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 »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Brad Gryder - 2013/03/06 03:33:45 UTC

Zack, sorry for the delayed response, but I had to do some work and I'm just now able to dive back into this here furball.
That's alright, Brad. We have enough lunatic crap posted by enough other total assholes to keep us backed up for the next ten years. I'm taking you way out of turn because this one is such a gem.
New bumper sticker - "I'd rather be dog fighting".
I'd rather you whipstall back into the runway like Zack Marzec did 'cause it's really hard for most of the douchebags who fly hang gliders to get some of these concepts without seeing a couple dozen people splattered on video.
Here I'll attempt to answer your questions regarding the Dragonfly's tow mast:
Here's a thought, Brad. Shut the fuck up and start listening to what Zack has to say about your goddam tow mast.
Zack C - 2013/03/05 18:45:16 UTC

Correct me if I'm wrong, but tug weak links are usually placed on the bridle above the tow ring (on the same side of it as the mast). Therefore, if the tug's weak link breaks and the bridle wraps on the tow ring, the tow mast weak link won't help. If the tug triggers the release and the bridle wraps, the tug's weak link will break before the mast. I don't see how the tow mast weak link provides protection from wraps.
Ok, the "wrap ups" I was referring to are those really rare ones where the weak link is somehow bypassed.
Oh, the weak link is SOMEHOW bypassed.

Here is the relevant REQUIREMENT for weak link installation from the 2009/03 version of the USHGA SOPs before the scumbags in the Towing Committee started gutting things to legalize the dangerous moronic practices you Dragonfly shitheads have institutionalized:
The United States Hang Gliding and Paragliding Association, Inc.
Standard Operating Procedure
12. Rating System
02. Pilot Proficiency System
10. Hang Gliding Aerotow Ratings
-B. Aero Vehicle Requirements

05. A weak link must be placed at both ends of the tow line.
So you tell me how it is physically possible for a 2009/03 legal front end weak link to be BYPASSED.
This is when the D-fly's break-away mast then steps up to become the new primary safety fuse.
- Yeah? Who's it keeping safe? If it's a safety fuse how come it scares me shitless?

- Oh! It's the new primary SAFETY FUSE! Now your towline tension is limited to FOUR HUNDRED POUNDS! And what could POSSIBLY happen to ANY Dragonfly with just four hundred pounds pulling back, up, down, left, right on it's extreme back end?

Lemme tell ya sumpin', asshole...

See this Dragonfly?

Image

It had a safety fuse between it and the solo glider almost twice as safe as the one Bobby Fucking-Genius Bailey built into the Dragonfly. So tell me how it got to be upside down on the runway with a bunch of state cops standing around it scribbling notes.
I've actually only seen this type of wrap-up happen once.
Oh. So it's a really rare event and you've only seen it happen once and the only way it can happen is if you violate the SOPs and flush common sense down the toilet but you've got to implement a fix which subjects me to being killed in EXACTLY the way Jeremiah Thompson and Arlan Birkett were EVERY TIME I FLY.
In my younger more risky days we used to do what I'd call 'extreme aerotowing'.
Oh. So you've gotten older and smarter and done things to decrease risk to YOU. Glad to hear it.
This is where the tug would do real aerobatics while the glider pilot tried to hold on.
Similar to the bullshit Chris Bulger pulled with a piece of shit release on his end just before tumbling and being ejected from his trike?
[and yes, the glider pilot had a "strong" weaklink during these wild events]
- A "strong" weak link meaning anything over 130 pounds Greenspot.
- Why? Did the glider want to make HIS OWN decisions about when to stay on and get off? My, what a quaint concept.
Anyway, after one such event the tug landed and somehow the tow bridle was wrapped around the mast and tied in a knot, with the weak link no longer in the load path.
A few more thoughts...

- Tow the glider in the SAFEST - rather than the MOST DANGEROUS - manner possible. (Note that people like Bill Bennett, Mike Del Signore, Rob Richardson, Mike Haas, Robin Strid, James Simpson, Steve Elliot, Roy Messing, Lois Preston, and Zack Marzec were all behind people trying to stay in position to optimize things for the glider but all wound up dead anyway.

- Put weak links on BOTH ends of the bridle (no, despite what you've heard from Quest and Florida Ridge, they don't double their strengths in this configuration) AND/OR one at the front end of the towline (just like it says (said) in the fucking manual).

- Since, apparently, the ONLY way to tie the bridle to the tow mast is to do stupid shit - to use the plane for useless bullshit for which it was not designed - maybe it's a good idea not to do stupid shit and instead use it to tow gliders up to workable thermal altitude.

- Lemme tell ya sumpin' - asshole...

Say you were using a 200 pound weak link to limit the towline tension to 400 pounds - which is all you can get with the breakaway. If the bridle ties itself in a knot to the tow mast half way up from the breakaway (top of the vertical stabilizer/rudder) your towline limitation is now 800 pounds. If the bridle ties itself to the tow mast a quarter way up your towline limitation is now 1600 pounds. Good freakin' luck.

- Totally awesome, dude, the way you matured from the days when you'd beef up weak links so you could do aerobatics with gliders in tow to the present point at which you're so safety conscious that you feel no obligation whatsoever to tow me, doing everything I possibly can to stay in position dead center behind you for my own benefit if not yours and armed to the teeth (literally) with releases I can blow in a nanosecond while maintaining maximum possible control of my glider through thermal conditions with anything heavier than a Marzec Link.
What makes the most sense to me...
Already I despise whatever's coming next.
...is letting the tug pilot decide what weak link strength he wants to use.
Yep... Nailed it.

Of course it does. You fly a tug.

But I fly a glider and what makes the most sense to me is selecting a weak link a small notch over the middle of the FAA safety/legal range (especially after seeing what happened to Zack flying at 1.0 Gs (flying weight) and having the fucking tug driver conform to the fucking FAA REGULATIONS - ASSHOLE.
I own my own tug and I do decide what weak link strength I use.
Regardless of whether or not it's a dangerous violation of FAA regulations and a configuration which has killed people because you know that you can do whatever the fuck you feel like and nothing will ever be enforced and you'll never be held accountable for anybody you kill.
Other tug pilots flying my tug are free to suggest other weak link strengths, but as the owner of the plane I reserve the right to agree or disagree.
And, of course, to piss all over FAA safety regulations - as discussed above.
Ultimately the decision comes down to who is responsible for the equipment.
Gee Brad, if I didn't know you fuckin' sociopaths as well as I do I'd thunk that you'd be more worried about being responsible for the safety of the guy who's paying you to getting him aloft than whether or not your tow mast breakaway gets bent.
No one is forcing the tug pilot to fly, and he has a right (and an obligation) not to fly if he feels the weak link is unsafe or inappropriate.
- Oh good, aviation based upon the FEELINGS of the halfwitted douchebags you typically find flying Dragonflies.

- Lemme tell ya sumpin', asshole... anybody on either end of the towline who takes off thinking that a weak link coming into play will be a safety factor in ANY flight has no fuckin' business taking off.

- Yeah Brad, no question whatsoever that the lighter the weak links at both ends of the towline the safer things are - FOR THE TUG. And it's also WAY safer - FOR THE TUG - if he loses the towline along with the glider.

- And that's OBVIOUSLY *ALL* you're concerned with.
It's also the tug pilot's responsibility to change the weaklink when necessary to avoid unacceptable weakening due to wear and tear.
- Unacceptable weakening which has some chance of killing the glider and a REAL GOOD chance of crashing it?
- Is it also the tug pilot's responsibility to comply with FAA aerotowing regulations?
The built-in weak link forces us to use a weak link to protect the weak link. As a result, we can't even increase glider pilot's weak link strengths to 200 lbs without being stronger than the tug's weak link.
As you are probably aware, there are sometimes offical protocols that are stated as "required" but are not always enforced.
- Name something that's EVER enforced in hang glider aerotowing. Every time somebody gets killed as a consequence of violating a USHGA regulation the only thing that happens is that the regulation gets deleted.

- We're not talkin' "official protocols" here - motherfucker. We're talkin' LAWS.
I am aware of multiple tug owner/operators who will tow anything that's willing to pay the tow bill, regardless of the tail-end configuration.
Name somebody who tows anything BUT deadly junk with kills contributing to its track record. If you spend years engineering something bulletproof and try showing it to Jim Keen-Intellect Rooney he just starts walking away without looking at it, declares it to be funky shit, and refuses to tow you.
Such tug pilots believe they can save themselves regardless of what does or doesn't happen on the ass-end of the line.
I only know of one who couldn't save himself.
- He had an underbuilt piece of shit release that couldn't handle any tension.
- He set the situation up by making an abrupt hotdog maneuver for no reason in smooth air.
- The tension probably never exceeded what Zack Marzec's Rooney Link allowed before it vaporized and killed him.
- He didn't bother to take the parachute he had in the trailer up with him.
- He wasn't using a restraint system capable of keeping him connected to the trike.

I only know of three tugs that crashed with gliders in tow that affected outcomes.
- Two of them were engine failures - the tug equivalents of a Rooney Link pops.
- Nobody's talking about the cause of the other one.
- All of them were pulling solos with Rooney Links.
- In none of them did a Rooney Link blow - meaning that if they'd been using 6.0 G weak links the outcomes would've been EXACTLY the same.
- At least two of them could've been mitigated by faster releases.
Buyer beware. Go ahead and pull out your MEGA-Link.
Nobody's talkin' MEGA-Link - you unbelievably stupid pigfucker. We're talking about weak links:
- the equivalent of what sailplanes use
- a half G south of what's legal
- ABOUT THE SAME AS YOU'RE USING NOW FOR TANDEMS
Who cares?
I'm guessing Zack Marzec was really caring as he was being blasted up to 150 feet and standing on his tail knowing just as well as his driver did what was just about to happen.
It's your butt on the line back there.
Goddam right it is. And *I* as the PILOT IN COMMAND of MY AIRCRAFT wanna be in as much control of what happens to it as possible. I don't want any decisions being made by a piece of fishing line some douchebag at the other end of the rope is mandating, I don't want MY LEGAL WEAK LINK being neutralized by the ILLEGAL WEAK LINK of some douchebag at the other end of the rope, and I don't want some douchebag at the other end of the rope making any fucking good decisions in the interest of MY SAFETY - seeing as how damn near all you douchebags at the other end of the rope have made it abundantly clear that you have nothing but the utmost contempt for me, my equipment, my competence as a pilot, and my personal safety.

You do your fuckin' job - LEGALLY - and let me do mine - WITHOUT INTERFERENCE.
Has there ever been a single instance of a tow mast break being desirable?
I actually don't personally know of one ever breaking.
- Yeah, you're forcing everybody up on illegally light weak links and crashing them and killing them for the sake of protecting your breakaway - big surprise. (I am SO HAPPY that the tow mast pulling half of Zack Marzec's tow tension came through that nasty freak accident unscathed and ready for more tows immediately after everybody got his story straight.)

- So what you're saying is that - even with tandems - there doesn't seem to be any record of one having a positive effect on the safety of ANY tow EVER.

- Thus NO MIDRANGE AND UP SOLO GLIDER can fly a midrange weak link without having it overriden by the tug's weak link and getting the rope because the tug's weak link is rated to protect the tug's tow mast breakaway which has NEVER ONCE IN THE FIELD been demonstrated to be of ANY USE.
During a wild rodeo ride behind a tug we once slightly deformed one, but it didn't break before the "strong" weak link did.
- Start talkin' POUNDS - motherfucker.

- So you were always in control enough to continue the tow, you weren't locking out, but the structure that's supposed to be up to the job of towing the glider WASN'T - RIGHT?
Similar to some other safety systems, it may never be needed.
But let's pack our parachutes, which, for all intents and purposes, are never needed by people other than assholes who blow aerobatics, so that they fall out of the containers and deploy about once every four flights 'cause... Who knows? We MIGHT be needing it sometime when it does and MIGHT not have been able to get to it fast enough.
I do feel better, though, knowing it's there.
- Oh good, more feelings from stupid pigfuckers.

- I feel much better knowing mine's THERE too. I feel better because I know it WON'T blow in any reasonable situation like Zack Marzec was in but WILL blow before my glider's overloaded. Why do YOU feel better knowing it's there?

- Mine's around 473 pounds? What's yours?

- What can you be sure yours can do for you that you're sure mine can't do for you.

- Asshole.
It's sort of like a fire protection sprinkler system or a parachute...
It's like a fire protection sprinkler system that goes off over the Thanksgiving dinner when you light a couple of candles or a parachute that falls out of the container when you're crossing the forest, salt marsh, canyon, lake, interstate, powerlines, lava field, or crocodile infested river.

Fire protection sprinkler systems have to be set so they DO NOT GO OFF unless there's something SERIOUSLY WRONG because if they do they can do tens of thousands of dollars worth of totally unnecessary damage in a matter of seconds.

There are NO PARACHUTES used for the safety of PILOTS that get deployed by anything other than DELIBERATE action by THE PILOTS.
...in that we hope we never need it...
WHAT DO *WE* *NEED* IT FOR?
Tost Flugzeuggerätebau

Weak links protect your aircraft against overloading.
*I'* have a RELEASE I can use to get off tow when *I* deem it appropriate. The fuckin' weak link is there ONLY to protect MY aircraft from being overloaded in a situation in which I've demonstrated. And that ain't never gonna happen. 'Cause if I can't even manage the tow to the extent that that's anything more than the remotest of possibilities there's NO WAY IN HELL I can handle the most critical part of the flight - the launch - where there's no possibility of ANY weak link doing me any GOOD and a HUGE probability that a Rooney Link is gonna crash me.
...but we know full well that we're safer WITH it in place...
YES. IN PLACE!!! UNTIL *NEEDED*!!! NOT GOING OFF AT RANDOM WHEN WE'VE GOT THINGS UNDER CONTROL AND KILLING US.
...and ready to kick-in when required.
And tell me how a two G weak link won't do that!
Apologies for the long post.
It's not the LENGTH. It's the EXASPERATING MIND BOGGLING *STUPIDITY*.

Summary...

You will happily use equipment on your end which has on a fair number of occasions killed people on our end and subject us to a considerable risk of being killed EVERY FLIGHT because you THINK it might give you a slight edge in some undefined bizarre scenario which in the ENTIRE HISTORY of hang glider aerotowing HAS NEVER ONCE HAPPENED.

Damn I hope they've got a very special place in hell reserved for you assholes.
Zack C
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Re: Weak links

Post by Zack C »

What makes the most sense to me is letting the tug pilot decide what weak link strength he wants to use.
Um...that was a quote from me. My meaning was that the strength of the weak link shouldn't be dictated by the aircraft (via the tow mast), but I could have made that clearer.
Tad Eareckson wrote:I only know of three tugs that crashed with gliders in tow that affected outcomes.
This is useful information. Can you give some names, links, or other identifying information on these cases? Were there other tug crashes with gliders in tow that didn't affect the outcomes?
Tad Eareckson wrote:I'm guessing Zack Marzec was really caring as he was being blasted up to 150 feet and standing on his tail knowing just as well as his driver did what was just about to happen.
One thing that's not clear to me about this event...when Zack hit the thermal, his angle of attack would have increased during the glider's initial upward acceleration. It seems like, if anything, this would cause the glider to want to nose down to keep flying at the angle of attack set by the bar position. So why would the glider be standing on its tail?

Zack
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Re: Weak links

Post by Warnarr »

Tad Eareckson wrote:I only know of three tugs that crashed with gliders in tow that affected outcomes.
This is useful information. Can you give some names, links, or other identifying information on these cases? Were there other tug crashes with gliders in tow that didn't affect the outcomes?
Ask Blindrodie to tell the bad karma episode of the Adventure Airsports tug being flipped on takeoff with a glider in tow.
I've got it saved somewhere but won't be able to locate it for a while.
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Tad Eareckson
Posts: 9161
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Re: Weak links

Post by Tad Eareckson »

Um...that was a quote from me...
Oops. Sorry 'bout that. Like I said, overwhelmed. Too much copying, pasting, formatting, editing...

No, you were OK. But if Brad had said it we all know what he'd have meant by it.
Can you give some names...
1992/05/17 - Dick Reynolds
http://www.kitestrings.org/post43.html#p43

2011/07/30 - Serious accident at SOGA
http://www.kitestrings.org/post613.html#p613
Spending the rest of his life in a wheelchair.

2012/11/03 - Frank Murphy
http://www.kitestrings.org/post3446.html#p3446

Also there was this one...

1984/00/00 - Dave Garrison
http://www.kitestrings.org/post2649.html#p2649
Slack line, tug wingtip snag. The weak link WAS to blame, however. Although it was within specs at takeoff it strengthened itself in the course of the emergency.
Subsequent testing of the weak links being used at the time showed that under certain conditions (e.g., with a gradually increasing load combined with the towline's elasticity) they could reach up to one and a half times their correct breaking load.
This was before Bobby Fucking-Genius Bailey discovered 130 pound Cortland Greenspot braided Dacron trolling line which meets our expectations of weakening itself in lockout situations and strengthening itself in turbulence. This crap did just the opposite.
Were there other tug crashes...
I don't know of any other tug crashes in which tugs were acting as tugs in the relevant timeframe but I one hundred percent guarantee you that if a driver died of a heart attack with a glider on a 1.2 G Tad-O-Link the glider pilot would be cut out of his harness and lynched and Yours Truly would have to spend the rest of his life in an undisclosed location.
One thing that's not clear to me about this event...
It may have wanted to nose down but it's still being pulled from forward with a thrust rapidly increasing from about 125 to 260 pounds - the tow tension doubles in the course of a couple of seconds.

This is a rerun of Dennis Pagen's pro tow adventure behind Neal Harris...
http://www.kitestrings.org/post17.html#p17
...'cept that luck motherfucker had HIS Rooney Link hold long enough to be able to fly out of it - just barely.

And don't anybody tell me that son of a bitch wasn't praying for his Rooney Link to hold just like the rest of us and didn't very deliberately exclude mention of it in his account - consistent with USHGA and Flight Park Mafia policies.
Ask Blindrodie to tell...
That can't POSSIBLY be true. Even if something like that WERE possible under the supervision of such a top notch Safety Director SURELY he'd have published an incident report for the benefit of all.
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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
Zack C - 2013/03/07 01:55:06 UTC
Davis Straub - 2013/03/06 21:48:38 UTC

I've already described them here.
I don't recall nor can I find that. Any help?
Brad Gryder - 2013/03/06 22:17:31 UTC

In my opinion, because we hang glider pilots are more exposed, have little crash protection, and can land almost anywhere in an emergency, then we would be better served to be near or below the lower end of the suggested weaklink strength spectrum.
Forgive me, but what do crash protection and landing options have to do with limiting tension? And what is the 'suggested weaklink strength spectrum'?
Any hang glider pilot who is fearful of having a weak link failure anytime during tow is in need of additional training.
During the times when weak link breaks are most dangerous, training will make little...
...or no...
...difference. I believe I've supported this so won't retread that ground.
I'd rather have my weak link serve a dual function (as both a safety fuse and as an emergency back-up release)...
Any weak link can serve as a backup release, including a stronger one. But expecting any weak link to do the job of a release can be fatal in a true emergency (i.e., near the ground). At altitude, the weak link strength won't matter.
Nothing scary happens on either end of the line, and both pilots fly away as normal.
Are you suggesting a pilot using a weak weak link cannot get into a scary situation forcing said weak link to break? What if the pilot in the following scenario had realized he was oscillating and thus decided to force the weak link to break on his second roll to the right? The outcome wouldn't have been much if any different.

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


As for what the tug feels, it's important to note that the tow force is a vector quantity consisting of both a magnitude and a direction. Weak links only limit the magnitude, but the direction is of greater concern to either aircraft. A glider with a 130 lb weak link is perfectly capable of endangering a tug. (If you doubt this, consider flying your tug with someone weighing 260 lbs (a force allowable by a 130 lb weak link) hanging from the back).
Brad Gryder - 2013/03/07 04:50:50 UTC
Zack C - 2013/03/07 01:55:06 UTC

Forgive me, but what do crash protection and landing options have to do with limiting tension?
Crash Protection - The minimal crash protection offered by a hang glider exposes the hg pilot to higher risk of serious injury or death associated with towline energy.
And they' ALSO have WAY slower takeoff/stall speeds. And energy goes up with the square of velocity. So don't forget to plug that into your bullshit equations.
The towline energy can be roughly said to be towline force times decel distance prior to weaklink rupture.
Hey. Here's a thought...

What if you got on the cart with a RELEASE you could ACTUALLY USE to abort the tow instead of being a total douchebag and getting on a cart with releases that can ONLY be used...

Image
http://ozreport.com/pub/images/fingerlakesaccident2.jpg
http://ozreport.com/pub/images/fingerlakesaccident3.jpg
Image

...when you DON'T really need to?
A sailplane pilot can afford to have a higher weaklink strength factor because the structure is absorbing the towline energy instead of just the hg pilot's helmet and bones.
And the damage limitation is just totally excellent with a Davis Link...

http://ozreport.com/13.003
Forbes, day one, task one
Davis Straub - 2009/01/03 20:50:24 UTC
Forbes Airport, New South Wales

Steve Elliot came off the cart crooked and things went from bad to worse as he augured in. He was helicoptered to Orange and eventually to Sydney where the prognosis is not good. I'll update as I find out more.
...around or off the bottom of the legal range that it would be totally foolish to think of going five or ten pounds higher.

Look - you off the scale stupid motherfucker...

- Whether you're using 130 or 1300 pound Greenspot when the glider's coming off the cart it's gonna be moving at EXACTLY the same speed as the tug - and that speed is plenty enough to kill you.

- What really fucks you up is when the glider comes to an abrupt stop and you keep going at the original speed until your head slams into the keel. (See photos above.)

- Whether the 130 or 1300 blows before or at the instant of the nose plant makes NO DIFFERENCE as to how fast your head's gonna hit the keel.

- And if the 1300 holds both you and the glider are gonna get dragged at 25 or 30 miles per hour for a while and that's not necessarily such a big fucking deal. People have done that and come out unscathed.

- Compare/Contrast with this total fucking asshole on a Davis Link:

http://groups.yahoo.com/group/skysailingtowing/message/6726
Weaklinks
Peter Birren - 2008/10/27 23:41:49 UTC

I know about this type of accident because it happened to me, breaking four ribs and my larynx... and I was aerotowing using a dolly. The shit happened so fast there was no room for thought much less action. But I wasn't dragged because the weaklink did its job and broke immediately on impact.
who's too fucking stupid to be able to both grasp the concept of a release that can be used to abort a tow in an emergency and stay on the goddam cart until he's up to flying speed.

Furthermore...

There is ZERO excuse for getting on a cart with a release you can't blow BEFORE hitting the ground and/or blowing a dolly launch and I don't really give a rat's ass what happens to these bozos. I'm only interested in protecting PILOTS. And THE SINGLE BIGGEST THREAT to PILOTS is a Davis Link, it's about the ONLY thing that crashes them on takeoff, and it's damn near the only thing that can kill them that they have no control over.
Landing Options - Because landing out, turning-back-to-field, number of safe landing spots within glide, etc. are quite different between the hg and the sailplane, the sailplane pilot can justify using a higher weaklink strength factor than his hg counterpart.
From both influences considered here (crash protection & landing options), the sailplane pilot's optimum weaklink strength is a higher percentage of his total weight than the hang glider pilot's optimum would be.
Gee, and after three decades worth of hearing totally moronic and insane comments about hang gliding weak links and thinking nobody could come up with anything new that far off the scale.

"MY GOD!!! HE'S TOWING ME OVER THE FOREST!!! AND THERE ARE *WOLVES* IN THAT FOREST!!!

If ONLY I had listened to Brad, Bobby, Paul, Lauren, Davis, and Rooney and used a standard aerotow weak link it would've blown by now and I'd have been able to glide back to the airport!

But now I'm stuck behind the Dragonfly until it runs out of gas. Then we're going down where we'll both be torn to shreds within the first two minutes."
In fucking credible. This is what you get in a state in which it's legal for brothers and sisters to marry for more than three consecutive generations.
>
Edit - 2013/03/08
Misread what he was saying. Still stupid but nowhere near as. Must redo when I get the time.
<
And what is the 'suggested weaklink strength spectrum'?
I think someone on one of the threads was referring to the FAA's range being between 80% to 200% of the maximum gross weight, so that's the spectrum I'm referencing.
Yeah. Did you notice that it applies to hang gliders too?
During the times when weak link breaks are most dangerous, training will make little difference. I believe I've supported this so won't retread that ground.
But if the weak link breaks sooner verses later, the pilot is hopefully in a better position...
Yeah, that's always our hope and expectation. No matter how many tons of data we have indicating that that's total bullshit and the actual case is the precise opposite. Little girls do just fine with the same weak links that are crashing big dudes left and right.
...with less energy stored in his wing...
That's a bit odd. I had been under the impression that having energy in a wing was a good thing.

- It seems whenever I leave BWI that the guys in the cockpit are really winding up those engines as they start rolling down the runway.

- And:

-- I think I remember something from my first lessons on the dunes that I was supposed to hold the nose down, run like hell, and get the wing into the air with as much energy as possible.

-- in flying through turbulence I was supposed to maintain extra energy to avoid getting tossed around and stalled

-- when I came in to land I was supposed to come in hot to be able to punch through rotors and gradient

There's just so much about aerotowing that seems to be the total opposite of everything else I've learned.
...and barrel...
Oh yeah... That I can see. DEFINITELY don't wanna be transmitting much energy through one of those Bobby Fucking-Genius Bailey...

http://www.hanggliding.org/viewtopic.php?t=21033
barrels release without any tension except weight of rope..
Bart Weghorst - 2011/02/25 19:06:26 UTC

I've had it once where the pin had bent inside the barrel from excessive tow force. My weaklink was still intact. The tug pilot's weaklink broke so I had the rope. I had to use two hands to get the pin out of the barrel.

No stress because I was high.
...barrels. Or, for that matter, one of Matt's new and improved two point...

http://www.hanggliding.org/viewtopic.php?t=22540
LMFP release dysfunction
Diev Hart - 2011/07/14 17:19:12 UTC

I have had issues with them releasing under load. So I don't try to release it under a lot of load now.
...barrels.
...so that both have a higher probability of performing their intended design functions without being forced way beyond their normal ranges.
The INTENDED DESIGN FUNCTION of the:

- wing is to handle 55 miles per hour of airspeed and six Gs of load force - ASSHOLE. We NEVER get anywhere NEAR the edges of any design envelopes in hang glider towing.

- Industry Standard barrel release is to sell barrel releases - NOTHING MORE. It was not DESIGNED to do the job...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3391
More on Zapata and weak link
Paul Tjaden - 2008/07/22 04:32:22 UTC

I have never had a lockout situation happen so quickly and dramatically and had no chance to release as I have always thought I could do.
...people are trying to use it for. Just like the fucking Bobby Link. They're trying to use Bobby Links, which don't work, to do the job of Bobby Releases, which don't work. The result is an ENORMOUS number of crashes and a fair number of fatalities.
Are you suggesting a pilot using a weak weak link cannot get into a scary situation forcing said weak link to break?
No. But I will state that it's much more difficult for any pilot to get himself into a scary situation by breaking a "weak" weak link on-the-fly than it is if the weak link is stronger.
Sure, just ask Davis and the despicable shits running Quest trying to get this written off as a freak accident in which the Davis Link had absolutely no bearing.
What if the pilot in the following scenario had realized he was oscillating and thus decided to force the weak link to break on his second roll to the right?
First, I'd like to say that this pilot did a very poor job during that flight.
http://www.youtube.com/watch?v=F_n5B3-MIC4


No shit.
I hope you agree.
No, I really didn't see anything wrong.
He climbs way too high, way too early. So now he's sittin' up there waiting for the dang trike to come up, almost stalled, and losing tension.
What's this? All the sudden losing tension is a BAD thing?

I always thought that high line tensions reduce the pilot's ability to control the glider...
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.
...and we all know that the killer "lockout" is caused by high towline tension.
A wing drops and he recovers, but he's still barely flying. He then oscillates and tip stalls.
1) Why did he outclimb the trike so much? Insufficient training? He should have either released or been given the rope.
2) Why does he not reduce his pitch and come down to the tug so they can both get on with their flying instead of all this mushing around?
Thank you for pointing out that this guy had no clue what he was doing.
3) To answer your question, it's just dumb and potentially suicidal to force a weak link to break when you're that low and that out-of-whack...
I TOTALLY disagree...

http://www.hanggliding.org/viewtopic.php?t=14230
pro tow set-up
Jim Rooney - 2009/11/03 06:16:56 UTC

As for being in a situation where you can't or don't want to let go, Ryan's got the right idea. They're called "weak" links for a reason. Overload that puppy and you bet your ass it's going to break.

You can tell me till you're blue in the face about situations where it theoretically won't let go or you can drone on and on about how "weaklinks only protect the glider" (which is BS btw)... and I can tell ya... I could give a crap, cuz just pitch out abruptly and that little piece of string doesn't have a chance in hell. Take your theory and shove it... I'm saving my a$$.
Take your theory and shove it... I'm saving my a$$.
...but weaker would be better than strong.
OK. If you're gonna send somebody up who has no fucking clue what he's doing make sure he's on a weak link light enough to blow at random. That should make things OK - it'll probably break before he can get into too much trouble.
A glider with a 130 lb weak link is perfectly capable of endangering a tug. (If you doubt this, consider flying your tug with someone weighing 260 lbs (a force allowable by a 130 lb weak link) hanging from the back).
I disagree.
Oh good. Now I know which position to take.
Such a glider isn't "perfectly" capable of endangering a tug.
No. Just "imperfectly".
Actually, if the tug pilot is well experienced and his Dragonfly is properly maintained then there is more chance of him getting killed by a meteor.
Fine. Rooney Link, meteor - as long as he's killed I'm pretty happy.
He's never going to let that glider get that far out of whack before he takes matters into his own hands.
Which, of course, he'd be totally unable to do were the glider on a six hundred pound weak link.
First he'll maneuver to "aid and assist" the glider, then he'll adjust the mirror and maybe make a hand signal or two, then once he realizes he's being played with he'll lighten up and just see what the new kid is willing to take back there.
Which, of course, he'd be totally unable to do were the glider on a six hundred pound weak link.
You see, if the glider is still flying back there then it can't get but so far out of alignment with the tug's longitudinal axis.
Unless, of course, he's using a one and a half G weak link - then all bets are off.
It's not like it can become a plumb bob hanging from the stinger.
So then why the fuck are you so goddam phobic about having a solo glider on a 1.5 G weak link and keeping the one on your end up to legal snuff?

Pick one, dude. Either the Rooney Link is vitally important as the focal point of a safe towing system for preventing the glider from getting too far out of whack or a glider getting too far out of whack is something that doesn't happen / is easily dealt with / isn't a problem.
So go ahead, make my day. Let's meet up somewhere and you can try to kill me with your glider and whatever MEGA-link fits in your holster.
No way in hell I'd get behind an asshole like you for ANY reason. We've got regulations, they need to be enforced, and we've gotta start requiring tug drivers to have grade school diplomas and at least double digit IQs.
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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
William Olive - 2013/03/07 05:03:10 UTC

I'm pretty much on the page with you with all your arguments...
Yeah, big surprise.
...but I have to disagree over this one.
We'll take all the disagreement we can get.
A HG pilot with a single loop of Greenspot (or brickie's twine or mason's string) is quite capable of picking up the back of a tug to the point where it will endanger the tug. The tug driver has options of course, but the weaklink isn't one of them. This is just another job that we shouldn't be assigning to the weaklink.
Oh, let's not start taking imaginary benefits of Rooney Links off the table. That'll start seriously cutting into the Rooney Link's ability to increase the safety of the towing operation - PERIOD.
Jim Rooney - 2013/03/07 06:40:02 UTC
Brad Gryder - 2013/03/07 04:50:50 UTC

I disagree. Such a glider isn't "perfectly" capable of endangering a tug.
From first hand experience, I'm sorry to say that you're quite wrong.
They are rather capable and some have tried to kill me.
But it's OK to fly with a Rooney Link capable of killing you. It's just not OK to fly with a Tad-O-Link capable of killing you.
Yes, I have, and have used, the option of letting them go.
No shit. So if a glider is starting to get to the point at which it's causing you a problem you use your RELEASE to RELEASE the glider. That's a pretty strange concept for a back ender whose only option is to wait for his Rooney Link to blow - and hope that it happens soon enough to do me any good.
As Davis said here or somewhere else... I have no idea where this "purpose of the weaklink" nonsense got started, but it's utter nonsense ok. Stop it.
http://ozreport.com/forum/viewtopic.php?t=24534
It's a wrap
Davis Straub - 2011/07/31 17:55:25 UTC

To break under load before the glider does.
The "purpose" of a weaklink is to improve the safety of the system.
PERIOD
Now where have I heard something like that before? Oh yeah...

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Jim Rooney - 2011/08/26 02:44:10 UTC

The "purpose" of a weaklink is to increase the safety of the towing operation. PERIOD.
And we still have NO IDEA what the problem with Zack Marzec's last flight was.
It's not "lockout protection"... but I'll be damned if it hasn't stopped some of the muppets I've had to tow from locking out.
- Muppets... So how many derogatory terms DO you have for people trying to aerotow hang gliders?

- So you're towing muppets who are both unable to safely control the glider on tow and abort when they get dangerously out of control and trusting their lives to a piece of fishing line that...
Jim Rooney - 2011/08/26 02:44:10 UTC

Now, how it does this also provides a telling answer to one of the most hot button topics surrounding weak links... lockouts.
People will rail up and down that weaklinks do not protect against lockouts... which they don't.
But this is a half truth.

The whole truth is that while they don't prevent them, they help.
...doesn't PREVENT lockouts but "HELPS".

Good thing it helps your muppets better than it helped Roy Messing and Lois Preston.
Is that what's it's "for"?
Tost Flugzeuggerätebau

Weak links protect your aircraft against overloading.
Who cares what it's "for"?
People who understand towing theory. Pilots.
Who cares what it's "purpose" is?... or more specifically, what *you* define it as?
I make the calls on how to control my glider through a safe tow or safely abort if the situation demands and my weak link makes the call on when to keep by glider from being overloaded. And If I ever let things get to that point I better be REALLY HIGH 'cause otherwise I might not be around very much longer to enjoy the benefit of having my weak link do its job.
It helps.
And NEVER EVER hurts. Just inconveniences six out of six times.
Is it perfect?
For doing it's job of preventing overload? ABSOLUTELY.
No, of course not.
For doing what YOU want it do? It totally sucks. And with the rating you're mandating to try to get it to do jobs it can't we're a thousand times better off than not having a weak link AT ALL.
Does it "prevent" lockouts... of course not.
Should you rely on it to do so? Nope.
Talked to Malcolm lately?
Does it help you when you're f*cking up?
You better believe it.
Yep... Get your nose a little high...

http://groups.yahoo.com/group/TTTFlymail/message/11545
Cart stuck incidents
Keith Skiles - 2011/06/02 19:50:13 UTC

I witnessed the one at Lookout. It was pretty ugly. Low angle of attack, too much speed and flew off the cart like a rocket until the weak link broke, she stalled and it turned back towards the ground.
http://www.youtube.com/watch?v=VYe3YmdIQTM


Sorts you right out. Teaches you a lesson you won't soon forget. Although I don't no how much good that did these two individuals 'cause they never returned to the sport.
Does it do other things?
You bet it does.
No argument...

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

...there.
So... if it's *only* purpose is to prevent your glider from breaking apart... which is complete and utter bullshit... but if that was it's only purpose... why then do we have them at all?
Your glider will tear the rope apart before it breaks.
It will tear the towmast off the tug before it breaks.
Your glider is capable of amazing feats of strength... it is in no danger of folding up on you.
Really? That's not what I remember hearing...
Jim Rooney - 2011/08/26 02:44:10 UTC

See, in truck towing, a weaklink does next to nothing for you (unless the line snags).
This is because you're on a pressure regulated system... so the forces never get high enough to break the link.

This is not the case with an aerotow.
This is why the weaklink exists.

The forces of an aerotow can get high enough to tear the wings off the glider.
This is no exaggeration... it can be done.
...from probably the most highly respected authority in the sport.
So why have a weaklink at all?
The answer?
Because... brace yourself... You're wrong.
I know, it sounds crazy, but it's actually true.
The *purpose* of a weaklink... is... well... perhaps a bit more than just one simple little thing.
Yeah, it would probably take me hours to list all of the little things people have expectations of Rooney Links doing. And I can sum up their downsides in one word:

http://www.youtube.com/watch?v=eTKIAvqd7GI


INCONVENIENCE.
Is the *purpose* of my tow release "lockout prevention"?
No.
Well, obviously not any of...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3107
I have a tandem rating!!!
Lauren Tjaden - 2008/03/23 22:20:15 UTC

When Jim got me locked out to the right, I couldn't keep the pitch of the glider with one hand for more than a second (the pressure was a zillion pounds, more or less), but the F'ing release slid around when I tried to hit it. The barrel release wouldn't work because we had too much pressure on it.

Anyhow, the tandem can indeed perform big wingovers, as I demonstrated when I finally got separated from the tug.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3391
More on Zapata and weak link
Paul Tjaden - 2008/07/22 04:32:22 UTC

I have never had a lockout situation happen so quickly and dramatically and had no chance to release as I have always thought I could do.
...YOUR tow releases.
But I'll be damned...
You apparently haven't figured this out yet, but you're damned anyway - and there ain't shit you can do about it at this point.
...if I won't use it to do so.
Well...

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.
Try anyway.
See... same thing.
Yeah. Exactly. No reliable way to either stay on tow when your life depends on it or get off tow when your life depends on it.

So keep rolling those dice - motherfucker.
Zack C
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Re: Weak links

Post by Zack C »

Tad Eareckson wrote:It may have wanted to nose down but it's still being pulled from forward with a thrust rapidly increasing from about 125 to 260 pounds - the tow tension doubles in the course of a couple of seconds.
Then how can you be so sure a stronger weak link would have held? At what point would tension start decreasing again?

Zack
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Tad Eareckson
Posts: 9161
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Re: Weak links

Post by Tad Eareckson »

Then how can you be so sure a stronger weak link would have held?
It's not gonna KEEP increasing at a rate like that (unless there's a black hole or sumpin' nearby). It's just a FREAKIN' GUST - the kind of thing we get bounced around by on tow at altitude - where the thermals have had some time and distance to build up some momentum - all the time. Hell, we fly into dust devils at altitude without much problem.
At what point would tension start decreasing again?
About a tenth of a second after his Rooney Link clearly provided him protection from his excessive angle of attack for that form of towing.
This WAS NOT anything all that...

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.
...extraordinary. Mark doesn't cite it as even THE strongest thermal activity he's felt LEAVING THE FIELD - and apparently nobody else got killed on virtually identical occasions. (Hell, he doesn't even cite losing gliders on any of those occasions).
Mark Frutiger - 2013/02/08 19:12:21 UTC

Zack hit the lift a few seconds after I did.
Let's call the airspeed 30 miles per hour (probably a bit faster but let's make the math easy and bias things in their freak accident favor) - 44 feet per second. 250 foot towline. Zack hits the thermal less than six seconds after Mark. Mark's stabilized in the goddam thermal in about two seconds. Minus the fuckin' Rooney Link Zack would've been too.

Put Zack on a 400 pound Tad-O-Link. That's 140 over what he had. Normal 914 tow tension I'm calling 125. So he gets an extra Dragonfly's worth plus change.

And the longer and harder he pulls on that string the more he slows down the tug.

Now go back and finish killing Rooney, Rodie, Brad, and Davis.
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Tad Eareckson
Posts: 9161
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Re: Weak links

Post by Tad Eareckson »

Hey Jim...

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

You've not heard about strong-link incidents.
Uh, yeah... cuz we don't let you use them.

"light" weaklink issues?
"I had to land"... boo hoo.
Oh, I thought of an other one... I smashed into the earth after my weaklink let go cuz I fly as badly as I tow, and I'm only still here cuz my weaklink didn't let me pile in harder.

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.
http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Rooney - 2013/02/11 19:22:18 UTC

Sorry, I'm sick and tired of all these soap box bullshit assheads that feel the need to spout their shit at funerals. I just buried my friend and you're seizing the moment to preach your bullshit? GO FUCK YOURSELF!!!!!!!!

I can barely stand these pompus asswipes on a normal day.
http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Jim Rooney - 2013/03/07 06:40:02 UTC

As Davis said here or somewhere else... I have no idea where this "purpose of the weaklink" nonsense got started, but it's utter nonsense ok. Stop it.

The "purpose" of a weaklink is to improve the safety of the system.
PERIOD

It's not "lockout protection"... but I'll be damned if it hasn't stopped some of the muppets I've had to tow from locking out.
Was your friend a muppet or a rock star?

Is it better to be a live muppet or a dead rock star?

How 'bout a live soap box bullshit asshead or pompus asswipe versus a dead rock star?

Is there any possibility whatsoever that a live muppet, soap box bullshit asshead, or pompus asswipe could understand something about aerotowing that a dead rock star somehow managed to miss in his rise to the top?
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Tad Eareckson
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Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Freedomspyder - 2013/03/07 02:06:31 UTC

I would expect a stronger weaklink to allow a wider "operational envelope" not narrower. But wider only on the higher tension side of the equation.

You seem to be suggesting the weaker weaklink gives you a wider "operational envelope"; 1) because you can break it at will, 2) because it will break earlier preventing and/or reducing the worst kinds of stalls and lockouts, 3)..4)..5)...

Why not just use your release?
Because, Industry Standard equipment...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3391
More on Zapata and weak link
Paul Tjaden - 2008/07/22 04:32:22 UTC

I have never had a lockout situation happen so quickly and dramatically and had no chance to release as I have always thought I could do.
...never seems to work as well as people always think it will.
I've been avoiding the release in this discussion...
Not nearly as effectively as the Quest aligned forces have been avoiding discussing Rooney Links.
...but shouldn't it allow control over the acceptable "operational envelope" anywhere within it. Icy conditions nonetheless.
Talk to Deltaman.
Jim Rooney - 2013/03/07 06:47:22 UTC

That's exactly the problem.
People get themselves in the shit on the high tension side... a stronger weaklink gives you more tension... allows for stronger whipstalls/etc.
Well I'm baffled by this.

- Zack Marzec was a professional Kitty Hawk glider pilot towing behind a professional Quest tug pilot.

- He was five pounds under the PERFECT weight for the PERFECT weak link - the Quest 130 or 260 or 360 or 520 or whatever they're calling it this week.

Yet he got himself into this shit and his Quest Link allowed for a moderately strong whipstall, et cetera...
People that are in the shit are asking for stronger gear to get further into the shit?
And after...
Jim Rooney - 2013/02/12 18:00:27 UTC

I get tired as hell "refuting" all these mouth release and "strong link" arguments.
...you've tired yourself so heroically "refuting" all these mouth release and "strong link" arguments?
I'm baffled.
Whoa! You're baffled TOO! You and me both, bro.
Freedomspyder - 2013/03/07 14:17:12 UTC

Would you advocate even weaker than 130lbs?
- Of course not. You can't advocate weak links under 130 to limit the severity of whipstalls because that's not an accepted practice. Who knows? It might actually INCREASE the severity of whipstalls? And how are ya gonna find out anyway? Jim has a general rule of "no funky shit" and...
Jim Rooney - 2013/02/16 05:05:41 UTC

My general rule is "no funky shit". I don't like people reinventing the wheel and I don't like test pilots.
...he doesn't like people reinventing the wheel and he doesn't like test pilots.

- You'd think. I mean, it was the Industry Standard for decades.
Quest Air - Aerotow FAQ

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.
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 pound braided Dacron line, so that one loop (which is the equivalent to two strands) is about 260 pounds strong - about the average wing load of a single pilot on a typical glider.

Maybe five or ten pounds lighter for gliders under the average, just five pounds over perfect for Zack Marzec, maybe five or ten pounds lighter for gliders over the average.
Or based upon experience? Based on weight of the pilot? Weather conditions? Or what...?
I'd go with "what". That's pretty close to...

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

The accepted standards and practices changed.
...the accepted standards and practices changed.
In your opinion, are these guys using the 200lb string pushing the "whipstalls/etc" envelope?
Hell no! It's an accepted standard and practice now. And if a commercial interest is doing something there COULDN'T POSSIBLY be anything wrong with it. It was only an insanely dangerous practice...

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

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.
...BEFORE a commercial interest started doing it.
For example, your pal? I know you mentioned he was quite light.
Yeah. MAJOR strategic error.
Do you think he should have came off of the tow earlier? Either with a release or weaklink?
No, he was a friend of Rooney's - so OBVIOUSLY he was doing everything - from equipment selection to in flight decisions and actions - PERFECTLY. And if he had been using 200 instead of 130 that would've been PERFECT TOO. But he'd have still been killed just as dead because there's no proven link between the weak link strength and the fatal whipstall.
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