Weak links

General discussion about the sport of hang gliding
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://www.towmeup.com/shop/weak-links-and-leader-lines/
Online Store / Weak Links and Leader Lines | TowMeUp.com
Stuart Caruk - 2015/01/01

Everybody is free to select the most appropriate strength for a weak link. USHPA recommends 75 - 100% of your inflight load. On our towboats you typically will find only 2 weak links strengths used. We use 250# material for SOLO pilots. When tied in a double grapevine knot, these break reliably around 264 pounds. For TANDEM pilots, we use 300# material. When tied in a double grapevine knot, these break reliably around 384 pounds.
Everybody is free to select the most appropriate strength for a weak link.
- Guess you don't do much aerotowing behind Dragonflies and at pecker measuring contests run by Bill Moyes and Davis Dead-On Straub.

- How exactly DOES one select "the most appropriate strength for a weak link"? What's it supposed to do for us and how reliably will it do it? Are there any tradeoffs involved in lower and higher ratings?
USHPA recommends 75 - 100% of your inflight load.
- What happened to?:
Stuart Caruk - 2011/09/15

Most reliable sources believe that a weaklink should be sized so that it breaks at 75% to 100% of the inflight load.
Did:
-- most reliable sources suddenly start believing something else for some inexplicable reason?
-- USHPA become a more reliable source than most reliable sources?

- Any chance you can explain to us muppets *WHY* USHPA recommends 75 to 100 percent of our inflight loads?

- If USHPA recommends 75 to 100 percent of our inflight loads then is there some reason you shouldn't be shooting for 87.5 percent of our inflight loads to achieve weak link perfection?

- USHGA recommends about twice that - you stupid incompetent lying motherfucker. And now most reliable sources have decided they're very happy with 200 - so how come you're not offering or recommending that?
We use 250# material for SOLO pilots. When tied in a double grapevine knot, these break reliably around 264 pounds. For TANDEM pilots, we use 300# material. When tied in a double grapevine knot, these break reliably around 384 pounds.
- And just what is it you're supposed to be accomplishing with these reliable figures?

- So for a tandem glider of nearly twice the flying weight and capacity of a solo you're upping the weak link rating 45 percent. Wanna explain the "thinking" behind that arithmetic, asshole?
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

Dr. Trisa Tilletti - 2012/06

What we have covered in this article is practical information and knowledge gleaned from the real world of aerotowing, developed over decades and hundreds of thousands of tows by experts in the field. This information has practical external validity. Hopefully, someone will develop methods and technology that work better than what we are using as standard practice today. Like the methods and technology used today, it is unlikely that the new technology will be dictated onto us as a de jure standard. Rather, to become a de facto standard, that new technology will need to be made available in the marketplace, proven in the real world, and then embraced by our sport.
Or people could just suddenly decide the methods and technology used today are total shit, find something else that they think will make them happy, skip all the proving in the real world crap, slap it on and go.

http://www.hanggliding.org/viewtopic.php?t=26870
weak links
michael170 - 2012/08/17 17:01:40 UTC

Zack, let me see if I understand your logic.

You had a thing and it broke needlessly.
You didn't want the thing to break needlessly.
You replaced the thing with a stronger thing.
Now the thing doesn't break needlessly.
So Trisa...
This article was peer-reviewed and approved for publication by the USHPA Towing Committee.
Any comment on this from any of the other total douchebags on the USHPA Towing Committee? Is there another fourteen page article on 200 pound Greenspot standard aerotow weak links scheduled for the magazine's Higher Education column anytime soon?
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

Hey Marc...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links
Marc Fink - 2007/05/19 12:58:31 UTC

A 400lb load limit for a solo tow is absurd.

Last year's jihad was against releases--now you're going after weaklinks.

Everyone supports you making efforts to improve things--but in the process you trash the present methods as somehow being an accident waiting to happen.
http://4.bp.blogspot.com/-bRrpHNa68iY/UQ6Pv9gRZyI/AAAAAAAAjTg/Hc22bx5122Q/s2048/20943781_BG1.jpg
Image
You might not actually say it--but the implication is that both the operators and towed pilots are being irresponsible for using faulty equipment and practices.

Do pilots need to constantly review their tow systems? yes. Do weaklinks--being the weakest link in the system, after all--need to be carefully inspected and frequently changed? yes. Do we need to constantly try to improve things? yes. Do we need to scare the daylights out of pilots with doomsday scenarios and suggest punative action for using widely accepted practices before something better comes along? Definitely not.

My apologies to the list for waking this sleeping giant.
http://en.wikipedia.org/wiki/Isoroku_Yamamoto's_sleeping_giant_quote
Isoroku Yamamoto's sleeping giant
The quote is portrayed at the very end of the 1970 film Tora! Tora! Tora! as:

"I fear all we have done is to awaken a sleeping giant and fill him with a terrible resolve."

Although the quote may well have encapsulated many of his real feelings about the attack, there is no printed evidence to prove Yamamoto made this statement or wrote it down.

The line serves as a dramatic ending to the depiction of the Pearl Harbor attack, but it has yet to be verified that Yamamoto ever said or wrote anything resembling the quote. Neither At Dawn We Slept, the definitive history of the Pearl Harbor attack by Gordon Prange, nor The Reluctant Admiral, the definitive biography of Yamamoto in English by Hiroyuki Agawa, contains the line.

Regardless of the provenance of the quote, Yamamoto believed that Japan could not win a protracted war with the US. Moreover, he seems to have believed that the Pearl Harbor attack had become a blunder--even though he was the person who came up with the idea of a surprise attack on Pearl Harbor. It is recorded that "Yamamoto alone" (while all his staff members were celebrating) spent the day after Pearl Harbor "sunk in apparent depression". He is also known to have been upset by the bungling of the Foreign Ministry which led to the attack happening while the countries were technically at peace, thus making the incident an unprovoked sneak attack that would certainly enrage the Americans.
Image

Fuck you and the list - asshole.
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/19.2
Jamie Shelden reporting from Forbes
Jamie Shelden - 2015/01/01 14:35:35 UTC

Great way to start off the year! Nearly half the field made the 144km task to Manilda.
So Davis...

Are we still...

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.
...applauding Davis Dead-On Straub and Bobby Fucking-Genius Bailey for their efforts to improve the safety of aerotowing by using a better weak link material? Are tugs still...

http://ozreport.com/13.238
Adam Parer on his tuck and tumble
Adam Parer - 2009/11/25

Due to the rough conditions weak links were breaking just about every other tow and the two tugs worked hard to eventually get everyone off the ground successfully.
...working hard to get everyone off the ground successfully with weak links breaking about every other tow due to rough conditions? How 'bout...

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

I am more than happy to have a stronger weaklink and often fly with the string used for weaklinks used at Wallaby Ranch for tandem flights (orange string - 200 lbs). We used these with Russell Brown's (tug owner and pilot) approval at Zapata after we kept breaking weaklink in light conditions in morning flights.
...really smooth conditions? How's the...

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Davis Straub - 2011/08/28 15:26:28 UTC

Then again, Russell Brown had us double up behind him after six breaks in a row at Zapata. We couldn't figure out why we had so many breaks so quickly. Maybe just coincidence.
...coincidence problem coming along? Are any of the many of us from up here who decided they were happy with the new 200 pound Cortland Greenspot still equally happy with the 130 I'm assuming the Aussie twats still have on their books down there?
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question
Jim Rooney - 2008/11/24 18:54:27 UTC

I'm confused. I never said the tug's ass was endangered. That's why we use 3strand at the tug's end. Using 4 strand can rip things off (it's happened).
Yeah? So you fucking geniuses discovered that a tow mast breakaway designed to break away at four strand tension broke away at four strand tension? How long did it take you to go to three strand? Were any tow mast breakaways snapped subsequent to the one on 2002/08/17 that dumped William Woloshyniuk and Victor Cox into a double fatal stall?
When forces are achieved that do break a 3 strand, your tail gets yanked around very hard, which does have implications as to the flight characteristics and flightpath.
Wow! You got four and five syllable words into that sentence to convey the illusion that you were actually saying something of substance. Most impressive.
AKA, I have no desire to allow you to have the ability to have that effect on me when I tow you... esp near the ground.
- Ya know what I do when a tug is having an effect on me that I don't desire - 'specially anywhere? I blow my homemade funky shit release. I know it doesn't work 'cause if it did everyone would be using it but I still prefer it to the stuff "designed" by...

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

...Bobby Fucking-Genius Bailey and marketed by Davis Dead-On Straub.

- So just how hard...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=6326
An OK Day at Ridgely
Matthew Graham - 2014/06/09 01:51:11 UTC

I got on the flight line at a little after 1pm behind Sammi. She had a sledder. Then the tandem glider called rank and went ahead of me. The tandem broke a weak link and it took a while to sort out a new weak link. I finally towed around 1:30 and also broke a link at 450'. Back to the end of the line. Actually, my wife Karen let my cut in front of her. Bertrand and Sammi towed again. Each having sledder. The cirrus had moved in and things did not look good. Again I arrived at the front of the line only to have the tandem call dibs. And then the tug needed gas. I thought I would never get into the air...
...was that tandem's tail getting yanked around when that four strander blew and what were the implications for the flight characteristics and path? A bit odd that neither Matthew nor anyone else mentioned anything and there was no incident report published, donchya think?

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

We all play by the same rules, or we don't play.
Morningside decided that they were happy with 200lb weaklink. They changed their tug's link...
What did Morningside change their Dragonfly's weak link to accommodate the 200 they decided they were happy with on solos? A two strand? They don't tow tandems? Why would they need to change the tug's weak link unless they also upped their tandems (making things insanely dangerous for their tug pilots and without telling anyone)? And what would be the point if a four strand will rip off the tow mast breakaway?

C'mon. It's been a long time since we've had the benefit of your keen intellect. Get it in gear and tell us all just how well you have these issues sussed out.
...and they don't just pass the stuff out either.
Like...

http://ozreport.com/forum/viewtopic.php?t=39719
Building hang gliding back up
Tommy Thompson - 2014/11/07 01:33:34 UTC

I'v seen aero-tow sights where even H2 pilots are using 2G weaklinks because they don't want to risk ending up at the back of long line of gliders because of a weaklink break.
...some of these other places are? With total disregard for the safety of their Hang Twos?
If you'd like to know more about it... go ask them.
How strange they don't have anything up on their website. I'd think they'd want as many people as possible to fully understand how much better they're doing things than everyone else to attract more recreational pilots. And I'm really surprised you can't tell us more about it. I was under the distinct impression that...

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

Enjoy your posts, as always, and find your comments solid, based on hundreds of hours / tows of experience and backed up by a keen intellect/knowledge of the issues when it comes to most things in general and hang gliding AT/Towing in particular. Wanted to go on record in case anyone reading wanted to know one persons comments they should give weight to.
...you knew more about everything than anyone.
Steve Davy
Posts: 1338
Joined: 2011/07/18 10:37:38 UTC

Re: Weak links

Post by Steve Davy »

Ever notice how nobody ever suggests that stopping a run, thus killing thrust, just as the glider is starting to fly on a foot launch is a good idea?

I bet that Bob could figure out a way for that technique to make some kind of sense.
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

Safely learning to handle the inevitable rather than trying to come up with some way to avoid the inevitable.
Slope launch practice for aerotowing.
Good with those, Bob?
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question
Jim Rooney - 2008/11/24 18:54:27 UTC

I'm confused. I never said the tug's ass was endangered. That's why we use 3strand at the tug's end. Using 4 strand can rip things off (it's happened).
So why were "we" ever using four strand in the first place?

You fucking geniuses determined that a single loop of 130 pound Greenspot was the perfect one-size-fits-all solo aerotow weak link and thus, obviously, a double loop would be the perfect one-size-fits-all tandem aerotow weak link - since tandems are twice as heavy.

And the only way you could find out that four strand - the lightest weak link Russell Brown later found he could use to get solos airborne in light morning conditions - could rip "things" off was to tow tandems until you killed a couple guys? Bill Moyes and Bobby Fucking-Genius Bailey couldn't specify in the Dragonfly owner's manual the weak link required to protect it from structural damage - the way ever sailplane manufacturer on the planet does? Seems to me like a pretty simple, easy, cheap test - 'specially compared to what's involved for hang glider certification.

And the only way you could address the issue of the "things" being ripped off was to dumb down the weak link? You were incapable of...

http://www.hanggliding.org/viewtopic.php?t=26870
weak links
michael170 - 2012/08/17 17:01:40 UTC

Zack, let me see if I understand your logic.

You had a thing and it broke needlessly.
You didn't want the thing to break needlessly.
You replaced the thing with a stronger thing.
Now the thing doesn't break needlessly.
...replacing them with stronger "things" that didn't break needlessly?

So what's the Dragonfly owner's manual say about weak links now?

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

Morningside decided that they were happy with 200lb weaklink. They changed their tug's link and they don't just pass the stuff out either.
When Morningside decided to change their tug's weak link did they do it in accordance with the specification? Or do you assholes just...
Jim Rooney - 2013/03/04 19:31:36 UTC

The accepted standards and practices changed.
I still won't tow people with doubled up weaklinks. You don't get to "make shit up". I don't "make shit up" for that matter either.
...make shit up as you go along - and keep hoping for the best?
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=1514
towing rig Q
swera - 2015/01/13 07:09:32 UTC

Yes ...a short while after my first solo... I watched an advanced pilot attempt tow even though he had not towed in 2 years, on a new Litesport.. He hit a massive thermal after take off, 60 ft and entered a lockout , with the glider pitched to about flare position, the link broke and he came down nose first killing him instantly..(i remember it like it was yestarday)
This is UNDOUBTEDLY Mike Haas - 2004/06/26, Hang Glide Chicago. Pilot rating, layoff period, glider, incident description all line up. Reads more like Zack Marzec than the other information we've had to date. And that was a two point tow.
Wills Wing / Blue Sky / Steve Wendt / Ryan Voight Productions - 2007/03

NEVER CUT THE POWER...

Image

Reduce Gradually
Increase Gradually
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=28290
Report about fatal accident at Quest Air Hang Gliding
michael170 - 2013/09/19 06:52:50 UTC
SkyTribe - 2013/09/11 22:00:20 UTC

What the hell is with you Michael170. You seem obsessed with accidents?
Try this next time:

What the hell is with you Michael170? You seem obsessed with accidents.
2015/01/26 07:07:55 UTC - Sink This! -- Comet
And your objection is to what? Literacy in general or just literacy in Orion Price's posts? ("SkyTribe" banned 2013/09/16 23:31:13 UTC after a total of 23 posts over the span of eight days for being too much of an asshole for even Jack's asshole sanctuary.)
michael170 - 2015/01/26 06:18:30 UTC

http://www.hanggliding.org/viewtopic.php?t=28290
Report about fatal accident at Quest Air Hang Gliding
Davis Straub - 2013/02/09 05:38:41 UTC

The glider pitched up.
The glider stalled.
A standard 130 pound test weak link was being used.
The weak link broke.
So what?
http://www.hanggliding.org/viewtopic.php?t=31717
Weak link?
Davis Straub - 2014/08/20 19:48:26 UTC

Many of us are now using 200 lb test line from Cortland.
2015/01/26 06:28:38 UTC - Sink This! -- Comet
2015/01/26 07:08:06 UTC - Sink This! -- Paul Hurless
Can either of you total douchebags explain to me what your point is in thumbs-downing someone whose post consists solely of quoting one of your fellow total douchebags making blindingly obviously contradictory statements?
---
2015/01/26 17:30:00 UTC

This note originally appeared at the beginning of this post:
This is actually Tad logged in as Steve. When Tad logged in as Tad tries to post he gets this message:

http://www.kitestrings.org/posting.php?mode=reply&f=2&t=6
403 Forbidden
Forbidden
You don't have permission to access /posting.php on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
If this works and the bug or hack gets fixed I'll change the posts attribution back to what it should be.
So I (obviously) was able to submit the post logged in as Steve and a short time later - logged into the Administration Control Panel as Tad - change the attribution to Tad but I still can't post or edit posts as Tad. Having to do this as Steve. Fuckin' nuts.

Problem follows from Safari to Firefox.

Oh well, at least I have a workaround until this gets fixed. (Hope Bob has the same problem. With no power sharing / trust in any of his highly valued members he'd be majorly fucked.)
---
2015/01/26 17:55:00 UTC

Problem appears to have disappeared. Editing this as Tad. (And Steve's now an Administrator.)
Post Reply