Weak links

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

Post by Tad Eareckson »

Deltaman - 2013/02/08 13:57:01 UTC

What lacks to your friend Zack is a good understanding of what should be a weaklink..
Its purpose is not to protect the pilot as every ranches are saying but just to protect the glider from overload.
Davis Straub - 2013/02/08 16:57:42 UTC

All the flight parks that I am aware of are quite aware of this. They tell their pilots that the point of the weak link is save the glider from overload and that they should not rely on the weaklink to save them.
Zack C - 2013/02/15 01:53:11 UTC

My only point in posting the video was to demonstrate that weak links cannot prevent attitudes that could be catastrophic near the ground.
Davis Straub - 2013/02/15 02:04:29 UTC

I can't imagine anyone arguing that they would.
Zack C - 2013/02/15 03:14:17 UTC

Whether or not they would argue it, I think many pilots believe it. Just look at the recent post by Daniel Velez about weak links being 'supposed to' break when things are 'a little out of control'. Pilots describe weak links as lockout protectors all the time. I want them to understand how dangerous that line of thinking is.

You have more faith in current aerotow instruction than I.
Jim Rooney - 2013/03/05 21:40:02 UTC

You want MORE.
I want you to have less.
This is the fundamental disagreement.
You're afraid of breaking off with a high AOA? Good... tow with a WEAKER weaklink... you won't be able to achieve a high AOA. Problem solved.

I'm sorry that you don't like that the tug pilot has the last word... but tough titties.
Zack C - 2013/03/06 04:22:08 UTC
Davis Straub - 2013/02/15 02:04:29 UTC

I can't imagine anyone arguing that they would.
Still having trouble imagining, Davis?
Davis Straub - 2013/03/06 18:29:05 UTC

You know, after all this discussion I'm now convinced that it is a very good idea to treat the weaklink as a release, that that is exactly what we do when we have a weaklink on one side of a pro tow bridle. That that is exactly what has happened to me in a number of situations and that the whole business about a weaklink only for the glider not breaking isn't really the case nor a good idea for hang gliding.

I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
Translation (for the really slow reader):

I'm gonna use my Davis/Rooney/Wallaby/Quest/Marzec Link as my sole means of protecting myself and preventing attitudes that could be catastrophic near the ground. (And I strongly encourage everyone else to follow my lead, defer to everything Rooney says, continue giving him free reign to make all of your safety decisions for you, and allow him and his Sacred Fishing Line to act as Pilots In Command of your aircraft).
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Davis Straub - 2013/02/09 16:45:39 UTC

Tug pilots want their weaklink to break if the rope gets caught on some barbed wire.
Fuck the goddam tug "pilots" and what THEY want, Davis. *I* want:

- to fly in the middle of the FAA safety/legal range

- their weak link to be rated in compliance with FAA aerotowing regulations - read: reliably stronger than mine

- to be able to fly through a monster thermal shortly after launch without getting popped off and dumped into a fatal whipstall by the fuckin' idiot tug driver's tow mast breakaway protector

- to have no possibility of getting dumped off by the fuckin' idiot tug driver's tow mast breakaway protector and left with 250 feet of Spectra draped over my basetube waiting to snag on some barbed wire fence on takeoff - which is about fifty times a less manageable, more dangerous, and more likely threat than the bullshit about the tug dying because of an extra couple hundred pounds of front end capability
If you want them to have a stronger weaklink you'll have to talk with them first.
Yeah...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question
Jim Rooney - 2008/11/24 05:18:15 UTC

Well, I'm assuming there was some guff about the tug pilot's right of refusal?
Gee, didn't think we'd have to delve into "pilot in command"... I figured that one's pretty well understood in a flying community.

It's quite simple.
The tug is a certified aircraft... the glider is an unpowered ultralight vehicle. The tug pilot is the pilot in command. You are a passenger. You have the same rights and responsibilities as a skydiver.
It's a bitter pill I'm sure, but there you have it.

BTW, if you think I'm just spouting theory here, I've personally refused to tow a flight park owner over this very issue. I didn't want to clash, but I wasn't towing him. Yup, he wanted to tow with a doubled up weaklink. He eventually towed (behind me) with a single and sorry to disappoint any drama mongers, we're still friends. And lone gun crazy Rooney? Ten other tow pilots turned him down that day for the same reason.
That should be a real productive conversation.
They need to be safe...
OK Davis.

- What's the G rating we use to make it safe for a Dragonfly to drag his towline and carabiner over a barbed wire fence?

- How come...

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.
...that wasn't a concern in the design of the Dragonfly tow system? Or did the double weak link - whatever the hell its strength is - used for the tandem gliders and tail bridle just happen to coincide with the rating which makes it safe for a Dragonfly to drag his towline and carabiner over a barbed wire fence?
...and comfortable...
Yeah Davis, why stop at just safe? Let's make them COMFORTABLE too! Hard to imagine a tug driver being much more safe and comfortable than he is...

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.
...with a weak link (at one end of the towline or other - what's it really matter?) that pops at any little scarcely noticeable irregularity in tension.

And if the tug driver starts getting so safe and comfortable that we can't get any of our gliders off the ground in light morning conditions...

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Davis Straub - 2013/02/09 16:45:39 UTC

We used these with Russell Brown's (tug owner and pilot) approval at Zapata after we kept breaking weaklink in light conditions in morning flights.
...we can always go kiss his ass in hopes that he'll permit us to use something in excess of three quarters of a G.
...as they do a lot more tows than the individual hang glider pilots do.
Yeah Davis...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question
Jim Rooney - 2008/11/22 22:31:35 UTC

Tad loves to speak of himself as a scientifically minded person. Yet he ignores a data pool that is at minimum three orders of magnitude higher than his. It is thus that I ignore him.
http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Jim Rooney - 2011/08/25 21:40:25 UTC

See, the thing is... "we", the people that work at and run aerotow parks, have a long track record.
This stuff isn't new, and has been slowly refined over decades.
We have done quite literally hundreds of thousands of tows.
We know what we're doing.

Sure "there's always room for improvement", but you have to realize the depth of experience you're dealing with here.
We know all about how many tows these assholes pull relative to the number the individual guys who are paying them to get them off the ground get in.

One might think that that would make them - with their purpose built, stable, three axis control, powered aircraft with built in release systems and dump levers on their joysticks pretty proficient at not coming in low enough to snag their towlines on barbed wire fences or being able to jettison them early if they get compromised. But I guess we'd better give them illegally light weak links as well - just in case.

P.S. Any idea what's the ratio of towlines snagged by barbed wire fences to gliders crashed by Davis Links is?

P.P.S. Any thoughts on how we can make things even more dangerous for the gliders in the name of pretending to defuse some other totally bogus threat to the fucking Dragonfly and the asshole driving it?
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

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

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

It was mentioned that pilots have been injured as a result of sudden line release.
HOW DARE anyone mention anything so preposterous! That's totally ridiculous! Everybody knows that the only way you can get hurt behind a tug is...

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

Oh how many times I have to hear this stuff.
I've had these exact same arguments for years and years and years.
Nothing about them changes except the new faces spouting them.

It's the same as arguing with the rookie suffering from intermediate syndrome.
They've already made up their mind and only hear that which supports their opinion.

Only later, when we're visiting them in the hospital can they begin to hear what we've told them all along.
...to sneak in line with a stronglink.
My self, as well as the four other experienced tug pilots watching over my shoulder as I type this, are unaware of anyone who has gotten into trouble as a result of a sudden line release.
Yeah. And a bit under a dozen years from now - and after the 2006/03/15 Advisory...

http://www.ushpa.aero/advisory.asp?id=1
Safety Notice

...USHGA concocted to whitewash the 2005/09/03 - Jeremiah Thompson / Arlan Birkett crash - when Zack Marzec gets killed behind one of your tugs by a standard aerotow weak link blow at 150 feet you pin bending motherfuckers still won't have heard of any pilots being injured as a result of sudden line release.
In fact, a sudden line release would only alleviate any problems a tow pilot may be experiencing.
Of course it will.
Wills Wing / Blue Sky / Steve Wendt / Ryan Voight Productions - 2007/03

NEVER CUT THE POWER...

Image

Reduce Gradually
Increase Gradually
EVERYBODY knows that. Whatever's going on back there...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links
Jim Rooney - 2007/08/01 13:47:23 UTC

Whatever's going on back there, I can fix it by giving you the rope.
...can be fixed by a sudden line release.
Incidents of tug pilots incorrectly chopping power should not be confused with a sudden line release.
You mean the way Dave Farkas did a few seconds before Bill Bennett and Mike Del Signore tip stalled, blew the front end weak link, and slammed in? Yeah, totally different issue.

Fuck all you assholes and the horses you rode in on.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Davis Straub - 2013/03/06 18:29:05 UTC

You know, after all this discussion I'm now convinced that it is a very good idea to treat the weaklink as a release, that that is exactly what we do when we have a weaklink on one side of a pro tow bridle.
Any chance you can walk us through the logic by which you reached that conclusion? 'Cause I was following the discussion and I got the distinct impression that all the folk on that side of it were a bunch of liars, assholes, and morons.
That that is exactly what has happened to me in a number of situations...
Yeah, we've known for decades that the bent pin shit you and your sleazeball buddies market as "releases" is totally useless in situations. How 'bout the PILOTS amongst us who equip ourselves with stuff that DOESN'T stink on ice?
...and that the whole business about a weaklink only for the glider not breaking isn't really the case nor a good idea for hang gliding.
And Davis Pro-Toad Straub and Jim Keen-Intellect Rooney, of course, ARE.
I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
Good. You just keep having those inconveniences now and then. 'Cause you fly a lot and those dice rolls start adding up. And damn near every flight that goes up nowadays has two or three cameras pointed at it.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

This is, in part, a rerun of:

http://www.kitestrings.org/post839.html#p839

but maybe worth some reiteration in this climate of renewed and rabid lunatic insistence that...
Manned Kiting
The Basic Handbook of Tow Launched Hang Gliding
Daniel F. Poynter
1974

"The greatest dangers are a rope break or a premature release." - Richard Johnson
...a rope break is, at worst, an "inconvenience" - and I have got a bit to amend from recent discussions.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=1079
$15 pacifiers
Steve Kinsley - 2005/09/22 00:26:45 UTC

If I had known Tad was going to make one (multi-string emergency release) I would have just waited for his. Although once into it I kinda got hooked on the project. The only real problems in the process were unintended releases but it never really put me in a bad position. I might make an exception for last weekend when I (mis) used Tad's for the first time and ended up dancing on the cart.
Tad Eareckson - 2005/09/22 12:55:24 UTC

The "risks" to which your friendly neighborhood test pilots have been exposing themselves (and the launch crew) have been only ones of inconvenience. The benefits have been the safest and most reliable one and two point systems on the planet.
(I'm still a 130 pound Greenspot zombie at this point in history.)
Jim Rooney - 2005/09/22 14:05:50 UTC

Ok, as long as we're digging this deeply into it....

It is not merely a matter of inconvenience. I was there, and in my oppinion Steve came rather close to breaking his legs. I was getting ready to dial 911.

Sure, being on tow at the wrong time is an extremely bad thing. But don't tell us that being off tow at the wrong time is all sweet and wonderful. Yes, we prepare for it, but that doesn't make it a safe situation. It makes it a manageable situation. There are times where it's better to be on tow than off tow. Ask anyone that's dragged a dolly into the air.

Yes, your tow system failed... it didn't fail to release, it failed to work. Did it fail more safely than a lockout? Yes. But don't tell me that thing worked. You found an unforseen error. That's the problem... unforseen. You don't know what else is waiting for you. Oh, let me rephrase that more accurately, Steve found an unforseen error for you.
Steve Kinsley - 2005/09/26 19:58:19 UTC

I am sure your release works fine and am looking forward to trying it again. I don't think you need to make any changes -- I just have to be smart enough to look and see that I am not holding so much string in my mouth that the shoulder line is loose. I know that. Duh. You can add that to para 1 above. For future reference, if anyone should ever be so bold as to try either of our releases, we need to make sure they understand that.

The actual experience was sort of interesting and in a way amusing. I knew from the first second that it was not doable. Way too much tension. Should have released right then but held on for another couple of seconds until the glider popped off the cart. Thought I was being smart. Got upright and did a half flare. Already congratulating myself for pulling off a good landing under pressure when I felt the cart under my feet. Then I did a little dance trying to push the cart away from me. This part was a crowd pleaser.
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). I tell them the same thing I'm telling you... suck it up. You're not the only one on the line. I didn't ask to be a test pilot. I can live with your inconvenience.
http://groups.yahoo.com/group/hhpa/message/11155
Question
Shane Nestle - 2010/09/17 22:17:50 UTC

So far I've only had negative experiences with weak links. One broke during while aerotowing just as I was coming off the cart. Flared the glider immediately to land and put my feet down in preparation only to find the cart still directly below me. My leg went through the two front parallel bars forcing me to let the glider drop onto the control frame in order to prevent my leg from being snapped.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question
Jim Rooney - 2008/11/22 22:31:35 UTC

The simple fact is this. The only reason anyone even gives Tad the time of day is that they want to believe him. Why? Because they don't like to be inconvenienced by a weaklink break. That's it.

Sure, everyone digs around for other reasons to believe, but at the heart of it, it's convenience.
http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Jim Rooney - 2011/08/28 10:15:12 UTC

Any time someone starts in on this "sole purpose" bullshit, it's cuz they're arguing for stronger weaklinks cuz they're breaking them and are irritated by the inconvenience. I've heard it a million times and it's a load of shit.
Jim Rooney - 2013/03/05 01:32:20 UTC

I want you to have the weakest one practical.. I don't care how much it inconveniences you.
Davis Straub - 2013/02/09 16:45:39 UTC

I can't see how the weaklink has anything to do with this accident.
Zack C - 2013/02/09 17:12:21

You don't think there's even a remote possibility that Zack could have survived had his weak link held?
Davis Straub - 2013/02/09 17:45:21 UTC

I have no idea of the circumstances he faced.
Zack C - 2013/03/05 03:39:52 UTC

This isn't about convenience.
Jim Rooney - 2013/03/05 05:15:25 UTC

Nonsense.
It's completely about convenience.
People like to argue about it and in their arguments, they dig up rationalizations of it not being about convenience, but sorry... it very much is about convenience.

Take if from the other angle... if it were about safety... if you are truly concerned about your safety... why are you towing? Why are the people that are arguing about weaklinks towing?
The answer of course is that it's not actually about "safety".

People get pissed off not because the weaklink breaking made their lives scary... it made it a pain in the ass. They missed the thermal. They had to relight. Etc.
I'm not saying that these are invalid feelings.
I'm saying that they're not about safety.
Zack C - 2013/03/05 15:16:23 UTC

Yes, this is very much about safety. What happened at Quest last month has only reinforced my position.

All of that said, weak link breaks are rarely more than an inconvenience. But there's no sensible reason to expose ourselves to the increased risk, however small.
Jim Rooney - 2013/03/05 19:42:58 UTC

Wow...
So you know what happened then?
OMG... thank you for your expert accident analysis. You better fly down to FL and let them know. I'm sure they'll be very thankful to have such a crack expert mind on the case analyzing an accident that you know nothing about. Far better data than the people that were actually there. In short... get fucked.

Again, tell me how all this nonsense is about "safety"?
Davis Straub - 2013/03/06 18:29:05 UTC

I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
Zack C - 2013/03/06 21:37:38

I never had a serious problem with it either. But I've seen enough evidence that I'm not going to wait until I do.
So when somebody comes back down on the cart as a consequence of a Rooney Link pop it's a mere inconvenience.

But if somebody misuses an item of homemade gear - from Tad's home - and gets it to do what it's supposed to do at an inopportune time and has a close encounter with a cart that's a barely avoided ambulance ride, it's COMPLETELY unacceptable, and cause for permanent grounding.

And when somebody whipstalls and dies during the ambulance ride due to a Rooney Link pop...
Jim Rooney - 2013/03/05 21:40:02 UTC

You're afraid of breaking off with a high AOA? Good... tow with a WEAKER weaklink... you won't be able to achieve a high AOA. Problem solved.
...the Rooney Link couldn't POSSIBLY be the problem and the OBVIOUS solution is to use a less convenient piece of fishing line.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=1079
$15 pacifiers
Jim Rooney - 2005/09/22 14:05:50 UTC

Sure, being on tow at the wrong time is an extremely bad thing. But don't tell us that being off tow at the wrong time is all sweet and wonderful. Yes, we prepare for it, but that doesn't make it a safe situation. It makes it a manageable situation.
BULLSHIT.

- To say that any situation in aviation is unsafe but "manageable" is absolute rot.

- We survive or die by the whims of Mother Nature - and anybody who believes otherwise is a testosterone poisoned asshole in desperate need of another hobby as far removed from Mother Nature as possible.

- We best survive by developing a reasonably good understanding of Mother Nature and staying the fuck out of situations in which there's a fair possibility of her exercising her superiority.

- If/When we blunder into a situation in which she's exercising her superiority what was normally "manageable" is very likely to rapidly become unmanageable.

- Therefore - a PILOT really isn't interested in what's "manageable". He's interested in the widest safety margins and as much control over the situation as possible.

- And Industry Standard equipment - especially Industry Standard pro toad equipment and Rooney Links - do NOTHING but narrow safety margins and rob the PILOT of control over the situation.

You sleazy motherfuckers can maintain this farce that this was an inexplicable freak accident in no way related to this chintzy piece of fishing line you've been forcing everyone up on all you want. But the undeniable facts remain that:

- There was an unusual but predictable and precedented thermal break shortly after launch.

- The pilot's ability to react to it was diminished by his having opted to be pro toad.

- Despite this reduction in safety margin the pilot was able to manage the situation as long as he was able to execute his own decisions.

- The INSTANT his Davis/Rooney executed its decision to clearly limit the angle of attack the angle of attack went through the ceiling and the situation became unmanageable, unsustainable, unrecoverable, and unsurvivable.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Zack C - 2011/08/26 03:54:21 UTC

Jim,

Before I respond, what do you advocate as an appropriate weak link strength for aerotowing and why? Thanks.
Jim Rooney - 2011/08/26 06:04:23 UTC

I get what you're saying Christopher.
Please understand that I'm not advocating professional infalliblity. Not really sure where I mentioned that, but I can understand where you might have drawn that assumption. None the less, I simply refer to "us" as the "professional pilots" as a term to describe the pilots that do this for a living. Yes, we're just humans... bla bla bla... my point is that we do this a whole sh*tload more than the "average pilot"... and not just a little more... a LOT.

We discuss this stuff a lot more as well. We vet more ideas. This isn't just "neat stuff" to us... it's very real and we deal with it every day.

It's not "us" that has the track record... it's our process.
We're people just like anyone else. And that's the point. THIS is how we do it... normal, fallible humans... and it bloody well works.
But...

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Zack C - 2013/02/13 15:02:38 UTC

Can you explain, then, exactly how we arrived at the current 130 lb weak link standard?
Jim Rooney - 2013/02/13 19:09:33 UTC

It was already worked out by the time I arrived.
So, obviously, when you tell us all about how much you discuss this stuff and vet ideas you're LYING. The reason you use it is because it's the first and last thing Bobby pulled out of his ass, it's sometimes capable of getting gliders to altitude one out of four of five flights on a moderate day, and you don't give a rat's ass how many gliders it crashes because the tug's always in better shape when a glider pops off.
So I don't give much credence to something that someone doesn't agree with about what we do for some theoretical reason.
Of course you don't. You just go with what the biggest number of idiots are doing because it's hard to get in trouble that way - as long as your ass is safely strapped into a Dragonfly anyway.
Take this weaklink nonsense.
What do I "advocate"?
We covered that already.
I don't advocate shit... I *USE* 130 test lb, greenspun cortland braided fishing line.
It is industry standard.
It is what *WE* use.
And whenever somebody does anything different...

http://ozreport.com/9.032
The Worlds - weaklinks
Davis Straub - 2005/02/07

For a couple of years I have flown with a doubled weaklink because, flying with a rigid wing glider, I have found that there is little reason to expect trouble on tow, except from a weaklink break.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=242
VOX
Paul Tjaden - 2005/03/12 14:54:17 UTC

I noticed that Jim Lamb uses two barrel releases and NO weak link.
http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Rooney - 2013/02/15 06:48:18 UTC

AP flies in OZ
I have no clue what they're using over there.
Jim Rooney - 2013/02/15 06:48:18 UTC

Naw.
Davis has been at an around all this plenty long enough to understand what's what and who's who.
...they get eliminated from the category of "*WE* - and any data associated with their flying gets flushed down the toilet.
If someone's got a problem with it... we've got over ONE HUNDRED THOUSAND TANDEM TOWS and COUNTLESS solo tows that argue otherwise. So they can politely get stuffed.

As my friend likes to say... "Sure, it works in reality... but does it work in theory?"
Hahahahhaa... I like that one a lot ;)
Steve Davy - 2011/08/26 07:35:07 UTC
Zack C - 2011/08/26 03:54:21 UTC

Jim,

Before I respond, what do you advocate as an appropriate weak link strength for aerotowing and why? Thanks.
Is this an "actual" question?
Jim Rooney - 2011/08/26 08:24:31 UTC

Thought I already answered that one... instead of quoting myself (have a look back if you don't believe me), I'll just reiterate it.

I don't advocate anything.
I use what we use at the flight parks. It's time tested and proven... and works a hell of a lot better than all the other bullshit I've seen out there.
- Sounds like you're advocating it to me.

- Can you describe what it works better to a hell of a lot better than all the other bullshit you've seen out there? Mike Haas, Steve Elliot, and Roy Messing were locked out and killed on it and Zack Marzec was whipstalled and killed on it and Dick Reynolds, Frank Murphy, and an unidentified Dragonfly in Ontario were stalled and seriously crashed on it. What's all the other bullshit you've seen out there not worked to do and what have the results been?
130lb greenspot (greenspun?) cortland fishing line.
In stock at Quest, Highland, Eastern Shore, Kitty Hawk Kites, Florida Ridge, and I'm pretty sure Wallaby, Lookout and Morningside.
Not sure what Tracy up at Cloud Nine uses, but I'll put bets on the same.
Of course he does...
Dr. Trisa Tilletti - 2012/06

Based on several decades of experience and hundreds of thousands of tows conducted by numerous aerotow operators across the county, the de facto standard has become use of a 260 lb. weak link made as a loop of 130 lb. green spot IGFA Dacron braided fishing line attached to one end of the pilot's V-bridle.
All you assholes are totally excellent at blindly mimicking whatever you see other assholes doing.
Did I miss any?
Campbell Bowen, who was flying a double loop of 130 on a one point bent pin configuration until I set him up with one of my assemblies...

http://www.flickr.com/photos/aerotowrelease/8313526097/
Image

...at the 2008 ECC with a couple of Bridle Links in the ballpark of four hundred pounds.
Is it clear what I mean by "We"?
Yeah. A bunch of stupid sheep who have no fuckin' clue what they're doing and are capable only of going along with the herd safely back from anything remotely resembling a lead.
I didn't make the system up.
No, we've already established that it was just something Bobby pulled out of his ass.
And I'm not so arrogant to think that my precious little ideas are going to magically revolutionise the industry.
Why not?

http://ozreport.com/forum/viewtopic.php?t=22660
What can be learned from this "scooter" towing accident?
Mitch Shipley - 2011/01/31 15:22:59 UTC

Enjoy your posts, as always, and find your comments solid, based on hundreds of hours / tows of experience and backed up by a keen intellect/knowledge of the issues when it comes to most things in general and hang gliding AT/Towing in particular. Wanted to go on record in case anyone reading wanted to know one persons comments they should give weight to.
Who better to be so arrogant as to think that his precious little ideas are going to magically revolutionize The Industry?
There are far smarter people than me working this out.
I know, I've worked with them.
That's not what you said at the time...
Jim Rooney - 2011/01/31 19:16:54 UTC

Hi Mitch!
Welcome to the circus :)

For those who don't know Mitch... in addition to many other hats (including sub commander and professor)... he's an instructor at Quest Air. He's got a very level head and is a good friend.
You were so arrogant as to accept the designation and reciprocated with a few strokes of Mitch's dick. You didn't say, "Thanks Mitch, but I'm a mere insect compared to a fucking genius like Bobby Bailey. And if anyone truly values his life he's the one person who's comments should be given the most weight.
(Bobby's a fucking genius when it comes to this shit... for example.)
Yeah?

http://ozreport.com/3.066
Weaklinks
Davis Straub - 1999/06/06

During the US Nationals I wrote a bit about weaklinks and the gag weaklinks that someone tied at Quest Air. A few days after I wrote about them, Bobby Bailey, designer and builder of the Bailey-Moyes Dragon Fly tug, approached me visibly upset about what I and James Freeman had written about weaklinks. He was especially upset that I had written that I had doubled my weaklink after three weaklinks in a row had broken on me.
Bobby's too fucking stupid to be able to figure out that:

- a double loop of 130 on a solo glider presents no more danger to the tug than it does on a tandem

- a glider's weak link doesn't override what the tug's using

- if you:

-- use a double loop of 130 on a tandem glider's bridle and the tug's bridle the tandem will get the rope about half the time

-- engineer the tow mast to break away at the same tension as the front end weak link which is the same tension as the back end weak link the tow mast, front end weak link, and back end weak link all have pretty even odds of failing when things get loaded up a bit

- that if you:
-- don't want the tow mast breakaway to break away every third time you'll need to dumb down the front end weak link
-- dumb down the front end weak link it's a really bad idea to leave the back end weak link as high as it was

And...

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). I tell them the same thing I'm telling you... suck it up. You're not the only one on the line. I didn't ask to be a test pilot. I can live with your inconvenience.
...you're every bit as fucking stupid - and then some.
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Tad Eareckson
Posts: 9150
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/3.066
Weaklinks
Davis Straub - 1999/06/06

During the US Nationals I wrote a bit about weaklinks and the gag weaklinks that someone tied at Quest Air. A few days after I wrote about them, Bobby Bailey, designer and builder of the Bailey-Moyes Dragon Fly tug, approached me visibly upset about what I and James Freeman had written about weaklinks. He was especially upset that I had written that I had doubled my weaklink after three weaklinks in a row had broken on me.

I told him that I would be happy to publish anything that he wrote about weaklinks, but I never received anything from him or anyone else at Quest.
Highland Aerosports - 2011/07/27

With the loss of our dear friend and tug pilot Keavy Nenninger, we will be closed over, at least, the next week (updated 7/27). We apologize for any inconvenience, but we need time to pay respects to her family and do some grieving of our own. Please be patient as we won't likely be returning calls or emails until we re-open. For those who have been contacting us offering help and support... Thank you! Keavy constantly commented on something we already knew, just how wonderful the hang gliding community is. Thanks for your patience.
http://ozreport.com/forum/viewtopic.php?t=24534
It's a wrap
Lauren Tjaden - 2011/08/01 02:01:06 UTC

For whomever asked about the function of a weak link, it is to release the glider and plane from each other when the tow forces become greater than desirable -- whether that is due to a lockout or a malfunction of equipment or whatever. This can save a glider, a tow pilot, or more often, a hang glider pilot who does not get off of tow when he or she gets too far out of whack.
http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Jim Rooney - 2011/08/25 04:55:25 UTC

It always amazes to hear know it all pilots arguing with the professional pilots.
I mean seriously, this is our job.
We do more tows in a day than they do in a month (year for most).

We *might* have an idea of how this stuff works.
They *might* do well to listen.
Jim Rooney - 2011/08/26 08:24:31 UTC

I didn't make the system up.
And I'm not so arrogant to think that my precious little ideas are going to magically revolutionise the industry.
There are far smarter people than me working this out.
I know, I've worked with them.
(Bobby's a fucking genius when it comes to this shit... for example.)
Steve Davy - 2011/08/28 07:03:15 UTC

http://www.dynamicflight.com.au/WeakLinks.html
Jim Rooney - 2011/08/28 08:34:12 UTC

Yeah, I've read that drivel before.
It's a load of shit.
Davis Straub - 2011/08/28 15:26:28 UTC

Then again, Russell Brown had us double up behind him after six breaks in a row at Zapata. We couldn't figure out why we had so many breaks so quickly. Maybe just coincidence.
Dr. Trisa Tilletti - 2012/06

Russell Brown, a founder of Quest Air in Florida and a well-known Dragonfly tug pilot, is also a sailplane pilot, tug pilot, and A&P mechanic for a large commercial sailplane towing operation in Florida. He told us that, like us, he has never seen a sailplane weak link break, either.
http://www.hanggliding.org/viewtopic.php?t=26870
weak links
Davis Straub - 2012/08/13 18:08:42 UTC

Used to do 130 lbs. Now do 200 lbs.
http://www.hanggliding.org/viewtopic.php?t=27393
Pro towing: 1 barrel release + weak link or 2 barrel release
Juan Saa - 2012/10/18 01:19:49 UTC

The normal braking force in pounds for a weak link is around 180, at least that is the regular weak link line used at most aerotow operations. By adding a second weak link to your bridal you are cutting the load on each link by half, meaning that the weak link will not break at the intended 180 pounds but it will need about 360.
If that is what you use and is what your instructor approved then I have no business on interfering, i dont know if you are using the same weak link material but there shoul be only ONE weak link on a tow bridle for it to be effective in breaking before higher loads are put into you and the glider should the glider gets to an attitude or off track so much that the safety fuse of the link is needed to break you free from the tug.
I made the same mistake on putting two weak links thinking that I was adding protection to my setup and I was corrected by two instructors on separate occacions at Quest Air and at the Florida RIdge.
http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Rooney - 2013/02/15 06:48:18 UTC

AP flies in OZ
I have no clue what they're using over there.
Jim Rooney - 2013/02/15 06:48:18 UTC

Naw.
Davis has been at an around all this plenty long enough to understand what's what and who's who.
Deltaman - 2013/02/16 22:41:36 UTC

How is that possible to write so much ..and say NOTHING !?

As far as I can see, his position can be boiled down to 'we use this because this is what we use.' And somehow asserting this constitutes 'refuting' something...
Jim Rooney - 2013/02/16 23:18:54 UTC

Naw... You want me to make bold black and white statements so that you can have a go.
Unfortunately that's not what you're getting.
http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Jim Rooney - 2013/03/11 18:59:06 UTC

Why aren't straight pins used?
That's easy. They can't be used with anything but thin lines.
They also can't be made with anything but thin lines.
Jim Rooney - 2013/03/11 18:59:06 UTC

Tad loves to forget that I've actually gotten one of his to jam.
Hey Jim,

This lunacy is all over the goddam map.

If Bobby's such a fucking genius when it comes to this shit, how come he doesn't just step in and explain to all us muppets...
- why:
-- double loops endanger the tug when they're on solos but not tandems
-- the hell Keavy Nenninger's Dragonfly fell out of the sky and killed her
- how far out of whack a standard aerotow weak link allows one to get
- the experimental process used to select 130 pound Greenspot as the optimal lockout protector for all solo gliders
- why Dynamic Flight's advocacy of the weak link as a load limiter is a load of shit
- how insanely dangerous it was for:
-- Russell to double up the optimal solo lockout protector after blowing six in a row
-- Morningside to go 54 percent in one hop rather than nine six percent experimental increments
- how dangerous it is to use weak links on BOTH ends of a one point bridle
- what they're using in Oz
- the proper multiplier for someone who's been at an around all this plenty long enough to understand what's what and who's who
- how:
-- it's possible for you to write so much and say NOTHING
-- to best:
--- avoid any hint of a bold black and white statement regarding any towing equipment towing
--- rig your equipment to get it to malfunction

We've all bought the fucking genius's tugs, releases, and weak links and spent tens of thousands of hours discussing Bailey equipment induced fatalities so why can't the motherfucker lend us just a wee tiny bit of his fucking genius to get us all set on the right track?

Einstein figured out relativity and was able to explain it in terms some of us muppets could understand.

- Is Bobby and his understanding of hang glider aerotowing so far above Einstein's level that there's just no fuckin' way he can dumb things down enough for glider people to really understand 130 pound Greenspot?

- Doesn't he have an OBLIGATION to help us out so we don't kill even more people straying from the path he so carefully established?

- What the hell is so useful about being a fucking genius if it's impossible for anyone else to benefit from it?

Somebody find me ONE WORD from any hang gliding archives ANYWHERE that Bobby Fucking-Genius Bailey has typed, penned, penciled, crayoned, or finger-painted.
User avatar
Tad Eareckson
Posts: 9150
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

I know I've beaten this one up plenty before but it's so massively freaking relevant to the 2013/02/02 lethal clusterfuck at Quest that I just can't resist taking another shot. Might even be able to get a few new digs in...
Dennis Pagen - 2005/01

SUMMER 2004 ACCIDENT REPORTS

Recently two unrelated hang gliding accidents occurred in Europe, which may have some lessons for us. I had flown with and knew both pilots. My descriptions and analysis are based on eyewitness reports in the first case and the fact that I witnessed and talked at great length to the pilot as well as examined the wreckage in the second case.

FATAL TOWING ACCIDENT

The first accident occurred in Germany at an aerotowing competition. The pilot launched with his Litespeed and climbed to about forty 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. In addition, there were hangars and trees on the left, which is the way the glider was tending. By the time we gained about sixty feet I could no longer hold the glider centered--I was probably at a twenty-degree bank--so I quickly released before the lockout to the side progressed. The glider instantly whipped to the side in a wingover maneuver. I cleared the buildings, but came very close to the ground at the bottom of the wingover. I leveled out and landed.

Analyzing my incident made me realize that had I released earlier I probably would have hit the ground at high speed at a steep angle. The result may have been similar to that of the pilot in Germany. The normal procedure for a tow pilot, when the hang glider gets too high, is to release in order to avoid the forces from the glider pulling the tug nose-down into a dangerous dive. This dangerous dive is what happened when Chris Bulger (U.S. team pilot) was towing John Pendry (former world champion) years ago. The release failed to operate in this case, and Chris was fatally injured. However Neal kept me on line until I had enough ground clearance, and I believe he saved me from injury by doing so. I gave him a heart-felt thank you.

The pilot in the accident under discussion was an aerodynamic engineer. He had altered his glider by lengthening the front cables and shortening the rear cables to move his base tube back. The amount was reportedly ten centimeters, or about four inches. This is well within the acceptable range, according to Gerolf Heinrichs, the Litespeed designer. Why the pilot altered his bar position in this manner is anyone's guess, but my guess is that it was because he felt the bar was too far out on the glider with the VG off. This Litespeed was the pilot's first topless glider and I expect he wasn't informed that most of the new topless gliders experience a great movement of the base tube as the VG is pulled through its range. The result is that the bar is so far out and the pitch pressure so strong that with the VG off, that the standard procedure is to take off and land with at least a quarter VG. If the pilot didn't know this he would have been tempted to move the bar.

Factors that attributed to the accident in various degrees were the pilot's experience, the conditions and the alteration of the base tube. To begin, he wasn't greatly experienced in aerotowing, although he had learned and spent much of his flying with surface tow. It is difficult to assess the effect of the turbulence, but suffice it to say that it was strong enough to project him upward, well above the tug. Finally, the alteration of the basetube position could have been a contributing factor because he certainly would have had more pitch authority if he hadn't done that. It is impossible to tell, but perhaps the thermal that lifted him would not have done so as severely if he had had a bit more pitch travel.

What We Can Learn

To begin, alteration of our gliders should not be done without full agreement and guidance from the factory or their trained representatives. Even with such approval, be aware that the factory might not know how you will be using your equipment. Changing the pitch range of a glider is a fairly serious matter and should only be done with full understanding of all the effects.

Secondly, over-the-top lockouts are not frequent, but common enough in big-air towing that tow pilots should all have a plan to deal with them. Think about this: When we are lifted well above the tug, the tow system forces becomes similar to surface towing, with the limit of tow force only being the weak link. The susceptibility to a lockout is increased in this situation.

My experience leads me to believe that a strong thermal hitting when low can push you vertically upwards or sideways before you have time to react. If this happens when I am low, I fight it as hard as I can until I have clearance to release safely. If I am high above the tug, I stay on line with the bar pulled in as far as possible and keep myself centered if at all possible. I fully expect the tug pilot to release from his end if necessary for safety, but in the case of a malfunction, I would release before endangering the tug.

We are taught to release at the first sign of trouble, and I fully support that general policy, but in some cases, the trouble happens so fast and is so powerful that a release low would have severe consequences. In my case, I was instantly high above the tug with a strong turn tendency and a release at that point would have been ugly. The main point for us to understand is that we must gain our experience in gradually increasing challenges so we can respond correctly when faced with different emergencies. It should be made clear again that a weak link will not prevent lockouts and a hook knife is useless in such a situation, for the second you reach for it you are in a compromised attitude.

Thirdly, experienced pilots should be aware that towing only from the shoulders reduces the effective pull-in available to prevent an over-the-top lockout. Like many pilots, I prefer the freedom of towing from the shoulders, but I am aware that I must react quicker to pitch excursion. Sometimes reactions aren't quick enough and emergency procedures must be followed. It seems to me that we shouldn't be overly eager to encourage lower airtime pilots to adopt this more advanced method of aerotowing. Normally, we tow topless gliders with about a third VG pulled to lighten pitch forces and increase speed. Intermediate gliders are often towed as much as half VG pulled for the same reasons. Pilots must understand these matters when aerotowing.

Finally, I think it is appropriate to remind all dealers, instructors and pilots in general to inform their customers and friends that the new topless gliders exhibit the notable bar movement with VG travel as explained above. As such, it is normal to take off and land with a quarter VG on in order to place the bar in a position to roll easier and to reduce the pitch pressure. It is much easier to maintain safe control speed with the VG pulled a quarter.
Recently two unrelated hang gliding accidents occurred in Europe, which may have some lessons for us.
Bullshit. If somebody has an AT rating there shouldn't be a goddam thing to learn from any of these.
FATAL TOWING ACCIDENT
Fatal towing WHAT?
The first accident occurred in Germany...
Where the fuckin' idiot DHV assholes have...

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Kai-Martin Knaak - 2013/02/12 00:54:02 UTC

DHV homologated tow set-ups put the weak link directly in the tow line. So the German links break at up to thirty percent smaller forces than what was used in the accident.
...absolutely PATHETIC weak link limitations.
...at an aerotowing competition.
Was Davis running it?
The pilot launched with his Litespeed and climbed to about forty feet when he encountered a thermal that lifted him well above the tug.
- WHOA!!! At an aerotow competition? Who could've seen something like THAT coming!
- So how come:
-- the ribbons they had along the runway didn't tip anyone off?
-- he wasn't able to hold it down? Was the trim point on the keel appropriate for the speed at which he was being towed?
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...
Why?

- Did he think he could fix a bad thing and didn't want to start over?

- Or was he flying some piece of shit release that...
Towing Aloft - 1998/01

The towline release is a critically important piece of equipment. It is the device which frees you from the towline and it must be failure-proof. Numerous designs have evolved over the years--some very good and some not so good. Unfortunately, releases are items that many pilots feel they can make at home or adapt from something they have seen at the hardware store. Two fatalities have occurred in the past five years directly related to failures of very poorly constructed and maintained releases. For the sake of safety, only use releases that have been designed and extensively tested by reputable manufacturers.
...he made at home and proved totally useless when the shit hit the fan?
...in a classic lockout maneuver.
I got news for ya, Dennis... A lockout is NOT...
maneuver
- a movement or series of moves requiring skill and care
- a carefully planned scheme or action
...a MANEUVER. It's actually a TOTAL INABILITY to maneuver.
The impact was fatal.
Probably using one of those salad bowl on a string helmets.
Analysis
We don't really need one, Dennis. This ain't rocket science. What we NEED are the ribbons to help avoid these situations and the bridles, releases, and weak links to give us the ability to best deal with the shit we can't. So how 'bout signing the fuck off of this piece of shit magazine and make way for some articles on equipment that doesn't originate from the slimeball outfits which told you what they did and didn't want in your book to lull all of their students into false senses of security?
This pilot was a good up-and-coming competition pilot.
- Really? Doesn't sound like he was good enough to start a task very successfully. How do you think a mediocre one would've done?
- And he didn't have a name and we can't have a date or location?
- Is it worth telling us what he was using for a bridle, release, and weak link? Or were those bits of trivia deemed of no significance relevance?
He had been in my cross-country course three years ago, and this was his second year of competition.
Did you discuss anything about how to get safely airborne in thermal conditions? No, wait. He probably had a copy of the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden. So why bother? Everything's pretty thoroughly covered in there.
What happened to him is not too unusual or mysterious.
- Yeah, nothing too unusual or mysterious. Hang Four level XC comp pro toad hooks up behind a tug, hits a thermal, locks out, can't release, tug driver fails to make a good decision in the interest of his safety, Rooney Link fails to very clearly provide protection from excessive angles of attack, high bank turns, and the like for that form of towing, glider slams in still on tow, OK, next up...

- But fuck, it really wasn't worth putting anything in your book about it or publishing anything in the magazine about how we needed to address this issue before it killed someone - again.
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.
Really? Are you SURE that he had a proper trim point on his keel? Maybe it was back a couple of inches more than it should've been.
This situation is known as an over-the-top lockout.
An over-the-top lockout? Are you SURE? I looked all through the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden, and couldn't find a single mention of such a thing.
I am personally familiar with such a problem, because it happened to me at a meet in Texas.
Whoa dude! Seems like these things really AREN'T too unusual or mysterious. So what happened to the chapter in the book that tells us how to deal with them? Did the printer mess up or something?
Soon after lift-off the trike tug and I were hit by the mother of all thermals.
Whoa dude! Something like that just happened at Quest nine weeks and a couple of days ago these things seem to be getting less unusual and mysterious all the time!
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.
Well Mark Frutiger was on a Dragonfly and he knew it was some pretty solid lift but not all that big a fuckin' deal - nothing that he hadn't hit and towed gliders through before.

Zack Marzec's glider - a Litespeed as a matter of fact - was 255 pounds, about the same flying weight as you, and it also started rocketing up. But he was using a standard aerotow weak link which very clearly provided him protection from an excessive angle of attack for that form of towing so he didn't continue to rocket up for all that long.

By the way... I don't recall what it was that you said YOU were using for a weak link. But last time I saw you at Ridgely it was a single loop of 130 pound Greenspot on one end of your single-point bridle. Any thoughts on why you were able to continue rocketing up while he was so very clearly and quickly provided protection from an excessive angle of attack for that form of towing?
I pulled in all the way, but could see that I wasn't going to come down unless something changed.
I'll bet you were really hoping your standard aerotow weak link would very clearly provide you protection from an excessive angle of attack for that form of towing at that point. Zack's worked flawlessly for him, things changed right away, and he came right down like a fuckin' brick.
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.
Think maybe Zack might ALSO have been trying to hang on and resisting the tendency to roll to the side with the bar at HIS knees? There are a lot of people in the postmortem discussions who seem to think he was pushing out.
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.
But you'd have been just fine if your standard aerotow weak link had very clearly provided you protection from an excessive angle of attack for that form of towing. Because a weak link - unlike a premature release - ALWAYS increases the safety of the towing operation.

What do you believe Zack Marzec didn't want to do when he was in the same situation and for what reasons?
In addition, there were hangars and trees on the left, which is the way the glider was tending.
Zack was in the clear - so he was probably hoping for his standard aerotow weak link to function as an instant hands free release.
By the time we gained about sixty feet I could no longer hold the glider centered--I was probably at a twenty-degree bank--so I quickly released before the lockout to the side progressed. The glider instantly whipped to the side in a wingover maneuver.
Oh. So you had the bar to your knees while standing on your tail and locking out to the side and when you took one hand off to blow your bent pin barrel release the glider instantly whipped to the side in a wingover maneuver.

Wow. I don't know how I managed to read the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden, and not pick up on that as a potential issue.
I cleared the buildings, but came very close to the ground at the bottom of the wingover.
- Kinda like THIS:

http://www.youtube.com/watch?v=F_n5B3-MIC4

11-1814
Image
12-1915
Image
13-2008
Image

'cept a few feet higher?

- In other words, you deviated from your original flight plan a little and went into passenger/luck mode for a while.
I leveled out and landed.
So did Zack...

http://4.bp.blogspot.com/-bRrpHNa68iY/UQ6Pv9gRZyI/AAAAAAAAjTg/Hc22bx5122Q/s2048/20943781_BG1.jpg
Image

But first he tailslid, whipstalled, and tumbled a couple of times. And his landing was a little harder than yours - and MG's.
Analyzing my incident made me realize that had I released earlier I probably would have hit the ground at high speed at a steep angle.
- Did analyzing your incident also make you realize that had your standard aerotow weak link very clearly provided you protection from an excessive angle of attack for that form of towing earlier you probably would also have hit the ground at high speed at a steep angle?

- Any thoughts on how Zack was analyzing his incident while it was in progress, assessing his situation, and determining a best course of action?
The result may have been similar to that of the pilot in Germany.
Or, perhaps, the pilot at Groveland, Florida.
The normal procedure for a tow pilot, when the hang glider gets too high, is to release in order to avoid the forces from the glider pulling the tug nose-down into a dangerous dive.
- Who defined that "normal procedure", motherfucker?

- Has anyone ever recorded an incident of a high glider pulling a tug nose-down into a dangerous dive?

-- MG's trike seems to be doing OK.

-- Zack Marzec's Dragonfly...

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.
...didn't seem to be terribly inconvenienced at the point his standard aerotow weak link very clearly provided him protection from an excessive angle of attack for that form of towing.
This dangerous dive is what happened when Chris Bulger (U.S. team pilot) was towing John Pendry (former world champion) years ago.
- 1985/07/17.
- Bullshit.
The release failed to operate in this case, and Chris was fatally injured.
Goddam right. They were in smooth air, everything was going fine until Chris decided to get cute, the release was a total piece of shit, Chris wasn't securely strapped in, and the parachute was still in the truck. That clusterfuck has no relevance to ANYTHING.
However Neal kept me on line until I had enough ground clearance, and I believe he saved me from injury by doing so.
How very brave of him to do just do nothing while you maxed out control of your situation. Rob Richardson should've been so lucky.
I gave him a heart-felt thank you.
Sounds like a real bad idea, Dennis. How do you know that reinforcing negative behavior like that...
Towing Aloft - 1998/01

Pro Tip: Always thank the tug pilot for intentionally releasing you, even if you feel you could have ridden it out. He should be given a vote of confidence that he made a good decision in the interest of your safety.
...won't make him less likely to make a good decision in the interest of the safety of the next guy?

To be continued...
User avatar
Tad Eareckson
Posts: 9150
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

Dennis Pagen - 2005/01

The pilot in the accident under discussion was an aerodynamic engineer.
Obviously not a very good one if he hadn't figured out that:

- a towed hang glider is roll unstable

- you:

-- need two hands on the basetube at all times to fly a hang glider

-- especially need two hands on the basetube at all times to fly a towed hang glider

-- REALLY especially need two hands on the basetube at all times to fly a towed locking out hang glider

-- really need to have a release which allows you to blow tow with both hands on the basetube if you don't wanna have a fair chance of winding up like many dead guys from a long history of hang glider towing lunacy

-- need a bridle attachment on the keel to keep the glider in safe trim when it's being towed from straight ahead

- anybody who aerotows under the idiot fucking DHV's idiot fucking weak link limits is out of his idiot fucking mind
He had altered his glider by lengthening the front cables and shortening the rear cables to move his base tube back. The amount was reportedly ten centimeters, or about four inches.
Sure, why not? Hard to imagine anyone ever needing those last four inches of pitch control range for which the glider was certified - especially a pro toad flying under the idiot fucking DHV's idiot fucking weak link limits.
This is well within the acceptable range, according to Gerolf Heinrichs, the Litespeed designer.
Of course it is. Just look at how great everything turned out.

And I'll bet flying upright with one's hands on the downtubes gives one an acceptable degree of control on a landing approach.

Bull fucking shit dudes. "ACCEPTABLE" is a relative term in aviation. And if you're giving something up there sure as hell better be something pretty good you're getting back in return for it. And I'm not seeing it here.
Why the pilot altered his bar position in this manner is anyone's guess, but my guess is that it was because he felt the bar was too far out on the glider with the VG off. This Litespeed was the pilot's first topless glider and I expect he wasn't informed that most of the new topless gliders experience a great movement of the base tube as the VG is pulled through its range.
What's the big fucking deal here? Didn't Gerolf JUST SAY what he did was "acceptable"?
The result is that the bar is so far out and the pitch pressure so strong that with the VG off, that the standard procedure is to take off and land with at least a quarter VG. If the pilot didn't know this he would have been tempted to move the bar.

Factors that attributed to the accident in various degrees were the pilot's experience, the conditions and the alteration of the base tube.
So one of the factors that got him killed was "acceptable". Like a lockout...
...in a classic lockout maneuver.
is a "maneuver". And...
Towing Aloft - 1998/01

With a two-point bridle, the pull on your shoulders is reduced so the pressure changes are subtle. You can watch the towline--which will have a bow or belly due to its weight, despite the tow force--to get clues as to when the tow forces are increasing or decreasing.
...tow TENSION is "PRESSURE". This is hang gliding so you can just assign whatever meanings to words you feel like.

Works great with time intervals too - "just prior to launch" averages out to something like five or ten minutes.
To begin, he wasn't greatly experienced in aerotowing...
But if he had been he'd have been able to stuff the bar - towing off his shoulders and with the modified rigging - just fine.
...although he had learned and spent much of his flying with surface tow. It is difficult to assess the effect of the turbulence, but suffice it to say that it was strong enough to project him upward, well above the tug.
That was "TURBULENCE" that shoved him up well above the tug? Funny, I thought...
The pilot launched with his Litespeed and climbed to about forty feet when he encountered a thermal that lifted him well above the tug.
...it was a THERMAL. But I guess it works better if it's turbulence now because everyone knows:
- thermals are good things and the only reason we tow
- turbulence is bad shit in which anything bad can happen
and nobody wants to believe that he can get killed by a thermal on aerotow.
Finally, the alteration of the basetube position could have been a contributing factor because he certainly would have had more pitch authority if he hadn't done that.
No fuckin' way dude. That's already been ruled "acceptable".
It is impossible to tell, but perhaps the thermal that lifted him would not have done so as severely if he had had a bit more pitch travel.
Yeah Dennis. It's just fuckin' IMPOSSIBLE to tell. 'Cause if it were POSSIBLE to tell that would make:

- "PRO TOWING" *DANGEROUS*

- the tow park people a bunch of negligent pieces of shit for telling their marks that it's something that can be managed by pilots with sufficient SKILL levels

- the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden a load of dangerous crap

Sleazy goddam motherfuckers.

To be continued...
Steve Davy
Posts: 1338
Joined: 2011/07/18 10:37:38 UTC

Re: Weak links

Post by Steve Davy »

Tad Eareckson wrote:Zack Marzec's glider - a Litespeed as a matter of fact...
The report says that Zack was flying a Moyes Xtralite.
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