Kite Strings

Manned Kiting
The Basic Handbook of Tow Launched Hang Gliding
Daniel F. Poynter
1974

"The greatest dangers are a rope break or a premature release." - Richard Johnson

Obviously. And we're not using weak links but we've got releases that don't stink on ice and we're not breaking gliders if we're not using total morons as boat drivers.

Then in December of 1980 Saint Donnell of Kingsville submits his flavor of faith based aviation to Hang Gliding magazine and tells us that releases that stink on ice are perfectly acceptable as long as...

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," and that "More people have been injured because of a weak link than saved by one." Well, I for one have been saved by a weak link and would not even consider towing without one. I want to know without a doubt (1) when I am pushing too hard, and (2) what will break when I push too hard, and (3) that no other damage need result because I push too hard.

In skyting we use a simple and inexpensive strand of nylon fishing line which breaks at the desired tension limit. There is no possible way for it to jam and fail to release when the maximum tension is exceeded. Sure, it may get weaker through aging or wear and break too soon, but it cannot get stronger and fail to break. If it does break too soon, so what? We simply replace it with a fresh one.

...we have a piece of fishing line in our system which blows, before we can get into too much trouble, at about the bottom end of what the FAA permits for sailplanes or, preferably, so it will blow WAY before we can get into too much trouble...

A properly designed weak link must be strong enough to permit a good rate of climb without breaking, and it must be weak enough to break before the glider gets out of control, stalls, or collapses. Since our glider flies level with a 50 pound pull, climbs at about 500 fpm with a 130 pound pull, and retains sufficient control to prevent stalling if a weak link breaks at 200 pounds pull, we selected that value.

...significantly off the bottom end.

And, after well over a decade and a half of mountains of evidence that this approach is completely full of shit, we have the excellent book...

Towing Aloft - 1998/01

A weak link is the focal point of a safe towing system.

A weak link is 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.

A weak link is 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.

"It is infinitely better to have a weak link break too soon rather than too late."
-- Towing Proverb

A weak link is a fuse that protects the equipment--your body!--on an overloaded circuit.

Always use a weak link when towing--WEAK LINKS SAVE LIVES.

Of course, your weak link should break before the lockout becomes too severe, but that assumes a properly applied weak link.

...Towing Aloft, by Dennis Pagen and Bill Bryden, reinforcing this now Industry Standard crap.

Back then we were all supposed to test our fishing line...

It is imperative that you make and test your own weak links on a test rig to know at what point they break. You should make and test at least 10 weak links. They will all break at slightly different points, but measure them and find the average. Also compare several of the highest and several of the lowest breaking values to the average. If they differ by more than 10% you do not have a reliable and predictable weak link system.

...too make sure it was safely at or below the bottom of the legal sailplane range.

But last summer, when Dr. Trisa Tilletti finally revealed that for the previous eight years we had been covered by sailplane regulations which made the fucking standard aerotow weak link everybody was being forced to use illegally light for damn near all of our flights...

Dr. Trisa Tilletti - 2012/06

TRACY: 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.

...it suddenly became unfashionable to test loops of fishing line - lest people start finding out that they WERE illegally light and half the strength the aerotowing experts were telling us they were.

I've been effectively kicked out of hang gliding and banned from seven forums partially, largely, or entirely for my opposition to this bullshit, my push to get weak links up to the middle of the safety range, and take the decision of when to terminate a tow...

http://www.hanggliding.org/viewtopic.php?t=26870
weak links

Zack C - 2012/08/19 18:03

The decision of when to terminate a tow should be made by the pilot, not a piece of string.

...away from a piece of string and give it back to the PILOT.

I've just looked back at the 246 posts "Weak link question" thread...

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

...at my old club forum, currently back on Page 72...

http://www.chgpa.org/forums/viewforum.php?f=2&start=1775

...from which I was "suspended" for three months over four years ago because of my blasphemous attack on the Sacred String and the Douchebag Disciples of Ridgely Rooney.

Those motherfuckers didn't just permanently suspend me. I see now that they locked the topic - well after I had been removed as a threat to their religion. Just can't be too careful on this 130 pound Greenspot issue.

And guess how many times anybody's raised the issue on that piece o' shit forum since then.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=5426
ECC

John Dullahan - 2012/06/10 16:44:57 UTC

Paul Vernon's accident, as Matt described earlier, brought our the local press, and reporters interviewed some pilots and filmed some of the takeoffs, weak link breaks, and relights.

Same thing on The Bag Show:

http://www.paraglidingforum.com/viewtopic.php?t=28697
Weak links why do we use them. in paragliding.

Forum Moderators - 2010/02/24 22:02:46 UTC

We, the Moderators, feel that weak links are an important topic. In our view Tad Eareckson's posts have discouraged others from taking part in this discussion, so, after several warnings, he has been banned. His most recent post, after this topic was locked, is here. We are happy to lift the ban if we come to the view that Tad has further positive contributions to make - please contact us by PM or by email if you feel that this is the case.

Find somebody questioning BHPA's wisdom on regulating for insanely light weak links to protect paragliders (and hang gliders) from stalls and lockouts after that.

Hang Gliding magazine...

Dave Broyles - 1990/11

I talked to a lot of pilots at Hobbs, and the consensus was that in the course of Eric Aasletten's accident, had a weak link break occurred instead of the manual or auto release that apparently did occur, the outcome would have been the same. Under the circumstances the one thing that would have given Eric a fighting chance to survive was to have remained on the towline.

The weak link breaking strength should be between 100% and 150% of the combined weight of the glider and pilot being towed, but each pilot should be totally responsible for his own weak link.

Find a recommendation for a weak link in excess of one G in the twenty-two plus years after that one.

The patterns...

- Pushing 1.5 is taboo behavior.

- Nobody in positions of control or authority condemns 130 pound Greenspot and/or pushes 1.5. What little condemnation and pushing occurs is done from the lower ranks and disenfranchised.

- If you:
-- push 1.5 you'll be attacked and branded as an unhinged and dangerous Tad clone
-- start scoring points you'll be ignored by the establishment
-- score too many points you'll be locked down, banned, blackballed, made an example of.

- After someone is dealt with there won't be any more discussions of...

http://groups.yahoo.com/group/hhpa/message/9360
Hook knives and other inventions

Zack C - 2010/02/03 21:07

I've had weak links break on aerotows for seemingly no reason a number of times. I feel that this is dangerous and am suspicious of the wisdom of using 130 lb Cortland Greenspot for every pilot in every configuration.

...the wisdom of using 130 lb Cortland Greenspot for every pilot in every configuration.

Too many scumbags in control whose professional reputations will be fucked and who will be opened up to liability issues if people start realizing the emperor is naked.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=4931
Zapata

Pete Lehmann - 2011/06/24

Blood on the Tracks

BJ Herring's intention was to attempt a gigantic world-record distance triangle of 260 miles, Mike Barber needed to test fly his new glider locally, while the Brazilians too wanted to do some gear-sorting and experience the tow operation. In the end, the soft lift and constant cross wind resulted in BJ'’s triangle being truncated into an out’n’back to Laredo (circa 80 miles), Mike’'s test flight proved his glider’'s pitch to be badly out of trim, something that may have contributed to his belly-flop landing on the runway, and the Brazilians had a bunch of broken weak links, part of an unusual number that have been experienced here.

And then there's my weak link break. I had been looking forward to attempting an unusual eighty mile flight to the south east along the Mexican border towards McAllen. But the instant I came off the cart my weak link broke. That shouldn'’t have been a problem as I had good speed to transition to a landing. However, I had zipped up my harness a bit too far and couldn’'t unzip it in the seconds available to me.

Still in my harness, I opted to belly land on the runway. Unfortunately the repaved runway has an extraordinarily coarse texture, that of a heavy grit sand paper, which resulted in my harness and knee being shredded. The harness can be fixed with Shoe Goo, but the knee required three stitches to pull together the resulting mess. The doctor who treated me at the clinic was sufficiently impressed by it to take some pictures for his colleagues. I was extraordinarily lucky, and can walk well and should be flying in a couple of days.

Pete Lehmann - 2011/06/25

The morning began with Zapata'’s characteristic clouds and a perhaps undue general optimism. With my bandaged leg I had decided to take a mental health vacation, but David and I went to the field to help the others fly.

Moral of the story..
Make sure your harness isn't zipped up a bit too far when you're launching on a Davis Link.
Hey Pete...
How much worse off would you have been if your harness had been zipped up all the way?
P.S. Fuck you.

A Zack gets killed at Quest Air, the people who've been perfecting aerotowing for twenty years...

http://groups.yahoo.com/group/flyhg/message/17223
Pilot's Hotline winter flying

Mark Frutiger - 2013/02/03 13:41

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

Zach hit it and went high and to the right. The weak link broke at around 150 feet or so and Zach stalled and dropped a wing or did a wingover, I couldn't tell. The glider tumbled too low for a deployment.

Out of respect for friends and family, I'd ask that if you have a need to more, please call me directly at 585-737-9894 or email me privately instead of posting publicly.

Thank you

...and all I care about is that it wasn't OUR Zack.

Zack Marzec - Libertyville, Illinois - 88356 - H4 - Jon Thompson - 2012/02/11 - Exp: 2013/06/30
- AT FL LGO TAT 360 AWCL CL FSL RLF TUR XC
- ADV INST, TAND INST
- Exp: 2015/05/23 - ADV INST
- Exp: 2015/03/14 - TAND INST

http://media.nbcchicago.com/images/654*369/zachary+marzec.jpg

http://c2.staticflickr.com/2/1482/25711447570_4f88ab6e69_o.jpg


This is gonna be so much fun watching the way these motherfuckers try to hang everything BUT the standard aerotow weak link on this one...

- Put weak links on BOTH ends of the bridle and thus doubled the required breaking strength, nullifying the purpose of the weak link as a safety element which is to break before you can get into too much trouble.

- Tried to fix a bad thing and didn't want to start over.

- Sprogs were set too low.

- Tested positive for marijuana.

And it happened on Groundhog Day! Maybe we'll get to see a few repetitions of this one for a while this year.

http://www.hanggliding.org/viewtopic.php?t=12443
AT regs

Richard Bryant - 2009/06/12 14:39:23 UTC

If the FAA takes your suggestions and makes every pilot, every aerotow operation, possibly every truck or scooter tow operation in the US adhere to strict regulations on our sport (with your fingerprint on it), I'm wondering how many flight parks will BAN YOU from enjoying their services.

All of them, motherfucker. But if my proposals had been followed - or possibly even if the existing FAA minimum weak link ratings had been enforced - this guy would still be alive. And the cost increase would've been the penny or so it would've taken to buy a few centimeters worth of thicker fishing line.

Out of the tens of thousands of tows a year, whether they be by aerotow, truck or scooter, how many failures have occurred due to the current release methods?

Tad Eareckson - 2009/06/12 19:39:52 UTC

I don't know, what's a failure? Somebody killed, hurt, bent downtube, skinned knee, close one? Is something that would have definitely killed someone at 150 feet OK 'cause it happened at 1500 with no repercussions?

http://www.youtube.com/watch?v=WFAPpz6I6WU


http://groups.yahoo.com/group/flyhg/message/17223
Pilot's Hotline winter flying

Mark Frutiger - 2013/02/03 13:41

The weak link broke at around 150 feet or so and Zach stalled and dropped a wing or did a wingover, I couldn't tell. The glider tumbled too low for a deployment.

The following from spark (Allen Sparks) briefly appeared as Post 3604 on this thread at 2013/02/04 00:06:24 UTC before being deleted by its author:

...and all I care about is that it wasn't OUR Zack.

What a callous, heartless, sad comment.

... and if it were 'your' Zack, I have zero doubt that you would exploit his misfortune to further your twisted agenda.

I'm working on a response.

What a callous, heartless, sad comment.

Ya wanna know what's REALLY callous, heartless, sad?

Watching the carnage created by this decades old bullshit of using 130 pound Greenspot fishing line as a lockout preventer, a substitute for a release that doesn't stink on ice, and doing NOTHING about it - the way you have.

I've worked my ass off for half a dozen years to get that crap out of circulation and my thanks from the incompetent scum at Ridgely, Quest, Lockout, Cloud 9, CHGA, USHGA, paragliding, you name it has been to get pissed all over, deleted, banned, ostracized, blacklisted, and attacked in every imaginable way.

I've gotten a little support from a few sane people here and there and Zack Marzec wasn't one of them. He undoubtedly violated FAA safety regulations, he let a piece of string make the decision of when to terminate the tow, it made the wrong decision, he became a very valuable statistic. Tough. Not everyone is cut out to be a PILOT.

... and if it were 'your' Zack, I have zero doubt that you would exploit his misfortune to further your twisted agenda.

There's no way in hell it's gonna be OUR Zack. I deprogrammed him...

Zack C - 2010/12/13 04:58:15 UTC

I had a very different mindset too back then and trusted the people that made my equipment. Since then I've realized (largely due to this discussion) that while I can certainly consider the advice of others, I can't trust anyone in this sport but myself (and maybe the people at Wills Wing).

...and...



...equipped him. If he dies as a consequence of a weak link failure it's gonna be the one right behind some douchebag Dragonfly driver.

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

Jim Rooney - 2008/11/20 22:25:38 UTC

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.

And then you can have zero doubt that I'm gonna spend a good chunk of the rest of my life making his as miserable as possible to further my twisted agenda.

My "twisted agenda", dude, is to rescue this sport from pigfuckers like Bill Moyes, Bobby Bailey, Dennis Pagen, Dr. Trisa Tilletti, Matt Taber, Davis, Bo Hagewood, Adam Elchin, and your good buddy Jim Rooney and prevent Zack Marzec reruns.

Real interesting that you're going after Yours Truly for not giving a much of a rat's ass that this hang gliding equivalent of a drunk driver killed himself by doing the hang gliding equivalent of driving into a telephone pole at eighty miles an hour but you're giving a free pass to all the pigfuckers who taught him that a high Blood Alcohol Content makes the flight safer and got him good and liquored up right before he got on the cart.

P.S.

Zack Marzec - Libertyville, Illinois - 88356 - Exp: 2013/06/30 - H4 - 2012/02/11 - Jon Thompson
- AT FL LGO TAT 360 AWCL CL FSL RLF TUR XC
- ADV INST - Exp: 2015/05/23
- TAND INST - Exp: 2015/03/14

If this guy had been been a Hang Twoish victim of the system - like Jeremiah Thompson or Roy Messing - I'd have been A LOT more sympathetic.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3173
somewhat predictable accident at Highland

Marc Fink - 2008/04/21 23:54:28 UTC

This forum needs a dickhead release.

Allen Sparks - 2008/04/22 00:22:17 UTC
Evergreen, Colorado

I agree, but if the release failed, it would be quite painful ... emasculating ... and debilitating
We would need a weaklink, just in case

Allen Sparks - 2008/04/19 01:38:55 UTC

If accidents were 'somewhat predictable', I'd bet we would have fewer
_hit happens. There are no recipes that prevent it.

So what do you think, Allen? Just another case of "shit happens"? No recipes to prevent it?

If we hit a bit of lift shortly after launch there's a fifty/fifty chance that our Rooney Link will fail and we'll go into an unrecoverable stall?

I wonder how long it's gonna take the USHGA / Flight Park Mafia machinery to figure out how to paint this guy as an incompetent bozo sorely in need of a some Cone of Safety training from Dr. Trisa Tilletti.

http://www.facebook.com/pages/Quest-Air-Hang-Gliding/139425185973

Yesterday at Quest we lost our good friend, Zach Marzec, in a hang gliding accident. We are all in shock and heartbroken here and are all pulling together to support his girlfriend, Clara. We will post more about the accident in days to come but for now I will say that conditions were very benign with light winds and blue skies. The accident occurred low on tow when Zach apparently hit very turbulent air possibly caused by a dust devil without the dust to make it visible. It appears that his glider was in good, flyable condition and rigged properly. We are all just sick.

Another thought....

http://www.youtube.com/watch?v=-i4owd0akd0


He's undoubtedly flying one point, or, as Davis and his Quest douchebag buddies refer to it, "pro tow". And, as we all well know, it takes a pro of extraordinary ability...



http://www.flickr.com/photos/meaneyman/130742003/

...to be able to stuff the bar with results comparable to what a Hang Two can flying two point, or, as Davis and his Quest douchebag buddies refer to it, "three point".

Dennis Pagen - 2005/01

I hung on and resisted the tendency to roll to the side with as strong a roll input as I could, given that the bar was at my knees. I didn't want to release, because I was so close to the ground and I knew that the glider would be in a compromised attitude. In addition, there were hangars and trees on the left, which is the way the glider was tending. By the time we gained about sixty feet I could no longer hold the glider centered--I was probably at a twenty-degree bank--so I quickly released before the lockout to the side progressed. The glider instantly whipped to the side in a wingover maneuver. I cleared the buildings, but came very close to the ground at the bottom of the wingover. I leveled out and landed.

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

Yeah, keep on doing the same thing and expect to keep on getting away with it.

Beginning of Day Three now and still no mention of the Davis Link as a factor.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=5702
Fatal accident at Quest

CF (Dunegoon) - 2013/02/03 13:32:04 UTC

I think some of you might have known Zach. Condolences to family and friends.

A hang glider from Illinois died Saturday after crashing on the runway of a rural south Lake County airfield.

The Lake County Sheriff's Office identified the victim as 27-year-old Zachary Marzec.

According to Marzec's Facebook profile, he is a hang-gliding instructor and he has several dozen photos of himself hang gliding with friends. Deputies say something went wrong as Marzec was in flight and caused the hang glider to go down at Quest Air Hang Gliding's airfield.

Maybe it had something to do with the Bailey Link breaking...

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," and that "More people have been injured because of a weak link than saved by one."

...at the worst possible time, when the glider was climbing hard in a near stall situation.

No one at the business could be reached after the crash.

No shit. And good luck getting some straight answers from those assholes when you do have them cornered.

The crash happened at about 3:20 p.m. He was taken to South Lake Hospital, where he died. Jim Vachon, a spokesman for the Lake County Sheriff's Office, said an investigation is ongoing into the accident and what exactly happened is unknown.

Yeah. And I have every confidence that it will be conducted with the same thoroughness of the one into the "accident" that killed Jeremiah Thompson.

Bacil Dickert - 2013/02/03 18:01:12 UTC

From the Big Walker list...

http://groups.yahoo.com/group/skywacker/

...it was reported that he was flying a Moyes Xtralite, got hit by strong lift that pitched the nose up radically and broke the weak link. The glider tumbled and fell to the ground.

- That's a good bit more dramatic than what Mark Frutiger reported.
- So why did the weak link break, Bacil? Was the glider starting to get dangerously overstressed?
- How much worse off would he have been with a weak link in the middle or at the top end of the legal range that held?

He was the pilot in the "A Whole New World" video released just over a month ago. Tragic. Condolences to family and friends.

Fuck his "friends". They're the people who got him killed.

http://www.kitestrings.org/post3556.html#p3556

Tad Eareckson - 2013/01/22 05:21:02 UTC

http://www.chgpa.org/forums/viewtopic.php?f=2&t=5659
Preflight people, please?

Danny Brotto - 2012/12/21 13:10:52 UTC

This is a cute video link posted on the ozreport.

http://www.youtube.com/watch?v=ZLTDPeB55ek


Is it just me or is the gal's helmet not buckled? The straps seem to be blowing in the wind. I'm impressed that it stayed on!

...
- The primary weak link is heavier than the tug's.
- None of those Quest douchebags has a freaking clue as to the strengths of their weak links or even their purpose.
- They're:
-- telling students that installing weak links on both ends of bridles doubles the towline tension required to blow them

Called that one eleven days and fifteen hours before the guy bought it. Am I good or what!