tried to outlaw it. Since there were many more places to dive than law enforcement officials, this effort proved ineffective. Fatalities were still occurring.

In the end the Professional Association of Diving Instructors (PADI) began certifying cave diving instructors, increased education across the spectrum by including a subchapter in all basic (open water) scuba books on the inherent danger of cave diving without preparation and, most importantly, began a tradition where the plan or intellectual activity before the dive is viewed as just as important as the dive itself.

In other words, the dive plan is given equal weight to the dive and all divers know it. You can see it whenever you watch a dive party standing around working dive tables, discussing who will lead off, where they will go, etc. This system has been in existence for over ten years now and since it was instituted the accident reports have declined dramatically. They have decreased almost to the point of being as safe per hour as open water diving. That's almost but not quite.

There are still foolish guys who strap on tanks trying to impress their girl friends, or frat boys who drink beer out at the springs and do the same thing (from Fla. St. or U. of Fla.) and every once in a while you read about it in the paper.

An interesting aspect of the C.D. program is that a certified diver can do ledge dives (a cave dive into a spring only so far as he can still see sunlight) without any cave diving certification so long as he is with a cave diving instructor (a parallel to our Hang 1 for Skyting). In this way there is enough elasticity in the rule to allow learning while maintaining adequate safety provisions. Since no one knows what innovations might occur in Skyting or single release point at pilot towing, it is impossible to predict if it will ever become as safe as footlaunch or perhaps as safe as footlaunch is now. One thing is certain: You don't stop persons in THIS democracy by telling them they "can't" do something. The entire weight of empirical sociological evidence indicates that Americans are going to do what they want to anyway.

The best course of action in this and a number of other problems, I might add, is to increase relevant information flows in a timely and cost effective fashion so individuals can make informed decisions.

At this writing and what is known now about Skyting systems, it is my opinion that land towing will follow a similar pattern of going down the curve of accidents as education is increased and Skyting instructors are certified as did cave diving ten years ago. Whether Skyting becomes as safe due to its increased control under the two instances already mentioned, or the increased complexity outweighs these factors, no one can know but I will be the first to hazard a guess that within 10 years Skyting will get close, but not quite catch, the safety of footlaunch (which will also improve). I say this because of the human factor. There is always going to be some nitwit who will arrogantly disregard safety in the complex environment of towing.

2. In terms of teaching first-day beginners to hang glide by Skyting, I enjoyed very much your analysis of tow training beginners. I believe that given all the time necessary it could have been done by giving human tows of a couple of feet of altitude or tethered with a turkey line to the noseplate or both. You have more experience at this than anyone else in the country. My Skyting students are all Hang 1+ from the top of my man-made trainer hill before beginning. On 3 occasions I did try to teach rank beginners on windless days (all athletes at Arizona State U.) but to no avail. While there were no injuries it became obvious that there would be if I tried it all the time with persons who could not adjust airspeed.

My real question is: Can it be done cost effectively, timely, from a business point of view and at a safety level above the 99th percentile? That is what I and, I am sure, the USHGA would like to know. It is my experience that it cannot, but then again you might be doing something that I'm not or visa versa. Perhaps our trainer gliders react differently or the body ring is attached higher or lower or some other extraneous variable(s). Next time you are out at the Skyting field you might consider doing a time study of a rank beginner. I'd certainly buy tickets to that data!

3. I agree that learning occurs with less fatigue in Skyting as one does not have to walk the glider up the hill and can instead roll it on training wheels. In terms of number of flights per hour, again you must know something I don't. My experience is a conservative 3/1 ratio of footlaunch/Skyting.

4. You were correct and I was wrong about Skyting in high winds. Actually I have always agreed with your belief in flying in moderate winds. Sometimes when one writes he states things in a way different than intended. What I meant to say was that students should Skyte in different winds of various velocities (other than high) before going to a higher altitude.

5. and 6. Pulling in/Flying fast/Towing past 45 degrees. Let me take this opportunity to respond to your question and to Tony and Rona Leicester (Skyting #33).

When I drew up these Skyting Safety Rules they were intended for students in a learning situation. I can afford to have students fly a bit faster under tow especially on Seagull Seahawk trainers which do not oscillate at faster speeds as straight leading edge gliders tend to do. I cannot afford to have students stall under any circumstances. The line to the keel is attached to the release 16 inches in front of the hang strap.

The answer, then is that you, Tony, and Rona are correct. There is nothing wrong with Skyting and pushing out under proper airspeed by an experienced pilot since skyting simulates gravity. But let me add something to that. First, the empirical evidence does indicate that more accidents occur in hang gliding each year because of stalls than all other reasons combined. Secondly, since Skyting is still in its infancy, is it not better that we stay on the conservative side of the equation, especially, considering the accidents which already have occured? I'm not promoting a pull-in-to-the knees rule but rather a 2"-past-best-glide while under tow rule. After one releases then he should feel it's fine to play.

7. I agree that the danger of staying on line is greater than the danger of entanglement in an apex or threaded system.

Thank you for responding to my article. I look forward to working with you in the future to develop Skyting safer year by year.

Douglas J. Gordon
Tempte, AZ

((Tempe))
*
1985/06-03

REPORT FROM ENGLAND

Dear Donnell,

It has been some time since I last wrote. I do hope you are still receiving lots of news and that your family is in good health.

In England faint glimmers of summer weather are apparent, so we look forward to some interesting flying.

At the end of March we had our first cross country of the year. Edmund Potter managed 6 1/2 miles in a down-wind thermal.

The day was fine with small clouds forming. The wind was 15 mph at ground level from the South West. It promised to increase later and became rather gusty; so the chosen moment to fly was important.

Edmund was flying a UP Comet. The tow up looked quite turbulent with lift and sink patches. The main climb was vertical with a little backward movement. The car had driven about 500 yards before stopping. From then on Edmond skyted up to 1400 ft. The drum was still paying out fast when the car was stationary.

Edmond was waiting for a particularly juicy cloud to come over when a gust hit him and broke the 210-lb weak link. The aircraft quickly recovered and several seconds later Edmond circled away, climbing to 2000 ft. Unfortunately, there is a military heliport about 7 miles downwind; so, not wishing to land in controlled airspace, Edmond decided to leave the thermal and try to cross to the next. Sadly, landing came first. The wind had strengthened, which made landing out a little dangerous, but all was well.

Last Saturday we had 2 more cross countrys. Phil flying a Cutlass did 1 1/2 miles and Rona on the Clubman did 3 1/2 miles. This was the first bubble break for them both.

TWO UP

Yes, we've actually got round to doing it. I borrowed a large Stubby, which is a training kite commonly used in England to try out some dual towing. The Stubby is regularly flown dual from the hill. With its large slow-flying characteristics it's most suitable. I connected the towing leg so that the glider would fly completely hands off from start to finish.

Rona and I spent some time hanging together and getting comfortable. We then had a few man tows, then onto the car. The kite was supported on my shoulders when the tow began. The kite rose, lifting Rona first. I ran a few more steps. Then we were both airborne.

The condition of the day was light to nil wind. We tried 3 more flights, each time getting a little higher and finding no problems with the landings. During the day I made 12 flights in all with persons with no flying ability. I and they found it very pleasant. I will add the restrictions I put on persons I flew with were:

A. They were smaller than myself.

B. That on no account were they to touch the control frame.

The co-pilot put one arm around my shoulder and held my wrist with the other hand. Rona tried climbing up on my back, which was quite comfortable for the climb up.

We feel that dual towing is pretty safe, providing you have a stable aircraft and that the pilot in charge has had at least 150 towed flights with a P2 rating.

TOWING WITH BEGINNERS

This is beginning to take effect in Britain. We are gearing up for abinitio training. Courses are being structured to handle students learning on the tow line and wishing to convert to the hill and vice versa.

We already do a course for experienced hill pilots to convert to the towline. This is a basic course but very effective.

We have just put together a task sheet for P1 & P2 pilots. I will send you a copy once it has been approved.

GERMAN TRIP

The tow system in Germany appears to be chest towing with a "V" line connected under and over the bar. The initial climb is towed over the bar with the "V" line under, slack. At a safe height, the first overline is released. A jerk is felt as the under "V" line takes up the tension. This system gives quite a nose-up quality that has become accepted as the norm in Germany. It is possible to release both over and under "V" lines together in an emergency.

The towing power is provided by a power static whereby the towing tension can monitored. The winches use a 1.8 mm wire and are fitted with fast-acting guillotines.

Find enclosed a copy of the report from the BHGA training officer. He recently went to Germany to check out a couple of their systems.

That's all for now.

Tony & Rona Webb
Norfolk, England

One further note: Donnell, could you send me names of insurance companies that look favorably upon aviation? We need access to outside insurance if the situation arises where politics interfers with towing development.

(Ed: I don't know any insurance companies that might provide towing insurance. Do any of you readers know any?)

We have now two persons elected to our counsel: myself and Graham Geary, both heavily committed to towing, officially recognized as skyting. Many thanks for your continued efforts.
*
1985/06-04

LET'S KISS THE BRIDLE

Dear Donnell,

I hate to criticize your excellent work, but after reading about your latest bridle, I feel I must say something. Your new bridle appears too complicated.

The "Donnell Hewett" bridle or tow bridle, as originally designed, is a safe, effective and SIMPLE (i.e. uncomplicated) piece of gear. There have been all types of modifications tried, but usually people have come back to the original system with a single RELIABLE RELEASE at the leading apex. (Out here we use a "panic snap"--same as your horse bridle release--whereas you people seem to prefer the 3-ring release.) The release rope is usually attached to the centre of the base bar so that, if the glider starts to nose in, the release will be triggered. It is also close at hand for any emergency release. All hardware (rings, shackles, etc.) which is NOT ABSOLUTELY NECESSARY is removed from the bridle and the attachment ropes. This leaves only:

a) the "panic snap" release at the apex--it has a ring at the pilot's end for rope conection (clove hitch, etc.) and for the bridle rope to slide through and

b) a small shackle at the harness ties (could use a ring, but a shackle can be undone more easily.

Keel rope to top bridle rope connection is by 2 bowlines.

After release, the bridle is just let drag, and the top bridle rope is thrown around the bolts on one side of the A-frame base bar. This is used whether the pilot lands immediately for another tow or whether he flies 100 miles.

Unless there is to be a marked increase in SAFETY and EFFECTIVENESS, let's KISS. (Keep It Simple, Stupid!)

On the brighter side, I hear you people are to have a competition at Hobbs, New Mexico. From my reading of some sailplane stories, I don't think the organizers could have picked a better spot for a tow comp. I look forward to hearing the results.

Out here there will be two major tow comps. this coming summer. The NSW State Championships (late November) and the 2nd Flatlands Challenge (Dec./Jan.) will be held at Parkes. I will be making a bid for the Jan. 1987 Australian Nationals to be held at Parkes also. An international Flatlands probably will be held in 1988 in conjunction with the 1987 World Hang Gliding Championships (late Dec. 1987 - Jan. 1988 in Australia).

Also, it's to be noted that Rick Duncan (one of the World Team members) flew 291.7 km (about 182 miles) in central N.S.W (near Parkes) last summer from a tow launch.

Denis Cummings
Dights Crossing
Singleton, N.S.W.
Australia
*
1985/06-05

FLATLANDS DIARY
PART 1

by The Pink One

(Ed: This is the first of two parts reprinted from the SKYSAILOR, the official publication of the Hang Gliding Federation of Australia.)

On the 22nd of December 1984 a couple of dozen pilots had gathered to Ted Tomlinson's property between Parkes and Forbes in central NSW for the inaugural Flatlands X-Country Challenge. The first 4 days were to be practice days and that was because quite a number of pilots had not towed before; then the comp. proper was to start on 27th Dec. There were 5 N-S (with about 50m between each strip) very close to 1 mile long. So the props were there, the stage was being set and after an extensive seminar on towing techniques, bridles and releases from Denis Cummings, the pilots moved out to the N end of the tow strips to begin putting Denis' theory into practice.

On the strip, wind was light and variable SW/S but SW above 5000' AGL. Those pilots with previous tow experience towed up early afternoon. Carl Braden got away on his 2nd attempt for 59 km and 8600' a. t. o. Chris MacDonald crossed over the Herveys Ranges for 66 km. Flash ? got the best distance of the day of 82 km reaching 7000' a.t.o. to fly due North to land past Tomingley.

5-6 pilots had their first tows today at about 5-6 pm on mellow air, all takeoffs very good with only one minor nose-in all day due to wings not being level on takeoff.

The weather stayed blue all day apart from some cirrus coming across from the SW. Many pilots from the coast saw dust devils for the first time of which there were plenty as the day progressed but which died out as the heat left the day.

Bruce ?, after a best distance of only 10 km at the coast, performed extremely well with failing vario batteries to fly to Yeovil for 75 km and Bruce Reeve was the last to get away at 4 pm and covered 40 km to land at the foot of the Herveys Ranges.

More surprise and some amazement was expressed by lots of pilots on the frequency and strength of dust devils, 2 gliders, in fact, being tipped over due to the proximity of these dust and dry grass beasties, resulting in more conservative set up procedures.

24th December

A blue morning with a N wind which picked up to 10-15 mph by 10 am. Dust devils were on the prowl so after a seminar on cloud and thermal streets by "Nostradenis," only pilots with tow experience set up this morning with Denis estimating roughly 10,000' ASL cloud bases. The S end of the strip was used in the morning and funny things happen out here as we're beginning to understand. Mid to late morning the N wind eased back and Denis Cummings towed up and drifted off in an E/ESE direction and Garry Morgan the NE. The other pilots had to wait for the winds to swing back for the SW to come in from the NW/W seeing as we were all at the S end of the strip but that wasn't to happen.

Bent uprights were seen on a couple of gliders, because of tailwind landings in the variable wind conditions. One pilot severly nosed in around mid afternoon generally bringing the day to a close even though it was a picture perfect day.

Denis dribbled out only 9-10 km distance and never got above 4200' AGL and Garry Morgan, a PR3 with some sailplane experience, scored a 110 km run to Wellington (a popular route in the prevailing upper level SW winds and cloud base at 13,6000' AGL/14,400' ASL) but failed to dress sufficiently and kept to about 9000-10,000' AGL after he had got his best height.

25 December

Howling 30-35 mph N-NW winds obviously blown out, temperature 39C before a cool SW change that evening.

26th December

A cool blue SW morning 5-10 mph which increased to 15 mph during the day, a wind gradient exceeding 200' a.t.o. Rog Glen, chief instructor at Forbes airfield, gave a relevant seminar on light aircraft operations and described their takeoff and landing procedures.

Today, more tow vehicles were used to cater for the extra pilots that had turned up in the previous 2 days. So, more pilots got plenty of tows, which was good. Two pilots managed to lob over the back for 6-8 km distance, conditions being rather stong and headwindy above 200' making for choppy, hard to work thermals.

A pilot briefing was held this evening on the eve of the competition. Towing procedures were explained once again as were explanations for the contest rules and scoring.

27 December - 1st Comp. Day

A pilot briefing on the task, a 100 km run to Albert, NNW of Tichborne. Pilots were given their number, Denis gave his forecasts and then it was out to the field. CU's were up about 9:30 am, the earliest we've seen them up to date. The gate for the "window" opened at 11 am with pilots starting to get away after 11:30 am. The day progressively blued up over launch and along the way to Albert. Three pilots made the task with the rest scattered along the road. The average distance covered was approx. 30-35 km. Heights of between 6200' and 7400' AGL were mentioned, better heights obtained later in the flights.

28th December - 2nd Comp. Day

Gale force SW-SE winds forecast for Sydney and surrounding coastal waters. What we got this morning was SE winds 5/8 mph which picked up to a gusty 20 mph and tending a little more to the S. CU's started about 8:30 am and Nostradenis expected base to rise to 7000' at about 7 pm. A task was called by John "Charlie" Clarke, the "meet head," to Tomingley about 75-80 km to the N. First pilot got away at 2 pm as the wind picked up to a gusty 15-20 mph, but pilots were becoming more confident about their takeoffs now and were getting up and away nonetheless.

By the end of the day, only Ian Cummings had covered the distance to Tomingley and, rather curiously, continued on into Narromine for a distance of 110 km, 30 odd km past the goal where, so the story goes, he was given permission to land at the glider strip at Narromine, and was urged to land quickly from 7000-8000' ASL so that a not very impressed comp. official could give him a lift back.

So, today's score:

1st Ian Cummings
2nd Bruce Reeve
3rd Trevor Gardner
4th Carl Braden
5th William White
6th Trevor Gardner

And placings after the 2nd day:

1st Ian Cummings
2nd Garry Morgan
3rd Bruce Reeves

Clive Farquahar, a non-comp. pilot, flew 125 km this day to Tottenham in a more downward direction, test flying a Sabre 155.

29th Decenber - 3rd Comp. Day

Cloud base started real low, wind was from the SE at 5-10 mph. It wasn't long before the wind strength turned to 15-25 mph. CU's were drifting SE-E and the task was called: a goal to Trundle then open distance to the NW to Nyngan and beyond. Another open window launch. Only one pilot, Ross Duncan, got up in slightly calmer conditions than those that were prevailing for the day, that is, gusting 15-25 mph. He launched at 3:30 pm and did 60 km to Fifield.

Conditions had deteriorated by then, the winds gusting and the direction chopping about from the E-S, so Ross did well to get away. There was about 30-40 mins when pilots could have gotten away but weren't set up as conditions were suspect. Only one other pilot apart from Ross had bothered to set up but was unable to launch because of the awkward conditions. Cu Nims and storm cells from mid afternoon basically dissuaded other pilots from setting up.

There was some argument about the validity of the round as only one pilot even towed up, but it was decided Ross's points should stand. But next time, in marginal conditions, a percentage of pilots would have to tow up before the task became valid.

30th December - 4th Comp. Day

Stratus cloud from the SE-SSE moving in this morning, probably from the strong, very unstable winds that were happening around Sydney and environs. Wind stayed light most of the day until a storm cell came through and straightened and strengthened the winds from the E and variable to the SSE at up to 20 mph. Good unstabe CU's over the tow strip generally but they degenerated as more moisture fed in and the CU's became more unstable to the point of squalling. Ian and Denis Cummings picked it well and launched into a small storm cell and dabbled over the back, the only two comp. pilots to get away. After that storm cell had passed, the air became horribly stable and all that was left was to be towed up and fly back to a landing before giving the day away because of the very stable air. One pilot stayed set up after everyone had gone and towed up into the biggest storm cell of the day hoping for some frontal left, but couldn't find any so bailed out and landed in a 20 mph SSE and rain, just hovering down to land.

31st December - 5th Comp. Day

Denis gave a seminar on the many types of instruments available, discussing the advantages and disadvantages of each type that was displayed there today. Denis would have won a prize, if one was going, for having an instrument panel with the most gadets on it and the most tricks associated with it.

CU's started forming about 9-9:30 am, winds light and variable but mainly from the SE. It was some time further into the morning before CU's began forming over the air strip and by mid afternoon, though there were still CU's about, the atmosphere was showing signs of wanting to stabilize and "blue up." Wind on the ground swung back toward the S but drift up top was SE-ESE.

The task called was a 90 km out and return to Trundle and only part way back due to the freshening SE-ESE. Val Wallington mad a good showing to just short of Trundle. The bulk of the pilots who got away experienced only 1-2 thermals and that was that, with early outstandings being the order of the day. So the daily scored was:

1st Denis Cummings
2nd Alan Tolley
3rd Val Wallington
4th Nigel Felton
5th John Ritchie
6th Carl Braden

...continued next month...
*
WHO SHOULD TOW?
*
1985/06-06

Dear Donnell,

I can't believe it! I've been wanting to get into towing for a long time. Now I'm finally ordering a skyting system and our club has a winch and we're all set to go.

I would appreciate some guide lines, if you could help, about who should fly the tow with respect to hours. We have a lot of pilots in our club who are really good guys but they have a severe case of intermediate syndrome and I'm a little worried they are going to want to jump right on the tow a little too quickly. So if you could help me out by suggesting a minimum number of hours in the log book before you fly the tow, it might make things easier to control. Maybe I'm worrying too much about this. I've heard of people learning to fly by towing (and certainly some of my first high flights in 1976 were on a 16' standard behind a boat) but I think a good safe launch from a mountain is still safer. I admit to a lot of ignorance about towing.

I believe we have enough level heads in our club that we'll do just fine. Thanks for your help and I'll be calling you to let you know how things work out or if we have any problems.

Peter Luke
Victoria, B.C.
CANADA
*
1985/06-07

Dear Peter,

I share your concern about eager pilots who finally get all the equipment they need to tow and go out and start towing. I am not so concerned about the amount of free flight experience a pilot has as with his caution toward towing. (Some skyters with more experience than I feel that an Intermediate, Hang III, rating is needed to start skyting.) I personally have seen pilots everywhere from Hang 0 to Hang 5 learn to skyte safely - but the method of training is obviously dependent upon the experience of each.

If you want to insure safety during the initial stages of your training program, I would suggest your training program, I would suggest that you adopt the following hard and fast rules:

1. Until you have pilots with at least 50 towing flights on the skyting system who can provide experienced towing instruction, let only Intermediate (Hang III) or better fly. In other words, until you have pilots qualified to instruct towing for Beginners and Novices, they should stay off the towline. (While they are waiting to fly, they should help operate the system and learn safely to perform the duties of every ground crew member.)

2. No one should be permitted to fly until AFTER he/she has read every back issue of the SKYTING Newsletter. There are numerous important safety points scattered throughout these issues which cannot be learned by simply scanning the material. Without this background of material, it is too easy to make a few good flights and mistakenly get the impression that one knows enough to tow safely. HERE IS WHERE THE REAL DANGER LIES - PILOTS BECOMING OVER CONFIDENT BOTH IN THE SYSTEM AND IN THEIR OWN KNOWLEDGE.

3. Everyone who tows (or even who helps operate the system) must realize that skyting is STILL EXPERIMENTAL AND EVOLVING. Therefore, they must not only exercise the caution of appropriate to learning a form of aviation that is new to them, but must also exercise the caution appropriate to practicing a form of flying that is new to everybody. PATIENCE and CAUTION are essential, RUSHING THINGS and OVER CONFIDENCE can be FATAL.

Donnell Hewett
*
1985/06-08

QUICK-RELEASE HITCH

Dear Donnell,

This is a quick-release hitch I designed and have been using with winch towing. I am using 1" dia. by 1/8" welded steel rings available in any hardware store for $0.35 and the skyting bridle you designed with manual keel and auto stomach. I have an idea that the keel release could be pulled by a cord going through a hole in the top of the helmet easier than trying to free up a hand while in a critical situation. It would require flying on the downtubes until release at which time going prone would automatically release you.

I made two sample hitches so you could pull one and still see how it was tied. I have tested it to 500 lbs and the pin pulled with 3 lbs pressure.
+
SPRING RELEASE PIN
+
KEEL
RELEASE PIN
3/16" LINE WITH KNOT INSIDE HELMET
1/4" HOLE
MANUAL RELEASE LINE THROUGH HELMET
+
Leave enough slack to fly but tight enough so it will release with a snap of the head, not hooked in, falling etc. I haven't tried it yet but will soon.

I also build power winches for sale and will send pictures soon.

Thanks for all your hard work.

Jim Carlille

((Carlisle))

P.S. I'm using a 3/16" spring pin to release. I've also used bobby pins to release.
*
1985/06-09

CONGRATULATIONS ON RECEIVING THE ED GUARDIA TROPHY

Dear Donnell,

Congratulations on your award! The entire Board was extremely sincere about granting you the award for the years of excellent work you've done in towing.

The Publication Committee also agreed with you that a monthly towing column would be present in the magazine. Gil is going to use you, Dean Batman, and Jean Michelle, ((Jean-Michel)) not only to help write for the column, but to review and comment on articles submitted by others.

Again, congratulations on the USHGA's highest award.

Douglas H. Hildreth, Chairman
Accident Review Committee
USHGA
*
1985/06-10

Dear Donnell,

Congrats on your much deserved award from USHGA.

Haven't done any towing since moving to Georgia, but lots more mountain flying. Come join us some time in Chattanoga.

C U at cloudbase.

Cal Tax
Marietta, GA
*
1985/06-11

(Ed: Let me take this opportunity to thank all of you who have recently sent me these and other expressions of gratitude and congratulations. It really feels good to be appreciated. Therefore, let us not forget to express our appreciation to the many other groups and individuals who have also contributed to the improvement of towing. One group of individuals I particularly appreciate is you, the subscribers to this Newsletter. Without your support, contributions, and encouragement I could have accomplished little or nothing.)
*
1985/06-12

PERSONAL THANKS

Dear Donnell,

I have had one day of skyting with some fellow pilots from Iowa City and Cedar Rapids, but now that spring has sprung we well be out in force on the weekends.

This note is just to personally thank you for your contribution to hang gliding for us in the flat lands. I have towed with the old Yarnell system and have experienced fright! Now I have tried the skyting system and can experience flight! Even in Iowa!

Keep up the good work, and thanks again.

Jim Hale
West Liberty, IA
*
QUESTIONS AND ANSWERS ABOUT BRIDLES AND RELEASES
*
1985/06-13

Dear Donnell,

I am a hang glide pilot with about 200 boat tows. These were all using a conventional tow bar. I have recently used your center of mass system and found that it worked quite well. There was a question as to where the upper bridle was to be attached: 16 inches in front of the heart bolt or at the heart bolt. With the attachment point at the pilot's head is in the way of the upper line. I would appreciate any information you have on this or any other aspect of your system.

Enclosed is a knot used as a release. We use 1/8" or 1/4" nylon line. It seems to work well under the 130 pounds tension provided by Jim Carlisle's stationary winch. I would be interested in your opinion of it. I think it is important that the pin is an eye bolt so that it does not slip through the knot.

When the pilot pulls the upper release, the bridle slides through the rings and increases the distance between the two bottom rings. This pulls the bottom eye bolt automatically. This will work with the automatic release on the top, but in case of automatic release malfunction I think it works best with the automatic release within easy reach.

The only real problem I can foresee would be getting the upper bridle line caught in the front flying wires. When the top pin is pulled that line snaps right out. In a lock out situation where the bridle was pressing against the flying wire, release might cause it to wrap around the wire.

It is also important that there are no twists in the bridle and that the release knot is tight enough so that the eye bolt doesn't slip out.

If there is any fee involved with your information let me know. Again, I am interested in your opinion.

Ted Hocking
Holyoke, Mass.
*
1985/06-14

Dear Ted,

Thanks for expressing an interest in skyting. Here are the answers to your questions:

1. Theoretically, the keel line should be attached as close as possible to the "center-of-mass of the glider" - which usually means at or near the heart bolt. However, as you pointed out, this can interfere with the pilot's head movements, so many pilots move the attachment point forward enough to clear the pilot's head - namely, about 16 inches. Another advantage (or disadvantage if you prefer) in doing this is that the towline pulls down on the nose of the glider at high tow angles making it easier to release without danger of stalling (also harder to climb to maximum altitude). I recommend that you try it both ways and choose the one that suits you and your glider.

2. Enclosed you will find information about obtaining back and future issues of the SKYTING Newsletter.

3. The knot you sent me is similar to that devised by other pilots and described in back issues of SKYTING. The main problem with such knots is that under certain conditions, they do not release when needed. Generally, what happens is that the release pin gets turned so that the pull is not straight sideways, the tension on the line is high, and the knot becomes tight. Then the pin will not pull out and the knot will not release. Since it only takes ONE such failure to produce catastrophic results, I do not recommend using such knots.

This is especially true since reliable 3-ring releases can be purchased for about $25.00 and home made for about $5.00. Other reliable releases for threaded bridles can be purchased for about $50.00. To me it seems like false economy to experiment with your own knots. Personally, I use a 3-ring release on my system - it has the best reputation and a long established safety record.

If you really want to use your own knot, I would suggest trying the one illustrated below. Unlike your knot, the pull pin cannot bind up on you. I believe it to be quite safe if tied correctly, but more skill is required to tie it than to fasten other releases. If tied incorrectly, it may release prematurely or - if really mistied - fail to release at all.

4. In my opinion, 1/8" line is too small to be used for a bridle, 1/4" line is marginally acceptable, and 3/8" is better. The reasons are that the smaller lines have more stretch and more flexibility. Therefore, they are more likely to fly back into the pilot's face and/or become tangled with the pilot/glider system.

5. Auto-release lines are no longer recommended. Several pilots have been hurt because of their malfunction in one manner or another. Back issues of SKYTING describe the many ways things can go wrong. If one release fails after releasing the other, the glider can pitch or tuck into an inverted position which usually results in structural failure of the glider. Instead of the bridle system you illustrated, I would recommend the "threaded bridle" which eliminates the auto-release line. (Of course, the threaded bridle must be constructed properly, or it too will be dangerous.)

6. Yes, there is a possibility of the keel line tangling with the glider. But with a threaded bridle this is improbable (and so far unreported). However, some pilots reduce the probability even further by placing the keel release below the flying wires (at the end of an extension line which stays with the glider after release).

Other pilots completely eliminate the entanglement problem (as well as the double release problems) by using a single point release at the apex of the bridle. Of course, the bridle then stays with the glider, but that is a small price to pay for the increased safety aspects.

7. If you are serious about skyting, you should read ALL of the back issues of the SKYTING Newsletter carefully to be sure that you understand the potential dangers and problems you will be facing. It is foolish to re-discover for yourself the mistakes others have already made. If you do not have access to these copies from your friends, then get your own copies. One accident can easily cost you more than the price of all the back issues plus a subscription for future issues.

Let me know if I can be of further service.

Donnell Hewett
*
*

[Tad Eareckson]

1985/07
*
SKYTING NO.39
JUL 1985
*
1985/07-01

SOUTH AUSTRALIA EASTER
1985 FLY-IN

by Dave "Daring"
South Australia

(Ed. This article is reprinted from SKYSAILOR, the official publication of the Hang Gliding Federation of Australia.)

Friday

In starting this brief account, let me say "three cheers for the Donnell Hewett towing system" as this certainly saved the weekend!

Very early on Friday morning I was woken by the rolls of thunder descending on Adelaide and the blinding flash of lightning. Soon it started raining and by 5:00 AM I thought that it was going to be another one of those useless weekends. By 7:00 AM we were away and most of the storms had cleared. Driving along Highway One toward Locheil, I was very impressed by the huge clouds and thought that if the wind was right, then we would have a good day.

Arriving at the Snowtown Caravan Park we found a few people had already arrived and were setting up camp. By this time, a nice southerly was blowing so we all headed out to Barn Hill, a beautiful 500' bowl, 20 km from Snowtown. Approaching it, we sighted Steve B flying his Magic III getting good height. After driving to takeoff - about 15 gliders had arrived - I set up and took off, straight into a 500 fpm thermal. It did not look good to go X-C as about 20 km behind launch were several large rain showers, so I stayed around the area for a total flight time of 4 1/2 hours.

Throughout this time, many more pilots were flying and having varying degrees of success, with approx. 4-5 learners having fun on the lower slopes. One of our new female pilots, Stephanie, flying her new Mars, was doing quite well. Late in the afternoon, the "Magic Hour" came on and many pilots flew to sunset in perfect smooth conditions!

Saturday

Due to a large high pressure system moving through, the conditions were to prove light and variable all day. Mark, Danny, Scott and I drove a few km to the east of Snowtown looking for a paddock to tow from. We eventually found a road but heard Phil Flentje radio through that he had a 2 km long flat paddock near Kodinga, about 20 km farther north. The kind farmer was very pleased to let us use it and soon there were about 22 gliders and 4 tow lines set up. We organized different CB frequencies for each line and proceeded to tow up.

My first tow saw me tow through a thermal and release and within minutes I and my new Magic III were up above the paddock. Steve B., George Kambas, Peter Seleski and Phil were all circling in a nice thermal over Koolunga township. It was one of those days with no drift at any altitude and you could fly from thermal to thermal, covering about 5-6 km each time. Farmers were ploughing their paddocks, triggering off thermals and this was also useful, besides the brown paddocks. I landed after 2 1/4 hours and had a bit of lunch. Afterward I talked to a few people. All seemed to be having a great day, with no hassles with tow lines tangling.

At about 4:15, I took off again and maintained in weak thermals for another hour. The interesting thing about this day was that before the tow system, we would have had a very frustrating day on top of a ridge. Many of the PR 2's had excellent tow flights and I feel that this is the way hang gliding intermediate training may head.

That night, we drove into Pt. Pirie and "hit" the town.

Sunday

The next day started out foggy and a forecast high of 32 degree C with light northerly winds. By 9:00 AM the sky was clear and warm and several of us were having breakfast at the roadhouse near Snowtown. Looking out the window, I noticed that we were right next to a 2 km long paddock. After inquiring the whereabouts of the owner, he gladly let us use it, so about 12 of us set up our gliders and two lines. The rest of the flyers went back to Koolunga. By the time we were ready to launch, perfect CU's were forming overhead, base about 45 km away, near Lare, after a leisurely X-C taking in the scenery!

Keep an eye out for Julius Mack as he is showing tremendous X-C potential.

Gary Fimeri launched some time, climbing out to be a speck in the sky. I think he landed about 80 odd km away, near Porters Lagoon, by Burra. Once again the winds were only about 2-3 knots (not good for our low 600' ridges).

Andy Watson and I launched and spent a very enjoyable couple of hours thermalling around the area. Mark, flying his new Moyes GTR, had his best thermal flight ever, and he was stoked! Meanwhile, the others had launched from Koolunga and were circling around, waiting for the rest of the group to get up. Soon, everybody was up and they flew more or less together to a point on the Burra-Morgan road. Their distance was about 90 km and once farther inland, the cloudbase climbed to about 8000'. So ended another incredible towing day and everybody celebrated in the Locheil Pub.

Monday

Same weather pattern today, but a little bit warmer. This time everybody set up at the Snowtown paddock and with nearly 20 gliders it was crowded.

Phil Flentje was first up today and he immediately climbed, circling toward Illawarra Hill which was about 10 km to the NW. Paul (Nosepick) Clelland caught an excellent thermal after release and spent a very enjoyable hour or so thermalling in the area with his new Magic. I clocked up another 1 1/2 hours today circling around with George Kambas in his GTR.

Gary (Emu) Fimeri and Steve Blenkinsop flew to Pt. Boughton on the coast (about 40 km). They landed on the beach and enjoyed the beautiful sunset while sipping on icy cold beers.

Later that night we quietly raged on in the Locheil Pub and then drove the 1 1/2 hours back to Adelaide.

In closing, the weekend would probably have been a disaster if it had not been for the towing systems. I agree with my old mate, Denis Cummings, and feel the time is very near when we will have a major hang gliding X-C, aerobatic competition from the flatlands. I would like to see this held from a major sailplane club, where we have spectators (i.e., sponsorship) and comfort facilities.

Safe soaring all!
*
1985/07-02

IMPROVING TOWING SAFETY

by Denis Cummings

(Some suggested Tasks and Theory Questions for a VEHICLE TOW LAUNCH ENDORSEMENT for consideration in the HGFA--Hang Gliding Federation of Australia--towing program.)

The endorsement, which will be made in the pilot's log book, etc., is intended to assist the safe and standardized introduction of vehicle tow launching.

The "Skyting" system was designed to allow pilots to launch and fly hang gliders from their 1st day through to Advanced, in locations that lack suitable training hills. This is only safe if a GRADUAL ADVANCEMENT method is used and the instructor has a full appreciation of the requirements of this teaching methods.

Wherever possible, it is strongly recommended that pilots should attempt all BEGINNER rating tasks from suitable training slopes, and that pilots should have completed all tasks and questions for their BEGINNER RATING prior to attempting the VEHICLE TOW LAUNCH TASKS.

THEORY: (scores in parenethesis)

1. Describe the operation of the "Skyting" bridle. (3)

2. Why must you use a weak link? At what load should it break? (3)

3. Why do you use a (short) leader? Discuss length and diameter. (3)

4. Why must there be stretch in tow rope? About how much is needed? What types and size(s) of rope can be used? (6)

5. Describe the additional loads on a glider while under tow. (3)

6. List the basic Skyting Criteria. Describe how each is controlled in practice. (12)

7. Describe the steps to be taken in the event of release malfunction on (a) a nil wind day, and (b) a windy day. (3)

8. Describe the steps to be taken when a weak link breaks. (3)

9. What are the signals between driver and pilot (a) before launch? (b) during launch? (c) before and after release? and (d) during a release malfunction? (6)

10. When should you release while under tow? Describe the situations, the reasons and the signals to the driver. (3)

11. Describe the precautions to be taken when towing in cross wind: (a) at launch, (b) during climb, and c) at release (3)

12. Describe the effects of too much pilot imput while under tow. (3)

13. At what speed should you fly while under tow? What happens if you fly too slowly? too fast? (3)

14. Describe tow driving procedures with reference to tow-rope tension, signals and rope handling. (6)

15. Discuss the effect of a noticeable wind gradient on (a) the pilot under tow, (b) the tow car. (3)

A pass requires 54 marks out of 63 possible.

PRACTICAL:

1. Pilot correctly sets up tow bridle and attachment points to glider, and carries out all pre-flight, pre-tow checks.

2. Pilot demonstrates correct launch/flight attitude and handling. Knows all signals.

3. Pilot demonstrates a take off and short climb, followed by a release (after slackening of tow tension) and landing, all into the wind.

4. Pilot achieves a pass score in the theory examination and, in the opinion of the instructor/safety officer, is ready to attempt a high tow.

5. Pilot completes 10 high tows (greater than 500') with correct signals, release and return flight procedure.

6. Pilot experiences 1 weak link breakage and follows correct flight/landing/signals procedure.

7. Pilot completes 5 head-crosswind (about 45 degrees) high tows.

8. Pilot completes 5 nil wind high tows.

9. Pilot satisfactorily drives tow vehicle and demonstrates correct (a) tension control, (b) signal usage and recognition, and (c) rope handling.

10. Pilot demonstrates ability to tie/check/set up (a) weak links, (b) tow rope, and (c) tension guage/meter.

11. Pilot demonstrates a safety-conscious attitude toward tow launch activities.
*
1985/07-03

FLATLANDS DIARY
Part 2

by Bruce Reeve

(Ed: This is the second of two parts reprinted from SKYSAILOR, the official publication of the Hang Gliding Federation of Australia.)

1st Jan 1985 - Open Day

After some obviously very good public relations work by Denis Cummings and other officials and some excellent response by the local TV and newspapers, approx. 300 or so tourists turned up to watch an incident-free day of towing. Bob Silver and "Charlie" Clarke had their trikes set up and around mid afternoon someone flew in a Thruster ultralight and did a few loops for us.

Ross Duncan got away today for the best fly of the day of 104 km and reached 7600' AGL. A few other pilots got up but couldn't stay up and covered 18-20 km.

Other pilots were mingling with and enlightening the tourists who, on the main, asked sensible questions, which was a great relief to a few of the pilots who had had a New Year's Eve dinner at the Parkes RSL, then partied on to the Leagues Club to see the New Year in.

2nd January - 6th Comp. Day

"Charlie" Clarke, after doing a temperature trace in his trike, as he had done every day, climbing up to 10,000' ASL, called an open distance task to Bathurst, but as it happened with the day, the task was changed while the pilots were in the air as the wind direction had virtually cancelled out Bathurst as a goal and instead it was just a straight open distance to anywhere and beyond.

The weather started this morning with a light S breeze which swung to the N-NW at about 8:30 AM. CU's formed below some middle level strat and started streaming over from the NW and by mid-late morning the CU's formed over the airstrip and the wind freshened from the NW. A frontal system which wasn't expected into Dubbo until 4 PM hit the airstrip between 2-3 PM. The wind was to 35 mph, behind that a squall line, with thunder and lightning and general rain. By the end of the day after the passage of the front the atmosphere was trying to clear, but most of the sky was still "stratted" out.

About 1/2 of the field had gotten away before the front hit and it was during the time when that half was getting away that "Charlie" altered the task which was the best thing that could have been done in these circumstances. The pilots who got away reported freshening winds while those left on the ground did battle with the strong winds trying to pack up their gliders before the rain hit.

Thunder, lightning and rain were chasing along those pilots who had launched just prior to the front hitting. Smooth weak 200-300' lift was encountered ahead of the front while lift and turbulence increased the closer the front got to the pilots. Most pilots elected to land before the rain and strong gusty winds became a problem and landed before Eugowra approx. 40-50 km away.

Two pilots flew pretty much in the same area. Both Ian Cummings and Bruce Reeve reported strong lift up to 1000' and pegged close to the dust front and flying at 40-45 mph. Ian stayed high and ahead of the front while Bruce, keeping ahead of the dust front by only a few hundred metres, flew without circling at 1000-1500' AGL for 45km. In that time he radioed Ian that he saw roofing iron cartwheeling across a paddock near Canowndra. At Lyndhurst 500-1000' lift got Bruce back to 7400' ASL. Ian called and said he was at 10,200' ASL, bar to the knees and 1500' up pegged and wisely said he was heading away. It was at least another 20-25 km further on before Bruce could get down, there being strong lift everywhere, speeds easily reaching 45 mph and turbulence quite obvious.

He picked a big 10-acre paddock and hovered backward with the winds gusting to 30-35 mph and only about 40 percent in control of the glider. He finally managed to land safely with only a minor bend in one of the uprights. Ian was blown farther south to Trunkey Creek, 5 km farther on before the dust front hit. He and a farmer watched a tree blow down as he desperately dropped his glider.

Alan Tolley was also somewhere, but much farther to the north and about 25 km back. Ian Cummings 137 km, Bruce Reeve 132.5 km. Their average ground speed was worked out close to 55-60 km/hr for their cross-country. Excitement and drama plus!

Some rather stunned pilots gathered the next morning to relate their individual tales of high winds and horrors. They were told that the front hit Newcastle about 5 PM that afternoon so the collective imagination ran rampant at considering the possibilities of actually flying to the coast in that frontal system (dead or alive!).

It isn't the first time a frontal system has been soared by hang glider pilots but probably the first time that a dozen or so pilots experienced the phenomenon in the same flight. Some may remain scarred/scared forever.

3rd January - 7th Comp. Day

Bob Silver, master story teller, gave an amusing account of his adventure in the Nepal hang gliding expedition and encouraged anyone who was interested to get into the next expedition/adventure as it was well worth it, diarrhea and all.

This morning, after the front, low moist stratus at 2500' AGL and wind freshening a little from the SW. Pilot briefing was delayed until midday to allow the conditions to sort themselves out. A very cool morning this morning, like a cold snap really, what with the SW winds coming up from the Bight. After midday with the base rainy, 15 mph SW and individual CU's now forming, the task was called, Brolgan the goal, then open distance along a corridor 10 km each side of the railway line toward Narromine. Nearly all the pilots got away today and found the drift to be very SW rather than the S that was needed for the run to Narromine, and 20 mph cross winds were the order of the day.

1st Bruce Reeve
2nd Ian Cummings
3rd Carl Braden
4th Alan Tolley/Steve Noble
6th Scott Berry

for the day's placings.

Carl Braden and Ross Duncan flew 105 km and 65 km respectively but were arced back to within the corridor because they had wandered at least 45 degrees off course, which was unfortunate. Mark Berry, a non-comp. pilot, flew an excellent tailwing cross-country of 130 km to way past Wellington.

4th January - 8th Comp. Day

A blue morning with a light SW-W. An inversion was noticed at about 4-5000' ASL but sailplanes were about by mid morning so all was not lost. Bases were predicted by Nostradenis to 6000-7000' with an inversion limiting any further height gains. Stayed blue all day with the inversion lifting very little.

The majority of pilots got away in an afternoon burst at around 2:30-3 PM, half the field made the turnpoint north of Parkes, the task being a race to Wellington (110 km), but didn't get too much farther than that unfortunately.

Val Wallington had the best fly of the day of 118 km to land on the other side of Wellington and in doing so broke 1 World and 4 Autralian records:

o World record for distance to a nominated goal
o Australian women's height gain record of approx 7100'
o Australian general category for distance to a nominated goal
o Australian women's open distance
o Australian women's distance to a goal

5th January - 9th Comp. Day

A blue start to the day with only a glimpse of high cloud to the SW. Ground wind 5 mph from the SW. By mid morning the wind was freshening from the W, CU's over the ranges to our east and high base CU's over the strip by early afternoon by which stage the winds were from the W at 25-35 mph.

Mark Mitsos gave an unprepared but good talk on glider design, sail technology and tip designs. The task was then called, a race to Eglinton, a glider strip NNW of Bathurst, where the sailplanes had called their day off because of the strong winds and turbulence and scoffed when told that their glider strip was our goal for the day.

Only a small percentage of pilots got away today because of the strong gusty conditions. Quite rough air was altogether unexpected and a few pilots went weightless and a couple went "over the falls." The pilots who did get away outlanded flying backwards on their approaches. Carl Braden smoked everyone today and made the goal 140 km away in 2 1/2 - 3 hours, making the strip with 7000' above it, much to the surprise of the glider ((sailplane)) pilots. His best height was 9600' ASL/8000' AGL and he was still nowhere near base. Mark Berry, while not competing, flew 103 km.

6th January - 10th Comp. Day

Mark Mitsos gave a talk on airfoils, double surface battens and tensions, and C.B.'s after which the ropes and reels used in the the comp. where auctioned off.

Dubbo airport forecast winds of S and 20 knots at 2000' ASL to W and 30 knots above that. Some high cloud still hanging around but it was only a thin covering and didn't affect the day at all. The inversion layer was still around but some pilots got to 8600' ASL so that wasn't a problem either. The task was an open window out and return to Alectown West. Denis Cummings won the day making it back 5 km past the turnpoint and Garry Morgan finished 2nd 1 km past the turnpoint while Ian Cummings, Carl Braden, Steve Noble and Bruce Reeve finished at the turnpoint for equal 3rd positions.

Dinner and presentation was held at the RSL Club in Parkes, the final positions as per following chart. Garry Morgan won the PR3 with Steve Noble finishing second.

An enjoyable competition, no pressure stuff this one, which was good. Considering it was the first tow comp. to be held it was in the main well organized. On two days the tasks were unrealistic and on the last day the task called was a compromise so that pilots could get back in time for the presentations, but the majority of tasks called were very good and quite attainable.

Lots of good roads branching out from Forbes and Parkes made pick-ups very straight forward. It was sensible, too, to have corridors to a goal to ensure the pick-ups wouldn't take all evening and to penalize those people who landed in restricted areas.

For the fist couple of practice days the organization was rather confusing but when more tow vehicles turned up everything began running smoothly so by the end of the comp. the tow ups and turn arounds were taking approx. 10-15 mins per strip with 4-5 strips generally being used.

Initially, too, no allowance was made for winds that deviated from the N-S direction until later in the comp. A diagonal SW-NE strip was put in which crossed a couple of N-S strips and turned 45 degrees down another one. Not having cross strips initially was a problem as most competitors were not that keen to launch in the SW-W prevailing afternoon winds. By the end of the comp., the cross and strong wind launches were less of a problem because of the increasing confidence of the pilots in towing up in those conditions. Next time though consideration should be given to having either a couple of cross strips or having them all SW-NE as there were only a few days when the winds were not from the S-W sector.

It was disappointing that more pilots didn't turn up and that the number of pilots dropped as the comp. progressed. The organizers did their best, I'm sure, and of the pilots that flew there many must have left with good impressions of the potential of the place where it wasn't surprising to hear of 100-145 km flies. In the 14 day period, 4 practice and 10 comp. than week ends only it is easier to organize and prepare for than having week ends only.

Plenty of camping and caravans facilities at both Parkes and Forbes, 1/2 hour drive away. High cloud base, low humidity, excellent thermal soaring prospects, big distances still to be done, just speaking with Denis Cummings, "Charlie," the PR3 pilot Garry Morgan who scored a 110 km and 14,400' ASL flight, Val Wallington with her 5 records, the 2 pilots who flew over 130 km ahead of a frontal system, to mention just a few pilots and highlights.

Yes it is a plug for the towing comp. to be held again next year in or around Parkes-Forbes. For some of the best summer flatlands flying to be had in Australia from PR3 to PR5 cruise along to the next comp. It doesn't matter whether you haven't towed before, you'll learn quickly and safely.

Many thanks to Denis, Charlie and Bob Silver, Julie and others who organized, wheeled, dealed and answered phones, to Ted Tomlinson for the use of his property and to the unsung drivers, Peter Duncan, Bernard O'Reilly, Mark Mitsos who drove admirably and to the other drivers whose names are lost to me now, thanks for a very enjoyable competition.
+
01 Ian Cummings
- 4815
02 Carl Braden
- 4540
03 Bruce Reeve
- 3773
04 Alan Tolley
- 2962
05 Gary Morgan (P.R.3.)
- 2892
06 Dennis Cummings
- 2830
07 Ross Duncan
- 2550
08 Steve Noble (P.R.3.)
- 2310
09 Val Wallington
- 2043
10 Trevor Gardner
- 1318
11 William White
- 1203
12 Mark Berry
- 0935
13 Nigel Felton
- 0683
14 Scott Berry
- 0673
15 Jon Bird (P.R.3.)
- 0424
16 John Ritchie
- 0381
17 Phil Ayrton (P.R.3.)
- 0293
18 Dick Sneddon
- 0013
19 Greg Sneddon
- 0000
19 Greg Tanner
- 0000
19 Doug Floyd
- 0000
19 Denis Gilbert
- 0000
19 Steve Gratton
- 0000
19 Andrew Sutton
- 0000
19 Roland Kulen
- 0000
19 Joe Mikus
- 0000
*
1985/07-04

THE 1988 INTERNATIONAL FLATLANDS CHALLANGE PROPOSAL

(A tow-launched hang gliding cross-country event)

In early 1988, Australia will host the 6th World Hang Gliding Championships. Pilots from over 30 countries will travel to Australia to compete in this world-class event. The venue will be the Mt. Buffalo area of Northern Victoria.

Unfortunately, only about a quarter of the expected 200 competing pilots will be completing the contest after a "cut" in the field near the half way mark. Even those pilots who complete the event, although possibly flying in "average" soaring conditions, will not get to experience the "excellent" soaring conditions, which are available in the central-western areas of N.S.W. This area has world-renowned soaring potential.

In addition, few of these visiting pilots and national delegates (and, in fact, few FAI-CIVL officials and delegates) would have experienced the recently developed methods of tow launching, especially as a method of launching for a contest. In order to demonstrate the many advantages of this type of contest to the world organization and leaders, it is proposed to hold "The 1988 International Flatland Challenge" in the Forbes-Parkes area of N.S.W. directly after the completion of the World Championships. A 7-10 day contest is envisaged.

As with all "Flatland Challenges," seminar sessions (usually before the day's task is commenced) will be held. The seminars usually cover topics of tow-launching methods and equipment, hang gliding cross-country skills, safety, meteorology, glider and instrument technology, etc. International participation will be encouraged.

In order to promote this event, it is requested that Australia's FAI delegates at the 1985 World Championships and CIVL meeting at Kossen give formal invitations to all FAI-CIVL executives, delegates and member countries to supply speakers and to send observers and competitors. Because of the nature of tow-launched flatland contests, WE DO NOT HAVE TO LIMIT THE NUMBER OF COMPETITORS.

It is hoped that this event will supplement the World Championships and give those pilots and officials who have traveled so far a hang gliding experience of Australia to remember.

Contest Date: Start about 2 days after final of World Champs, Run 6 to 10 days.

Entry: All information re dates, accomodations, etc., will go out with World Championship entry info. Contest will be open to Australian PR3 (Intermediate) rated pilots and pilots with equivalent overseas ratings and higher ratings. Estimated entry fee A $120.00 per pilot.

Tasks: Open Distance and Race to Goal on days with significant wind. Out and Return Race and Triangle Race on days with light/nil wind.

ALL TASKS WILL BE SET SO THAT FAI NATIONAL AND WORLD RECORDS MAY BE ACHIEVED.

Contest Organizer: Denis Cummings, Dights Crossing, Singleton, N.S.W., Australia 2330 (ph. 065 72 4747)

For ratification by HGFA at 1985 Annual Conference.
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1985/07-05

NEWS FROM EUROPE

by Bart Doets

(Ed: This material was reprinted from April '85 WINGS, the official publication of the British Hang Gliding Association.)

Towing is gaining in popularity, both aero-towing and winch launching. Here in Holland it is still officially illegal although the aviation authority officials tend to look the other way as the hang gliding section of the aero club and the official State Aeronautical Department are working on an official regulation system.

Most towing groups are using winches imported from Germany which are of the static type. Some winches are homemade and of dubious safety. One involves jacking up a car and changing one wheel for an empty rim, using this as a winch drum. The experiment was quite successful and one is lead to wonder whether the system could not be expanded to incorporate a cable cutter, cable threading and a tension indicator. This would make it a very economic snap-onto-the-car winch.

A proper development was triggered by a report of a French towing accident. All towing is done now by the Swiss double bridle system, a double release, the top one going over the control bar, the bottom underneath, to a chest release. As the line angle changes with height the top release is activated, allowing a steeper climb. A release malfunction could cause the bottom bridle to pull the control bar into a stall situation. Some pilots take off with only the top bridle (over the bottom bar to the chest) attached with the bottom bridle hanging free. At a safe height the pilot hooks a karabiner from his bottom bridle onto the line before releasing the top bridle. This means that he can continue to tow in safety to release as normal but prevents the catastrophe caused by premature top bridle release.

AERO-TOWING

Is a serious affair in France. La Mouette have conducted seminars for the trike and glider pilots involved. An example of the efficiency of the system is the XC completed by Jeff Fauchier. After being towed to only 300 ft he released and landed 155 km away. The big advantage of aero-towing is that, like the sailplane pilot, the hang glider pilot can be towed right underneath a promising cloud, in this way there isn't even a need to tow to a high altitude.

To prevent glider pilots from diverging from the path of the trike La Mouette have designed a system that is as simple and efficient as the hang gliders itself. The towline has a velcro joiner that provides strength in sheer to pull safely yet parts easily if there is any major deviation from a safe course behind the tug. When the tug pilot releases, the velcro parts to prevent the problem of carrying around an unwanted towline hanging from your chest! One has to be careful whilst under tow because any large deviation will always speed up the glider and slow down the trike, the glider can get high enough to force the tug to dive. This velcro prevents that danger.
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1985/07-06

TOWING IN ENGLAND

(Ed: The following is also a reprint from the Apr. '85 WINGS.)

Recent developments of equipment and techniques suggest that "Skyting" (the name for Winch launching suggested by the Towing committee) will soon be a major part of hang gliding.

Over the few years that winch launching has been practised in this country, with the honourable exception of one of two centres, it has shown itself to be more dangerous than foot-launch activities. For this reason tow launching of any kind has been banned by BHGA Council and you are NOT INSURED if you take part in Tow launching unless SPECIFIC written authorization has been given by Council.

Those wishing to winch-launch or are already having experience of winch launching by the Skyting system, aero-tow or any other system of tow-launch are asked to make a formal application to: Bob Harrison, Training Officer, c/o BHGA, Cranfield Airfield, Cranfield, Bedfordshire, NK40YR. "Skyting" and aero-tow endorsements will then be issued under the Pilot Rating scheme.

A system is being set up by the Towing Committee to ensure that everyone from winch operator to pilot using a Skyting system has adequate training and knowledge to operate safely. It is envisaged that ab initio training will soon take place under the Skyting system. When this is authorized Pilots who have learned this way will have to receive a "Footlaunch" endorsement before ordinary hang gliding clubs can safely let them fly club sites.

Demonstrations have already taken place around the country and if you require a demonstration of a system which (at the time of publication of this magazine) is undergoing scrutiny for approval by the BHGA, contact: Tony Webb of Lejair, 39 The Street, Poringland, Norwich, Norfolk.
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1985/07-07

TETHERED TRAINING

Dear Donnell,

I have been going to write you for years and thank you for the work you have been doing. Because of your bridle system I have been able to fly much more than ever before.

In the past I would average 10 hours a year flying time because of being located in northern Minnesota. I would have to travel to Michigan, out West, Tennessee or other places to get air time. Some times the weather didn't cooperate with my vacation.

Because of your bridle I have 450 skyting flights. I am now averaging 30 hours a year and have towed up to 2700 ft and had 4 cross country flights, none of which would have been possible before.

Bill Cummings, with whom I share your newsletter, had 4 cross country flights in April, the fartherest being 35 miles. Flying that far is hard to do up here because of few landing fields and surrounding forests.

I enjoyed "The Skyting Challenge," by Doug Gordon, in SKYTING, No. 36. In his article he showed his concern about teaching first-day flyers to skyte safely. I agree with him 100%.

This is how I solve that problem. I drive a stake into the ground on the beach with 30 to 40 ft of rope hooked to the bridle. I also attach a 15-foot rope to the nose of the glider so that I can regulate the height of the flight: When the winds get up to about 10 to 20 mph, the pilot can fly 5-10 feet off the ground, thereby learning to control the glider from only about 5 feet in the air. On a good day, when the wind is not gusty, he can fly for 30 minutes to an hour. When he gets tired and wants to rest, he can also learn by watching others fly. Besides it's a lot of fun.

After a novice has gained skill in this manner, his confidence is up. So when he is ready for the training hill he will fly straight and level flights.

I believe this method of learning to fly could be used all over: at lake beaches, ocean beaches, flat land and large fields. Well, this is just a suggestion.

I am not very good at writing; so I haven't gone into great detail. I hope I have given both the instructor and flyer some ideas.

I enjoy reading your newsletter. Keep up the good work.

Gene Stone
Grand Rapids, MN
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1985/07-08

WARNING!

You may have noticed that this issue of SKYTING is back down to 6 pages (instead of the previous 8). This is because of the reduced amount of material I am receiving from you.

I hope your lack of communication means that you are having so much fun skyting that you simply do not have time to sit down and write about your experiences, and that you are encountering no new problems or unexpected surprises.

But regardless of the reason, if you don't sit down NOW and write that letter you have been putting off, you are going to have to listen to an awful lot of my own jabber in the next issue of SKYTING.

Donnell Hewett
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