bridles

General discussion about the sport of hang gliding
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Tad Eareckson
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Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Jay Z - 2020/09/22 20:17:45 UTC

As a foot-launcher, I don't understand this.
Nah, there's no fuckin' way you could possibly understand this as a foot-launch. Even if you foot launched behind a tug minus the dolly it would be way too incomprehensible.
The glider actually climbs better with the VG off?
The glider climbs really well when:
- it's being towed through a line way the hell below its centers of mass and drag
- the control bar is trimmed to the knees of the glider pilot when the tug gets safely above its stall speed
Aaron Swepston - 2020/09/23 03:42:13 UTC

I've never seen anything like this before. Single surface gliders with totally baggy sails, intermediate gliders, high performance gliders, all able to tow without VG on.
Show me some videos of single surface gliders with totally baggy sails, intermediate gliders flying pro toad.
What does look weird to me is that it appears that your body is tilted somewhat upright, with your arms pushed down instead of back, where instead of pulling in, you're pushing your shoulders up. I don't know if that is what is happening here, but I have seen SO many people do a sort of pushup on the basetube thinking they were pulling in for speed, when in fact they were mostly just rotating their body upright with not all that much forward weight shift occurring, and as a consequence not a lot of speed or acceleration.

It could be an illusion due to the camera lens and the angle of view, but consider also that with the trike below you, and the camera behind you, it would seem that the camera should not see so much of your back, that your body should be angled in line between the camera and the tug, with your front end aimed at the tug, not up towards the nose of the glider. Perhaps you were hanging too high as well? That also exaggerates the above "pushup" situation.
Stellar analysis, Aaron. I missed all that.
Leading Edge - 2020/09/23 12:14:21 UTC

Without seeing the attachment point (to the pilot) or the harness position, we are missing information.
We're also missing the attachment point (to the glider) or the keel position - idiot.
As an almost exclusively AT pilot, it looks to me like he is towing far too head up.
And it looks to me like you're writing far too head up ass.
That harness should be rocket downward.
I guess that harness would be rocket upward if the glider were hit by a monster thermal - the way Zack Marzec's was long ago at Quest - where they kept on doing things the same expecting better results and only killed one airline pilot in the years since.
If not, you get the head-up, push-up action like you see there.
Get fucked.
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Tad Eareckson
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Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=63584
Release before getting too high behind the trike
Davis Straub - 2020/09/23 14:06:17 UTC

You could flip him over
Jim Prahl - 2020/09/23 14:06:17 UTC

Climbing high on the tug is dangerous to the tow pilot. Better for the hang glider pilot to hit the release. The weaklink may not break.

If the tow pilot for some reason cannot release the glider pilot, the tug might get flipped over. It's good that it worked out well this time.
JD Guillemette - 2020/09/23 22:31:47 UTC

Jim,
I understand the issue with the glider getting high on Dragonfly, but does this also apply to a trike?
Davis Straub - 2020/09/23 14:06:17 UTC

You could flip him over
WHOA! I never thought of that! It sure is a good thing we have Jim Prahl phoning in to help with this critical AT safety issue. Pity he was out sick when all us muppets were trying to get a grasp on what happened on the Zack Marzec and Jeff Bohl Quest inconvenience fatalities.
Jim Prahl - 2020/09/23 14:06:17 UTC

Climbing high on the tug is dangerous to the tow pilot.
GOOD.
Better for the hang glider pilot to hit the release.
The easily reachable pro toad release which has never presented the slightest issue for anybody.
The weaklink may not break.
- Malcolm assures us otherwise.
- Only if they're stupid enough to be using Tad-O-Links.
If the tow pilot for some reason cannot release the glider pilot...
Any thought on some reasons glider pilots can't release tow pilots?
...the tug might get flipped over.
FLIPPED OVER. In the entire history of aerotowing - conventional and hang gliders - is there a single documented incident of a tug being FLIPPED OVER?
It's good that it worked out well this time.
It didn't work out well. An AT goes up in nothing conditions, the glider has to keep the bar stuffed from the word go and is at eighty feet while the tug's still on the runway, the weak link blows, and all we're talking about is how the VG cord got kicked out of its cleat.
JD Guillemette - 2020/09/23 22:31:47 UTC

Jim,
I understand the issue with the glider getting high on Dragonfly, but does this also apply to a trike?
- Aren't you gonna thank him again for that daring test flight me made early 2008 to find out once and for all whether or not a glider could be safely pro towed with a keel-only connection?

By the way... Having trouble keeping the glider down to or below tug level? This is the guy with whom you really wanna be consulting. (Asshole.)

- No, think about it. A tow trike is just the same as the hang glider behind it - weight shift controlled wing 'cept with an engine and takeoff/landing gear below it too.

http://ozreport.com/forum/viewtopic.php?t=9230
Departing the launch cart
Jim Rooney - 2007/08/24 12:20:06 UTC

Bad habit #1, not flying the glider... just letting the tug drag you around by the nose, combines with the fact that pro towing REQUIRES the pilot to do something (not let that bar move). So instead of holding the bar where it is, bad habit pilot just lets the tug pull him. This pulls him through the control frame with the same effect as the pilot pulling in... a LOT.

I've seen gliders go negative while still on the cart this way.
The results are never pretty.
When you're high like Oliver was you're swinging the pilot pendulum back and up under the center aft area of the wing. That's exactly what you do for a perfectly timed landing flare.

15-3703
http://farm4.staticflickr.com/3677/14267100052_9ba5bb5bdc_o.png
Image

So it's actually nosing the trike UP. Kinda counterintuitive but, hell, what is there about hang gliding that isn't? In conventional aerotowing they have towline TENSION ferchrisake.

See?:

15-2928
http://live.staticflickr.com/65535/50376674553_0a1d9b538c_o.png
Image

He's doing fine. He's actually needing to pull in a fair bit to keep from getting stalled.

(Where's Jim Keen-Intellect Rooney when ya really need him? He's so much better explaining stuff like this than I'll ever hope to be.)
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Tad Eareckson
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Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Oliver Moffatt - 2020/09/24 14:22:57 UTC

Letting the VG off slackens the wing which allows more twist to develop. This reduces the lift generated at the tips, which moves the centre of lift forward, which means the nose is lifting more. I don't know whether the wing produces more lift, but it is distributed differently.
- Wow! You're really good at explaining how all these aerodynamic forces work on these wings, Oliver. Most impressive.
- Here's another way to say it... A tight flat wing generates lift more efficiently than a loose twisted wing.
Oliver Moffatt - 2020/09/24 14:29:29 UTC

Excellent and experienced aerotow pilots I have spoken to, including multiple British champions and the UK Moyes importer, tell me that 1/3 to 1/2 VG is essential for a normal-weight pilot on an RX...
Fuck the excellent and experienced aerotow pilots - including the multiple British champions and the Moyes importer you've spoken to. Same useless fuckin' idiots and douchebags we have over here and in Australia.
...with more VG possibly required for a pilot lighter in the weight range.
Jesus H. Christ. Trim the fuckin' glider.
I am light on this glider and I typically use just over 1/2 VG, which works very well.
As does your BHPA AT weak link.
I brace for the tow with my body as low as possible and I would have noticed if I was not in the proper position.
Nah, you were in GREAT position. When you're with just one attachment point it pays off bigtime to have it as low as possible.
The harness is a butt-lever type and you can see that the boot fabric is tight, showing that the slider rope is also tight and hence the slider is in the rearmost position.
Sounds complicated - more chances for something to go wrong. Better...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2871
speed link
JD Guillemette - 2008/02/07 12:51:57 UTC

Now that I think of it, I'm not sure where I got my "Bailey" releases. I don't think any of them have the rivet. I think the first one that I still have on my I-Tracer harness was given to me by my first Aero-tow instructor. The other two were on my Rotor harness when I bought the harness used. I just assumed that they were Genuine Bailey Releases, but without the rivet they must be imitations.

Although I have not seen a genuine Bailey release, it would seem to me that a rivet is a better solution to the problem, especially when curved pins are used. Bobby Bailey's designs have always impressed me, simple, elegant, and effective designs. It is no surprise to me that Bobby had already resolved the issue.

For these same reasons, It just bothers me when people try to "improve" upon Bobby Bailey's designs ... simply put, the designs are at the maximum of efficiency and safety. So I'm right back to where I was. I see no problem in the way things are currently done and creating overly complicated mouth actuated releases is just a waste of time.
http://ozreport.com/forum/viewtopic.php?t=14903
New Lookout Release--preliminary test
JD Guillemette - 2009/02/13 03:24:15 UTC

Sweeeet!!!! Looks good to me.
I like the bent gate bar, as Marc suggested that should make release force many times less than tow force, if not nearly independant of tow line force.
Nicely done Lookout! Elegant solution!
As in most cases, the simplest designs work best.
...stay with one point.
Oliver Moffatt - 2020/09/24 14:34:10 UTC

Thanks for your comments, and to Davis for posting it here :D
Yeah, ain't Davis and the Oz boys just the best.
I've towed this glider and tug combination several times very successfully. The only thing different this time was the VG setting. I am sure that this was the cause of the problem.
Alright then. You got that fixed so now you're bulletproof.
I promise to come back here and submit myself to a verbal lashing if I am proved wrong :lol:
Don't worry. Davis will keep things pretty safe and civilized over there.
Martin Henry - 2020/09/24 15:26:02 UTC

No question, if I was the tug pilot (trike or Dragon) you would be the proud new owner of a tow line ;)
If I were the tug pilot that tow configuration wouldn't have been hooked up behind me in the first place.
A good example of how even our sailplane buddies are not immune to this sort of high risk situation...
If our sailplane buddies were worth shit they'd have stepped in decades ago and denounced the shit that's going on with hang glider AT since the beginning of time.
A few years back at a busy Washington state sailplane operation, a glider being towed let his spoilers pop open at the start of the tow (they were not in the lock detent).

The tug pilot spotted the issue (and obviously felt it), and radioed back to get the spoilers closed. The glider pilot slammed them shut but did not anticipate the massive increase in lift, ballooned extremely high in the tow position, this lifted the tail of the tug up, leaving the tug pointed at the runway in a very low altitude at a low attitude with full power. The rope broke or somebody hit the release and tug flew steeply into the runway and the pilot was killed.
1. So they weren't flying with dedicated weak links?
2. So the glider rocketed up so fast that the tug couldn't react quickly enough to reduce power? Having a hard time buying this.
Like I said, You get that far out of the tow "box", its your rope and your problem.
All he did wrong was not ensure that his VG would stay cleated and that translates to a life threatening incident? The VG comes loose five seconds into the roll and we have a serious situation on our hands? Our safety margins are that razor thin?
Like most bad towing incidents, somebody fails to release soon enough and things go bad... very quickly.
Weren't there TWO somebodies who failed to release soon enough? And the one about whom you're so concerned was almost certainly the more experienced and qualified pilot. And where do you think you probably stack up against him?
BTW, not a lecture on the incident, thankfully a lesson learned?
Yeah Martin. Another lesson learned. Thankfully. With all these lessons we keep learning the sport's just getting better and better all the time.

And here's an earlier version of your presentation.:

http://ozreport.com/forum/viewtopic.php?t=15716
weak links
Martin Henry - 2009/04/26 16:23:56 UTC

Tad,

Its astonishing how manage to take a simple short little piece of string and stretch it into an 11 page (and still going) thread ;)

Like George says, your posts are getting better and there is some actual "content" , still, for some strange reason I can't help but click on your posts once in a while, like putting on some Abba tunes and never admitting I liked the music...

The reason I thought I would post is, well your very caught up in your end of the towline you seemed to be in a bit of a battle with the guy (or gal?) on the other end of the line. I have absolutely no challenge to your 1.4 mass weak link (Mainly because there is only so much time I can dedicate to string...) but... If the guy on the front end of the line does not like it, then I think you should respect their side of the argument?

Trike Tug pilots (most), Bailey Tugs with the smaller two strokes or anything that is simply underpowered have a pretty small margin of safety when it comes to the towing envelope. It's a complicated balance. I've heard the expression, "it's like flying two aircraft at once". Getting your tail hauled up, down, left and right buy less then cooperative customer can be down right nerve wracking. If your tug pilot wants you on a "weak" link, you should respect his wishes. If you don't like it, find a tug pilot that can handle the challenge. If he's a lousy tug pilot, he will sooner or later be out of business, If he's good, pilots will line up to be towed. My point there are two aircraft involved. If your being towed up by a big 914T your tug pilot might be able to muscle his way out of a problem, but if he's driving a wheeze two stroke he simply may not have the power to put up with much trouble caused by a strong weak link.

For a sad example of what can happen to a tug when things go wrong...

In Washington State a few years back a Sailplane operation had Tug go down. During the roll, the Spoilers "popped" open on the two seater sailplane (with student at the controls). The Tug pilot sensed a problem as the tow progressed... things where simply not happening as they should. He glanced back and saw the spoilers open. He should have given the glider the rope. He didn't, he powered hard into the tow and got on the radio and screamed at the student to get his spoilers closed. There was plenty of energy building and the student realized his error and slammed the spoilers shut. The glider, now with speed, ballooned rapidly and the student did not react fast enough to compensate, shooting way too high. The high tow position, Tug at full power (trying to power his way out of the problem) the glider was pitching the tug down. The rope/weak link failed. The Tug still low to the ground at full power, close to stall, nose down, drove straight into the rough ground off the end of the runway and the Tug pilot was killed.

Flying a Tug with a heavy customer at the end of the towline is a ballet dance with a fat lady, you have to do it right or somebody could get killed.

Now its back to my "Abba's Greatest Hits"...

Cheers
Martin
And my responses...
Tad Eareckson - 2009/04/26 20:05:29 UTC

Martin,

That short little piece of string (which - in my opinion - should not even be a short little piece of string) can/has/will kill people when it breaks at the wrong time, causes total havoc in flight operations, and is virtually NEVER required for the safety of a flight. (Notice the total dearth of posts from people with evidence to the contrary?)
I have absolutely no challenge to your 1.4 mass weak link...
It's not mine. This is pretty much an aviation standard outside of the inbred little world of hang gliding.
If the guy on the front end of the line does not like it, then I think you should respect their side of the argument?
I generally find that virtually no one in the sport on EITHER end of the line has enough of clue about the purpose of a weak link to BEGIN to present a hint of a side of a rational argument. The vast majority don't even have a clue as to the breaking strengths of what they're using or how these strengths translate to tow line tension.
If your tug pilot wants you on a "weak" link, you should respect his wishes.
Sorry but - BULLSHIT. USHPA defines a safe upper limit of two Gs but was too stupid to define a lower end at which things become dangerous. I SAY anything much south of 1.4 is DANGEROUS to me and it's his job to make sure I don't get stuck with the rope in the event that things get really far outta hand - which ain't never gonna happen anyway.
If you assume that the tug's release is rusted shut the back end bozos who can't get to their releases are the ones who present the biggest threat to both planes - but we never hear much about them 'cause majority tends to trump common sense.
In Washington State...and the Tug pilot was killed.
And this is pertinent to the discussion HOW?
In Washington State the planes are REQUIRED under federal law to be connected with a line and/or weak links which hold to a MINIMUM of 0.8 Gs. The part of your paragraph giving any indication that this situation either progressed above that tension or needed to in order to achieve the end result is completely absent.
The tug was killed, not as a consequence of anything above what needed to be and probably was only minimal tension, but as a consequence of how far out of position the sailplane was and how quickly it got there. If the rope was strong enough to get the sailplane aloft at all - it was also strong enough to let the glider kill the tug.
Now to this part of the paragraph...
He should have given the glider the rope.
Once again with emphasis...
HE SHOULD HAVE GIVEN THE FREAKIN' GLIDER THE FREAKIN' ROPE.
but...
He didn't...
http://www.dynamicflight.com.au/WeakLinks.html
In all aviation the pilot is usually the weakest link...
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. The pilot activating his or her releases is their way to save themselves.
In sailplaning it's ALWAYS the tug that gets killed and NEVER the glider.
In hang gliding it's just the opposite 'cause the Dragonfly's control authority blows the glider's away and the latter can't get out of position fast enough to do any real damage.
Flying a Tug with a heavy customer at the end of the towline...
I'm NOT a heavy customer - I'm two hundred pounds under some of their tandems.
Take a chance on me...
Tad Eareckson - 2009/04/26 22:26:11 UTC

Martin,
Lemme try this...
You said the sailplane was a two seater. I don't know what it weighed but let's be ridiculously generous for the sake of his argument, make it a single seater, and say that it and its occupant total 500 pounds.
We'll put a minimum legal weak link on its end of the towline - 0.8 Gs - 400 pounds.
Let's screw the same pooches so he ends up rocketing over the tug's tail but still the weak link is only being stressed to three quarters of its capacity.
He's pulling STRAIGHT UP with 300 POUNDS on the END OF THE TUG'S TAIL. You wanna sell him insurance at this point or do you think he has a pre-existing condition?
Let's run the same drill with a Dragonfly and a little chick who weighs - with her glider - 200 pounds.
She's flying one point and using a single loop of fuzzy Greenspot which we'll call 100 pounds.
She can pull straight up on the tail of the Dragonfly with 200 pounds. Ya think she can't develop sufficient tension to plow him back into the runway?
Thanks for sharing
And you never responded to my responses. And Davis locked the thread 2009/04/28 12:45:14 UTC 'cause I was kicking Flight Park Mafia ass. And that's what Davis ALWAYS does whenever that happens.

And back then it was ALL about weak links. And this time there's NO MENTION of weak links - even though it was a BHPA weak link that defused this lethal situation of which the tug pilot was totally unaware.

http://groups.yahoo.com/group/skysailingtowing/message/7230
Towing question
Martin Henry - 2009/06/26 06:06:59 UTC

PS... you got to be careful mentioning weak link strengths around the forum, it can spark a civil war ;-)
Yeah, be very careful mentioning weak link strengths around the forum - that one that, like its total douchebag owner, no longer exists or this one where nobody ever heard of a weak link before.
Oliver Moffatt - 2020/09/24 19:28:39 UTC

Totally agree, Martin.
Really hard to go wrong totally agreeing with Martin on anything. Just be sure to keep current on his posts so you know what latest positions are.
I should have dumped the rope sooner.
Oh. You need to hear this from Martin. But the guy on the front end of your rope strangely had nothing to say regarding this extremely serious incident that could've easily totaled him.
I've been thinking about that aspect.
Why? You weren't briefed on a situation like this while getting your AT rating 'cause none of your instructors considered such a total douchebag situation to be a reasonable scenario?
I suspect that because I had successfully regained position in the past, I assumed I would do so again, and at that time I didn't realise anything was set wrong.
- Successfully regained position from WHERE in the past and flying what glider with what bridle? You didn't go up pro toad on your first half dozen flights.

- Oh. That's in the owner's manual? They tell you where to set your VG for pro toad AT safety and you did but slipped and suddenly two planes were critically endangered?
So I delayed, and the weak link saved my bacon.
Fuck yeah. They're great at that, aren't they? Succeeded just in the nick of time. God only knows what might have happened...
Oliver Moffatt - 2020/09/22 04:23:59 UTC

I had a useful lesson on Saturday. Coming off the trolley, I immediately climbed above the tug, and continued to climb until the weak link broke when I was about to release.
...otherwise. Just think what might have happened if you'd been using a weak link calibrated for a glider thirty pounds heavier than you are.
Next time, I'll be out of there. Yes, lesson learned.
Good thing we have The Davis Show out there for us. At The Jack Show...

http://www.hanggliding.org/wiki/HG_ORG_Mission_Statement
HG ORG Mission Statement - Hang Gliding Wiki
* When posting, think about non-HG pilots who come to visit the site every day. Please put your best foot forward and showcase the fun adventurous atmosphere we experience every day in the landing zone after a great flight.
...our local coffee shop owner doesn't permit you to discuss stuff like this. Maybe also check out The Bob Show. Bob has very little experience towing but Bill Cummings is the best of the best on this aspect of the game.
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Tad Eareckson
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Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Steve Pearson - 2020/09/24 22:19:57 UTC

1/2 VG is recommended for aerotowing all Wills Wing gliders configured with VG systems. Towing at less that 50% VG is more difficult because the pitch pressure can be excessively high and that in turn contributes to PIO.
Yeah?

http://1.bp.blogspot.com/-2lk6hbjuJ-c/Ujh-ENPLQrI/AAAAAAAA3IQ/vh46chqQX4M/s1600/JRS_0542.JPG
Image

And here I was thinking that Wills Wing gliders weren't designed to be motorized, tethered, or towed. So then why are you making recommendations on HOW to tow them instead of going back to the fuckin' drawing board and designing them so the CAN BE safely towed?

And what's recommended for aerotowing all Wills Wing gliders configured with VG systems in the way of an upper bridle connection? What did you do? Watch which way the wind was blowing and decide to jump on board the...

http://www.hanggliding.org/viewtopic.php?t=22233
Looking for pro-tow release
Zack C - 2011/06/16 03:14:35 UTC

I've never aerotowed pilot-only but it is my understanding that this configuration pulls the pilot forward significantly, limiting the amount he can pull in further.
Davis Straub - 2011/06/16 05:11:44 UTC

Incorrect understanding.
...incorrect understanding bandwagon?

Go to any sailplane manufacturer and pick a model and he'll tell you what Tost weak link to use. Go to Wills Wing and no matter what model you choose the weak link that goes with it is an "appropriate" one. And an appropriate one is whatever Davis and many of us happen to be happy with at any given moment.

And how come you're posting on a total piece o' shit forum controlled by a total piece o' shit "moderator"?

Go ahead, knock yourself out. I wouldn't click you in over here with a gun to my head and I don't give a rat's ass how many really hot gliders you've designed and produced. That was only part of the job. They're worth less than shit if they can't be safely preflighted, launched, towed, landed.

And don't tell me your gliders aren't designed to be towed 'cause you're posting on Davis's rag and Davis hasn't launched a glider without a Dragonfly in front of him since the beginning of time. And you're weighing in on an AT topic.

And I don't think you've ever posted on The Jack Show. And our local coffee shop owner had no fuckin' clew which way to point a glider in relation to a tug.

Probably a real good bet that most of the people killed on gliders in North America have been killed on Wills Wing gliders 'cause that's what's in circulation. When was the last time one of you guys had a relevant word to contribute to a discussion - regardless of the manufacturer or whether or not there were any relevant design issues?
Towing at less that 50% VG is more difficult because the pitch pressure can be excessively high and that in turn contributes to PIO.
On 2005/05/29 Holly Korzilius gets two thirds killed oscillating until her tug pilot makes a good decision in the interest of her safety - also his 'cause he was a second and a half from certain death - at major Wills Wing affiliate Blue Sky Hang Gliding in Virginia. It's one hundred percent about her having eliminated her two point bridle and both the front and back end weak links and there was zero mention of VG and comment from Wills Wing.

On 2020/09/19 Oliver Moffatt goes up pro toad in Scotland; has his VG slip off; climbs up fast and high but straight as a rail and with the tug just getting airborne, totally unfazed, possibly unaware; has his Infallible BHPA Weak Link increase the safety of the towing operation two seconds before he's gonna make the easy slap to his Koch release; lands in the Balado Happy Acres putting green with a perfectly timed flare, nary a grass stain for the worse... Steve Pearson emerges from the phone booth. Zero percent about being pro toad, no mention of weak link strength. Use half VG 'cause otherwise you might oscillate - which, amazingly, he didn't.

Keep up the great work, Steve.

KSNV-CNN-1-1916
http://c2.staticflickr.com/6/5788/23461251751_e98b9c7500_o.png
Image
WESH2-05
http://c2.staticflickr.com/8/7077/27082298482_cda1aba01b_o.png
Image

Hang gliding has barely scratched the surface in providing solutions for fictional problems while making the actual ones SOP.
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Tad Eareckson
Posts: 9149
Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=15716
weak links
Martin Henry - 2009/04/26 16:23:56 UTC

Tad,

Its astonishing how manage to take a simple short little piece of string and stretch it into an 11 page (and still going) thread ;)

Like George says, your posts are getting better and there is some actual "content" , still, for some strange reason I can't help but click on your posts once in a while, like putting on some Abba tunes and never admitting I liked the music...

The reason I thought I would post is, well your very caught up in your end of the towline you seemed to be in a bit of a battle with the guy (or gal?) on the other end of the line. I have absolutely no challenge to your 1.4 mass weak link (Mainly because there is only so much time I can dedicate to string...) but... If the guy on the front end of the line does not like it, then I think you should respect their side of the argument?

Trike Tug pilots (most), Bailey Tugs with the smaller two strokes or anything that is simply underpowered have a pretty small margin of safety when it comes to the towing envelope. It's a complicated balance. I've heard the expression, "it's like flying two aircraft at once". Getting your tail hauled up, down, left and right buy less then cooperative customer can be down right nerve wracking. If your tug pilot wants you on a "weak" link, you should respect his wishes. If you don't like it, find a tug pilot that can handle the challenge. If he's a lousy tug pilot, he will sooner or later be out of business, If he's good, pilots will line up to be towed. My point there are two aircraft involved. If your being towed up by a big 914T your tug pilot might be able to muscle his way out of a problem, but if he's driving a wheeze two stroke he simply may not have the power to put up with much trouble caused by a strong weak link.

For a sad example of what can happen to a tug when things go wrong...

In Washington State a few years back a Sailplane operation had Tug go down. During the roll, the Spoilers "popped" open on the two seater sailplane (with student at the controls). The Tug pilot sensed a problem as the tow progressed... things where simply not happening as they should. He glanced back and saw the spoilers open. He should have given the glider the rope. He didn't, he powered hard into the tow and got on the radio and screamed at the student to get his spoilers closed. There was plenty of energy building and the student realized his error and slammed the spoilers shut. The glider, now with speed, ballooned rapidly and the student did not react fast enough to compensate, shooting way too high. The high tow position, Tug at full power (trying to power his way out of the problem) the glider was pitching the tug down. The rope/weak link failed. The Tug still low to the ground at full power, close to stall, nose down, drove straight into the rough ground off the end of the runway and the Tug pilot was killed.

Flying a Tug with a heavy customer at the end of the towline is a ballet dance with a fat lady, you have to do it right or somebody could get killed.

Now its back to my "Abba's Greatest Hits"...

Cheers
Martin
Tad,

Its astonishing how manage to take a simple short little piece of string and stretch it into an 11 page (and still going) thread ;)
- Still going, Martin. Eleven years and five months later. 1826 posts here in the topic. And can you cite any figures from hang glider aerotowing from anywhere on the planet that aren't based on track records and opinions?

- Ya know what's even more amazing? That just short of four decades ago Donnell Hewett could pull his Infallible Weak Link snake oil totally out of his ass and send the sport down a path of death and destruction that it will NEVER fully leave.
Like George says...
Fuck George. Name one thing that asshole has ever done to help nudge the sport in a positive direction. What was he doing during the Zack Marzec postmortem discussions? What's he doing now?
...your posts are getting better and there is some actual "content" ,...
Yeah, that must be why the Industry suddenly stopped using actual numbers after the Zack Marzec inconvenience fatality.
...still, for some strange reason I can't help but click on your posts once in a while, like putting on some Abba tunes and never admitting I liked the music...
How do you feel they'd stack up against the posts on the issue we're currently seeing from Davis, Rooney, Ryan, Bart, Jack, Paul, Lauren, Pagen, Malcolm, Russell, Trisa...
The reason I thought I would post is, well your very caught up in your end of the towline...
Yeah. That's the one I'm paying for. That's why the towline exists. If I don't pay for it the Dragonfly gets sold off cheap to a cattle rancher. Well, maybe they can keep going for a while solely on tandem thrill rides... But how's that been working out for the sport lately?
...you seemed to be in a bit of a battle with the guy (or gal?) on the other end of the line.
- The guys (and gals) on the other end of the line are pretty much all stupid incompetent total douchebags.

- Go fuck yourself. On a competent aerotow there's a flight plan, there are two pilots doing everything possible to execute it as safely and efficiently as possible, and equipment, procedures, decisions, reactions, that benefit one also benefit the other. 2016/05/21 Jeff Bohl / April Mackin was a total shitrigged operation and the glider was doomed by one tiny mistake just off the cart on top of all the other crap. But both drivers were totally on the same page to keep the glider airborne to the last second the situation could be sustained. There were Tad-O-Links on both ends that didn't break when they were supposed to and not one single motherfucker on the planet ever breathed a word about dumbing either one down half an ounce.
I have absolutely no challenge to your 1.4 mass weak link (Mainly because there is only so much time I can dedicate to string...)
Zack Marzec - at age 27 - dedicated the rest of his life to his. So why don't you tell us about some of the stuff to which you're dedicating your time and how much good it's been doing?
...but... If the guy on the front end of the line does not like it, then I think you should respect their side of the argument?
- Fuck the guy on the front end of the line.

- What "argument"? Quote me something from one of these motherfuckers that makes any actual sense, preferably something that complies with the FAA AT regs that started covering us - with dissent from NO ONE - the better part of five years prior to this discussion.
Trike Tug pilots (most), Bailey Tugs with the smaller two strokes or anything that is simply underpowered...
Underpowered? So you're saying that it's dangerous to use these things for AT?

http://www.sonomawings.com/archive/fl2003/florida.htm
Vince Endter - 2003/04/12

There were pilots constantly sinking out and landing back at Quest. I landed and got in line again. The third time I was behind a trike that seemed very under-powered or we were in constant sink. They took me over to the west above a swamp, lake and trees. There was nowhere to land if the weak link broke. I looked at my altimeter and I was at 230'. I had set it for 130 before takeoff. You do the math. We continued to fly over unlandable terrain for a couple of minutes before we started any type of climb.
http://ozreport.com/forum/viewtopic.php?t=9230
Departing the launch cart
Jim Rooney - 2007/09/01 02:39:53 UTC

Which brings us to the reason to have a 914 in the first place... you need one.
Something made you get a 914 instead of a 582. 914s are horribly expensive to own and maintain. If you own one, you need it... it's a safety thing. Short runways, tall trees, whatever. You've got a 914 to increase your safety margin.
Yeah, I think we can find some reasonable degree of agreement, common ground on that one. So if it's dangerous for an aircraft to be underpowered on what's supposed to be a powered phase of flight what prediction can we make about the status of the string powered plane when its power is instantaneously chopped from over two hundred to zero pounds of thrust at whatever the hell attitude and altitude?

And while you're thinking about it... Here's an example of the sorta thing that can happen to the front end plane in nothing conditions:

Image
...have a pretty small margin of safety when it comes to the towing envelope.
But don't worry... The glider will always be perfectly fine. He always has the option of blowing his easily reachable release and returning himself to the superior safety of free flight.
It's a complicated balance.
EXTREMELY complicated. That's why we hafta go by individual opinions, experience, track record lengths, invented and flexible breaking strengths rather than using any actual numbers.
I've heard the expression, "it's like flying two aircraft at once".
- I've heard the expression:

http://www.wallaby.com/aerotow_primer.php
Aerotow Primer for Experienced Pilots
The Wallaby Ranch Aerotowing Primer for Experienced Pilots - 2020/09/25

A weak link connects the V-pull to the release, providing a safe limit on the tow force. If you fail to maintain the correct tow position (centered, with the wheels of the tug on the horizon), the weak link will break before you can get into too much trouble.
from the same assholes.

- Bullshit. It's ALWAYS the GLIDER that gets killed when things go south or the driver fixes whatever's going on back there by giving us the rope. His airspeed goes up. We STALL.
Getting your tail hauled up, down, left and right buy less then cooperative customer can be down right nerve wracking.
What a total load o' crap.

- You show me a video of this uncooperative customer. Find me something worse than this:

http://www.youtube.com/watch?v=pC1yrdDV4sI


new Two sorta guy who's been thrown in a bit over his head and never fazes the tug in the least anyway. AT for the glider is unstable as hell. If the air's doing anything you're making constant mini-corrections. After four or five tows max for a 2.5 everybody's an expert. If somebody's hauling a tail left he won't be around long enough to haul it back right. This is EXACTLY what we see at the end of the tow in this one-of-a-kind video.

- Thermal turbulence... Tough shit. That's the only reason we're there and he exists. Deal with it. And if you use some piece a shit Rooney Link to keep you from getting uncomfortable you have to do it TWICE.
If your tug pilot wants you on a "weak" link, you should respect his wishes.
I don't. I have nothing but the utmost contempt for these incompetent assholes and their wishes. I don't do WISHES. I do SOPs established by COMPETENT PILOTS. If some asshole is going up based on wishes I don't wanna be behind him.
If you don't like it, find a tug pilot that can handle the challenge.
Where? Ridgely's tug pilots couldn't handle it and they went totally permanently extinct. Killed two tug pilots and their 914's and neither of them had gliders behind them when they went down.
If he's a lousy tug pilot, he will sooner or later be out of business...
They were - collectively - and they went out of business and existence. So did Finger Lakes, Cloud 9, and, for all intents and purposes, Blue Sky. (Probably weren't using enough fins.) And when these places go down hang gliding activities in their areas take huge hits.
If he's good, pilots will line up to be towed.
Suck my dick. Pilots line up and take the next available tug. How do things work on your planet?
My point there are two aircraft involved.
I don't give a rat's ass what your point is. You're full o' shit. Davis wouldn't tolerate you on his wire if you weren't.
If your being towed up by a big 914T your tug pilot might be able to muscle his way out of a problem, but if he's driving a wheeze two stroke he simply may not have the power to put up with much trouble caused by a strong weak link.
- 582's don't last. And, unfortunately, these operations are all sustained by tandem thrill rides posing as instruction. And 582's can't do tandems.

- Tug drivers don't need or use muscle. They have joysticks and rudder pedals to operate control surfaces. The hang gliders are the ones who need and use muscle - and lots of it.

- Strong weak links don't cause trouble. They prevent it - exactly for the same reason that four stroke turbocharged engines and strong launch runs do.

- What's your scenario in which the 582 doesn't have the power to put up with the trouble caused by a strong link? Does it develop when the glider's lined up reasonably well behind the tug? Like at Zapata when they blew six Davis Links in a row in light morning conditions due to coincidence issues? If the tug driver is needing to muscle his way out of a problem caused by a strong link it's a lockout and no force on the planet is gonna muscle things back in line. Muscle is only gonna accelerate the problem. A Rooney Link WILL blow and a Tad-O-Link will blow two milliseconds later. There's gonna be a horrendous stall.

060-03626
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063-03805
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If they're high the glider will recover. Otherwise it's dead. And that sequence is with a Rooney Link and it doesn't blow and the tug isn't the least bit fazed. The glider's made the easy reach to his Koch release.

We have absolutely no use for a weak link which holds while the pilot of our big 914T muscles his way out of our problem 'cause that scenario is totally fictional. We want a weak link that won't dump us into a fatal inconvenience stall while we're dealing with thermal turbulence and the tow's sustainable or allows us to continue gaining altitude even when the tow's not gonna be sustainable.

http://ozreport.com/13.238
Adam Parer on his tuck and tumble
Adam Parer - 2009/11/25

Due to the rough conditions weak links were breaking just about every other tow and the two tugs worked hard to eventually get everyone off the ground successfully.
Those aren't people who are so crappy and clueless that they're getting their lives saved every other tow. Weak links in sailplaning function about as often as parachutes do in hang gliding. And we have the capability to keep the tow under control just as well as they do on all but the rarest of occasions.
For a sad example of what can happen to a tug when things go wrong...
Oh good. I'm all ears for sad examples of hang glider AT situations.
In Washington State a few years back a Sailplane operation...
A sailplane operation? So from the entire history of hang glider AT ops you couldn't find a single example?
...had Tug go down.
582 Dragonfly? Just kidding.
During the roll, the Spoilers...
What are "spoilers"? I'd really like to know to make sure I don't make the same mistake.
..."popped" open on the two seater sailplane...
A two seater sailplane. This just keeps getting more and more relevant.
...(with student at the controls).
- So there was an instructor NOT at the controls whom you're not telling us anything about. This must've been a really well checked out student.

- The last time I was a student on a tow flight was 1980/11/14 at Kitty Hawk foot launching on Yarnall winch pulling off the control frame. I didn't have an instructor up with me 'cause by that point I WAS an instructor and a reasonably hot dune pilot.
The Tug pilot sensed a problem as the tow progressed...
That there was a marginally competent student at the controls and an instructor in the back seat with no access to the controls?
...things where simply not happening as they should.
No shit.
He glanced back and saw the spoilers open.
What if he'd glanced back and seen the spoilers open before they'd gotten airborne?
He should have given the glider the rope.
And the instructor in the back seat hadn't caught the spoilers issue and had the student fix things?
He didn't, he powered hard into the tow...
OH. So he reacted to a potential emergency situation by flooring it. I'm confused. Being a glider pilot we have an Infallible Weak Link which instantly chops our thrust to zero. Or a Top Gun tug driver who fixes whatever's going on back there by giving us the rope.
...and got on the radio and screamed at the student to get his spoilers closed.
- Sure. What else could he do? Besides giving the glider the rope I mean?

- Isn't SCREAMING into a radio a bit counterproductive? Don't you get distortion that makes the communication totally unintelligible?

- Yeah, he's SCREAMING at this point 'cause he knows the situation is on the brink of fatality. But he continues the tow. And screaming at a marginally qualified student always produces results vastly superior to what you get calmly talking him through a situation.

- New and improved edition:

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Martin Henry - 2020/09/24 15:26:02 UTC

The tug pilot spotted the issue (and obviously felt it), and radioed back to get the spoilers closed.
There was plenty of energy building and the student realized his error and slammed the spoilers shut.
- Good reactions. Well trained student.

- Wouldn't it have been better if he'd just eased the spoilers shut? No wait... His tug pilot had just SCREAMED to tell him to get his spoilers closed. Guess that wasn't an option.
The glider, now with speed, ballooned rapidly and the student did not react fast enough to compensate...
- How fast does one NEED to react to compensate? Sounds like he was totally fuckin' clueless and had been thrown in way over his head.

- The tug pilot had just achieved outstanding success by SCREAMING at the student to slam the spoilers shut. So how come he didn't scream at the student to compensate fast enough? Seems like a bit of wasted effort on the first communication.
...shooting way too high.
You mean like?:

17-3120
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Lotsa similarities. Zero VG is a bit like spoilers mode and Oliver forgot his two point bridle - like Holly - so he had to stuff the bar to try to keep the nose and glider down - like Holly.
The high tow position, Tug at full power (trying to power his way out of the problem)...
What an idiot.
...the glider was pitching the tug down.
- So why didn't he release? Ditto for the student and his instructor?
- Was there any more screaming reported during this phase?
The rope/weak link failed.
Which was it? The rope or the weak link? It's LEGAL to fly with a rope within weak link specs but it's only a shitrigged operation that would do it.
The Tug still low to the ground at full power, close to stall, nose down, drove straight into the rough ground off the end of the runway and the Tug pilot was killed.
Oh.

- So the tug's still at full power pointing back down at the runway. Whenever I see a tree coming at me when I'm driving I ease off the gas and maybe use some brake.

- So you're saying that when the connection FAILED the situation deteriorated. So what's your point? If the weak link had been stronger and held the tug wouldn't have gone down like a brick? Or that if these assholes hadn't been flying with a Tad-O-Link it would've done what you said the tug pilot (or the glider) SHOULD have done immediately still in time to let the tug come out smelling like a rose?
Flying a Tug with a heavy customer at the end of the towline is a ballet dance with a fat lady, you have to do it right or somebody could get killed.
- We're not the heavy customers. The tandem thrill riders on the draggy tandems are the heavy customers. And they can all get fucked as far as I'm concerned. They have ZERO legitimate purpose under the terms of our original aerotowing exemption.

- If you're doing it RIGHT - like sailplanes always have - you have ZERO situations in which a weak link comes into play - which is the case with sailplanes.

- Hang glider people ARE getting killed. And our only response is to always use an appropriate weak link with a finished length of 1.5 inches or less. And that NEVER WORKS.

- What a load o' total CRAP. This was a massive clusterfuck not far below the level of Jean Lake but with ABSOLUTELY NOTHING to do with hang glider aerotowing. You tell us NOTHING about weak link strength and present this Tad-O-Link guilty case closed.
Now its back to my "Abba's Greatest Hits"...

Cheers
Martin
Yeah Martin, go fuck yourself.

And you'll notice that Davis and all his pet assholes let this lunatic total bullshit slide.

And in the most recently revised edition:

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Martin Henry - 2020/09/24 15:26:02 UTC

The rope broke or somebody hit the release...
We're not even trying to claim that there was all that much tension involved. Is he slightly dumbing down his horror story 'cause now Davis and many of us have become happy with a slightly stronger weak link?
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Tad Eareckson
Posts: 9149
Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

Hey Martin...

http://ozreport.com/forum/viewtopic.php?t=15716
weak links
Martin Henry - 2009/04/26 16:23:56 UTC

The reason I thought I would post is, well your very caught up in your end of the towline you seemed to be in a bit of a battle with the guy (or gal?) on the other end of the line.
My career was over at that point. And by then I had been a Four for over seventeen years and was within striking range of a Five; been instructor rated a couple times; towed about every flavor you can think of dating back to 1980; 184 ATs under my belt one and two point, foot and dolly launched, behind five different flavors of tugs - weight shift and conventional controls.

Who the fuck do you think you are to presume to lecture me about concern for the safety of my tug? We don't get up unless we have our eyes glued to him damn near every second of the climb and react to every little shift in position with a precise adjustment. The tug CAN BE a hot pilot but sure doesn't hafta be and the flying we do needs to be twenty times as precise as his is 'cause it's twenty times more critical to the success of the tow.

Just my AT rating says I understand the issues facing the tug and if that's not valid then what is in this game? If that's not valid then the entire system is crud and the goddam tug drivers are doing shit to rectify it.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Jim Rooney - 2011/08/31 09:25:57 UTC

Your anecdotal opinion is supposed to sway me?
You forget, every tow flight you take requires a tug pilot... we see EVERY tow.
We know who the rockstars are and who the muppets are.
Do you have any idea how few of us there are?
You think we don't talk?
I'll take our opinion over yours any day of the week.
Yeah Jim. Keep running your yap as much and freely as you like. And please don't start thinking a move or two ahead and considering implications.

P.S. Martin... Where's the documentation on this Washington sailplane launch clusterfuck that you keep dragging out to make sure we're all adequately enlightened? I haven't been able to find anything and l'd like to get a version that makes some sense.
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Tad Eareckson
Posts: 9149
Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Matt Pruett - 2020/09/26 00:34:02 UTC

No doubt that the vg is the primary cause here. However just as a side note, I'm confident you were more upright than is optimal, it may be worth some consideration and adjustment over time. I think most people tow a bit higher than is aerodynamically optimal, I know I do, release clearance and so on. But you probably could have been lower, even if you feel like you are low on the cart, you are probably not going to be low when you come out of the cart as you swing forward of the control bar. Not a big deal regardless. Careful with the cart wheels, they were very slanted at the start, it wasn't a problem of course, but I've seen carts go off to one side on the takeoff roll, just good to eliminate any extra variables you can.
No doubt that the vg is the primary cause here.
Yeah Matt...

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No doubt whatsoever. The VG. Case closed. The collective intelligence of the top pilots in the business.
However...
HOWEVER? Why the hell could we have the slightest need of any "howevers"? Let's not complicate things. KISS. As in most cases, the simplest approaches work best.
However just as a side note, I'm confident you were more upright than is optimal, it may be worth some consideration and adjustment over time. I think most people tow a bit higher than is aerodynamically optimal, I know I do, release clearance and so on.
Good thinking, Matt. Release issues are absolutely critical. You wanna avail yourself of the best technology money can buy and if you need to compromise your control authority and glide performance during launch, tow, flight, approach, landing for release clearance and so on then YOU BLOODY WELL DO IT. This is the mark of a REAL pilot.
But you probably could have been lower, even if you feel like you are low on the cart, you are probably not going to be low when you come out of the cart as you swing forward of the control bar.
WAY forward of the bar. And at this point you need to be extremely careful.

http://ozreport.com/forum/viewtopic.php?t=9230
Departing the launch cart
Jim Rooney - 2007/08/24 12:20:06 UTC

Bad habit #1, not flying the glider... just letting the tug drag you around by the nose, combines with the fact that pro towing REQUIRES the pilot to do something (not let that bar move). So instead of holding the bar where it is, bad habit pilot just lets the tug pull him. This pulls him through the control frame with the same effect as the pilot pulling in... a LOT.

I've seen gliders go negative while still on the cart this way.
The results are never pretty.
When you're pulled through the control frame like that it's the same effect as you pulling in... a LOT. I've seen gliders go negative while still on the cart this way. The results are never pretty. So at this point here:

07-2105
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you really need to be doing something to make sure you don't nose in. It's absolutely astounding how many pilots don't understand this.

Once you start getting out of ground effect...

09-2122
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...the aerodynamics start shifting to normal tow mode and you can start stuffing the bar for all you're worth to hold the glider down to proper tow position and be prepared as best as possible to handle a Zack Marzec situation. Yeah, like the rest of us, you have no idea what really happened on that tow and we probably never will know, but the general consensus is the age old adage... "err on the side of caution". Just make goddam sure you never err on the side of caution by even considering use of a two point bridle. That bullshit started going down the toilet about a decade and a half ago. Those theories were annoying at best and downright dangerous most of the time. Good riddance I say.
Careful with the cart wheels, they were very slanted at the start, it wasn't a problem of course, but I've seen carts go off to one side on the takeoff roll...
Yeah, make sure you have EVERYTHING POSSIBLE OPTIMIZED TO THE MAX. This is not a game with which we can afford to fuck around. You don't even wanna think about some of the horrors we can experience trying to start up with misaligned cart wheels. And make sure you haven't accidentally...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links
Jim Rooney - 2007/07/22 22:30:28 UTC

I've heard it a million times before from comp pilots insisting on towing with even doubled up weaklinks (some want no weaklink).
...doubled up your weak link.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Davis Straub - 2011/08/26 14:04:52 UTC

We had six weaklink breaks in a row at Zapata this year. Russell Brown (tug pilot, tug owner, Quest Air owner) said go ahead and double up (four strands of Cortland Greenspot). He knows I used his Zapata weaklink in Big Spring (pilots were asked to tell the tug pilot if they were doing that).
That's just begging for a low level lockout from which you'll have zero chance of escaping.
...,just good to eliminate any extra variables you can.
Yeah, like a two point bridle. It could wrap at the tow ring in a lockout emergency release.

http://www.hanggliding.org/viewtopic.php?t=14230
pro tow set-up
Jim Rooney - 2009/11/02 18:58:13 UTC

Oh it happens.
I have, all the guys I work with have.
(Our average is 1 in 1,000 tows)

Oh yeah... an other fun fact for ya... ya know when it's far more likely to happen? During a lockout. When we're doing lockout training, the odds go from 1 in 1,000 to over 50/50.
Unless you use one of those long thin jobs that Bob Lane and Davis sell.

http://ozreport.com/9.098
The thin 1500 pound aerotow bridle
Davis Straub - 2005/05/03

Bob Lane said that Quest Air sold over forty of their bridles (and Bob sold fifteen or twenty) during the Nationals. The Quest Air bridles use thicker Spectra and are designed not to whip around and accidentally tie themselves to the carabineer. Bob says his bridles will not do this either.
But...

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Jim Rooney - 2011/08/28 19:39:17 UTC

...the "other side"... the not cautions one... is not one of frustration, it's one of very real danger.
Better to be frustrated than in a hospital, or worse.
No exaggeration... this is the fire that the "other side" is made of. Best not to play with it.
...the "other side"... the not cautions one... is one of very real danger. Best not to play with it.

Note the two trees in the bottom right corner of this frame:

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referencing the launch point...

http://c2.staticflickr.com/8/7447/26578855104_69f4705474_o.jpg
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for Jeff Bohl's 2016/05/21 Runway 27 effort.

Look at how high we are and how much safe runway we have around and left in front of us as we're crossing over the intended path. Also the degree of control range we're holding in reserve should we need more speed and/or ability to bring the glider down relative to the tug, limit the climb rate. (Any thoughts on why he's not going down like a brick with the bar stuffed to the extent it is?)
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Tad Eareckson
Posts: 9149
Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

Note: Accidentally clicked "Submit" at the above time stamp - 2020/09/26 16:00:22 UTC - while composing this one. Actual submission time - 2020/09/26 20:30:00 UTC. Sorry 'bout that.
---
http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Jay Z - 2020/09/26 09:07:21 UTC
Steve Pearson - 2020/09/24 22:19:57 UTC

1/2 VG is recommended for aerotowing all Wills Wing gliders configured with VG systems. Towing at less that 50% VG is more difficult because the pitch pressure can be excessively high and that in turn contributes to PIO.
Thank you for that explanation. Apparently those increased pitch pressures also make it harder for the pilot to pull in enough to stay down with the tug.
Yeah Jay. Ya really gotta watch out for those...

http://1.bp.blogspot.com/-2lk6hbjuJ-c/Ujh-ENPLQrI/AAAAAAAA3IQ/vh46chqQX4M/s1600/JRS_0542.JPG
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...PITCH PRESSURES at VG Zero 'cause they can be excessively high and that in turn contributes to PIO. But as long as you follow our recommendation of VG 0.5 you'll be fine. There's no possible scenario under any sane AT conditions in which you'll be totally fucked.

So here's the timeline...

- 1981. Donnell Hewett and the biggest load of faith based snake oil to be swallowed by the gallon in aviation history. Four decades and... (http://birrendesign.com/rhgpa_criteria.html - 2020/09/26 - They are as viable today as they were in the early 80's when he wrote them.) ...still going strong.

- 1983. Cosmos trike tug, foot launch, everybody's flying one point - and getting away with it 'cause the activity level is way too low for everything to line up right à la Zack Marzec. Continues through the mid to end of the Eighties.

- Early Nineties. Dragonfly, dolly launch, 1.5 point bridle, panic snap release, non easily reachable cable loop on the control bar. I don't think we were using Infallible Weak Links.

- Mid to Late Nineties. Two point, welded Wichard spinnaker shackle release, easily reachable bicycle brake lever securely velcroed to the starboard control tube to give you more leverage to pry open your spinnaker shackle under load but not a long enough pull range to open the spinnaker shackle under no load. Infallible 130 pound Greenspot Standard Aerotow Weak Link to get you safely off tow after your Fallible spinnaker shackle fails and before you can get into too much trouble.

- Late Nineties to Early Aughts.

-- The really Kool Kids start developing the skills they need to safely fly pro toad using only their indeed very very reliable bent pin backup releases - with a Standard Aerotow Weak Link on the other end of the bridle for the exceptionally rare occasion on which the mechanical thing inevitably fails. Plus a hook knife just to be on the really safe side.

-- 1998/01. Dennis Pagen and his fake coauthor Bill Bryden (to make it harder to pin this motherfucker down on any of the total crap he wrote) publish their excellent book - Towing Aloft. It's a total Flight Park Mafia infomercial to help sell their product and illustrate how it's totally impossible to get so much as skinned knee under any AT circumstances as long as you're not some total moron who uses a Tad-O-Link to trade off safety for the sake of convenience.

- Mid Aughts to Early Teens.

-- Quest spinnaker shackle gets rotated ninety degrees towards Twelve so the Infallible Weak Link will pull perpendicularly on the gate to pull it open more reliably with no load on it.

-- 2004/08/01-07 - US Nationals at Big Spring. u$hPa / Flight Park Mafia shill Dennis Pagen comes within two and a half inches of getting his stupid pro toad ass fatally splattered when he encounters actual thermal conditions low in the kill zone. This is a MAJOR problem for the Industry. They're on the record telling people it's perfectly safe to go one point (No, let's start calling it TWO point 'cause that sounds a lot safer. And let's call two point THREE point 'cause that sounds dorky, complex, Rube Goldberg, totally uncool.) and they can NEVER afford to take that back.

-- 2005/01. In the magazine there's an "HG Accident Reports: U.S." by u$hPa Damage Control Officer Joe Gregor starting on Page 50. And starting on Page 68 there's an "HG Accident Reports: Europe" by world's greatest expert on anything and everything hang gliding Dennis Pagen. And this is the first and undoubtedly last time since the days of R.V. Wills that u$hPa ever gave the least flying fuck about anything that ever happened outside of US turf.

Conspicuously unidentified German Pagen victim changes his nose and tail wires to move the control bar back to a safer position. Goes up pro toad and hit one of those thermals on launch that appear nowhere in Dennis's excellent book and locks out and fatally splatters still on tow 'cause he previously hadn't thanked his tug pilot enough for intentionally releasing him, even when he felt he could have ridden it out. (I wonder why he didn't release himself and why his weak link didn't
very clearly provide protection from excessive angles of attack, high bank turns and the like for that form of towing. Must've been using home made gear and a Tad-O-Link.)

Him being killed this is an accident. This paves the way for Dennis to report on his experience - which wasn't an accident 'cause he didn't get so much as a grass stain. We need to think twice about putting Twos up pro toad. It's not fundamentally dangerous - you just need to be adequately experienced, skilled, prepared to release quickly in situations like this. Probably a good idea not to use a Tad-O-Link but we can only assume that 'cause Dennis strangely makes no mention of either back or front end weak links - even though he's seriously endangering the very experienced tug pilot, Neal Harris, who seriously risked his life keeping him on. (Big thanks to you Infallible Weak Links too, guys. I'm sure the absence of gratitude from Dennis was just an unfortunate oversight.)

OK, so now our ass is covered. If you get killed in a situation like this it's only 'cause you were a shit pilot going in over your head without taking the short clinic Steve Wendt runs every third Sunday at Blue Sky.

-- 2005/02. Rob Kells publishes in the magazine (wow, look at the timing) the guidelines for connecting and trimming Wills Wing gliders for AT. The Sport 2, U2 and Talon may be "Pro towed" without a top release; however this method is not as easy as using a two-point release as described above. Towing without a top release will cause the basetube to be positioned much farther back during tow, the glider will have increased pitch pressure, and lockouts are more difficult to correct. Not really dangerous though, it just makes the lockout MORE DIFFICULT to CORRECT.

-- 2005/05/29. Holly Korzilius recklessly hops on a cart at the Wills Wing affiliate Blue Sky Hang Gliding runway minus her three point bridle and Standard Aerotow Weak Link in violent afternoon thermal conditions and two thirds kills herself and nearly kills the tug because she hadn't first taken the short pro toad clinic Steve Wendt runs every third Sunday at Blue Sky. A MASSIVE Industry cover-up/disinformation campaign is launched to limit damage.

-- 2005/09/03. Arlan Birkett and Jeremiah Thompson get fatally inconvenienced when they get too low behind the tug and their tandem glider became unattached from the tug. Don't worry about your Infallible Weak Links though. Everything's still fine with them.

-- 2007/02/01. Davis has defined pro toad bridles as the only appropriate ones for participation in World, US, Australian competitions. Two point bridles have subsequently been outlawed.

-- 2007/05/16. T** at K*** S****** fires the opening salvo in the war against a quarter century of all this Infallible Weak Link bullshit.

-- 2008/07/20. The Tad-O-Link that Tad forced Paul Tjaden to fly with at Zapata comes within a hair's breadth of killing both Paul and Russell Brown when it doesn't break when it's supposed to. The Dragonfly weak link is reduced from 0.99 percent Tad-O-Link to 0.75 percent Tad-O-Link without notification.

-- 2011/06/16. Davis is kind enough to inform Zack C that his understanding that the pro toad configuration pulls the pilot forward significantly, limiting the amount he can pull in further (see Pearson Santa Cruz launch photo above), is an incorrect one.

-- 2011/08/11. At Zapata six consecutive Standard Aerotow Weak Links coincidently increase the safety of the towing operation at under fifteen feet in light morning conditions. The last inconvenience sends Pete Lehmann to the emergency room. Russell Brown (tug pilot, tug owner, Quest Air owner) decides Tad-O-Links aren't such a bad idea after all. Just tell the tug pilot if you're using on so he'll be extra careful launching you and getting you up through the kill zone. The Dragonfly weak link is increased back up to 0.99 percent Tad-O-Link without notification.

-- 2013/02/02. Tandem aerotow instructor and intimate friend of Jim Keen-Intellect Rooney goes up pro toad with a Standard Aerotow Weak Link pitch and lockout protector at Quest, does a somewhat more spectacular rerun of Pagen at the 2004/08 Nationals, doesn't react quickly enough, experiences a fatal inconvenience tumble. Mark Frutiger, his driver, is traumatized enough to blurt out an honest account of the incident before anyone can stop him but after getting settled down for several days doesn't want to speculate on what actually happened. Ten hours after impact many of us have suddenly become happy with a slightly stronger weak link. Rooney is shattered. Considering becoming an asshole. With all the nice people dying, it just seemed safer.

-- 2013/05/09. Ben Dunn behind Joel Froehlich pro toad at Lulling gets hit by a dust devil at low altitude, gets stood on his ear, dumped by his driver, dropped into a near fatal vertical stall. Makes the cover of the 2014/01 magazine cover - with no comment anywhere about the near fatal incident.

- Mid Teens to Present.

-- 2015/03/27. The most massive clusterfuck in world hang gliding history takes out a u$hPa Master fake instructor and an eleven year old kid fake student at Jean Lake in front of the latter's family on a circuit tow effort using a Wills Wing tandem glider. Team Kite Strings puts just about all the jigsaw puzzle pieces together and publishes. u$hPa loses its insurance coverage from then on to the end of time. Wills Wing never heard anything about it.

2016/05/21. Senior United Airlines pilot Jeff Bohl dies on an appropriate Wills Wing T2C 144 with an appropriate bridle and appropriate 200 pound Tad-O-Link behind an appropriate 582 tug on an appropriate short runway in appropriate nothing conditions 'cause he makes an inappropriate one second snatch for an unsecured camera.

2020/09/19. Oliver Moffatt AT launches pro toad behind a trike at Balado in nothing conditions at half VG, has the VG pop off just off the cart, climbs out with the bar totally stuffed to BHPA appropriate weak link relative altitude SOLELY BECAUSE his VG wasn't adequately secured. Steve Pearson weighs in and tells him that he needs to be using VG 0.5 'cause at lower the bar pressure will be too great and he'll be prone to oscillation. Pitch trim and available pull-in range have absolutely nothing to do with anything.

Once some lunatic configuration, piece of alleged equipment, procedure, theory gets into circulation via a mainstreamer and fails to maim or kill people more than once every other weekend it will NEVER be eradicated or condemned. u$hPa certified and highly esteemed Instructor of the Year and Wills Wing dealer Steve Wendt runs pro toad clinics every third Sunday then there's never any real advantage to two point 'cept maybe for single surface Two fags without much aptitude for this game. They want ALL double surface gliders flying one point 'cause the more of them there are out there the more TYPICAL the configuration is and the less liable anybody is for anything.

It's absolutely astonishing watching Pearson come off the cart with the bar fully stuffed but the typical hang glider pilot sees nothing that looks the slightest bit off.

http://airtribune.com/2019-big-spring-nationals/info/details__info
2019 Big Spring Nationals (pre-Pan-Americans)
http://airtribune.fra1.digitaloceanspaces.com/media/contest/files/2019/07/GTxd6mT4AIn8.pdf
Local Rules
15 - Launch

Weaklinks of 140 and 200 pounds will be available and provided by the organizers. Weaklinks provided by the organizers must be used by the competitors.
Davis was always too brain damaged to tell/remember the difference between 140 and 130. He MEANS 130 'cause that's what he MANDATED for a couple decades.

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Jim Rooney - 2013/03/04 19:31:36 UTC

We all play by the same rules, or we don't play.
No we don't. 200 pounds / 400 towline is a figure we could all live with well enough. But Davis can't take 130 off the table 'cause that would be an admission that 130 was inappropriate and potentially dangerous. The LAST thing a slimeball corporate lawyer wants to do after a Zack Marzec is take 130 out of circulation. Nah, it's still typical. We've just recognized over the course of hundreds of thousands of AT launches that a lot of our more intuitive and advanced pilots have developed the skills and judgment to be flying the slightly stronger stuff. And it cuts down on the inconvenience issues a fair bit in choppy marginal conditions. Trail and error ya know.
User avatar
Tad Eareckson
Posts: 9149
Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

Delayed. Actually posted 2020/09/27 17:20:00 UTC
---
It's a major BITCH to design and build a real quality, bulletproof, clean, built-in, two point AT release system.

http://www.flickr.com/photos/aerotowrelease/8318603266/
Image

I'm the only individual in the hang gliding history of the planet to do it and Antoine is the only individual to have duplicated it. Back before u$hPa / Flight Park Mafia machinery really got rolling there was a fair handful of Capitol Club assholes who were blown away by it and publicly posted to that effect. Rob Kells praised my engineering PRIVATELY. But it made the cheap shoddy crap Ridgely was passing off and selling as towing equipment look like the cheap shoddy crap it actually was, they weren't ever gonna adopt it, so they had fun pissing all over it and me. Ditto for dregs like Bo Hagewood, Steve Wendt, Matt Taber and later Karl Allmendinger, Trisa, Bart...

These are all Wills Wing dealers and most US glider jocks are Wills Wing customers so this is just slightly downstream Wills Wing shit and piss that's getting dumped on me.

This:

http://1.bp.blogspot.com/-2lk6hbjuJ-c/Ujh-ENPLQrI/AAAAAAAA3IQ/vh46chqQX4M/s1600/JRS_0542.JPG
Image

That's a super cool looking comp glider with a super cool looking comp pilot in a super cool looking comp harness doing a super cool looking comp AT launch. It just screams performance, efficiency, speed, power. If Steve were just back in a sane trim position it would look a lot less super cool. Just the thought of velcroing Quest's abortion of a two point release assembly to one of those thousand dollar carbon control tubes makes ya wanna puke. Stuck on some slightly baggy 2.5 level glider with round downtubes it's a lot less noticeable.

If you built my release into the T2C's port downtube - exactly the way they built their VG control stuff into the starboard downtube - you'd never see it and there'd be virtually zero drag penalty. And Steve would be in a safe sane trim position. But you'd still wanna use the pro toad shot for advertising - despite the fact that he's a total dope on a rope.

History shows that you CAN get away with untold tens of thousands of pro toad launches - if you're not doing too much other stupid shit at the same time.

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Mark Frutiger - 2013/02/09 02:31:37 UTC

The turbulance level was strong, among the strongest thermal activity I've felt leaving the field. I've encountered stronger mechanical mixing, but the vertical velocity this time was very strong.
Not a big fucking deal. But a real big chunk of his pulls are tandem thrill rides and those are ALL two point. So... Not a problem. And on the back end you have:

http://farm4.staticflickr.com/3746/13864051003_a820bcf2b8_o.png
Image
06-03114
http://farm4.staticflickr.com/3728/9655895292_f4f808fb0e_o.png
Image

Nah, we don't need to abort this tow. What's the worst that could happen?
Mark Frutiger - 2013/02/08 19:12:21 UTC

Zack hit the lift a few seconds after I did. He was high and to the right of the tug and was out of my mirror when the weak ling broke. The load on the tug was not excessive as with a lockout, but I was not surprised when the weak link broke. I was still in the thermal...
Nah, nothing surprising at all. The load on the tug was not excessive as with a lockout and...
Jerry Forburger - 1990/10

High line tensions reduce the pilot's ability to control the glider and we all know that the killer "lockout" is caused by high towline tension.
...we all know that the killer "lockout" is caused by high towline tension so this obviously wasn't a lockout situation and NOBODY's surprised when the weak link breaks. We're surprised when...

http://ozreport.com/13.238
Adam Parer on his tuck and tumble
Adam Parer - 2009/11/25

Due to the rough conditions weak links were breaking just about every other tow and the two tugs worked hard to eventually get everyone off the ground successfully.
http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Davis Straub - 2011/08/26 14:04:52 UTC

We had six weaklink breaks in a row at Zapata this year. Russell Brown (tug pilot, tug owner, Quest Air owner) said go ahead and double up (four strands of Cortland Greenspot). He knows I used his Zapata weaklink in Big Spring (pilots were asked to tell the tug pilot if they were doing that).
...the weak link DOESN'T break. And if we double it up we need to tell the tug pilot so he won't be surprised when it doesn't break.

We don't mountain launch when we see a thermal rolling up the slope. We wait until we're either in it or, if there's a fair bit of wind / ridge lift, wait until it passes.

The tug virtually always gets and gives advance notice of what's gonna be happening to the glider in several seconds and you have two pilots who can abort the launch. Continuing the tow is a lot like taking the glider out on the ramp in Assisted Windy Cliff Launch conditions with no Assistance. And look what happened to Craig Pirazzi just trying to ground handle his glider behind and approaching launch while hooked in minus Assistance. Pretty much identical results for totally analogous reasons.

But I think it's real safe to say that not once in the entire world history of hang glider aerotowing has a tow still down in the kill zone been aborted by either end after the tug got hit and while the glider was still OK. For properly trimmed two point behind a slow capable Dragonfly that should be OK. If the tug can handle it the glider should be able to handle it nearly as well and the tow should be sustainable.

The rule of thumb is that you need a minimum of three things going wrong simultaneously to get killed. That doesn't mean you WILL be killed - Kelly Harrison had so much shit wrong that it's tedious to list - the final straw being that although he never flew without a parachute he had never given a thought about a situation in which he'd need to use it.

We look at Steve:
- pro toad such that the bar needs to stay stuffed just to be able to stay down level with the tug on your average tow
- release:
-- easily reachable
-- bent pin so stays welded shut under load
- Infallible Weak Link
- long thin pro toad bridle that won't wrap at the tow ring
- no wheels - even though he says he can't control his glider with my hands on the control tubes at shoulder or ear height
- tug driver who can fix whatever's going on back there by giving him the rope

Expansion on a couple of those...

- If we use the full rez URL for the photo and zoom in we can get a fair look at his bridle/release assembly. We can confirm a piece o' crap Bailey "release" on his right shoulder and it's a fair bet that he's using a Davis Link. With a gun to my head I'd say we have 130 pound Greenspot at the starboard end of the bridle.

- Also it's gotta be a Davis Link 'cause he told us to always use a 2005/02 appropriate weak link and never updated or rescinded that specification.

All of those issues - or reasonable facsimiles - have at one time or another been necessary factors in most of our relevant fatals.

Steve has, like everybody else, ZERO chance of releasing in a low level lockout emergency - à la Steve Elliot and Jeff Bohl. But we still SHOULD BE able to launch him safely, still minus wheels or skids (if he crashes on a landing not relevant to the tow it's not relevant), after we swap in a Tad-O-Link, in good soaring conditions ten thousand times consecutively IF we don't do anything else STUPID.
- We take a 914 Dragonfly tug, shoot the pilot, swap in a halfway competent sailplane tug pilot.
- Good open runway like Quest, Lockout, Currituck, Ridgely, Luling, Zapata, Santa Cruz...
- Healthy sprinkling of windsocks, flags streamers loosely surrounding the glider launch area and down the runway
- Competent conscientious launch assistant to double check the glider and verify flags before signaling.

We check out the glider thoroughly to make sure there are no unsecured cameras or unstowed harness lines to snag the cart.

We make sure nothing's going on with the flags. I was coming down at Ridgely one time and the socks were all over the place. Decided to final in the direction the tug was pointed. Trashed a downtube 'cause I tried to foot land. A dust devil had been coming through and the flags had made it OBVIOUS that it wouldn't have been a good time launch.

We can launch with a 10 mph crosswind but we don't go short runway to launch into the wind.

We abort the tow if we hit a monster thermal before clearing the kill zone.

Hell, I think if we had just SLOWED THE FUCK DOWN when we got hit the Zack Marzec would've at least been survivable and quite likely sustainable. Notice we don't have one single other tumble from an AT incident anywhere at any altitude? At altitude where we're a hundred times more likely to get hit by a monster thermal? Notice that Mark never said anything about slowing down, whether he could have or not?

http://groups.yahoo.com/group/flyhg/message/17223
Pilot's Hotline winter flying
Mark Frutiger - 2013/02/03 13:41

Yesterday was a light and variable day with expected good lift. Zach was the second tow of the afternoon. We launched to the south into a nice straight in wind. A few seconds into the tow I hit strong lift.

Zach hit it and went high and to the right.
A few seconds into the tow he's LOW. He’s wired into takeoff mode and the thought of slowing down never occurs to him. He has the option of chopping the engine to idle and rolling in. As it was Zack hit the thermal at high speed with the bar stuffed since coming off the cart. And they were launching to the south into a nice straight-in wind so there was a gradient. Zack had TONS of airspeed as he was slamming into the thermal.

And...

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Paul Tjaden - 2013/02/07 23:47:58 UTC

The tow aircraft was a Moyes Dragonfly with a 914 Rotax engine and was piloted by a highly experienced tow pilot.
...
Beyond these facts anything else would be pure speculation.
http://ozreport.com/forum/viewtopic.php?t=9230
Departing the launch cart
Mark G. Forbes - 2007/09/01 01:39:39 UTC

914 launches

Jim, just wondering here...

Is it reasonable to not go to full throttle right off with the 914-powered tug, to give a 582-familiar pilot a bit of a transition? I realize the 914 provides a lot more thrust, but can you ramp it up a little slower and give the dope on the rope time to adapt?

Seems like you could go a little slower to start, then pour the coal on once he's rolling well and starting to lift off. Or are there other factors?

MGF
(582-powered Mustang 19 trike tug)
Jim Rooney - 2007/09/01 02:39:53 UTC

Yes, it's technically possible in a theoretical sort of way.
Yes, there are other factor, which is why it isn't done...

First off I guess is that a simple conversation fixes the problem, or the problem is unfixable.
Let me explain.
See one side is lack of information, the idea that 914s require a different launch technique.
The other is a pilots willingness to adjust.
The first is easily solved with a simple conversation but only if the second is possible.

See, there's no 'learning curve'. You either wait stubbornly till you're lifting the cart, cuz "that's the 'right' way", or you don't. The timing is easy. You actually have to work hard to leave the cart at the wrong time (early or late).

Next up... I already do.
I don't tow solos under full power... you could't keep up with me if I did. I wouldn't be going faster horizontally, but my accelleration and climb rate would be so extreme that most pilots couldn't keep up the timing needed to make it work. (I think Bo's the only one I've successfully towed at full boost)

Which brings us to the reason to have a 914 in the first place... you need one.
Something made you get a 914 instead of a 582. 914s are horribly expensive to own and maintain. If you own one, you need it... it's a safety thing. Short runways, tall trees, whatever. You've got a 914 to increase your safety margin. So when it comes down to my safety or having a conversation, we're going to have a conversation. Wether you chose to adjust is then up to you.

In the end, it really does boil down to a willingness to adjust.
It's not a skill thing. The timing is exceptionally simple. 1st time solos do it all the time.
It's as simple as saying "I'm going to let the glider fly out of the cart when it starts tugging on the handles/rope instead of insisting that the cart becomes airborn before I let go."
Gee Paul... In all that extensive reporting on this game changer incident one would've thunk there'd have been some mention of POWER. But I guess beyond these facts anything else would be pure speculation.

OK, I'm gonna speculate that Zack wasn't "most pilots" (treasured friend of Jim Rooney's, in fact) and that he was able to keep up the timing needed to make it work. Just check out 06-03114 above. That's obviously someone who's easily able to keep up the timing needed to make it work. Trained professional in fact. Definitely not the kind of flying one of us muppets would wanna try at home.

Feel free to correct me on this one, though. This is just pure speculation on my part. And I fly three point and just let the tug drag me around by my nose. Pro towing REQUIRES the pilot to do something and that's a huge turn-off for me.

GOTCHYA, motherfuckers. Over seven and a half years later the picture suddenly becomes a lot more clear.

So now we understand why this one was so severe it resulted in a tumble. Could we have slowed the tug down with stuff breaking off like that? Maybe not, but:
- if we're not gonna do that we needed to abort a second ago
- we've already made a shit decision pulling him pro toad
- we need to always be thinking in "what if" mode and prepared to take the best / least shitty option

So now name some AT launch crashes that wouldn't have been prevented if these procedures, strategies, responses had been adhered to, employed, implemented.
User avatar
Tad Eareckson
Posts: 9149
Joined: 2010/11/25 03:48:55 UTC

Re: bridles

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Mark Frutiger - 2013/02/08 19:12:21 UTC

Zack hit the lift a few seconds after I did. He was high and to the right of the tug and was out of my mirror when the weak ling broke. The load on the tug was not excessive as with a lockout, but I was not surprised when the weak link broke. I was still in the thermal when I caught sight of Zack again. I did not see the entry to the tumble, but I did see two revolutions of a forward tumble before kicking the tug around to land. The thermal was still active in the area that I had just launched from so I did a go round and landed on a runway 90 degrees cross to the direction we were towing in.

I would be more than happy to answer any questions pertaining to what I saw and experienced, but I prefer not to engage in speculation at this point.

Thanks,
Mark Frutiger
And thanks zillions to you, Mark - for providing your observations and every known detail of any conceivable degree of relevance concerning this terrible, unprecedented...
Dennis Pagen - 2005/01

FATAL TOWING ACCIDENT

SUMMER 2004 ACCIDENT REPORTS

The first accident occurred in Germany at an aerotowing competition. The pilot launched with his Litespeed and climbed to about 40 feet when he encountered a thermal that lifted him well above the tug. After a few moments, the glider was seen to move to the side and rapidly turn nose down to fly into the ground, still on tow, in a classic lockout maneuver. The impact was fatal.

Analysis

This pilot was a good up-and-coming competition pilot. He had been in my cross-country course three years ago, and this was his second year of competition. What happened to him is not too unusual or mysterious. He encountered so much lift that although he was pulling in the base bar as far as he could, he did not have enough pitch-down control to get the nose down and return to proper position behind the tug. This situation is known as an over-the-top lockout.

I am personally familiar with such a problem, because it happened to me at a meet in Texas. Soon after lift-off the trike tug and I were hit by the mother of all thermals. Since I was much lighter, I rocketed up well above the tug, while the very experienced tug pilot, Neal Harris, said he was also lifted more than he had ever been in his heavy trike. I pulled in all the way, but could see that I wasn't going to come down unless something changed. I hung on and resisted the tendency to roll to the side with as strong a roll input as I could, given that the bar was at my knees. I didn't want to release, because I was so close to the ground and I knew that the glider would be in a compromised attitude.
...mysterious tragedy. But thanks to a recent revelation from Steve Pearson, undoubtedly the world's foremost glider designer and authority on towing, we may now have some new relevant information to help us finally get something of a handle on this one.

http://ozreport.com/forum/viewtopic.php?t=63574
VG Undone
Steve Pearson - 2020/09/24 22:19:57 UTC

1/2 VG is recommended for aerotowing all Wills Wing gliders configured with VG systems. Towing at less that 50% VG is more difficult because the pitch pressure can be excessively high and that in turn contributes to PIO.
Zack may not have been using any or adequate VG.

http://c1.staticflickr.com/5/4174/34261733815_bfb41c49d8_o.jpg
Image

If he'd had under fifty percent the tow would've been more difficult because the pitch pressure could've been excessively high and that in turn could've contributed to PIO.

Copied and pasted right out of:
Rob Kells - 2005/02

Master's Tips:
Aerotow Release Attachment Points for Wills Wing Gliders


VG Setting

All Wills Wing gliders equipped with VG are easiest to tow with the VG set to 1/2. This reduces the glider's pitch bar pressure, while at the same time damping the roll response to reduce the chance of oscillations on tow. Pilots at the light end of the recommended weight range may want to set the VG at 1/3 on.
...with ABSOLUTELY NOTHING about:

Aerotow Release Attachment Points

And in the original reporting from the people who were there we had absolutely nothing about VG setting.

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Paul Tjaden - 2013/02/07 23:47:58 UTC

Beyond these facts anything else would be pure speculation.
Just crap these douchebags pulled outta their asses about nonexistent Florida dust devils 'cause big fat thermals are the reason we fly and dust devils are freak occurrences we try to avoid like the plague.

By 2013/09/01 u$hPa has decided that the:
- actual incident date was 2013/02/08
- glider was hit with no warning by "an invisible bullet thermal (that snuck in between the tug and glider)
- "fairly old design" Moyes Xtralite was the pilot's "own high performance glider with VG on"
And he "was not wearing a full face helmet" which would have virtually certainly have prevented the fatal injuries he suffered. (DAMN! I just realized he probably wasn't wearing any helmet AT ALL!)

Doesn't say HOW MUCH VG - so pretty safe bet it was probably too much or too little.
VG Setting

All Wills Wing gliders equipped with VG are easiest to tow with the VG set to 1/2. This reduces the glider's pitch bar pressure, while at the same time damping the roll response to reduce the chance of oscillations on tow.
My Wills Wing glider is an HPAT 158. The VG is a lever so your choices are zero or one hundred percent. I did both but later in my career went with ON 'cause at towing speed - which is relatively high - roll control response is a nonissue and you're flying more efficiently. But it's not a BFD one way or another. And I somehow managed to survive without ever once having flown with a fin on anything.

The report says the bullet thermal pitched the nose up (as opposed to pitching the port wing up), causing the weak link to break but can't be bothered to tell us what the focal point of Zack's safe towing system actually was..

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Rooney - 2013/03/07 18:24:58 UTC

You're the one advocating change here, not me.
I'm fine.

These are only questions if you're advocating change. Which I'm not. You are.

You're the one speculating on Zack's death... not me.
Hell, you've even already come to your conclusions... you've made up your mind and you "know" what happened and what to do about.
It's disgusting and you need to stop.
You weren't there. You don't know.
All you have is the tug pilot report, who himself says he doesn't know... and HE WAS THERE... and he doesn't know.
And not a single one of the motherfuckers who WERE THERE has ever voiced the slightest issue of this u$hPa abortion of a "report". Also not the mega douchebag just quoted. No way in hell that coward's ever gonna take on anybody he thinks has any power to damage him.

This weak link was 130 pound Greenspot...

27-40324
http://farm9.staticflickr.com/8394/8696380718_787dbc0005_o.png
Image

...big surprise and as Paul confirms for us. We know that a pristine loop can blow for an average weight topless pro toad anywhere from glassy dead sled coincidence five feet off the cart up to 260 pound towline or a bit up. (Yeah, Davis...

http://ozreport.com/12.081
Weaklinks - the HGFA rules
Davis Straub - 2008/04/22 14:47:00 UTC

For many years a number of us (US pilots) have felt that #8 bricklayers nylon line was not an appropriate material to use for weaklinks as it is not as consistent in its breaking strength (as far as we are concerned) as the Greenspot line used in the US.
...Right.) And we know that Zack's held until it after the glider was blasted up and standing on its tail so it was probably holding to around textbook capacity. The primary concern regarding the mandatory limit for the Standard Aerotow Weak Link was that anything five pounds or up heavier (on a solo) would immediately start killing tugs at a rate of at least three per weekend. And yet:

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Mark Frutiger - 2013/02/08 19:12:21 UTC

Zack hit the lift a few seconds after I did. He was high and to the right of the tug and was out of my mirror when the weak ling broke. The load on the tug was not excessive as with a lockout, but I was not surprised when the weak link broke.
And now:

http://airtribune.com/2019-big-spring-nationals/info/details__info
2019 Big Spring Nationals (pre-Pan-Americans)
http://airtribune.fra1.digitaloceanspaces.com/media/contest/files/2019/07/GTxd6mT4AIn8.pdf
Local Rules
15 - Launch

Weaklinks of 140 and 200 pounds will be available and provided by the organizers. Weaklinks provided by the organizers must be used by the competitors.
So a four hundred pound straight up vertical pull on the Dragonfly's tail is also no issue in nosing it in on launch.

No wait...

http://ozreport.com/forum/viewtopic.php?t=32824
Weaklink testing
Davis Straub, Mark Knight, Jim Rooney - 2013/07/04 13:47:57 UTC

Breaking Lbs - Material
330 - Actual Tug Weaklink (Doubled Black) Black Dacron fishing line 160 lb.
So let's be conservative and assume a sixty degree apex angle and say 574 (or nicely over a quarter ton).

And now nobody can ever again say anything about AT weak links or two point bridles and trim points without IMMEDIATELY getting his head blown off so now the only way to protect the tug is to use the proper VG setting.

Also...

http://ozreport.com/5.126
Flytec Dragonfly
USAFlytec - 2001/07/14

Steve Kroop - Russell Brown - Bob Lane - Jim Prahl - Campbell Bowen

The tail section of the Dragonfly is designed so that it can accept in-line as well as lateral loads. Furthermore the mast extension, which is part of the tow system, is designed to break away in the event of excessive in-line or lateral loads. The force required to cause a breakaway is roughly equivalent to the force required to break the double weaklink used on the tail bridle. More simply put, the mast would break away long before any structural damage to the aircraft would occur.
Yeah. Bobby Fucking-Genius Bailey carefully designed the tow mast to blow at a double loop of 130 - to be extra safe for those rare occasions when their precision fishing line ups its breaking strength 33 percent. But now we're upping our weak link 23 percent but still using the same precision breakaway tow mast. Right.

Actual timeline...

- 1989. Bobby uses what-the-fuck-ever for his tow mast.

- The Quest branch of the Flight Park Mafia...

http://www.questairforce.com/aero.html
Aerotow FAQ
Quest Air Hang Gliding

Weak Link

The strength of the weak link is crucial to a safe tow. It should be weak enough so that it will break before the pressure of the towline reaches a level that compromises the handling of the glider but strong enough so that it doesn't break every time you fly into a bit of rough air. A good rule of thumb for the optimum strength is one G, or in other words, equal to the total wing load of the glider. Most flight parks use 130 lb. braided Dacron line, so that one loop (which is the equivalent to two strands) is about 260 lb. strong - about the average wing load of a single pilot on a typical glider. For tandems, either two loops (four strands) of the same line or one loop of a stronger line is usually used to compensate for nearly twice the wing loading. When attaching the weak link to the bridle, position the knot so that it's hidden from the main tension in the link and excluded altogether from the equation.

IMPORTANT - It should never be assumed that the weak link will break in a lockout.
ALWAYS RELEASE THE TOWLINE before there is a problem.
...runs the advanced mathematics to identify the precise strength needed to terminate the tow of a typical glider with the average wing load of a single pilot before the pressure of the towline reaches a level that compromises the handling of the glider but not so much before that it breaks every time you fly into a bit of rough air. (Just eighty to ninety percent of the time you fly into a bit of rough air. Or just a hundred percent of the time you try to launch in glassy smooth light morning conditions. (They didn't tell us what it's supposed to do when you fly into a bit of smooth air.))

- The above weak link is doubled so that it works equally well for tandems.

- 2001/07/14. Dragonfly tow masts are getting bent in the course of normal use. Chintzy engineering, design, construction? OF COURSE NOT!!! We designed it that way for redundancy in the most critical of our award winning safety system. (You morons.)

- 2004/09. FAA pulls hang gliders in to operate under sailplane weak link regs established at the beginning of time. Best kept secret in world aviation history - including the development of the Mitsubishi A6M Zero and attack on Pearl Harbor.

- Flight Park Mafia quietly sneaks the Dragonfly four strand weak link down to three strand to protect Bobby Fucking-Genius Bailey's chintzy tow mast from routine tow loads - while leaving the tandem ride at four.

- 2008/07/20. Paul Tjaden's four strand equivalent pro toad Tad-O-Link rips Russell Brown's towline off while Paul's flying one-handed pro toad through a thermal blast at Zapata.

- 2008/11/13. In order to show everybody what an unparalleled AT expert he is, Jim Keen-Intellect Rooney spills that the Flight Park Mafia has gone to three strand up front.

- 2009. T** at K*** S****** goes ballistic and into whistle blower mode. Scares u$hPa / Flight Park Mafia operatives shitless. End his career and do their best to try to neutralize him. Doesn't work. Nothing they do ever works at a sustainable level.

- Flight Park Mafia probably starts losing towlines to tandems and quietly dials back up to four strand 130.

- 2010/11/23. Kite Strings.

- 2011/08/11. Six consecutive light morning conditions coincidental Davis Link inconveniences at Zapata, last one sends Pete Lehmann to the emergency room. Russell determines that they'll still be good cutting the safety margin of the comp pilots in half - 'specially if the comp pilots tell the tug pilots they are doing this.

- Tugs get tired of losing ropes and have realized that they're gonna keep bending Bobby's chintzy tow mast no matter what. Quietly up the front end to a double loop of 160. Tug pilot fatality rate fails to ramp up significantly.

- 2012/06. u$hPa / Flight Park Mafia makes desperation last gasp effort to prop up their one-size-fits-all 130 pound Greenspot Standard Aerotow Weak Link scam. Publishes mind-bogglingly moronic fourteen page article explaining how beautifully the Standard Aerotow Weak Link works to comply with the regulation they only now inform us of that if we wrap and tie it onto the bridle such that it breaks more consistently in accordance with our expectations.

- 2013/02/02. Zack Marzec gets pro toad inconvenience splattered by his pro toad bridle / Standard Aerotow Weak Link combo at Quest. Jim Keen-Intellect Rooney isn't smart enough to know when he really needs to shut the fuck up. The Flight Park Mafia has been quietly retooling to Tad-O-Links and Rooney's become a massive liability to them. Davis allows Team Kite Strings to demolish him. This paves the way for Davis and many of us to become happy with a slightly stronger weak link.

- 2013/07/04. u$hPa / Flight Park Mafia has Mark Knight and Jim Keen-Intellect Rooney plagiarize what T** at K*** S****** has been saying and doing for the previous sixteen years, pretend to do legitimate load testing, publish numbers, start getting weak links which may not break when they're supposed to into open circulation. Publish what the Dragonfly tug is now actually using so they can continue using what they've always used on the tandem thrill rides and document that they've been operating in compliance if/when something relevant bad happens.

- 2016/05/21. Something relevant bad happens. Airline pilot Jeff Bohl locks out pro toad at Quest and his 400 pound towline solo Tad-O-Link breaks both before he can get into too much trouble and before both April Mackin's 582 Dragonfly's 574 pound towline and 400 pound towline breakaway tow mast break. He only gets into too much trouble 1.5 seconds after April's responsibility as Pilot In Command is terminated.

- 2018/04. Wallaby pioneers the technique of keeping pushed out on the cart so you don't stay on it too long. (Wow. I remember the days when they told us to stay pulled in on the cart until we could wheelie it to ensure we had safe launch airspeed. What WERE they THINKING?)

- 2020/09/19. Oliver Moffatt's VG pops off right after he comes off the pro toad in nothing conditions and he's unable to hold his Moyes Litespeed RX topless topless down and climbs until his BHPA certified AT weak link succeeds three milliseconds before he crashes his trike tug (whose throttle has been stuck wide open. This gives Steve Pearson the perfect opportunity to step in and advertise the critical importance of using VG 0.5 for safe reasonable pitch pressure pro toad aero launches.

Who wants to predict the next mind bogglingly moronic advancement the sport will reveal? I got nuthin'.
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