instructors and other qualified pilot fiends

General discussion about the sport of hang gliding
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Tad Eareckson
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

The United States Hang Gliding and Paragliding Association, Inc.

Standard Operating Procedure
12. Rating System
02. Pilot Proficiency System
02. Rating Requirements
07. Novice Hang Gliding Rating (H-2)
-A. General Description

The pilot understands the USHPA paragliding rating systems and recommended operating limitations.
Yep. That WOULD explain a few things.
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Tad Eareckson
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

Hang Gliding - 1992/03

1991/12/15 - Michael Elliot - 27 - Novice - Pacific Airwave Double Vision - Lookout Mountain Flight Park

Novice pilot went tandem with experienced tandem pilot in preparation for first solo altitude flight. On the base leg of the landing approach, flying crosswind over the treeline, the attempt to turn onto final was unsuccessful. The inability to turn onto final may have been caused by thermal activity, the passenger interfering with glider control, or both. The glider continues straight, hit a tree, and side slipped sixty feet. The novice passenger was killed on impact, the tandem pilot was seriously injured.
Hang Gliding - 1992/03
- So it's been over two months since the atrocity - so we should know everything by this point.
Lookout Mountain Flight Park
- And what are the odds that this report DIDN'T come straight off of the desk of Matt Taber - with no external review whatsoever?

http://www.hanggliding.org/viewtopic.php?t=20756
How is Zach Etheridge doing?
Bob Flynn - 2011/02/04 11:26:34 UTC

Lookout keeps this kind of stuff under their hat. You never hear of accidents there. But every time I go there, I hear about quite a few. Blown launches, tree landings, etc.
- Guess occasionally you get something too big even for Lookout to cover up, huh?
Novice pilot...
- Meaning that he's undoubtedly completed his solo training on the Lookout training hills...
The United States Hang Gliding and Paragliding Association, Inc.

Standard Operating Procedure
12. Rating System
02. Pilot Proficiency System
02. Rating Requirements
05. Novice Hang Gliding Rating (H-2)
-B. Required Witnessed Tasks
02. Demonstrated Skills and Knowledge

-i. Demonstrates 180 degree turns in both directions, and at various speeds and bank angles.
...and is supposed to have some vague idea how to make the 90 degree turns required to go from downwind to base and base to final - or at least be of some use to another pilot on a tandem kite with similar objectives in mind.
...with experienced tandem pilot...
- Bo Bent-Pin Hagewood.
...in preparation for first solo altitude flight.
- Versus in preparation for more tandem flights.

Probably meaning that he'd have been cleared for solo off the ramp if he had survived the check ride with his experienced tandem instructor. (Kinda makes you wonder how much worse he'd have done without an experienced tandem instructor helping him approach the LZ (and using him to cushion the blow).)
On the base leg of the landing approach, flying crosswind over the treeline...
Lookout Mountain Flight Park

The LZ provides a large and safe landing area with plenty of smooth grass. The LZ is 2600' x 1000' (about 44 acres), about one mile in front of launch.
- How important is it to fly base over a treeline at the Lookout LZ?
...the attempt to turn onto final was unsuccessful. The inability to turn onto final may have been caused by thermal activity...
- How very odd. I'm not sure I've ever heard of thermal activity being the cause of an inability to turn onto final. I've heard of plenty of idiots being unable to turn onto final 'cause they were too slow - but never 'cause of thermal activity.

- How many other times in the past thirty-three years has somebody been unable to turn onto final into that field 'cause of thermal activity?

- If you can be doing everything right and get killed for the sole reason that a turn onto final is prevented by thermal activity, is it really safe coming into that field in thermal conditions? Maybe you really need a bigger, flatter, safer field.
...the passenger interfering with glider control...
- Oh. At the beginning of the paragraph he was a rated pilot - with a card that says he can fly a site like that solo and unsupervised. And, under Lookout's instructional program, he was doing what was probably a final check ride before getting cleared to solo off of THAT ramp into THAT field. Which would ALSO mean that he was the one flying the glider virtually the whole time.

But NOW he's a PASSENGER *INTERFERING* with glider control - while Bo is valiantly but futilely struggling against him to turn onto final and save both of their lives.

- Who was the designated fucking Pilot In Command for that flight?
...or both.
- We don't KNOW?

Was Bo's short term memory wiped? If so, how come you're not saying so?

Or is it just a lot better for Lookout if everybody is led to believe that and wanders off and forgets everything without asking a whole lot of embarrassing questions?
On the base leg of the landing approach, flying crosswind over the treeline, the attempt to turn onto final was unsuccessful. The inability to turn onto final may have been caused by thermal activity, the passenger interfering with glider control, or both.
- How did the glider get onto base that low over a treeline at the edge of a wide open flat field half the size of Nebraska in alleged thermal conditions allegedly strong enough to maybe prevent the glider from being turned onto final?
- a) The passenger interfered with glider control.
- b) Thermal activity delayed the turn from downwind.
- c) Both.
- d) None of the above.
Christian Thoreson
Flight School Director - 1990-2004
Lookout Mountain Flight Park
~2004/04

That man will die in a hang glider.
- e) Maybe we should ask Christian's opinion - and get some of the data that went into forming it.
...or both.
- Yeah, better make it both.

The kid was shot just off his back yard possibly because his International Orange windbreaker was a bit faded, possibly because he was looking for his lacrosse ball ten yards into the brush. Probably both reasons.

OK, next item on the agenda... Extending the doe season.
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Re: instructors and other qualified pilot fiends

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http://www.hanggliding.org/viewtopic.php?t=22212
So long guys

Doesn't get much better than that.
Now if only Davis will lock out and smash into Adam.
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

Hang Gliding - 1990/02

Barbara Flynn

Aerotowing
At Its Best--In Florida

A few years ago I wrote off "aerotowing" as a safe and reasonably means of getting into the air. The takeoff speeds seemed excessive and the tow too difficult. However, thanks to Bobby Bailey, Campbell Bowen and other Florida pilots, my perspective on aerotowing has changed.

These Florida flyers developed an improved system for "aerotowing" that tows the hang glider at EXACTLY the right speed (22-30 mph) and is comparable to the case and consistency of traditional sailplane towing. Local pilots preparing to tow at our field show less apprehension than is exhibited by most pilots preparing to make a no-wind mountain launch. This has allowed our group to concentrate on finding and releasing in the best lift to consistently soar. "It's the best way to fly a hang glider and the most efficient way to get to where the lift is. Wind direction no longer makes a difference," says Mike Pleskovich.

The average climb rate on tow in stable air is 500 to 600 feet per minute. Our tug pilots, Bobby Bailey and Russell Brown, generally will not signal the glider pilot to release until they have located lift that has increased the rate of climb to at least 1,100-1,200 feet per minute, as indicated on the tow plane's rate of climb indicator.

Intermediate pilots advance quickly in their thermaling skills by being dropped off in 400 foot per minute thermals at the tug pilot's signal. Advanced pilots usually indicate their destination cloud or cloud street to the tug pilot prior to takeoff. Imagine pointing to any cloud in a six-mile radius and being there with ten minutes! Your our five pilots can be towed into the same thermal, and in turn, each climb to cloud base. Occasionally, the thermals are so short cycled that the cloud or cloud street has dissipated by the time you reach it. In these conditions the tug pilot will watch for a developing cloud during the tow and, as in all tows, use the tug's vario to locate and center the best lift. The tug climbs and sinks with respect to the horizon, indicating thermal activity. The movement of the tug's wing warns the pilot of impending turbulence with approximately a five- to six-second delay before the glider reaches the turbulent area.

Early morning and late evening hours are the best time for introductory flights and warm-up flights. The stable conditions during these periods of the day make the tow segment of the flight very smooth. The greatest obstacle is getting the new pilot to relax and believe that AEROTOWING REALLY IS EASY.

Pilot-induced oscillations are the major cause of problems during the first few tows. Often, after the pilot has climbed away from the runway, he will settle down and get in control of the oscillation. Other times the oscillation becomes so great that he will release or break the weak link, releasing him from the tug. The experienced tug pilot will also watch the pilot carefully, and if the pilot is unable to control the oscillation will release the glider from the tug end. Most intro-tows go all the way to 2,000 feet once they get above 500 feet. "The tow is almost as fun as the free flight," as Mike Pleskovich says. The pilot can actually be towed around and between cloud streets allowing a spectacular view, while experiencing the changes in atmosphere and temperature. First-timers come back with that "fudge-eating" look on their faces. Many take another flight right away.

Getting the maximum number of flights in safely during the most thermally-productive part of the day takes organization on the ground. The round-trip flight for the tug to tow a glider to 2,500 feet and back is less than ten minutes. All pilots are encouraged to take high tows and to wait to release in the best lift. This reduces the number of second tows per pilot. Twenty flights per day to an altitude of 3,000 feet or above is not uncommon.

Since March 1989, the Florida pilots have flown 36 consecutive weekends, totalling more than 750 flights. Out-of-state pilots who have heard about our system visit the flight park to try it out. A recent visitor from Alabama said the system was "fantastic...much easier than any other towing I've ever done." Steve Moyes, who recently visited and flew the site, said it was "great...the best tow I've ever had." Advanced pilots have flown to both the east and west coasts of Florida and have gained 7,200 feet of altitude above the launch elevation. When conditions are favorable, these pilots will break the state distance record of 72 miles by flying a path to the north or south.

There are five major differences between our system and previous aerotowing systems:

1) The most important change is the modification of a King Cobra ultralight with high-lift devices to fly comfortably, controllably, and safely at hang glider cruise speeds. Stall speed on the tug is around 20 miles per hour. The tug does not actually stall break, but mushes instead. Best climb is between 22-30 miles per hour, the perfect speed to pull a hang glider. On a few occasions the tug pilot has flown too slowly and caused the glider to sink below the tug, momentarily out of position.

2) The King Cobra, three-axis control ultralight, has a large, robust airframe allowing the use of a powerful and super-reliable water-cooled 65 horsepower Rotax engine, turning a big 72-inch prop. This package produces a consistently strong climb rate and allows a quick climb out of turbulence near the ground.

3) The ground launch vehicle (GLV) that cradles the control bar and keel of the glider, allows the pilot to be proned-out for maximum control, and the glider to be trimmed to just below the optimum angle of attack during launch. When the pilot feels there is sufficient airspeed for liftoff, he simply pushes out and flies off the GLV. Launches with a slight tailwind or crosswind are easily accomplished with the use of the GLV. Run-offs, under these conditions, are next to impossible. Our first GLV was built by Mike Pleskovich approximately two years ago and was used for truck towing. Mike's GLV worked so well for truck towing that we tried it for aerotowing, and it has become an important part of the system. Thanks, Mike! We rarely have to change ends of the field because of a change in wind direction.

4) A "center-off-mass" towing bridle is used at both ends of the tow line. The tug has a cable-braced mast that places the upper attachment point of the 15-foot bridle above the rudder, with the tow-plane release below the rudder. The bridle goes through a ring on the end of the tow rope which acts as a pulley, and then attaches to the release on the tow plane. The bridle allows the glider to fly in a 30 degree envelope without affecting the pitch pressure of the tug. Having a two-point bridle attached to the glider pilot reduces pitch pressures by raising the tow point closer to the center of drag. Towing pressures are very low. Lighter pitch pressures make the glider much easier to keep in proper position and more comfortable to fly. The bridle attaches at the pilot's shoulder straps, passes through the ring attached at the end of the tow rope, and is attached to a release and the pilot's carabiner. The bridle attaches to the release through a weak link. The weak link is made out of 130-pound competition dacron fishing line. Competition fishing line is designed to break at one pressure consistently, which makes it an ideal weak-link material. The actual line pressure is approximately 200 pounds, distributed between the two bridle attachment points. The weak link also protects the glider pilot because the link will break before the glider can roll up to 45 degrees.

5) A 300-foot tow line was used for beginners and then adopted as the best length line for ALL PILOTS, because it makes handling thermal turbulence so much easier.

As a female pilot who has been flying and boat towing for ten years, I could not imagine that aerotowing would be this easy or this much fun. I was towed to 2,000 feet on my first aerotow, and when I landed I was anxious to go back up again. Within a few flights I was flying in peak conditions.

Then, one warm October Sunday, I watched as the cloud streets built and waited my turn. After a short conference with the tug pilot we picked out a building cloud and took off. I released at 2,800 feet in 500 foot per minute lift, and after a few minutes of thermaling reached a cloud base at 3,600 feet. Now I had to work to stay out of the cloud by flying out into 200 foot per minute sink for a few minutes, and then returning to climb back up to cloud base. Below me I could see the tug pulling another pilot up and in the distance, at cloud base, was another pilot. Within minutes there were three of us soaring in the same thermal. For the next fifteen minutes we drifted with the thermal downwind, and as the cloud dissipated headed back to the field, watching the sun set below, the clouds on the horizon. For me, no other type of flying can match the ease, comfort, thrill, or fun of aerotowing.

The Florida hang glider pilots aerotow every weekend at a small independent ultralight airfield near Clermont, Florida, known as the Florida Gators Airpark. The Florida Gators Ultralight Association, Inc., is an active and well-organized flying club. The Gators are enthusiastic about, and dedicated to, the sport of recreational flying, and are supportive of the addition of hang gliding to their regular flying activities at the field. We are glad to have become a part of this group.

If you would like more information on our aerotowing system or would just like to come fly with us, contact Campbell Bowen at (407) 657-1699 or Steve Flynn at (904) 775-3252. We will be happy to introduce you to aerotowing at its best.

On April 13-15 the Florida State X-C Meet will be held at the Florida Gators Airpark in Lake County, Florida. Call one of the phone numbers above for more information.--Ed.

-

Russell Brown tows author and pilot Barbara Flynn aloft. Photo By Bill Otis.

Bobby Bailey pilots the King Cobra ultralight which is designed to fly at hang glider speeds--22-30 mph. Mike Pleskovich under tow) designed the ground launch vehicle. Photo by Bobby Bailey.

Bill Otis about to launch from the GLV (ground launch vehicle) which allows "truck tow" type takeoffs. Photo by Russell Brown.

Bobby Bailey tows Gregg McNamee to the best lift. Photo by Bill Otis.

The author about to soar over Florida's flat countryside. Photo By Bill Otis.
The ground launch vehicle (GLV)...
There's a term that you don't hear very often nowadays.
A "center-off-mass" towing bridle is used at both ends of the tow line.
- It isn't used at either end of the towline.
- There's no such thing.
The tug has a cable-braced mast that places the upper attachment point of the 15-foot bridle above the rudder, with the tow-plane release below the rudder. The bridle goes through a ring on the end of the tow rope which acts as a pulley, and then attaches to the release on the tow plane.
I'm not hearing anything about a weak link. But why bother following existing safety regulations? This is hang gliding.
The bridle allows the glider to fly in a 30 degree envelope without affecting the pitch pressure of the tug.
Nope. If the planes aren't lined up the pitch trim is being affected.
Having a two-point bridle attached to the glider pilot...
A two point bridle attaches to the glider pilot AND the glider.
...reduces pitch pressures by raising the tow point closer to the center of drag.
I wish the Cosmos people had figured that out.
Towing pressures are very low.
Yes. PRESSURES. If a hang glider pilot ever uses the word "TENSION" he gets his all towing related qualifications suspended for a period of eighteen months.
The bridle attaches at the pilot's shoulder straps, passes through the ring attached at the end of the tow rope, and is attached to a release and the pilot's carabiner.
Is it worth mentioning anything about the actuator or its location? Nah, basetube... downtube... whatever. We've got a weak link, don't we? So what's it matter?
The bridle attaches to the release through a weak link.
Great. So if the bridle wraps at the tow ring, what's the plan for separating from the tug with no secondary release and no weak link anywhere in the system? But, hey, why bother following existing safety regulations?
The weak link is made out of 130-pound competition dacron fishing line.
http://ozreport.com/12.081
Weaklinks - the HGFA rules
Davis Straub - 2008/04/22 14:47:00 UTC

From section 3.4 of the 1999 Hang Gliding Federation of Australia Towing Manual:
Recommended breaking load of a weak link is 1g. - i.e. the combined weight of pilot, harness and glider (dependent on pilot weight - usually approximately 90 to 100 kg for solo operations; or approximately 175 kg for tandem operations).
Here is the requirement from the 2007 Worlds local rules (which I wrote) for weaklinks:
Pilots must use weaklinks provided by the meet organizers and in a manner approved by the meet organizers. All weaklinks will be checked and use of inappropriate weaklinks will require the pilot to go to the end of the launch line to change the weaklink.

Weaklinks will consist of a single loop of Cortland 130 lb Greenspot braided Dacron Tolling line and should be placed at one end of a shoulder bridle.
At the 2008 Forbes Flatlands Greenspot for the first time was used as the standard weaklink material (thanks in large part to the efforts of Bobby Bailey). We applaud these efforts to improve the safety of aerotowing by using a better weaklink material.
Yeah, thanks Bobby. If aerotowing safety evolution continues at this rate, by the year 2026 everybody will still be forced to use 130 pound Greenspot on ONE end of a shoulder bridle and Davis still won't be paralyzed from the neck down - just still from the neck up.
Competition fishing line is designed to break at one pressure consistently, which makes it an ideal weak-link material.
ABSOLUTELY. It makes no difference what that PRESSURE is - the important thing is that it's CONSISTENT. For over twenty-one years now people have been doing nothing but RAVING about how ideal it is - especially right after it pops.
The actual line pressure is approximately 200 pounds...
Bullshit. It's a lot closer to half that. But since when did aerotow people give a rat's ass about actual numbers anyway? Most of them can't count beyond six with shoes and mittens on.
The weak link also protects the glider pilot because the link will break before the glider can roll up to 45 degrees.
Sure it does. It did in 1980, it did in 1990, it does in 2011, it will FOREVER. And you'll always be able to get away with publishing shit like that in Hang Gliding magazine with no fear of a reality check whatsoever.
A 300-foot tow line was used for beginners and then adopted as the best length line for ALL PILOTS, because it makes handling thermal turbulence so much easier.
It also helps put the planes out of sync with each other when flying through thermals. Shorten it up a little.
And the Bailey-Moyes Dragonfly promo tour hit the road the following year.
Aerotowing
At Its Best--In Florida
Yep. In actually WAS at its best in Florida twenty years ago. Mainly 'cause the Florida crowd and its clones have made REAL sure it would NEVER get any better.
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Tad Eareckson
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=22212
So long guys
Allen Sparks - 2011/06/19 13:21:25 UTC
Evergreen, Colorado

it is sad that Jim left.
Yeah Spark, real shame.
I'm wondering how this made it's way to the basement so quickly?
Yeah, how 'bout that, Jack? How did IT MAKE ITS WAY to The Basement so quickly?
Rich Jesuroga - 2011/06/21 04:20:41 UTC
Salida, Colorado

Not good that Jim left.
Rick Cavallaro - 2011/06/21 04:34:17 UTC
San Francisco Bay Area

I couldn't agree more. I always felt Jim was one of the most intelligent and level headed posters here.
Precisely. And on the Capitol club and Oz Report forums as well - for precisely the same reasons.
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=24042
Tullio Gervasoni pulled from the Italian pilots at the Worlds
Davis Straub - 2011/06/22 18:19:43 UTC

This totally sucks.

Tullio Gervasoni's name was pulled from the pilot list that I saw this morning. It is my understand that Tullio has been pulled from appointed Italian pilots because of the article that I published this morning. Apparently a number of Italians are quite angry with my article. Since, it was I felt a very innocent article just pointing out the FACT that the Italian system (and others) use a subjective criteria (which I critique), I've got to wonder about the sensitivity of these people.

Now they have taken a despicable action. Pulling a pilot from their "team" because whatever conclusions they reached because of what I wrote. Perhaps the Italians aren't familiar with the term, "Freedom of Speech." This is despicable. It shames the Italian team and the Worlds.

I wonder now if they will try to get me pushed out of the Worlds?
There are ACTUALLY people in HANG GLIDING *DESPICABLE* enough to eliminate flying and community participation opportunities for other people just because FACTS have been publicly stated?!?!?! I'm SHOCKED! SHOCKED!!!

http://ozreport.com/forum/viewtopic.php?t=592
Linknife
Davis Straub - 2010/04/03 12:46:26 UTC

Tad is gone.
http://ozreport.com/forum/viewtopic.php?t=22660
What can be learned from this "scooter" towing accident?
Davis Straub - 2011/02/07 19:21:29 UTC

Okay, enough. On to new threads.
Did you get all your principles removed along with your tonsils when you were six years old? How much extra did it cost? Or was it a freebie 'cause you really never had much detectable to begin with?

Slimy goddam motherfucker.
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Tad Eareckson
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

http://www.flyfunston.org/bbs/viewtopic.php?f=5&t=1108
Wallaby Ranch
Charlie Nelson - 2011/03/11 05:28
Redwood City

I flew the Ranch Feb 25 ..and got an extended sledder, breaking a weak link at 2100 . One pm conditions were soarable but turbulent on tow. My arms were completely tired out due to the heavy bar pressure towing a rental Sport 2 from the carabiner. should have pulled on more VG . oh well , it was fun. took a ground school from Mike Barber on March 8.
Chris Valley - 2011/04/28 04:34

Hey Charlie,

Tell us more about this trip...sounds like you had fun...what were the thermals like?
Charlie Nelson - 2011/03/11 05:28

Mr Calif Redemption Value, Thermals were broken and tricky to track. Mike Barber and two others went XC, while myself and 10 others sank out after 20 minutes.

the tow was as rough as Calif, ..not a typical day . the tow pilot said it was the 3rd roughest day he'd ever seen at Wallaby. I broke a weak link at 2000', was going for 3K . should have pointed my nose at the tug's right wing tip as he entered the turn , but I went too wide and snapped it .
I only tried to fly 2 days
One pm conditions were soarable but turbulent on tow.
As opposed to being soarable but glassy smooth on tow.
My arms were completely tired out due to the heavy bar pressure towing a rental Sport 2 from the carabiner.
Wills Wing

Sport 2 135, 155
- On keel, at back of bottom surface zipper
So you're renting a glider from an aerotow park but they can't be bothered to rig it for safe towing?

http://www.wallaby.com/aerotow_primer.php
Aerotow Primer for Experienced Pilots
The Wallaby Ranch Aerotowing Primer for Experienced Pilots - 2011/06/26

Welcome to Wallaby Ranch, the first and largest Aerotow Hang Gliding Flight Park in the World! We're the aerotowing (or "AT") professionals; no-one knows AT like we do; it's all we do, and we do it everyday, year-round.
Yeah, right.
should have pulled on more VG .
Ever wonder why Wills Wing ships gliders with VG systems built in but the release "system" is just some piece o' shit slapped on by some asshole at a flight park?

Which one of those systems:
- is more critical to the safety of a flight?
- was more important with respect to your ability to control THAT flight?
Where was your release actuator? Could you have accessed it in an emergency? (Just kidding.)
...breaking a weak link at 2100 .
Were you using a weak link specified for the glider by the manufacturer? Or were you using some piece of fishing line handed to you by some asshole at a flight park?
...took a ground school from Mike Barber on March 8.
What were his comments on your weak link failure and the appropriateness of its rating?
should have pointed my nose at the tug's right wing tip as he entered the turn , but I went too wide and snapped it .
Too wide for what? The tow or the weak link?
Well, OBVIOUSLY the tow. So why didn't release before things got that dangerously out of control?
I only tried to fly 2 days
Yeah, TRYING to fly is so much more fun than actually DOING it.
oh well , it was fun.
GREAT! Life is always so much more fulfilling when your standards and expectations totally suck.
Wallaby Ranch - 2011/06/26

When done properly, AT is your gateway to longer, higher, hassle-free flights, and more airtime with less effort than ever before.
So how many more decades is it gonna take you assholes to start figuring out how to do it properly?
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

http://ozreport.com/15.125
I am completely ashamed that I got Tullio kicked off the Italian team
Davis Straub - 2011/06/24 12:52:29 UTC
Sigillo, Italy

I wish I had never published that article
And yet, not the slightest twinge of guilt about all the people you've helped get mangled and killed. Well, maybe the ones whose crashes have resulted in cancellation or invalidation of the day's task.
I wish I had never published that article.
And I wish you had never been born. But, failing that, keep flying with your Pro tow Mini Barrel Release and Bridle (only forty dollars) and 130 pound Greenspot safe towing system focal point to keep our hopes alive. And don't forget those hang checks!

:D
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Tad Eareckson
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Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

Hang Gliding - 1996/12

An Aerotow Release System
Gregg B. McNamee

BACKGROUND

Over the past 10 years I have been towed aloft by several boats, a modified Cobra and the Dragonfly. I launched first from the shore, then later from the back of the first boat in Florida equipped with an ATOL-like winch and launch system. (Jim Walls equipped my Ski Nautique with a payout winch and a launch platform after reading about the ATOL trailer launch system.)

Towing was making great strides forward. Center-of-mass bridles were being developed and tested to enhance the pilot's ability to control the glider while under tow. New releases were being tested on every flight to examine the safest options available. Bobby Bailey modified a Cobra ultralight to tow hang gliders and ultralight sailplanes, then designed the Dragonfly, a task-specific ultralight designed to aerotow ultralight aircraft.

Many thousands of tows, and years of flying under tow, have taught us techniques to safeguard pilots from some equipment-related problems. Like most pioneers, when someone was hurt or something went wrong, we learned what not to do and what to avoid. In time we arrived at how to do it right, and would like to share that information in order to help the towing community avoid some of the accidents and incidents from which we learned. The time-proven information is meant to help pilots have a safe, successful and more enjoyable towing experience.

THE AEROTOW RELEASE SYSTEM

The Aerotow Release System consists of four components that work together to provide the pilot with enhanced glider control while under tow, and the ability to terminate the tow at the pilot's discretion. The components are the pilot's release, secondary release, bridle and weak link (see Figure 1). Each element in this system is equally important to the safety of the pilot.

PRIMARY RELEASE CRITERIA

1) To actuate the primary release the pilot does not have to give up any control of the glider. (Common sense tells us that the last thing we want to do in an emergency situation is give up control of the glider in order to terminate the tow.)

2) The primary release must disconnect the towline from the glider at the pilot's discretion and not before. (The inability to release or premature release can have serious consequences for an unsuspecting pilot.)

3) The pressure required to actuate the release must not be more than three to five pounds throughout the entire towline tension range (from zero tension to the maximum strength of the weak link).

If your system requires you to take your hand off the control bar to actuate the release it is not suitable. If your release opens as a result of abrupt changes in towline tension you are using another unacceptable release mechanism. If the pressure required to actuate your release increases as the towline tension increases, or will not drop the towline in zero-tension situation, you should rule it out as well.

POSITIONING THE PRIMARY RELEASE

The release handle should be on the control bar, but not positioned so that the launch cart or the pilot might actuate it by accident. The release cable needs to be routed and secured so the pilot is provided with a full range of movement without causing an unanticipated release. The release mechanism itself can be connected to the carabiner on most intermediate and high-performance gliders. This will help reduce bar pressure at higher towing speeds. Slower gliders require that the release mechanism be attached to the keel in front of the control frame junction to reduce the bar pressure experienced by the pilot during the tow. The farther forward the connection, the less the bar pressure will experience. In the process of trying to find the right position make small, gradual changes. If you have to push out during most to the tow you have moved the attachment point too far forward. Move the attachment point back until the bar pressure is neutral or causes you to pull in slightly during tow. Make all release mechanism location changes in small increments so that you experience fewer surprises on your next flight. Changing the location of the release mechanism is one way to trim the glider for towing without affecting the normal trim of the glider during free flight.

THE SECONDARY RELEASE

The secondary release is a backup. If the primary release fails or the bridle gets hooked on the towline, you'll be glad you have a secondary release. Some pilots use a hook knife as a "secondary release," but I prefer an equestrian emergency release on the shoulder of my bridle. That way, if, after actuating the primary release the bridle becomes entangled with the tow ring, I can use my secondary release to detach from the towline. Note in this scenario that the weak link is no longer part of the aerotow release system and it is very important to be able to detach from the towline immediately.

POSITIONING THE SECONDARY RELEASE

The secondary release needs to be within reach and sight of the pilot without requiring you to look away from where you are going. You also want to consider the position of this release relative to your face, so that if the towline breaks under a lot of tension the secondary will not hit you in the face. If you use an equestrian emergency release be careful not to get one with such a large collar that when you snatch on the towline the mass of the collar causes an unwanted detachment from the towline.

THE BRIDLE

The bridle is the part of the system that enhances the pilot's ability to control the glider while under tow. It allows the pilot to change his pitch position relative to the tug without causing him to struggle against the tow tension, because the towline ring is able to slide to a new location on the bridle without resistance. The bridle also permits the pilot to effortlessly move side to side without having to fight the towline tension, making the ever-useful flat turn less difficult than with a more restrictive bridle arrangement. Flat turns or yaw-like turns are very useful for controlling the glider under tow, so a proper bridle will not restrict the pilot's control movements. You can see though that this system tows the glider through the pilot, as opposed to older arrangements that towed the glider while the pilot attempted to maintain control. This bridle also helps keep the glider in position. If the towline tension increases, the pilot's weight is pulled forward, helping him to speed up with less effort. If the glider is off to one side, the pilot's weight is pulled to the appropriate side, moving the glider back into position.

CONNECTING THE BRIDLE

The bridle consists of two ropes: the first rope with its ends connected to the shoulder straps of the harness, and a span of rope between the ends tow to three feet in front of the pilot's head. This is the rope on which I connect the secondary release in-line. The rope acts as a slide for the loop of the second rope in the system, allowing the pilot side-to-side movement. With this sliding loop connection the second rope's span continues through the tow ring, then is connected by the weak link to the release mechanism. Do not make the second rope so short that in the slowest flying position the first rope comes to the ring on the towline, or to where the towline ring is close enough to the pilot to hit him if the towline breaks. When attaching the first rope to the shoulder straps connect them near the apron of the harness. If you attach the rope higher you will find your head caged in between the first rope while under tow. If your harness has tow loops sewn at the junction of the apron and the shoulder straps, connect the first rope's ends there. There are no knots in the bridle system so that the rope can slip through the rope loop or the towline ring without restriction.

WEAK LINK CRITERIA

The weak link utilized in this system is one loop of 130-pound test Dacron fishing line -- no nicks or frays. When I started towing, years ago, the tow rope was the weak link, and would literally fail the airframe of the glider if the tow pressure was too high. I prefer to learn by example rather than practice, so I accept no substitute when it comes to weak links.

WEAK LINK CONNECTION

As mentioned, the second rope in the bridle system has a spliced loop at each end. One end slides on the first rope and the other end is where the weak link is connected. The weak link is wrapped around the loop four or five times, then tied twice with a non-slip knot. Any single loop that is NOT immediately adjacent to the knot may be used to connect to the primary release mechanism. The loop should NEVER be longer than half the diameter of the tow ring it must pass through. This avoids the ugly situation in which the weak link is long enough to go around the ring on the towline, thus reattaching the towline to the glider. This would immediately double the tow line tension experienced by the pilot until the weak link broke.

CONCLUSION

As you can see, the components of this system work together. If you accidentally used the wrong link, the releases would be trying to work under greater tension (maybe beyond their working range). This bridle system delivers half the towline tension to the pilot and half to the glider. The ability of the tow ring to slide on the bridle enables the pilot to use less energy to adjust the pitch of the glider. The primary release mechanism connected to the carabiner helps move the pilot's center of mass forward as the towline tension increases; the weak link end of the bridle and the shoulder strap ends of the bridle pull the pilot's weight forward. In the same way, the second rope slides on the first rope to assist the pilot's lateral control movements.

Don't forget that you still have a bridle after releasing from tow, but it disappears from sight. If you leave it over the bar and come in low over something, you will wish you had at least put it under the control bar, if not in the front of your harness.

I hope this information helps prevent those in our towing community from reliving the experiences that have brought us to this point. We just don't live long enough to make all the mistakes ourselves. Stay safe and have fun!
-
Gregg McNamee is a USHGA Advanced Tandem Instructor, Aerotow Supervisor, Honorary USHGA Board Member, a Basic Flight Instructor with USUA (U.S. Ultralight Assn.) and owner of GrayBird AirSports, an aerotowing flight center in Florida.
Tad Eareckson - 1996/12/06

Aerotow Release System comments

I am writing regarding some of the recent published discussion regarding aerotow bridle/release configurations, primarily Gregg McNamee's article in the December issue. Although the issues may be fairly minor, I think it's fairly safe to say that release configuration and reliability problems were large looming factors which reduced the rosters of the local club by two and of the region by three this past season.

I would first amend Gregg's description of the bridle components to suggest that they be fabricated from low stretch material (e.g. Dacron, Spectra) rather than perlon (= nylon) to make things a little less lethal to one's face in the event of failure under load and to eke out a tiny bit more efficiency under tow. It's also not a bad idea to use a thimble in the splice in the primary bridle through which the shoulder-to-shoulder bridle is threaded to reduce friction and wear.

To address Don Hewett's concern about the danger of this threaded system jamming at low altitude (November Tow Lines) I would say that it appears to me that this is something of an evil necessitated by the safety enhancement of a control bar mounted actuator, an evil perhaps minimized by using a heavier, stiffer material than is sometimes seen and ensuring that smooth splices are used in both ends.

Although the practical risk may be so small as to hardly be worthy of mention, there is a hypothetical possibility of the secondary release described in Gregg's article failing in precisely the manner of the above concern. The secondary release incorporated in my system is a leech line Lark's Head with Toggle (check a knot book), the toggle being a tiny cotter pin with a short lanyard attached, everything safetied with a light wrap of masking tape.

To further address the danger of a primary release failure, a secondary weak link, of strength somewhere between significantly stronger than and double that of the primary, should be installed at the other end of the primary bridle. Note that a double strength link will fail at a somewhat higher tow tension than is allowed by the primary, as the primary bridle has ceased being a bridle and is now an extension of the towline (as explained in Dennis Pagen's and Bill Bryden's November article), but you'll still be in a reasonable ballpark. Also note that this secondary link may make the effects of the snagging of a trailed primary bridle (the potential for which is illustrated on the December issue's cover) a lot easier to live with.

The illustration of the system in Gregg's article depicts the carabiner in a configuration less than ideal for the upwind end of a parachute bridle to negotiate.

Finally, if you're flying with a release mechanism that would require significantly more force to actuate in the event of too strong a weak link being used, maybe you should consider changing hardware. The Wichard 2673 Quick Release Shackle which is the heart of the most popular of these systems has a rated functional load of 2425 pounds. You can go through a lot of weak links, tow lines, gliders, and tugs with that figure.

I hope that my comments may help to improve on and refine what I consider to be an excellent system.

cc:
Gregg B. McNamee
Luen Miller
Capitol Hang Glider Association list server

(Published: 1997/02)
Tad Eareckson - 1996/12/06

To: Gregg McNamee

comment opportunity

Thanks much for the aerotow bridle article in the current issue. Immediately following this message I'll have wired you a copy of a letter I'm submitting to the editor. Hope I don't get as pissed off with this one as my last one did Kent Harker.

Feel free to fire away with any constructive criticisms you may have.

Best wishes,
Tad
Gregg McNamee - 1996/12/16

Hi Tad,

Thank you for your input.

I agree that those of us that have extensive towing experience need to help the people new to towing from learning the same lessons we have already learned.

Many injuries and accidents brought us (old tow pilots) to the point we are at and I hope we can help the new tow pilots to not repeat the mistakes we have learned from.

Stay in touch,
Gregg
Towing was making great strides forward.
And some catastrophic, lethal great strides backwards.
Center-of-mass bridles were being developed and tested to enhance the pilot's ability to control the glider while under tow.
Center-of-mass bridles were never really tested. If they had been people would've realized that there was no such thing as a center-of-mass bridle.
New releases were being tested on every flight to examine the safest options available.
- It's an astronomically bad idea to "test" a release in flight.
- It's of no value whatsoever anyway to "test" a release in flight.
- Tested on every flight?
- Then how did we end up with the absolute crap we have now?
- Was anybody testing them on the ground?
Many thousands of tows, and years of flying under tow, have taught us techniques to safeguard pilots from some equipment-related problems.
Name ONE THING we learned in the air that we couldn't have on the ground.
Like most pioneers, when someone was hurt or something went wrong, we learned what not to do and what to avoid.
- Who's "we"?
- Did we really need to wait until something went wrong or someone was hurt or killed?
- Frank Sauber, Bill Bennett, and Mike Del Signore were killed within the previous seven month period prior to publication of this article.
- Yeah, right.
In time we arrived at how to do it right...
Yeah, sure we did. So we can stop all advancement now (then).
...and would like to share that information in order to help the towing community avoid some of the accidents...
Accidents?
The time-proven information...
How does time prove anything? If a known defect on a release hasn't killed anyone in the ten years it's been in widespread use does that make it safe? (Got an opinion on that, Robin?)
The Aerotow Release System consists of four components that work together to provide the pilot with enhanced glider control while under tow, and the ability to terminate the tow at the pilot's discretion.
We got anything which gives the pilot the ability to CONTINUE the tow at his discretion? Maybe a tug driver with half a brain or better and a weak link that doesn't blow whenever it gets bored?
The components are the pilot's release, secondary release, bridle and weak link (see Figure 1). Each element in this system is equally important to the safety of the pilot.
- So the secondary release and weak link are as important as the primary release?

http://groups.yahoo.com/group/skysailingtowing/message/4633
Weaklinks and aerotowing (ONLY)
Steve Kroop - 2005/02/10 04:50:59 UTC

Weak links are there to protect the equipment not the glider pilot. Anyone who believes otherwise is setting them selves up for disaster.
- Seems to be some disagreement as to the importance of the weak link as a component relevant to the safety of the pilot.
To actuate the primary release the pilot does not have to give up any control of the glider. Common sense tells us that the last thing we want to do in an emergency situation is give up control of the glider in order to terminate the tow.
- And exactly when was it that common sense started having a role in hang gliding equipment and procedures?
- So you're on the record with saying that the Wallaby Release with a downtube mounted lever is a lunatic piece o' shit?
- So how come that isn't in the specified in the primary release criteria in the USHGA aerotowing regulations?
The inability to release or premature release can have serious consequences for an unsuspecting pilot.
- But a suspecting one is gonna be OK, right?
Dave Broyles - 1990/11

I talked to a lot of pilots at Hobbs, and the consensus was that in the course of Eric Aasletten's accident, had a weak link break occurred instead of the manual or auto release that apparently did occur, the outcome would have been the same. Under the circumstances the one thing that would have given Eric a fighting chance to survive was to have remained on the towline.
- Could a weak link failure have just as serious consequences for a suspecting or unsuspecting pilot as a premature release? (Yeah, I know. If you say anything negative about a light weak link you don't get published.)
The pressure required to actuate the release must not be more than three to five pounds...
Pounds? Or pounds per square inch?
...throughout the entire towline tension range (from zero tension to the maximum strength of the weak link).
But a Bailey Release that requires over four times that maximum at 130 pound Greenspot is OK 'cause, since Bobby designed the Dragonfly, we'll cut him lotsa slack.
If the pressure required to actuate your release increases as the towline tension increases ... you should rule it out as well.
Well, that pretty much eliminates everything except the Linknife, my bungee powered job, and Steve Kinsley's four-string and my variation.
The secondary release is a backup.
No. The secondary release is a secondary release. If you try to use it as a backup you can get killed real quick.
If the primary release fails...
Towing was making great strides forward.
New releases were being tested on every flight to examine the safest options available.
In time we arrived at how to do it right...
The primary release must disconnect the towline from the glider at the pilot's discretion...
But we're still using primary releases that fail? Not sure I'm really following you here.
...or the bridle gets hooked on the towline, you'll be glad you have a secondary release.
Assuming you're still alive at this point.
Some pilots use a hook knife as a "secondary release,"...
No. Total idiots fly with and delude themselves into thinking that a hook knife may have some useful function on tow.
...but I prefer an equestrian emergency release on the shoulder of my bridle. That way, if, after actuating the primary release the bridle becomes entangled with the tow ring, I can use my secondary release to detach from the towline.
So although the secondary release is equal in importance to the primary and a system which requires you to take your hand off the control bar to actuate the release it is not suitable, this system is suitable. OK...
Note in this scenario that the weak link is no longer part of the aerotow release system and it is very important to be able to detach from the towline immediately.
- If the bridle wrapped after the weak link blew during a lockout, the weak link is no longer part of your aerotow release system, the PRESSURE required to actuate the release must not be more than three to five pounds, then how fast do you hafta be to blow your secondary before it's overloaded?

- Have you ever read the regulations for aerotowing which state:
"A weak link must be placed AT BOTH ENDS OF THE *TOW LINE*."? (Just kidding.)

- What's stopping you from protecting the secondary release with a weak link if you're not happy adhering to the regulations?
The secondary release needs to be within reach and sight of the pilot without requiring you to look away from where you are going.
How 'bout just putting an actuator in your teeth so's the secondary can be up to the standards of the primary.
If you use an equestrian emergency release be careful not to get one with such a large collar that when you snatch on the towline the mass of the collar causes an unwanted detachment from the towline.
If that means what I think it does... Wouldn't you actually WANT an unwanted detachment from the towline?
It allows the pilot to change his pitch position relative to the tug...
"Pitch position"?
The bridle also permits the pilot to effortlessly move side to side without having to fight the towline tension, making the ever-useful...
...imaginary...
...flat turn less difficult than with a more restrictive bridle arrangement.
You can see though that this system tows the glider through the pilot, as opposed to older arrangements that towed the glider while the pilot attempted to maintain control.
Which were eradicated about fifteen years ago so why are we even discussing them now?
This bridle also helps keep the glider in position.
Yeah? Ever take your hands off the bar for more than three quarters of a second to test out that little hypothesis?
If the towline tension increases, the pilot's weight is pulled forward, helping him to speed up with less effort.
No it isn't. The glider will pitch up and climb.
If the glider is off to one side, the pilot's weight is pulled to the appropriate side, moving the glider back into position.
No it isn't. The pilot will stay centered while the glider continues to roll away and locks out.
The rope acts as a slide for the loop of the second rope in the system, allowing the pilot side-to-side movement.
And if you connected the bottom of the primary bridle to a three-string fixed at the center / apex of the secondary bridle it would prohibit side-to-side movement?
Do not make the second rope so short that in the slowest flying position...
Doesn't the issue of relative positions of tug and glider dwarf to total insignificance any "issue" of "slowest flying position"?
..the first rope comes to the ring on the towline, or to where the towline ring is close enough to the pilot to hit him if the towline breaks.
- If you use elastic bridle material the tow ring is ALWAYS close enough to put him in the hospital if the towline breaks.
The tow line must be at least twice as strong as the weak link in use.
- There's a REGULATION which requires you to use a towline that doesn't break.
There are no knots in the bridle system so that the rope can slip through the rope loop...
- Slip or burn? Use a goddam thimble.
- Is there any possibility of a SPLICE not making it through? With or without a goddam thimble?
... or the towline ring without restriction.
If the primary release fails or the bridle gets hooked on the towline, you'll be glad you have a secondary release.
If the released end of the secondary bridle somehow - ASTONISHINGLY - fails to clear the "rope loop" at the bottom of the primary bridle, THEN what will I be glad to have? A hook knife? A good health care plan? My affairs in order?
WEAK LINK CRITERIA

The weak link utilized in this system is one loop of 130-pound test Dacron fishing line -- no nicks or frays.
That tells us what weak link is utilized in "THIS" system. It DOESN'T tell us ANYTHING about CRITERIA, what "THIS" system is, the point of failure of that loop, or why it's appropriate (for something other than fishing).
When I started towing, years ago, the tow rope was the weak link, and would literally fail the airframe of the glider if the tow pressure was too high.
- When you started towing, years ago, the gliders were "constructed" out of bamboo, plastic sheeting, and duct tape.

- If the airframe failed before the tow rope then the airframe was the weak link. Dinosaur days towlines were NEVER thought of or used as weak links. Back then they understood how dangerous failures of the equipment between the tow vehicle and glider were.

- I just looked at your website and the towline is STILL the weak link about two thirds of the time that something blows.
I prefer to learn by example rather than practice...
Too bad. The people who know what the hell they're talking about have generally done their learning by well established and rather simple and straightforward theory.
...so I accept no substitute when it comes to weak links.
Yeah! It's almost impossible to find an aerotow park, tug driver, or competition organizer who DOES accept a substitute! You just can't beat a loop of 130 pound test Dacron fishing line for protecting airframes. Twenty years of Dragonfly towing and NOT ONE SINGLE buckled cross spar or snapped leading edge section! AMAZING! Why mess with that kind of success?

And, of course, I also protect my airframe to a similar margin by limiting my airspeed to 28 mph, bank angles to twenty degrees, and flying times to an hour after sunrise and before sunset - so I avoid all that nasty midday thermal turbulence. And I NEVER do the preflight sidewire load test 'cause that stresses the airframe to around TWO Gs! That's the kind of abuse you'd get if you banked the glider to sixty degrees! Totally insane.

And I never put more than twenty hours on a glider before I dump it on some sucker on eBay and buy a new one - just to be extra safe.
As mentioned, the second rope in the bridle system has a spliced loop at each end. One end slides on the first rope...
Yeah, a bit like your knee slides on asphalt after you wipe out on a bike.
The weak link is wrapped around the loop four or five times, then tied twice with a non-slip knot. Any single loop that is NOT immediately adjacent to the knot may be used to connect to the primary release mechanism.
- Assuming that "takes the knot out of the equation" wouldn't that result in a stronger weak link and thus a greater risk of folding up your airframe?

- Have you ever TESTED:
-- that configuration to see if it makes enough difference to be worth talking about?
-- your 130 pound Dacron fishing line loops in ANY configuration?

- I haven't ONCE heard you say ANYTHING about the strength of these loops. Do you have ANY IDEA WHATSOEVER what the strength is? Or are you just using them 'cause everybody else is and you've never blown up a glider using one?

- Has anybody ever explained the G concept to you?
The loop should NEVER be longer than half the diameter of the tow ring it must pass through.
Why should the loop be any longer than what's required to clear the release without resistance?
This would immediately double the tow line tension experienced by the pilot until the weak link broke.
How 'bout the force the pilot may experience as a consequence of slamming into the runway if the weak link DOESN'T break?
If you accidentally used the wrong link, the releases would be trying to work under greater tension (maybe beyond their working range).
But, as discussed above, this isn't an issue with which you need concern yourself if the single weak link at the top of the primary bridle gets taken out of the equation by a wrap.
I hope this information helps prevent those in our towing community from reliving the experiences that have brought us to this point.
And, since you've proclaimed that we now have everything right, will condemn any evolutionary advancement that anybody tries to establish beyond this point.
We just don't live long enough to make all the mistakes ourselves.
Yeah, but don't worry - the flight parks are gonna be there to make sure we keep making the really important ones at pretty frequent intervals.
Gregg McNamee is a USHGA Advanced Tandem Instructor, Aerotow Supervisor, Honorary USHGA Board Member, a Basic Flight Instructor with USUA (U.S. Ultralight Assn.) and owner of GrayBird AirSports, an aerotowing flight center in Florida.
And yet has no working concept of what a weak link is or how to configure it - in accordance with USHGA regulations - to protect the glider at all times.
Tad Eareckson - 1996/12/06
Former(?) instructor and qualified pilot fiend.
Although the issues may be fairly minor...
They're not. I was way too deferential back then.
I think it's fairly safe to say that release configuration and reliability problems were large looming factors which reduced the rosters of the local club by two and of the region by three this past season.
They were in the Frank Sauber scooter tow fatality. There were also huge issues with the releases in the Bill Bennett / Mike Del Signore tandem aerotow fatality which could easily have killed the tug driver as well, but they had no bearing on the actual outcome.
It's also not a bad idea to use a thimble in the splice in the primary bridle through which the shoulder-to-shoulder bridle is threaded to reduce friction and wear.
Use the goddam thimble - not an option.
To address Don Hewett's concern about the danger of this threaded system jamming at low altitude...
That evil was mostly imaginary and never held a candle to the evils of the Skyting ASSUMPTIONS.
...minimized by using a heavier, stiffer material than is sometimes seen...
...used, and sold by assholes like Davis...
...and ensuring that smooth splices are used in both ends.
The smooth splices don't do the trick - it's the increased stiffness and mass of the splices that are the main problems.
Although the practical risk may be so small as to hardly be worthy of mention, there is a hypothetical possibility of the secondary release described in Gregg's article failing in precisely the manner of the above concern.
Bullshit. It's a real threat, it happens in real life, it's not acceptable to configure on the assumption that that's not a possibility.
The secondary release incorporated in my system is a leech line Lark's Head with Toggle (check a knot book), the toggle being a tiny cotter pin with a short lanyard attached, everything safetied with a light wrap of masking tape.
The leechline (205 Dacron) body of that little assembly was also my secondary weak link (probably shoulda made that clear). That was a really good thing.

The secondary release mechanism itself the worst idea I ever put into the air. It worked great under a bit of hand generated tension - totally froze in the ballpark of the real thing. Fortunately I was on the ground when I had the crap scared out of me. Left a lifelong reminder that NOTHING could EVER go into the air without proper bench testing. The good news was that the Bailey had been out for five years by that time so the public already had a secondary which would lock up under load and ignored my comments to same the extent it always has.
Also note that this secondary link may make the effects of the snagging of a trailed primary bridle (the potential for which is illustrated on the December issue's cover)...
Terry Reynolds coming in for a landing at Wallaby Ranch in an Acme "Topless" TR3. Photo by David Glover.
The Wichard 2673 Quick Release Shackle which is the heart of the most popular of these systems has a rated functional load of 2425 pounds. You can go through a lot of weak links, tow lines, gliders, and tugs with that figure.
Actually... Back then I ASSUMED that by "functional" Wichard meant that it would FUNCTION as a "quick release" at eleven hundred kilograms. Good freakin' luck. It's FUNCTIONAL as a SHACKLE at that loading but not as a quick - or slow - release until you get down to something adequate for hang gliders but not much more.
I hope that my comments may help to improve on and refine what I consider to be an excellent system.
Yeah, sure. It was another eight years before the next flight park or person would even bother putting another weak link below the tow ring.
Stay in touch,
Gregg
Well Gregg, we didn't stay in touch but it doesn't look like you addressed, incorporated, or helped me with ANY of my issues.

You get a lot of brownie points for emphasizing that it's a really bad idea to take a hand off the basetube in a lockout but the vast majority of aerotows still go up with Bailey releases and levers on downtubes.

You're still using a 130 pound Greenspot weak link, polypro bridles, a jam prone secondary bridle, and a panic snap on a shoulder.

You're not using secondary weak links, a thimble, or dual shoulder releases.

And I never heard you advise people to turn their carabiners back around to the way the parachute manufacturers envisioned things when they were deciding on the safest anchor point for the bridle.

So what possible point would there have been?
User avatar
Tad Eareckson
Posts: 9150
Joined: 2010/11/25 03:48:55 UTC

Re: instructors and other qualified pilot fiends

Post by Tad Eareckson »

http://www.ushawks.org/forum/viewtopic.php?f=2&t=674
Nate's minor accident at Packsaddle
2011/07/03 15:56:14 UTC
http://groups.yahoo.com/group/hhpa/message/13162
B Asher

Nate (Wreyford) got high again, went back to the air port again, but this time did not make it back.

He got caught in the North Pack rotor, had a safe landing off the NE corner of the hill. Ate a good size live oak, and took out his left leading edge. O-well, it was almost a perfect day. He was not injured, but fixing that Carbon Graphite peace may be expensive.
This is absolutely TERRIBLE news. (And I'd been doing so well with Hugh and Sparky earlier this season.)
Everybody remember to take his glider off the ramp with him this round?
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