Weak links

General discussion about the sport of hang gliding
Zack C
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Re: Weak links

Post by Zack C »

Dang Tad, that was (aptly) scathing. Wish I'd waited to respond to him. =)

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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

Don't worry. He'll provide you plenty more opportunities.
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Re: Weak links

Post by Zack C »

I'm doubtful.
ksykes wrote:Zack - I choose not to get on the Tad part 2 merry-go-round. But please enjoy yourself.
http://www.hanggliding.org/viewtopic.php?p=292122#292122

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Re: Weak links

Post by Zack C »

What did I tell you. =)
Ksykes wrote:But I am falling into the feeding the troll trap. Enjoy talking to yourself. Thanks Scare for the ignore button.
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Re: Weak links

Post by Tad Eareckson »

It's amazing just how much breathing he's capable of with his head that deep in the sand and/or far up his ass so much of the time.

We did a little damage on this one - nothing near as much as I had hoped but a fair bit more than I expected. People - including even Kinsley - are shaken up by the idea that they can be doing everything that much by the USHGA / Pagen / Davis / Flight Park Mafia book on the kind of day that everyone shoots for and end up that dead that quick without a lockout being involved.

The bad guys are all SO painted into corners. There's NOTHING they can say without blatantly contradicting five or ten previous statements we have on record. Rooney, Davis, Trisa, Bobby, Russell, Mitch, Paul, Lauren, Malcolm are all TOAST.

And it'll be fun watching how USHGA tries to deal with it. If they:
- report it honestly it reveals the Trisa article as the crap that it is
- lie that'll be obvious to everyone 'cause there are too many solid and corroborated statements floating around
- don't report on something this major that'll be conspicuous by its absence

No sweeping it under the rug and getting away with it like they did with Terry.

It's gonna take me a month to finish chewing up the crap that's up there now. Keep on any heat you can manage.
---
2022/09/14 17:00:00 UTC

There WAS a lockout involved - a straight up vertical one that couldn't be arrested as a consequence of Zack being too skilled to need to be flying with a two point bridle. But fortunately he was flying with a Standard Aerotow Weak Link that worked before he got into too much trouble. (Half a year shy of a decade now.)
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=28290
Report about fatal accident at Quest Air Hang Gliding
Davis Straub - 2013/02/09 20:29:52 UTC

180 lb pilot, 75 pound glider, 38" tow bridle, chest loops 12" apart, pro tow set up.
Each line of the bridle would be carrying 135 pounds at 1 G force.
A loop of 130 lb Cortland Greenspot breaks at about, well see here:
http://ozreport.com/9.049#1
180 lb pilot
How 'bout the parachute, harness, helmet...
75 pound glider
How 'bout the max certified operating weight - which, for the purposes of weak links and their legality, is all we have to know?
38" tow bridle
What about the length of the piece of crap bent pin Bailey Release assembly on his right shoulder?
chest loops 12" apart
That's awfully generous - especially when things are loaded up and the straps are squeezed together.
pro tow set up
Yeah, we know. The guy was a REAL PRO operating at a REAL PRO operation - so he didn't need no stinking two point setup to help him keep/pull the nose down.
Each line of the bridle would be carrying 135 pounds at 1 G force.
If the 180 pound pilot weight is actually the hook-in weight at we're talking 128 pounds plus a little. So fine, call it 135 pounds.

Let's make the glider a 137 - which is what Casey seems to think it was - to give everybody the benefit of the doubt. Max certified operating weight: 308 pounds.

A one G weak link on a bridle end is is something a little over 154 pounds. Minimum allowable: 123 plus pounds. Fresh 130 Greenspot on the test rig can blow at that - in the air after the cart's been accelerated it can blow at under two thirds of that.

At the two G top end the weak link is feeling over the 308 pounds. And it would've been a REAL GOOD idea for Zack to have had a three hundred pounder - even if that was nearly twice what his piece of shit Bailey Release...

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

But 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 2 hands to get the pin out of the barrel.
http://www.flickr.com/photos/aerotowrelease/8331326948/
Image
No stress because I was high.
...could handle.
A loop of 130 lb Cortland Greenspot breaks at about, well see here...
Yeah, let's go there, Davis.

http://ozreport.com/9.049
Weaklinks
Davis Straub - 2005/03/01

The standard in the US is 130 lb test line in one loop with a fisherman's knot.
The standard in the US then and now, motherfucker, is the same as it is for sailplanes - eighty to two hundred percent max certified operating weight. And that's ACTUAL - not what some stupid Flight Park Mafia shit says it is.
We were thinking and talking about weaklinks the other day here at Quest Air, given all the discussion about them on the Tow Group on the Oz Report forum and in the Oz Report since the Worlds.
At which you fucking douchebags accommodated Robin's successful effort to kill himself with a piece of shit release configuration.
Steve Kroop, Bob Lane, and Rhett Radford decided to do a few quick and dirty tests just to see if a looped 130 lbs test line (IGFA DACRON TROLLING LINE) would hold 260 pounds with or without tying the loop so that the knot was "hidden."
You mean like a decade and a half after all you fucking douchebags had been telling everyone it would and forcing them to fly it when it was going off like popcorn with gliders straight, level and smooth?
We looped one end of a weaklink loop to the loop of a spectra bridle (part of a pro-tow and available here at Quest Air) and the other end to a loop of webbing approximately as thick as the loops that you would find on the shoulders of your harness.
Yeah, why would you put it on a bridle end where it engages the piece of shit Bailey Release whose protection it so desperately needs?
Tying the spectra to the hang gliding real life simulator outside the Quest Air and Flytec office entrance, Steve Kroop, and then Rhett Radford, slowly raised themselves up from a seated position by slowly pulling on the loop.
Did the use latex gloves and breathing masks to ensure real accurate results?
The weaklink broke before they were able to get their weigh off the ground. Steve and Rhett are quite a bit less than 200 pounds.
What a load of crap.
The weaklink broke whether the knot was hidden or not.
No it didn't. You obviously didn't read Dr. Trisa Tilletti's article in the June issue of Hang Gliding.
Therefore I assume that the single loop of 130 lbs test line is providing a weaklink strength of about 1/2 G, about 120-150 pounds.
Yeah, and let's throw heavier gliders - like me - out of the equation.
Rhett remembers earlier tests which showed the strength of 135 lbs braided fishing line at 180-200 lbs.
Well let's use those numbers then - since it will give the Flight Park Mafia even more justification for putting people up on the crap that killed Zack last weekend.
There is one additional strand on the end of the v-bridle at the Dragonfly side.
Yeah?
- Why?
- What did that configuration test to?
I assume that we don't want to have a stronger weaklink at the pilot side relative to the Dragonfly side.
Try this, douchebag... Put a weak link in the middle of the legal range on the glider and put something heavier on the goddam tug.
Still, given these results I think I'll test two loops and see if it can hold my weight. I assume that 1 G or so breaking would be enough to provide a reasonable margin of safety in the event that I came off the cart and plowed in.
For starters, why don't you do twenty or thirty test crashes at three quarters of a G and get back to us on the worst you got hurt - asshole.
I wonder just how strong the brick layer's line in Australia is supposed to be. They use four strands (to six strand for heavy pilots) in Australia of this line. I had always assumed that it was weaker than the line used in the US, just because they used more of it. Four stands were supposed to be at least 190 pounds, so it does seem to be weaker.
What a load of crap.
Follow up:

Steve Kroop, Rhett Radford and I went out again and tested four strands of this line. Steve was able to lift his 185 lbs off the ground, and when I added a very small bit of tugging (slowly) on the line, it broke. Say 200 pounds. Four strands, still less than 1 G (300 pounds).
Try something like THIS:

http://www.flickr.com/photos/aerotowrelease/8317889807/
Image

so we can talk about actual numbers for something new and different.
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. It is a de facto standard, because it works for most pilots and gliders and is usually near the USHPA recommendation of a nominal 1G weak link for most pilots.
Therefore I assume that the single loop of 130 lbs test line...
I assume that we don't want to have a stronger weaklink...
I assume that 1 G or so breaking would be enough...
I had always assumed that it was weaker...
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=28290
Report about fatal accident at Quest Air Hang Gliding
Davis Straub - 2013/02/09 17:05:30 UTC

Just to point out, on a protow bridle the forces are divided in half.
Well yeah, Mister Pro Toad. HOWEVER... If you put Davis Links on BOTH ends of the bridle...

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

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.
...you can ignore that issue.

http://ozreport.com/forum/viewtopic.php?t=24534
It's a wrap
Davis Straub - 2011/07/30 19:51:54 UTC

I'm very happy with the way Quest Air (Bobby Bailey designed) does it now.
I'm really surprised you didn't point that out.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Kinsley Sykes - 2011/08/31 11:35:36 UTC

Well actually he didn't. But if you don't want to listen to the folks that actually know what they are talking about, go ahead.
Feel free to go the the tow park that Tad runs...
We're really counting on people like you to spread the word on the way Quest Air (Bobby Bailey designed) does things. And when you start dropping the ball promoting the folks who actually know what they are talking about then people are gonna start feeling free to go to the tow park that Tad runs.
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Re: Weak links

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=28290
Report about fatal accident at Quest Air Hang Gliding
Zack C - 2013/02/09 16:57:11 UTC
If you had been properly trained on how to tow, you would know that it shouldn't be a big deal when a weak link breaks, even just after coming off the cart, if you are doing things right.
Paul, are you saying Zack M wasn't properly trained on how to tow?
If he says yes just think of what that implies about everyone who's ever come out of Kitty Hawk's aerotow program at Currituck.
one strand is 130 lb, two strands, (one loop), is more.
Tad Eareckson - 2013/02/09 20:13:38 UTC

tiger12, by the way, is Mark Frutiger - the Dragonfly driver whose incompetence and negligence in towing Zack one point into and through a monster thermal on a Quest Link at or below the legal limit were big factors in the fatal crash.
You would think, but two stands will break around 130 lbs, at least when attached to a Spectra bridle. This has been experimentally verified many times by many people.
Well yeah, but...
Dr. Trisa Tilletti - 2012/06

We could get into details of lab testing weak links and bridles, but this article is already getting long. That would be a good topic for an article in the future. Besides, with our backgrounds in formal research, you and I both know that lab tests may produce results with good internal validity, but are often weak in regard to external validity--meaning lab conditions cannot completely include all the factors and variability that exists in the big, real world.
...as you and I both know, lab tests may produce results with good internal validity, but are often weak in regard to external validity - meaning lab conditions cannot completely include all the factors and variability that exists in the big, real world.

If you REALLY wanna find out how little it takes to blow these things you should pro tow a pro through a big, real world monster thermal at a hundred and fifty feet and see what happens.
The Aerotow weaklink is designed to break before a glider can lockout in roll.
Weak links cannot do this. The best they can do is break when a certain tension is reached, and lockouts are not a function of tension. See:

http://www.hanggliding.org/viewtopic.php?p=291768#291768
weak links
http://www.youtube.com/watch?v=F_n5B3-MIC4


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

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...
When the Rooney Link blows, Mark, be it due to a pitch-up or a lockout, the load on the tug is EXACTLY THE SAME. The ALIGNMENT and EFFECT ON CONTROL, however, tends to be quite a bit different.

And even a Rooney Link can provide enough misalignment and compromise of control to kill a Dragonfly in the wrong combination of circumstances.

That's why whenever a tug driver starts talking about the effect of weak link strength on his safety margins you know you're listening to a total moron - lest there have been any doubt in the first place.
Paul Hurless - 2013/02/09 08:49:22 UTC

No, I was replying to Micheal170 after he posted his usual parroting of his sociopathic role model, Tad.
Did you ever stop to consider for a moment that maybe it's hang gliding culture that's sociopathic and the people who are trying to change it are actually the best adjusted ones?
Zack C - 2013/02/10 00:41:49 UTC

Paul, I don't think you're following me, or perhaps I'm not following you. Do you think it was a big deal for Zack M when his weak link broke?
Of course not. I think he's been pretty clear...

http://www.hanggliding.org/viewtopic.php?t=26870
weak links
Paul Hurless - 2012/08/14 18:13:13 UTC

Failing to be ready to immediately land if a weak link breaks is a very basic pilot error.
...on this issue in the past. And, hell, Zack DID after all manage to park the glider on the runway right side up after a couple of rotations with little damage and was still conscious for a bit afterwards.
Paul Hurless - 2013/02/10 05:47:51 UTC

In general, no, I don't think that a weak link break is a big deal. In the case of the incident in Florida, I wasn't there to see it and I don't know all the details. I can't honestly make any claims about what happened and neither can anyone else who wasn't there.
http://www.ushawks.org/forum/viewtopic.php?f=2&t=818
Peter (Linknife) Birren
Peter Birren - 2011/11/27 01:49:22 UTC

No, I'm not going to comment on Arlan's accident and you really ought to quit as well because neither you nor I were there.
Tad Eareckson - 2011/11/27 04:47:34 UTC

And yet ANOTHER never fails indicator that you're dealing with someone with a brain half the size of a walnut.
You're ABSOLUTELY RIGHT, Paul. I mean, how do we REALLY know this guy even crashed? All we have are these "words" on our screens. And do we REALLY know what happened at Gettysburg, July First through Third, 1863? I mean NONE of us were THERE.
Blaming equipment failure or any other cause from only the limited information posted instead of firsthand knowledge is B.S.
Goddam right! And don't get me started on this Holocaust thing!
michael170 - 2013/02/10 06:20:15 UTC
Paul, I don't think you're following me...
Try posting some moronic crap, see if that helps.
See? He's not just parroting his sociopathic mentor - he's coming up with good material all on his own! (Wish I had thought of that one.)
...or perhaps I'm not following you.
God, I hope not.
Do you think it was a big deal for Zack M when his weak link broke?
Paul doesn't do thinking.
Paul Hurless - 2013/02/10 06:58:14 UTC

Nobody else needs to post moronic crap, you're already doing enough of that.
Good comeback, Paul.
Dennis Cavagnaro - 2013/02/10 14:09:21 UTC

Hey guys,
This is a thread about a persons life... can we leave this matter to the next thread?
No Dennis. This is a thread about a person's DEATH. And some of us tried repeatedly to have polite rational discussions to address the factors that contributed to it. But those discussions were repeatedly ignored, derailed, sabotaged by total morons like Paul, Craig, and Kinsley and total assholes like Davis, Rooney, and Ryan.

There are a lot of motherfuckers who should've been arrested and charged for this one but - unfortunately - that ain't gonna happen. So expect the conversations to get pretty ugly if you wanna see us start doing things differently and getting different results.
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Re: Weak links

Post by Tad Eareckson »

http://www.chgpa.org/forums/viewtopic.php?f=2&t=5702
Fatal accident at Quest
Mark Cavanaugh - 2013/02/08 04:20:23 UTC

I'm so sorry to hear this news, especially on the heels of that too-fun-and-funny video featuring Zach (I shared it with many!). What a loss.
Don't worry, Mark. I'm sure somebody else will come along and make more fun and funny videos.
And I'm so sorry that you and Paul have the sad task of conveying what happened.
FUCK LAUREN AND PAUL. If they weren't a couple of goddam incompetent, irresponsible, negligent halfwits that wouldn't have happened.
My condolences to Zach's family & friends, and to the two of you.
Shove it up your ass. If you didn't view your job as a moderator as being one of forcing harmony in your little inbred cult of pigfuckers I'd have had a much better chance of preventing that one.
I hope that something positive/proactive, something which could help reduce the risk of freakish accidents, might ultimately emerge. It might make such a tragic loss a tiny bit easier to bear...
I'm kinda hoping that somebody who wants your wallet will shoot you in the back of the head, CHGA will get a new moderator who isn't a useless goddam sack of shit, he'll read and the "Weak link question" thread:

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600

unlock it, end and apologize to me for my illegal "three month suspension", ban Rooney for life, and condemn Ridgely for all the abuses which set this one up.

But I'll settle for you getting shot in the back of the head.

P.S. Really great discussion y'all are having over there about this one.
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Re: Weak links

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=28290
Report about fatal accident at Quest Air Hang Gliding
Davis Straub - 2013/02/11 04:08:10 UTC

The biggest safety issue at the 2013 Worlds was pilots coming off their carts stalled.
Was it, Davis?

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

Here is the requirement from the 2007 Worlds local rules (which I wrote) for weaklinks:
Pilots must use weaklinks provided by the meet organizers and in a manner approved by the meet organizers. All weaklinks will be checked and use of inappropriate weaklinks will require the pilot to go to the end of the launch line to change the weaklink.

Weaklinks will consist of a single loop of Cortland 130 lb Greenspot braided Dacron Tolling line and should be placed at one end of a shoulder bridle.
At the 2008 Forbes Flatlands Greenspot for the first time was used as the standard weaklink material (thanks in large part to the efforts of Bobby Bailey). We applaud these efforts to improve the safety of aerotowing by using a better weaklink material.
http://www.youtube.com/watch?v=MlIGsgNFRWM


Sounds like you've eliminated all opposition to Bailey designed lockout preventers / emergency/backup releases / pitch limiters and can now move on to more important safety issues.

Watchya got on tap for 2014? Backup loops or hook knives?

Excluding Russians, how many competitors were equipped to be able to abort...

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

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.
...in emergency situations?
We just drilled it into them day after day that they had to pull in right as the cart started to roll and get their chests over their base tubes and then come off the carts pulling in even further.
Good job Davis! Way to address those major safety issues. It's a travesty that USHGA hasn't yet recognized you with one of those Safety Awards they're always pinning on the chests of lotsa other serial killers in the sport.

So sounds like you didn't have a lot of people towing two point.
The carts came with their back cradles all the way down and we immediately lifted them up a notch or two to get the gliders angle up high enough to get the pilots up near their base tubes when hanging without holding onto the bar.
Amazing how much we've progressed in the past couple of decades - thanks to the tireless work of people like Russell, Paul, Lauren, Mitch, Mark Frutiger, and the late Zack Marzec.
The pilots got much better after a couple of days.
Super Davis. World competitors advanced so much they could've probably gotten their AT signoffs. How many of them were using adequate wheels?

Given that we bloody well know that everyone and his dog was flying one point (the vast majority on bent pin barrel releases) and Davis Links, what percentage of them would've been able to land softer than Zack did a couple of weekends ago in identical circumstances?

What the fuck does this idiot post have to do with the topic? Clumsy goddam attempt to derail the discussion.
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