I don't feel that it is valid to rely on the FAA as an authoritative voice in this discussion. Perhaps if you linked to the research and justification for the FAA's position, that would be more useful.
Recommended breaking load of a weak link is 1g. - i.e. the combined weight of pilot, harness and glider (dependant on pilot weight - usually approximately 90 to 100 kg for solo operations; or approximately. 175 kg for tandem operations).
Here is the requirement from the 2007 Worlds local rules (which I wrote) for weaklinks:
Pilots must use weaklinks provided by the meet organizers and in a manner approved by the meet organizers. All weaklinks will be checked and use of inappropriate weaklinks will require the pilot to go to the end of the launch line to change the weaklink.
Weaklinks will consist of a single loop of Cortland 130 lb Greenspot braided Dacron Tolling line and should be placed at one end of a shoulder bridle.
At the 2008 Forbes Flatlands Greenspot for the first time was used as the standard weaklink material (thanks in large part to the efforts of Bobby Bailey). We applaud these efforts to improve the safety of aerotowing by using a better weaklink material.
We had six weaklink breaks in a row at Zapata this year. Russell Brown (tug pilot, tug owner, Quest Air owner) said go ahead and double up (four strands of Cortland Greenspot).
Something to bear in mind... the tug's weaklink is three strand.
For clarity... A normal single loop weaklink would be considered two. A tandem double loop is considered four.
In the tandem setup, the "weaklink" in the system is at the tug end, not the glider.
Ya'll seem to be missing this.
Once you go beyond three strand... you're not using a weaklink. If the weaklink goes, you're getting the rope.
How 'bout YOU link to the research and justification for the:
- the HGFA's recommended breaking load of a weak link of one G - the combined weight of pilot, harness, and glider
- mandatory use of a single 130 pound Greenspot on a one or two point bridle end for all solo gliders
- use of a double loop of 130 on all tandem glider bridles and a three strander on all Dragonflies
This fall at Ridgely, I had a weak link break at maybe fifty feet. I thought I was going to have to land in the soybeans - the very tall soybeans - when I looked at my angle. But, my glider stalled quite dramatically almost instantly (hard not to stall when you have a break), and dove towards the ground (a bit disconcerting from so low).
I came off the cart smoothly, but at a hundred feet, started getting slammed. I tow lots, and I will tell you I have never felt anything like this before. Ginny leapt sideways and would go slack and then violently shudder. Jim hung onto the plane and I hung onto her basetube, but at four hundred feet my pussy-##s weak link broke. Great. Now I had to land in the monster that had just attacked the runway. My glider set me down neatly, but adrenaline was practically spilling out my eyeballs by then.
I rarely break weak links -- in fact, I believe the last one was some two years ago, and I have never broken one on a tandem (probably because I am light and also because I change them whenever they show any signs of wear). They are a good thing to have, though!!
We will post more about the accident on the Quest FB page in the coming days. For now I will say that it appears to have been a fluke accident. Weather conditions were very benign with light winds and blue skies and the glider was in good airworthy condition. We are all sick about this untimely loss of our good friend, Zack.
Lauren Eminently-Qualified-Tandem-Pilot Tjaden - 2013/02/07 23:56:42 UTC
I am posting the report my husband, Paul Tjaden, just wrote about Zach Marzec's death at Quest. It is a great tragedy to lose someone so young and vital. We are sick about it, and our hearts go out to his friends, family and loved ones.
The launch started on the main runway at the north end (2,000 feet long) and was normal until at approximately fifty feet in altitude when the tow plane hit extremely strong lift elevating it quickly and abruptly. Because of the length of the tow line, it was a few seconds later when Zach's glider entered the same strong lift and he was at an estimated 100 to 150 feet in altitude at this time.
When the lift/turbulence was encountered, the weak link on the tow line broke as the nose of the glider pitched up quickly to a very high angle of attack. Apparently, the glider stalled or possibly did a short tail slide and then stalled and then nosed down and tumbled. Eye witnesses said the glider tumbled twice and then struck the ground with the base tube low.
- You're light - well under 180 pound Zack Marzec.
- You use the same Rooney Link that Zack does and you change it frequently to keep it at optimal one-size-fits-all performance.
- But, nevertheless, you have them fail at fifty feet when nothing's going on. (And nothing was going on 'cause if there had been you'd have fuckin' told us.)
- And at fifty feet with nothing going on your pussy-##s weak link broke and dumped you almost instantly into a quite dramatic and disconcerting stall.
- And a little over a decade later you assholes are towing Zack Marzec up with the same Rooney Link on a one point bridle 'cause Zack's a pro who can react to a situation so fast that he doesn't need a keel attachment to help him keep the nose down.
- And he gets slammed by a monster thermal and when the nose of his glider was pitched up quickly to a very high angle of attack...
Donnell Hewett - 1981/10
Now I've heard the argument that "Weak links always break at the worst possible time, when the glider is climbing hard in a near stall situation"...
...his pussy-##s Rooney Link blew.
- And, big surprise, he's dumped almost instantly into a quite dramatic and disconcerting stall.
And now, close to three months after his pussy-##s Rooney Link blew and dumped him almost instantly into a quite dramatic and disconcerting stall which progressed to a tailslide and tumble, none of you SLEAZY DUPLICITOUS CRIMINALLY NEGLIGENT MOTHERFUCKERS has the SLIGHTEST CLUE what the problem was - let alone any idea on how to address it.
Lauren Tjaden - 2011/08/01 02:01:06 UTC
I rarely break weak links -- in fact, I believe the last one was some two years ago, and I have never broken one on a tandem (probably because I am light and also because I change them whenever they show any signs of wear). They are a good thing to have, though!!
Go ahead, Lauren Eminently-Qualified-Tandem-Pilot Tjaden... Tell us a few of the GOOD things that happen when your pussy-##s Rooney Links blow. And DO make them good enough to cancel out some of your own experiences with them.
And DO keep using your pussy-##s Rooney Link 'cause it's a good thing to have and the more times your useless goddam ass gets dumped almost instantly into quite dramatic and disconcerting stalls the higher the probability that you're gonna leave the runway in a body bag and the more fun I'm gonna have watching the surviving Quest scumbags trying to write you off as another inexplicable freak accident.
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.
I rarely break weak links -- in fact, I believe the last one was some two years ago, and I have never broken one on a tandem (probably because I am light and also because I change them whenever they show any signs of wear). They are a good thing to have, though!!
I came off the cart smoothly, but at a hundred feet, started getting slammed. I tow lots, and I will tell you I have never felt anything like this before. Ginny leapt sideways and would go slack and then violently shudder. Jim hung onto the plane and I hung onto her basetube, but at four hundred feet my pussy-##s weak link broke. Great. Now I had to land in the monster that had just attacked the runway. My glider set me down neatly, but adrenaline was practically spilling out my eyeballs by then.
- Your pussy-##s Rooney Link holds while a monster thermal grabs you, violently tosses and shakes you all over the sky, and reduces you to a nervous wreck.
- Then, after you've got everything under control, it blows for no reason and forces a landing in potentially violent conditions.
- And then, presumably, you're gonna relaunch right away and risk:
-- something similar, maybe worse, going up;
-- another:
--- pussy-##s Rooney Link pop
--- forced landing in potentially violent thermal conditions
It's more of this crappy argument that being on tow is somehow safer than being off tow.
...more of this crappy argument that being on tow is somehow safer than being off tow.
- So just how far out of whack do you need to get for your pussy-##s Rooney Link to fulfill its function? I guess whatever it is you wouldn't be able to get into too much trouble because that would be - by definition - too for out of whack.
- Are you sure your pussy-##s Rooney Link was really light enough to fulfill its function? Maybe you shouldn't change them when they start showing signs of wear. Maybe it would be a good idea to just use hand-me-downs from other people who change them whenever they show any signs of wear - preferably people about whom you don't really give a rat's ass.
- I thought you were supposed to...
Quest Air...
ALWAYS RELEASE THE TOWLINE before there is a problem.
...always release the towline before there was a problem. Really hard to believe anyone would ELECT to remain an tow while HAVING MULTIPLE problems. What was your motivation?
- If the glider's getting thrown all over the sky like that with your pussy-##s Rooney Link failing to fulfill its function doesn't that make things terribly dangerous for the tug?
- I'm really surprised that for the benefit of the both of you your driver didn't...
Whatever's going on back there, I can fix it by giving you the rope.
...fix what was going on back there by giving you the rope.
- Is it conceivable that if some of that shit had hit you down low that your pussy-##s Rooney Link could've fulfilled its function when it decided you were too far out of whack and...
Lauren Tjaden - 2003/12/14
This fall at Ridgely, I had a weak link break at maybe fifty feet. I thought I was going to have to land in the soybeans - the very tall soybeans - when I looked at my angle. But, my glider stalled quite dramatically almost instantly (hard not to stall when you have a break), and dove towards the ground (a bit disconcerting from so low).
...your glider might have stalled so instantly, dramatically, and disconcertingly that it would've continued diving INTO - not just TOWARDS - the ground?
- Paul says:
Paul Tjaden - 2013/02/07
I have witnessed countless others have weak link breaks with no serious problems. We train aero tow pilots how to handle this situation and I am certain that Zach had also encountered this situation many times before and knew how to react properly.
and yet when your pussy-##s Rooney Link popped at fifty feet you stalled quite dramatically almost instantly and experienced a disconcerting dive towards the ground.
-- So how much air did you eat up before you recovered?
-- What's the:
--- maximum altitude loss a Quest trained aerotow pilot can experience when his pussy-##s Rooney Link pops?
--- minimum altitude at which a pussy-##s Rooney Link can pop?
-- How much shit did it take to fill up you, Paul, and the rest of you Quest douchebags?
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.
I rarely break weak links -- in fact, I believe the last one was some two years ago, and I have never broken one on a tandem (probably because I am light and also because I change them whenever they show any signs of wear). They are a good thing to have, though!!
Lessee Lauren...
- The function of the weak link 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.
- That can save a glider, a tug driver, or, more often, a hang glider pilot who does not get off of tow when he or she gets too far out of whack.
- But YOU rarely break weak links. In fact, you believe the last one was some two years ago.
- And you've never broken one on a tandem.
- This is probably because you're light and also because you change them whenever they show any signs of wear.
- It sounds a bit to me like you don't really want them to break.
- And Russell Brown, a founder of Quest Air 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 and owner of the first 914-powered Dragonfly ever made...
Dr. Trisa Tilletti - 2012/06
It's not that it doesn't happen, but it is a rare occurrence. 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. Russell owned the first 914-powered Dragonfly ever made--he helped us build the second one, which we still fly. He is the one who, many years ago, showed us the method for making a WT weak link and suggested we use polypropylene rather than Spectra for hang glider V-bridles.
...figured out how get double the strength of a Pre-Tied loop of 130 pound Greenspot using a Wrap and Tie method (seems to me you could just pre-tie 260 pound test to get the same result but I guess that would be dangerous because one would be violating the accepted standard) and further protect it using a polypro bridle which doesn't act somewhat like an impact wrench the way Spectra does.
- So it sounds like Russell's doing everything he's capable of thinking of to keep them from breaking.
- You're:
-- light
-- positioning the knot so that it's hidden from the main tension in the link and excluded altogether from the equation
-- changing your pussy-##s Rooney Links them whenever they show any signs of wear
- Don't all those things add up to a much more dangerous tow for you, your tandem passenger, and your tug driver?
OR...
- Are the facts that you're light, positioning the knot so that it's hidden from the main tension in the link and excluded altogether from the equation, and changing your pussy-##s Rooney Links whenever they show any signs of wear all adding up to move things towards the center of the 0.8 to 2.0 G safety range and making the tow SAFER?
- If that's indeed the case then shouldn't we be putting proportionally heavier weak links on, in ascending order, people like Zack, Paul, and me?
- It even seems like your Dear Friend and Mentor Jim Keen-Intellect Rooney...
Jim has pointed out those that weren't there have no say about what happened to Zach. Jim was there and offers little. Does anyone know if Zach's primary release failed? Or did the WL break before he had time to activate his release?
What kind of release did he have on his glider? Both primary and secondary.
Is the refined scum that inevitably rises to the top in a sport that's controlled by a thoroughly corrupt global commercial industry that owes its continuing existence to massive decades long disinformation campaigns.
...has pointed out those that weren't there have no say about what happened...
- That kinda line is a flag that tells you with a one hundred percent certainty factor that you're dealing with an asshole.
- Those who were "there" are virtually always the LAST people you wanna trust - especially in a towing operation - because there are virtually always conflict-of-interest issues. If:
-- the victim were an asshole or accident waiting to happen then who signed him off and/or why wasn't his rating suspended or revoked?
-- the victim's equipment were junk then who sold it to him and why was he allowed to take off with it?
-- conditions were unacceptably dangerous then why was everyone else in the club flying in them that day?
- Whenever somebody uses that line put him on your list and don't EVER take him off it. (This won't leave you with many friends in this sport but sometimes quality is a lot more important than quantity.)
... to Zach.
ZacK - despite the spelling damn near all of his dearest and most devastated friends prefer.
Jim was there...
No.
...and offers little.
He offers TONS. The problem is that it's all total shit.
Does anyone know if Zach's primary release failed?
Does anyone care?
A car:
- loses it on a turn and smashes into a tree. You don't need to see if the fuel filter was clogged.
- stalls out on the train tracks and has its width reduced by 95 percent. You don't need to see if the master cylinder in the brake system was shot.
I could have taken a new AT qualified Hang Two, tied a fifteen foot length of rope to one of his shoulder straps and the base of his kingpost, replaced the Dragonfly weak link with a quarter inch steel quick link, and he'd have been fine.
There was no reason for a properly rigged glider with a solid connection to the tug to abort the tow.
Does anyone know if Zach's primary release failed?
Depends on what you mean by the terms "primary", "release", and "failed".
Damn near everyone in hang gliding considers the Rooney Link...
I guess the hook knife is my second release? Or is that third release, with the weaklink being a second?
...to be a release and, in an emergency situation...
Towing Aloft - 1998/01
A weak link is:
- the focal point of a safe towing system.
- a very simple device--typically a loop of line--that is intended to break in the event towline tensions exceed a safe or desired threshold.
- required that will not break needlessly in response to moderate thermals, or pilot inputs, yet will break at a low enough point to avoid disaster or excessive pilot panic.
...the primary release and a Rooney Link failure to be an unmitigated success. So I'd say that Zack's primary release "worked"...
Anyway...
Weaklink material... exactly what Davis said.
It's no mystery.
It's only a mystery why people choose to reinvent the wheel when we've got a proven system that works.
...flawlessly. He was an experienced pilot who was unable to maintain the correct tow position (centered, with the wheels of the tug on the horizon)...
The Wallaby Ranch Aerotowing Primer for Experienced Pilots - 2013/04/28
If you fail to maintain the correct tow position (centered, with the wheels of the tug on the horizon), the weak link will break before you can get into too much trouble.
...and the weak link will broke before he could get into too much trouble. What happened next was his problem - but no one can say our proven system didn't work.
Or did the WL break before he had time to activate his release?
NOBODY, at ANY TIME in the course of that tow, had the slightest desire to abort it. The more violent the ride up the better afternoon you're gonna have. There's nothing more depressing than a nice smooth tow. And when the glider got blasted and was standing on its tail the absolute last thing you want...
...is for the tow to be aborted. Going up - at least below the point at which oxygen starts getting to be problematic - is ALWAYS better than coming down.
What kind of release did he have on his glider?
None. That was one of the two factors that got him killed. All he had was a piece o' shit bent pin barrel release...
...on his right shoulder. (At the time Zack uploaded that video, by the way, he had something in the ballpark of twenty hours left to live.)
Both primary and secondary.
The only configuration in which you need a secondary one in which you're using a bridle long enough to wrap at the tow ring.
- A two point - pilot and glider - aerotow bridle is, by definition, long enough to wrap. You need a primary up top at the keel and a secondary at the pilot end.
- There's no excuse whatsoever for using a one point - pilot only - bridle long enough to wrap so there's no need for a secondary.
- There's also no excuse whatsoever for going up with a release which has any possibility of failure - so you don't need a backup. (A favorite tactic of The Industry is to brainwash everyone into believing that a bulletproof release is beyond the scope of human engineering so that it doesn't have to recall the crap they've been putting into circulation for decades that has thirty and ninety percent failure rates in normal and emergency use respectively and be held liable for the fatalities it's caused.)
...are so light and cheap that it's stupid not to have them on both shoulders - ignoring the fact that neither one of them is gonna do you any good in most real emergency scenarios.
- For half safe one point aero you need something like this:
...and really hope we are 'cause it's a beautiful illustration of the two elements that are gonna kill him tomorrow:
- one point "pro tow" bridle because he's such a pro that he doesn't need the glider trimmed properly
- loop of chintzy fishing line at the right end of the bridle to keep him from getting into too much trouble
Other observations...
- cheap:
-- piece 'o shit twin inaccessible bent pin barrels with no load capacity
-- wrap prone grotesquely overlength bridle
- dangerously overlength Rooney Link
- no port weak link - meaning that if he has a wrap after releasing from the right barrel or blowing his Rooney Link he and, most importantly, his port cheap piece 'o shit inaccessible bent pin barrel with no load capacity no longer have weak link protection
Do not overthink this fatality...
Two ten year old kids go out to the park with kites. One is using 130 pound Greenspot for his kite string, the other is using a spool of cotton sewing thread that...
We had six weaklink breaks in a row at Zapata this year.
...breaks every time the wind gusts from eight to ten miles an hour. Which kid is gonna come back home with a kite in better shape and more fun time logged?
This one's a total no-brainer. Less severe but potentially lethal Rooney Link induced stalls like this one are common as dirt and it's absolutely amazing how absolutely amazed people are whenever someone is unable to get things back under control enough in time to survive.
But The Industry will NEVER admit that Zack was killed by the focal point of his safe towing system because it doesn't want the flying public to see that it's had a third of a century's worth of emperors running around stark naked and publishing fourteen page lunatic articles on how to get 130 pound Greenspot to meet our expectations of a standard aerotow weak link. There's a very obvious reason Davis threatened bannings from his closed cult forum and locked down all the relevant discussions.
P.S. If anyone can confirm - or refute - that that's Zack at 4:04 I'd REALLY appreciate it.
And I'd also really appreciate it if someone could extract a full resolution still from from the video at 4:04 - whether or not it's Zack. I don't seem to have any software that can do it.
---
2020/09/14 - Done.
Tad Eareckson wrote:And I'd also really appreciate it if someone could extract a full resolution still from from the video at 4:04 - whether or not it's Zack. I don't seem to have any software that can do it.
Dunno about Macs, but on a PC you can just hit the Print Screen button and paste into any image editor.
Zack
Attachments
[The extension png has been deactivated and can no longer be displayed.]
Thanks.
Yeah, I can do screen shots. But being really anal I was shooting for the original image.
Like the width of that PNG image is 1700 pixels and the max width on the YouTube MP4 video file is 1080.
The Mac OS installation comes with an iMovie application but that didn't seem to do the trick. May hafta get a favor from a Final Cut Pro driver.
Tad Eareckson wrote:Like the width of that PNG image is 1700 pixels and the max width on the YouTube MP4 video file is 1080.
The max height on YouTube is 1080...the width in that resolution is 1920, which was the original resolution of the screenshot (as it's also my monitor resolution). The image I posted is 1700 wide because I cropped out the black bars on the sides.
I can capture frames with my video editing software but I'm not sure how to download an HD YouTube video without installing a browser plug-in. But really, the end result will be identical. In any event, you can't download the originally uploaded video, which will be of better quality (one of the reasons I'm still using Vimeo).
(I just cropped out a bit more of the black bars - we're now down to 1685.)
...I'm not sure how to download an HD YouTube video without installing a browser plug-in.
I archive all videos referenced on Kite Strings at max available resolution using Wondershare AllMyTube which is available in Mac and Windows versions and can be used as a plug-in or stand-alone.
Speaking of which...
A lot of valuable referenced videos have been taken down off of YouTube. Is it possible and legal to make them available by uploading them here as downloabable attachments?
