Weak links

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

Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Jim Rooney - 2013/03/05 19:42:58 UTC

My god my head hurts.
- Fuck your god.
- How? Don't you need a few synapses firing every now and then to feel a sensation up there?
Zack C - 2013/03/05 15:16:23 UTC

Yes, this is very much about safety. What happened at Quest last month has only reinforced my position.
Wow...
So you know what happened then?
Yeah. Everyone and his fuckin' dog knows what happened on this one.
OMG... thank you for your expert accident analysis.
Versus the no analysis whatsoever from the assholes at Quest who've been perfecting aerotowing for twenty years.
You better fly down to FL and let them know.
Why? Everyone down there with a double or better digit IQ - which means Lauren's still out of the loop - knows EXACTLY what happened. If they didn't they'd be engaging in these discussions instead of going about their business like nothing happened and refusing to "SPECULATE".
I'm sure they'll be very thankful to have such a crack expert mind on the case analyzing an accident that you know nothing about.
- And I'm sure they're all scared shitless of anybody with half an ounce or more of common sense...

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

The normal braking force in pounds for a weak link is around 180, at least that is the regular weak link line used at most aerotow operations. By adding a second weak link to your bridal you are cutting the load on each link by half, meaning that the weak link will not break at the intended 180 pounds but it will need about 360.
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.
...taking any more than the most cursory of looks into what they're doing.

- When some asshole launches a glider without first connecting himself to it...
The Press - 2006/03/15

The Civil Aviation Authority (CAA) is urgently pushing for new hang-gliding industry standards after learning a hang-gliding pilot who suffered serious injuries in a crash three weeks ago had not clipped himself on to the glider.

Extreme Air tandem gliding pilot James (Jim) Rooney safely clipped his passenger into the glider before departing from the Coronet Peak launch site, near Queenstown, CAA sports and recreation manager Rex Kenny said yesterday.

However, he took off without attaching himself.

In a video, he was seen to hold on to the glider for about 50 meters before hitting power lines.

Rooney and the passenger fell about 15 meters to the ground.
...you don't need to drive down to New Zealand and wait until he comes out of his coma to know that the stupid motherfucker never does hook-in checks.
Far better data than the people that were actually there.
- So you're saying that the people who were actually there are sitting on better data than what they've publicly released? So what reasons do you think are behind their decision to suppress it, declare this an unpreventable freak accident, and carry on with business as usual?

- How much more dead would your idiot friend be if the people who were actually there were somewhere else?
In short... get fucked.
http://ozreport.com/forum/viewtopic.php?t=10
Welcome to, and policies of, the Oz Report discussion group
Davis Straub - 2003/03/04 02:07:45 UTC

Be civil or you will be banned from all of the Oz Report forum.
Unless you're sucking Davis's dick - then you can do or say anything you feel like.
All of that said, weak link breaks are rarely more than an inconvenience.
Shit in aviation that's inconvenient inevitably contributes to and causes fatalities.

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.
Twice as many launches and landings per successful mission, twice as many opportunities for the planes at both ends of the string to get killed.
But there's no sensible reason to expose ourselves to the increased risk, however small.
Grow a pair, Zack.

http://www.hanggliding.org/viewtopic.php?t=27396
Scooter tow faillure... or Never Land On Your Face
Mitch Shipley - 2012/10/22 19:04:16 UTC

We engage in a sport that has risk and that is part of the attraction.
The more stupid Quest risks we expose ourselves to the more attraction this sport holds for us.
Again, tell me how all this nonsense is about "safety"?
Broken Rooney Link, whipstall, tumble, dead asshole...

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

Do the math.
So, a stronger weaklink allows you to achieve higher AOAs...
Why are we discussing high angles of attack? I was under the impression that absolutely nothing was really understood about this freak accident. Isn't it just as likely that Zack got into trouble due to his maintaining too low an angle of attack?
...but you see high AOAs coupled with a loss of power as *the* problem?
Here's a thought...

http://www.youtube.com/watch?v=VYe3YmdIQTM


Don't use a device which couples a high angle of attack with a catastrophic and irreversible power failure as the focal point of your safe towing system.
So you want something that will allow you to achieve even higher AOAs?
- High angles of attack, to the point of stall, are virtual inevitabilities when flying hang gliders in thermal conditions - on or off tow.
- There is NOTHING in hang glider aerotowing that more effectively allows one to achieve a high angle of attack like a Rooney Link.
- Want:
-- to enhance that a bit? Take half of the tow tension off the keel, declare yourself a Pro Toad, and reroute it all to your shoulders.
-- the best of all worlds? Go pro toad with a Rooney Link in thermal conditions and count on your track record to see you through.
Are you NUTS?
Not nuts enough to wanna have anything to do with any of you stupid pigfuckers.
I'm tired of arguing with crazy.
As I said many times... there are those that listen with the intent of responding... you unfortunately are one.
I don't think even Kinsley is stupid enough to be listening to you at this point.
You've done a great job of convincing me never to tow you.
Gee Jim. Just a few years ago when you were towing people who didn't wanna be inconvenienced the way Zack Marzec was...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links
Jim Rooney - 2007/07/22 22:30:28 UTC

I've heard it a million times before from comp pilots insisting on towing with even doubled up weaklinks (some want no weaklink). I tell them the same thing I'm telling you... suck it up. You're not the only one on the line. I didn't ask to be a test pilot. I can live with your inconvenience.
...you'd just order them to go to the back of the line, slap on a Rooney Link, and suck it up. Really great to see the way your safety standards maturing at the rate they are.
Thank you for that.
And thank you for helping to remove a little more possibility of someone I've put a lot of deprogramming effort into following in the steps of your idiot buddy and getting needlessly smeared all over a runway.
Mission accomplished.
Image
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Deltaman - 2013/03/05 21:02:34 UTC
Jim Rooney - 2013/03/05 19:42:58 UTC

I'm tired of arguing with crazy.
Is that a way to say that you are intellectually beaten ?
Should we endure it much longer?
Please let me know: are you a gallinaceous, extremely aggressive and arrogant, foaming at the mouth, having undergone a lobotomy ?
http://ozreport.com/forum/viewtopic.php?t=1238
NZ accident who was the pilot?
Lauren Tjaden - 2006/02/21 20:37:39 UTC

Yes, the Jim in the article is OUR Jim, Jim Rooney. It was a tandem hang gliding accident, and it involved a power line. I have no more information about the accident itself.

Jim sustained a brain injury. He was and is heavily sedated, which means the doctors don't know and can't test for how serious the brain injury is. He is in critical but stable condition. Tommorrow (which should begin soon in NZ) the doctors will begin to reduce his medication, and they will have more information at that time.
I'd say close enough - but he was ALWAYS like this.
Jim Rooney - 2013/03/05 19:42:58 UTC

So, a stronger weaklink allows you to achieve higher AOAs... but you see high AOAs coupled with a loss of power as *the* problem? So you want something that will allow you to achieve even higher AOAs?
Take a rest. We will explain you again and again..
By taking a stronger weaklink we expect no failure crossing a turbulence, or a thermal (except to protect the glider).
Wanted to be tow off should be only managed with a reliable release for critical situations (easy to actuate, lanyard already in your hand or mouth release). I know you aren't prepare for that, just wait a decade more before to begin with...
In a high pitch and AoA situation near the ground, a weak weaklink can kill you. We had the evidence, but read others stories again if you need..
Logically, a stronger weaklink failure will kill you too.
But using a stronger weaklink let you the chance not to break it. Can you understand that ?
Damn it would be great if that finally sunk through a second or two before his brains got smeared all over the inside of his helmet.
Zack C - 2013/03/05 21:11:09 UTC
Jim Rooney - 2013/03/05 19:42:58 UTC

So you know what happened then?
I never said that. I know no more than what's been posted by Mark and Paul. But they've given a pretty thorough description of events, and as I've said from the beginning, if I was in the situation described, the last thing I'd have wanted was for the weak link to break. So yes, the incident reinforced my position.

What we do know is that Zack Marzec was climbing rapidly due to very strong lift and suffered a severe stall following a sudden loss of towline tension. As cited in my previous post, this is not the first fatality following that description.
Again, tell me how all this nonsense is about "safety"?
If you have to ask that after I post an analysis of the problem, reports of three fatalities, a personal account of what could have been a fatality with less altitude, and seven videos, I don't think I'll be convincing you of anything.
So, a stronger weaklink allows you to achieve higher AOAs...
No, and I never said anything of the sort. The problem is precisely that tension (the only thing a weak link can limit) is not a direct function of attitude. No weak link can prevent a high pitch attitude, no matter how light, and a lighter one is at a greater risk of breaking if your attitude does get high.

You've repeatedly assigned sentiments to me I never expressed, ignored my questions, and asked me questions I've already answered.
At least he's been consistent in that regard throughout his hang gliding career.
I'm beginning to wonder if you're actually reading what I'm writing.
Who cares? This is all about non Flight Park Mafia people reading what you're writing.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Kinsley Sykes - 2013/03/05 21:37:38 UTC
Zack C - 2013/03/05 21:11:09 UTC

problem is precisely that tension (the only thing a weak link can limit) is not a direct function of attitude
Then what is it a function of?
How hard the two planes are pulling on the ends of the towline. Period. Spend a couple months trying to get that concept sunk in then get back to us on your progress.
Jim Rooney - 2013/03/05 21:40:02 UTC

I'm not saying that you've claimed that a stronger weaklink allows for a greater AOA... I'm telling you that it does.
So? You're an established moron and liar. So nobody with half a brain or better really gives a rat's ass about what you're telling him.
You know this.
I'll spell it out anyway...
Save your breath. You can only get away with this crap with the typical dregs who infest this sport.
Increases in AOA increase the load factor... push it beyond what the weaklink can stand and *POP*, you're off tow.
Funny. I never had any problem with my Rooney Links popping when I was doing everything possible to keep them from popping.
Increase the load factor that the weaklink can withstand and you increase the achievable AOA.
So how come there are no charts from USHGA or in Towing Aloft correlating G rating with achievable angle of attack?
This ain't truck towing. There is no pressure limiting mechanism.
Towlines and weak links don't transmit PRESSURE - asshole.
Push out and you load the line.
So the line can't possibly be drooping both before and after you've pushed out?
Push out hard and you'll break the weaklink... that's the whole idea.
And what a GREAT IDEA!!! Just pitch out abruptly and...

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

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

You can tell me till you're blue in the face about situations where it theoretically won't let go or you can drone on and on about how "weaklinks only protect the glider" (which is BS btw)... and I can tell ya... I could give a crap, cuz just pitch out abruptly and that little piece of string doesn't have a chance in hell. Take your theory and shove it... I'm saving my a$$.
...that puppy doesn't have a chance in hell. The glider will pitch up, break the weak link, and you fly away. Instant hands free release Image
You want to break off the towline?
OF COURSE I DO!!! Why would ANYONE *EVER* wanna stay ON the towline?
Push out... push out hard... it will break.
Hell, sometimes you don't even need to do that much. Like when Zack Marzec got slammed by that thermal last month and had the bar to his knees. His Rooney Link STILL popped and increased the safety of the towing operation - for Mark Frutiger. Is there ANYTHING this remarkable piece of fishing line CAN'T do? No wonder Donnell was awarded USHGA's Presidential Citation in 1984 and NAA Safety Award in 2007.
As others have pointed out, they've used this fact intentionally to get off tow. It works.
Yeah Jim Keen-Intellect Rooney... When you're flying Industry Standard equipment with long track records it's about the only thing that does.
You want MORE.
Yeah, he's the pilot of the HANG GLIDER.
I want you to have less.
Yeah, you're the shithead driving the gas guzzler with the nice reliable engine that climbs away even faster after you've dumped and killed the guy who's paying you for the trip.
This is the fundamental disagreement.
And it ALWAYS seems that the guys who've gotten tired of being inconvenienced by being dumped and crashed by Rooney Links are pushing for heavier fishing line while the wise old motherfuckers on the front end are more concerned about increasing the safety of the towing operation and being thanked for making good decisions in the interest of other people's safety.
You're afraid of breaking off with a high AOA? Good... tow with a WEAKER weaklink... you won't be able to achieve a high AOA.
Oh! Why didn't I think of that? Come to think of it... How come:

- no tow operations are using anything lighter than 130 thirty to protect their less skilled pilots?

- Mark Knight and Mel Glantz are using the same fishing line on a piddling little Hang Two like Bryan Bowker...

http://www.youtube.com/watch?v=VYe3YmdIQTM


...that a top notch Pro Toad like Zack Marzec was using - and achieving similar results?

Don't you feel just a wee bit nervous about putting somebody up on some light fishing line that nobody's ever been stupid enough to use before that:

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Rooney - 2013/02/13 19:09:33 UTC

It was already worked out by the time I arrived.
The reason it sticks?
Trail and error.

Every now and then someone comes along with the "new" idea of a stronger weaklink. Eventually, they scare themselves with it and wind up back with one that has a very proven track record. I mean really... no exaggeration... hundreds of thousands of tows.

Say what you will, but if you want to argue with *that* much history, well, you better have one hell of an argument... which you don't.

It amuses me how many people want to be test pilots.
It amuses me even more that people...
A) Don't realize that "test pilot" is exactly what they're signing up for and B) actually testing something is a far more involved process than "I think I just try out my theory and see what happens".

Allow me to repeat... hundreds of thousands of tows.
Sure, there's other stuff out there too. Some of it even has a number of tows behind it... but hundreds of thousands is a very large number.

That's not "religion" my friend.
The shit works. It works in reality and it works consistently. It's not perfect, but Joe-Blow's pet theories have a very high bar to reach before they are given credence.
- has:

-- not been worked out by the time - or after the time - you arrived?

-- had no trail and error to make it stick?

-- no proven track record - I mean really... no exaggeration... zeros of thousands of tows?

- would require a test pilot actually testing something in a far more involved process than "I think I'll just try out your theory and see what happens"?

- might be shit that doesn't work in reality or consistently?
Problem solved.
- Not really. You haven't told us what you recommend.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Davis Straub - 2011/08/26 14:04:52 UTC

We had six weaklink breaks in a row at Zapata this year.
120? 100? 80? 60?

- Any danger of anyone running off the bottom of the FAA legal rannge? Oh, right! You motherfuckers don't do legal range - just accepted standards.

- Yeah, every time you open your shitty little mouth you blatantly contradict yourself and one or two more people are able to see what a malignant little parasite you are.
I'm sorry that you don't like that the tug pilot has the last word... but tough titties.
Don't like it?
Don't ask me to tow you.

Go troll somewhere else buddy.
I'm over this.
That was a REALLY great friend you had there Zack Marzec. Hope your short life and way shorter hang gliding career was really enriched by relationships like that.

There are gonna be more of these, Mister Jim Keen-Intellect Rooney. This Ponzi scheme of yours won't last forever and if hang gliding is to have any future history it isn't gonna remember you kindly.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Kinsley Sykes - 2013/03/05 21:48:54 UTC
Deltaman - 2013/03/05 21:02:34 UTC

Is that a way to say that you are intellectually beaten ?
Should we endure it much longer?
Please let me know: are you a gallinaceous, extremely aggressive and arrogant, foaming at the mouth, having undergone a lobotomy ?
En Anglais - try chicken instead of gallinaceous. And as for a lobotomy,try looking in the mirror.
What's he said that's wrong, that doesn't add up?
So you trade off your ultra strong weaklink...
WHAT "ultra strong" weak link? He's talking about something in the middle of the safety range - comparable to what sailplanes use in REAL aviation.
...for your infallible release?
You wouldn't have a clue what an infallible release was if it bit you in the ass. You're quite happy with Industry Standard shit so shut the fuck up about stuff that's been DESIGNED and TESTED.
Not a choice I would make.
It's not a choice I'd want you to make. We obviously need a few more assholes to get killed flying Industry Standard junk and using Rooney Links to make their decisions for them to get some more traction getting these points across.
There are plenty of videos of people getting towed with too high of an AOA - that's the problem.
That's *A* problem. And:

- a student pilot doesn't deserve to be killed by a Rooney Link because he isn't flying perfectly enough all the time on his early tows.

- I'm perfectly cool with some established asshole like Paul Hurless or Craig Hassan who "thinks" that he's so fuckin' hot that high angle of attack will never be an issue for him leaving the gene pool before he does any more damage to it.
Yes they will stall if they release...
How many people do you know who deliberately release when they're at a high angle of attack?
...the weaklink breaks...
How many people have we killed since the beginning of last month because their Rooney Links have blown when the glider was at a high angle of attack?
...the tug's engine stalls...
We don't have a whole lot of tug engine stalls on tow 'cause when that happens the results tend to look like THIS:

Image

And don't you think that it's remarkable that, even though we ALL KNOW that the more complicated a piece of equipment is the more likely it is to fail, four cylinder four-stroke 914 Rotaxes - with their carburetion, ignition, lubrication, cooling, turbocharging systems and turning over at several thousand rpms - virtually never fail while Industry Standard releases virtually never work?
It's not an equipment issue, it's a pilot issue.
You're right. Zack Marzec really had no clue what he was doing back there. His equipment was either top notch or irrelevant (I can never remember which). And if you, with your fine Lookout training and hook knife skills, had been in an identical situation you'd have suffered no more than the inconvenience of another Rooney Link pop serving its purpose of clearly protecting you from a high angle of attack - just in case you yourself weren't entirely up to the task.
It proves nothing.
You're right. Anybody who gets blasted by a monster thermal at 150 feet and can't hold his nose down deserves to die. Fuck Zack Marzec.
This has descended into pig wrestling - everyone gets dirty but only the pig is enjoying it.
What we'd really enjoy is Davis and Rooney getting killed for easily predicted and preventable reasons, saying toldyaso, and having some intelligent rational discussions to start getting some of these three decades old insane problems fixed.
You guys are all over the place to the point where I have no idea what your point is other than you don't like 130lb greenspot.
- So why don't you just go to the fallback position you took a couple of summers ago?

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...
The assholes who just helped Zack Marzec kill himself must know what they're doing 'cause they do it a lot so it's best just to keep on letting them do your thinking for you.

- Don't like the listening to the guys who are all over the place to the point at which you have no idea what their point is - other than they don't like 130 pound Greenspot? Just wait another week and the 130 pound Greenspot pin benders will shut down the discussion and it will soon thereafter drift off the front page and everything will continue on just as before.
I bow to your collective brilliance, I wish I was 10% as smart as you obviously are.. I am in awe.
Naw, just keep bowing to Lauren's collective brilliance...

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Kinsley Sykes - 2011/08/25 04:12:33 UTC

An eminently qualified tandem pilot reported a random incident that we all could learn from
My response would be - "Thanks for letting us know that we have to be careful about how long our weaklinks are".
All the other crap you (ridgerodent) wrote is just noise.
...learn from her, and ignore the people who keep warning about these deficiencies BEFORE her lot kills the next asshole.
Deltaman - 2013/03/05 21:53:04 UTC
Kinsley Sykes - 2013/03/05 21:48:54 UTC

infallible release? Not a choice I would make.
http://ozreport.com/forum/viewtopic.php?t=22660
What can be learned from this "scooter" towing accident?
Jim Rooney - 2011/02/06 18:35:13 UTC

The minute someone starts telling me about their "perfect"system, I start walking away.
lobotomy you said ?..
Deltaman - 2013/03/05 21:55:55 UTC

Real fundamental disagreement seems to be here:

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Jim Rooney - 2013/03/05 21:40:02 UTC

You're afraid of breaking off with a high AOA? Good... tow with a WEAKER weaklink... you won't be able to achieve a high AOA. Problem solved.
How weak you recommend ? cause 130lb' Zack M was still too much..
Kinsley Sykes - 2013/03/05 21:59:16 UTC

The Titanic was unsinkable - kind of like infallible...
Bullshit.

NOBODY with half a brain or better thought the Titanic was unsinkable - and the compartmentalization system wasn't all that good.

The Titanic was NOT designed to plow into or scrape alongside icebergs. So it would've been a good idea to slow the fuck down when they got warnings of ice fields ahead.

Likewise a hang glider is NOT designed to be flown:

- from the:
-- downtubes with both hands
-- the basetube with one hand

- into a runway nose down

- with one wing in the branches

- into a dust devil at low altitude

- on tow with any expectation of a lot of roll stability

- with the expectation that everything's gonna be just ducky if towline tension is abruptly subtracted from the equation when it's being blasted up by a monster thermal

But hey... You're just happy as a lark swallowing the Flight Park Mafia line that...

http://groups.yahoo.com/group/TUGS/message/1149
[TUGS] aerotow instruction was Re: Tug Rates
Tracy Tillman - 2011/02/10 20:08:32 UTC

Hey Tad.

Anybody who is truly a good pilot, in any form of aviation, knows that the knowledge, skills, and judgement you have in your head, learned from thorough instruction from a good instructor with a good curriculum, are the best pieces of equipment you can fly with. Good equipment is important, the best equipment is a well-trained brain.
...you can go up with any crap anybody sells you, never bother looking into any technology anybody outside of the mainstream has busted his ass to develop and provide, slap on a Rooney Link with the expectation that it break as early as possible in a lockout situation but be strong and reliable enough to avoid frequent breaks from turbulence, and look forward to a long and trouble free towing career - barring, of course, any freak accident that nobody's permitted to speculate about.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Swift - 2013/03/05 22:28:20 UTC
Kinsley Sykes - 2013/03/05 21:59:16 UTC

The Titanic was unsinkable - kind of like infallible...
Oh! Sarcasm, which usually doesn't work with those that speak your own language so use it on someone that doesn't.
I think I understand what you mean.
1. We expect the release to not work.
2. We don't expect you to be able to use the release, even if it did work.
3. We don't design the weaklink to actually protect from overloading the glider.
4. We design the weaklink to make up for 1 and 2.

How many Ocean Liners advertise their ship is guaranteed to sink but they have a great backup system of row boats and paddles?
Freedomspyder - 2013/03/05 22:44:36 UTC
Jim Rooney - 2013/03/05 21:40:02 UTC

Push out hard and you'll break the weaklink... that's the whole idea.
I see the difference in whether it was the pilot pushing, or whether it was just a big fat thermal. The one the pilot could have released, the other the pilot had no choice.
Aerotowed hang glider pilots are too stupid to be allowed any choices. Why do you think God gave us Bobby Fucking-Genius Bailey and Jim Keen-Intellect Rooney?
Mike Lake - 2013/03/05 23:05:17 UTC

So, Zack offers a polite, well constructed argument about weak-links in a thread about weak-links and gets accused of trolling.
Well done, Zack, I've found your posts to be very clear and credible.

Accusations of trolling, Fuckoff requests? I'm sure the credibility of some others must have shifted a full two places.
Jim Rooney - 2013/03/06 01:42:41 UTC

Oh god, I've been offensive to people that I hold in contempt.
How will I ever sleep at night?
Hopefully so soundly that you'll suffocate on your own vomit.
Mike Lake - 2013/03/06 02:28:00 UTC

...make that a full three places.
Zack C - 2013/03/06 04:22:08 UTC
Davis Straub - 2013/02/15 02:04:29 UTC

I can't imagine anyone arguing that they would.
http://ozreport.com/forum/viewtopic.php?p=118059#118059
Zach Marzec
Jim Rooney - 2013/03/05 21:40:02 UTC

...tow with a WEAKER weaklink... you won't be able to achieve a high AOA.
Still having trouble imagining, Davis?
Davis was NEVER having any trouble imagining. NOBODY who uses 130 pound Greenspot or one G as a good rule of thumb is using a weak link for anything BUT preventing attitudes that could be catastrophic near the ground.
The videos referenced above illustrated dangerous roll attitudes achievable before a weak link break. Pitch is no different. Just as with roll, yes, you will eventually break the weak link if you pitch away from the tow line, but there's nothing stopping your attitude from becoming dangerous before that happens.
In what are we gonna put our trust? Our eyes, experiences, and common sense? Or the opinion of Jim Keen-Intellect Rooney?
If you doubt this, Jim, try this experiment. Tow up, get upright in flare position, and aggressively flare the glider. See how high you can get the nose before the weak link breaks. Better yet, get high on the tug intentionally and then stuff the bar (creating a slack line) before doing this. You can stop pushing out as soon as the weak link breaks, which if you're right should happen before your angle of attack gets too high.
Better even yet - do this at a hundred and fifty feet.
For a somewhat milder example, this video (again) demonstrates how well a standard weak link keeps the glider from having a high angle of attack.

0:50
http://www.youtube.com/watch?v=JR_4jKLqrus
Jim Rooney - 2013/03/05 21:40:02 UTC

You want to break off the towline? Push out... push out hard... it will break.
As others have pointed out, they've used this fact intentionally to get off tow. It works.
I'd like to see someone do this in a lockout near the ground.
Not just SOMEONE - let's go for Rooney, Ryan, Sam, and/or Jack.
Jim Rooney - 2013/03/05 21:40:02 UTC

Increase the load factor that the weaklink can withstand and you increase the achievable AOA.
The weak link limits line tension, not load factor. Given only line tension, load factor, or angle of attack, you cannot make any assumptions about the others. A glider being pulled by a super-slow tug just above the glider's stall speed with both aircraft flying level will be at a load of 1 g despite the glider's high angle of attack. If said tug were to increase its power and it and the glider fly faster to continue flying level, the glider's load will continue to be 1 g despite the lower angle of attack and higher line tension.
Jim Rooney - 2013/03/05 21:40:02 UTC

I'm sorry that you don't like that the tug pilot has the last word...
I never said that. Tug pilots can choose who they tow just as glider pilots can choose who tows them. I'm fine with that. I'm not trying to convince you to tow me.
It sickened me every time I was stupid enough to hook up behind that motherfucker - along with all the 130 pound Greenspot assholes who trained and signed him off.
Zack C - 2013/03/06 04:25:17 UTC
Kinsley Sykes - 2013/03/05 21:37:38 UTC

Then what is it a function of?
Tug speed, glider pilot mass, glider type, turbulence, glider position, glider alignment...more things than I comprehend. What I do know is that a glider can be at any attitude with any line tension. Just imagine a glider upside down with a slack line - still attached to the line.
Bill Bryden - 2000/02

Dennis Pagen informed me several years ago about an aerotow lockout that he experienced. One moment he was correcting a bit of alignment with the tug and the next moment he was nearly upside down. He was stunned at the rapidity. I have heard similar stories from two other aerotow pilots.
Zack C - 2013/03/06 04:29:13 UTC
Brad Gryder - 2013/03/06 03:33:45 UTC

I own my own tug and I do decide what weak link strength I use.
What I meant was that you are limited in your choice because you cannot choose a weak link stronger than the tow mast - it places an upper limit on your weak link value. That upper limit is rather low (about four strands of 130 from what I understand, requiring three strands to keep the mast from breaking, which is less than what tandems generally use). This is what I don't like about the built-in weak link.

With our trike, we are free to choose whatever tug weak link value we like.
What do you do about your unwise and ignorant tow operators who might not use a weak link on the tug's end?
Zack C - 2013/03/06 04:36:09 UTC
Davis Straub - 2013/03/05 15:42:52 UTC

I love these private videos.
The content or the fact that they're private? Are they a problem?

I have hundreds of videos. The vast majority are private because I don't want the better ones with more general appeal to be lost in the noise.
Zack C - 2013/03/06 14:25:39 UTC
Kinsley Sykes - 2013/03/05 21:48:54 UTC

You guys are all over the place to the point where I have no idea what your point is other than you don't like 130lb greenspot.
In short, we should be thinking about weak links the same way the sailplane guys do.

Stick to a weak link around 1.4 times your glider's MCOW. Stop thinking of weak links as releases, lockout protectors, and pitch limiters.
Jim Gaar - 2013/03/06 18:17:15 UTC

I believe that's what I said already eh!
Zack C - 2013/03/06 14:25:39 UTC

Stick to a weak link around 1.4 times your glider's MCOW. Stop thinking of weak links as releases, lockout protectors, and pitch limiters.
Just not like you wrote it...

I don't believe this is anything but common knowledge to the tug pilots I know and "most" pilots as well.
Fuck you. Because of that fucking tow mast breakaway ALL Dragonfly jockeys are using weak links as releases, lockout protectors, and pitch limiters.
Davis Straub - 2013/03/06 18:29:05 UTC

You know, after all this discussion I'm now convinced that it is a very good idea to treat the weaklink as a release, that that is exactly what we do when we have a weaklink on one side of a pro tow bridle.
Yeah Davis, what with the hundreds of copies of your useless and inaccessible bent pin mini barrel pieces of shit it would probably be a good idea for you to continue to risk your useless life on Marzec Links too. To do otherwise would sure as hell open you up to a lot of liability issues - in addition, of course, to revealing to everyone what...

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.
...total asses you and Bobby are.
That that is exactly what has happened to me in a number of situations and that the whole business about a weaklink only for the glider not breaking isn't really the case nor a good idea for hang gliding.
Really Davis?

http://ozreport.com/9.032
The Worlds - weaklinks
Davis Straub - 2005/02/07

So if weaklinks don't do much to save us from lockouts, an argument heard repeatedly at the Worlds, then why are we using them after Robin's lockout (and not before)?

What exactly is the point of weaklinks? Why should we be using them? What is the tradeoff in safety between breaking a weaklink and thereby having a problem, and not breaking a weaklink and thereby having a problem?

Perhaps if you laid out the case re the tradeoffs involving weaklinks, we could make a better decision about them. For a couple of years I have flown with a doubled weaklink because, flying with a rigid wing glider, I have found that there is little reason to expect trouble on tow, except from a weaklink break. Am I wrong in this?
Why don't you tell us about some of those situations in which your Davis Link blew at just the right time to bail your ass out.
I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
I'm happy to have you on the same weak link that just inconvenienced to death somebody thirty pounds lighter than you too. It gives me hope.
I'm thinking about doing a bit more testing as there seemed to be some disagreement around here about what the average breaking strength of a loop of Greenspot (or orange) weaklink was.
Yeah Davis, you Steve Kroop, Bob Lane, and Rhett Radford go back to your tree and continue hanging and bouncing yourselves so we can get good really good information and end these disagreements about these pieces of fishing line people have pulled out of their asses and proclaimed to be accepted one-size-fits-all standards.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Davis Straub - 2013/03/06 18:35:42 UTC

http://ozreport.com/9.049#1
http://ozreport.com/9.050#7
Tormod Helgesen - 2013/03/06 18:41:15 UTC

Why is this even discussed as an equipment issue when it's a pilot issue? Don't tow if you can't hack it.
I can hack towing just fine - motherfucker - just as long as I don't have some Bill/Bobby/Bo/Rooney caliber shithead looking out for my safety and pissing all over the FAA aerotowing safety regulations.
Swift - 2013/03/06 19:27:59 UTC
Tormod Helgesen - 2013/03/06 18:41:15 UTC

Why is this even discussed as an equipment issue when it's a pilot issue?
A dumbed down weaklink is now the new improved release.
Don't tow if you can't hack it.
One should at least be able to do one handed pushups before even thinking about aerotowing.
Zack C - 2013/03/06 21:37:38 UTC
Davis Straub - 2013/03/06 18:29:05 UTC

That that is exactly what has happened to me in a number of situations...
Besides getting dragged, can you describe these situations, or any other situations in which you would treat a weak link as a release?

(I should note that in the case of a bridle wrapping on the tow ring, a weak link on the other end of the bridle can act desirably as an automatic release, but this is not a reason to use weaker weak links (I'll elaborate on why if anyone desires).)
I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
I never had a serious problem with it either. But I've seen enough evidence that I'm not going to wait until I do.
Davis Straub - 2013/03/06 21:48:38 UTC

I've already described them here.
Bullshit.
Brad Gryder - 2013/03/06 22:17:31 UTC

In my opinion, because we hang glider pilots are more exposed, have little crash protection, and can land almost anywhere in an emergency, then we would be better served to be near or below the lower end of the suggested weaklink strength spectrum.

Any hang glider pilot who is fearful of having a weak link failure anytime during tow is in need of additional training. He's either towing over areas where he shouldn't be, or he's flying wrong, or both.
Or he has enough brains to know that US aerotowing is pretty much totally controlled by a bunch of corrupt, incompetent, single digit IQ, serial killing pigfuckers whose main talents lie in blaming the dead guys for making no effort to actuate their Wallaby-style releases or pull in following Rooney Link disintegration and not speculating.
I'd rather have my weak link serve a dual function (as both a safety fuse and as an emergency back-up release)...
And I'd rather have my weak link pull my glider off the car and stuff all my battens - but that ain't gonna happen neither.
...than to be so strong that it continues to pull me into the ground should I impact while on tow.
I'm envisioning that and looking for the downside. I got nuthin'. How 'bout you?
A good well-practiced aerotow pilot can manage his line tension and keep it reasonably low, then break the weak link to come off tow if he wishes to do so.
And reattach himself if he changes his mind.
When the hang glider pilot breaks a "weak" weak link, the tug pilot just feels a little nudge, and that's it.
Regardless of what angle the glider is pulling that two hundred plus pounds of illegally light tension.
Nothing scary happens on either end of the line, and both pilots fly away as normal.
Unless you count what happened to Mike Haas, Steve Elliot, Roy Messing, Lois Preston, and Zack Marzec on the back end of the line and Dick Reynolds and Frank Murphy on the front as scary and a bit odd.

Hang Glider Lock-Out!
http://www.youtube.com/watch?v=fnrh9-pOiq4
MorphFX - 2011/03/20
A hang glider pilot learning to aerotow starts a mild PIO that leads into a lock-out.
dead
02-00319
http://farm8.staticflickr.com/7523/15601000807_705ab49977_o.png
Image
Image
http://farm6.staticflickr.com/5606/15600335029_3c234e6828_o.png
14-03708
http://www.kitestrings.org/post6995.html#p6995

What a load of pure unadulterated crap.
Davis Straub - 2013/03/06 22:21:00 UTC

I'm with you, Brad.
Why am I not the least bit surprised?
Swift - 2013/03/06 22:45:37 UTC
Brad Gryder - 2013/03/06 22:17:31 UTC

When the hang glider pilot breaks a "weak" weak link, the tug pilot just feels a little nudge, and that's it. Nothing scary happens on either end of the line, and both pilots fly away as normal.
Both pilots fly away as normal if normal includes the occasional stall/tumble.
A good well-practiced aerotow pilot can manage his line tension and keep it reasonably low,
Zack Marzec was a good well-practiced pilot.
"WAS" being the operative word here.
then break the weak link to come off tow if he wishes to do so.
If he wishes to do so... Therein lies the problem.
I'd rather have my weak link serve a dual function (as both a safety fuse and as an emergency back-up release), than to be so strong that it continues to pull me into the ground should I impact while on tow.

Any hang glider pilot who is fearful of having a weak link failure anytime during tow is in need of additional training. He's either towing over areas where he shouldn't be, or he's flying wrong, or both.
The choice to get off tow should be with the pilot. Not a cheap piece of string.
If you hit the ground right off the cart, you are doing it wrong.
And I don't really give a shit what happens to you - Peter.
Then, your admonishment above kicks in.
And the field is cleared for people who CAN walk and chew gum.
If you hit the ground without wheels, in any event, I imagine a 600 pound weaklink would break just about as fast as weak 130 pound Greenspot.
If you:

- hit the ground without wheels in the course of a routine free flight landing you can kill yourself

- are being:
-- two point aerotow launched on a Rooney Link and you hit the ground without wheels you can kill yourself plus 226 pounds of thrust
-- one point aerotow launched on a Rooney Link and you hit the ground without wheels you can kill yourself plus 260 pounds of thrust

- decide to aerotow launch minus wheels and without taking advantage of any of the technology that's been developed to allow you to abort before a weak link can kick in and can't manage not to hit the runway you can go fuck yourself.
Brad Gryder - 2013/03/07 01:42:14 UTC

Here's a rule-of-thumb we should tell all new aerotow pilots:

Hang Gliding Safety Tip regarding their Aerotow weak link:
"If you can't make it break, you're a flying mistake."
- Here's another idiot "rule of thumb" posted by some other aerotow operation asshole:
Quest Air

A good rule of thumb for the optimum strength is one G, or in other words, equal to the total wing load of the glider. Most flight parks use 130 lb. braided Dacron line, so that one loop (which is the equivalent to two strands) is about 260 lb. strong - about the average wing load of a single pilot on a typical glider.
- Whenever you hear somebody talking about "rules of thumb" in aviation you can be dead certain you're listening to a total moron.

- So how come this is just a rule of thumb for NEW aerotow pilots? Do the equations change for when they get older?

- Give me a three G weak link, a cooperative tug driver, and enough air and I can make it break. So what's that gonna prove?
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Davis Straub - 2013/03/07 14:05:23 UTC

Yah...
There's an "e" in that word - idiot. Take one of them out of "carabineer" and put it there.
...we were discussing this the other evening at Quest Air after dinner at the Out of Control Bar. The hang glider pilot is quite capable of putting the tug pilot in danger by climbing up and up until the tug pilot has no control as his tail keeps being pulled up.
Why does something that simple and basic need to be discussed by anyone who's been associated with aerotowing beyond the first five minutes of ground school, let alone you assholes who've been perfecting aerotowing for twenty years?
The 130 lbs Greenspot loop won't break under this scenario, nor will the three strands on the tug. The tug pilot has to recognize what's going on and release the hang glider pilot.
In other words, a weak link - ANY weak link capable of getting a glider airborne - is just as useless protecting the tug from control/crash issues as it is the glider. And an ACTUAL PILOT making ACTUAL DECISIONS executed with an ACTUAL RELEASE is the name of the game. So it's just like it is for the glider - with the exceptions that the tug driver doesn't give the glider the option of using an ACTUAL WEAK LINK and an ACTUAL RELEASE.
You don't want this to happen low and this can indeed happen right as the hang glider pilot comes off the cart and zooms up.
And yet we've NEVER had an incident in which a tug was nosed into the ground.

Reasons...

- Even a clueless glider that rockets way the fuck up - even way the fuck up enough to lock himself out and crash...

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


...or kill himself isn't really even an annoyance to the tug.

- The tug has a built in release that he can actually USE and will actually WORK in an emergency situation - instantly and without control compromise.

But I'm sure all of you useless goddam shits were too drunk by the time you finished brainstorming about the safety of the tug to get around to anything related to the safety of the glider - like the one Zack Marzec was flying at Quest until the beginning of last month.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Zack C - 2013/03/08 00:19:06 UTC
Brad Gryder - 2013/03/07 04:50:50 UTC

The towline energy can be roughly said to be towline force times decel distance prior to weaklink rupture.
How often does tension itself factor into the severity of an impact? Kinetic energy is a function of velocity and (to a lesser extent) mass. Sailplanes have more of both.
And:

- how often are we having impacts WHILE the glider's ON tow versus BECAUSE the glider is popped OFF tow?

- for what reasons are gliders having impacts on tow?

- if we're so fucking worried about gliders impacting right after coming off the cart then why the hell are we discussing the best weak link to crash with rather than the best wheels to make one of these a nonevent?

Jim Keen-Intellect Rooney says:
My general rule is "no funky shit".
but the funkiest shit out there - the shit most likely to get one's freakin' neck broken - is a basetube minus wheels. But as rabid as all the Rooney Linkers are about 130 pound Greenspot to increase the safety of the towing operation, none of them seems to have the SLIGHTEST concern about the issue that's most likely to make a critical difference on any given flight - tow or free.
Because landing out, turning-back-to-field, number of safe landing spots within glide, etc. are quite different between the hg and the sailplane, the sailplane pilot can justify using a higher weaklink strength factor than his hg counterpart.
I've never been in a tow situation where I couldn't land in the field I launched from if I lost the line at any point. Sailplanes have much better glide ratios than hang gliders so I'd imagine that would be even more the case for them. I spoke with a sailplane pilot whose training included unexpected releases at low altitude. Contrast that with our HG aerotow rating requirements, which include premature separation training only at altitude.
I totally screwed up when I read that one.

http://www.kitestrings.org/post3946.html#p3946

Thought he was saying that a hang glider with a heavier weak link was more likely to got towed out of range of the airport than one with a Rooney Link that blows at ten feet half the time.

One other point on this...

Notice that when you're advocating wheel landings for hang gliders - including XC - and pointing out that sailplanes seem to do just fine without perfecting their foot landings the argument is always that because of their speed and performance they have much better bags of field options.

But when we're advocating weak links which protect the glider from overloading over Rooney Links which increase the safety of the towing operation by making the pilots' decisions for them, the argument becomes that sailplanes are forced to fly the more dangerous weak links because the landing prospects are WORSE.
I think someone on one of the threads was referring to the FAA's range being between 80% to 200% of the maximum gross weight...
That would be me. My confusion stemmed from your use of the word 'suggested' (as the range is a requirement).
But, hell, this is hang gliding - and name anything in hang gliding that has more teeth than a guideline, recommendation, suggestion, or opinion.
But if the weak link breaks sooner verses later, the pilot is hopefully in a better position with less energy stored in his wing and barrel...
In the situations I was referencing - with the glider having a high pitch attitude and angle of attack - a weak link break at any time is dangerous.
First, I'd like to say that this pilot did a very poor job during that flight. I hope you agree.
Yes, but that wasn't my point. All that matters for the purpose of this discussion is the position and attitude of the glider at the moment of the weak link break, regardless of how he got there.
Yeah, but 99 percent of the Rooney Linkers we're always talking to are much too good to ever get into a position and attitude in which a weak link break is anything other than an inconvenience - and...

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

I can't see how the weaklink has anything to do with this accident.
...I can't see how the Davis Link had anything to do with this accident.
To answer your question, it's just dumb and potentially suicidal to force a weak link to break when you're that low and that out-of-whack...
That was my point, and why I think the idea of intentionally breaking a weak link in any situation where getting off the line is truly critical is crazy.
Hear that, Jim?

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

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

You can tell me till you're blue in the face about situations where it theoretically won't let go or you can drone on and on about how "weaklinks only protect the glider" (which is BS btw)... and I can tell ya... I could give a crap, cuz just pitch out abruptly and that little piece of string doesn't have a chance in hell. Take your theory and shove it... I'm saving my a$$.
Add Brad to the list of people who just called you and Ryan assholes. And Brad's a TUG PILOT so his opinion counts 32 times what Zack's does - and at least 128 times what Tad's does.
...but weaker would be better than strong.
In that situation, yes. But if the pilot had been a little lower, he could have been dead regardless of what weak link
...and, for that matter, release...
...he used. Had he been using a stronger weak link, it probably wouldn't have made much of a difference (at the rate he was diverging from the tow line, tension was increasing very quickly). With a little more altitude, it surely wouldn't have made a difference.

Regardless of the weak link, the best outcome would have been from releasing before getting into that situation. Not doing so was nearly fatal.
The best outcome would have been from understanding the difference between an aero and a truck tow before getting onto the cart.
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Tad Eareckson
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Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Zack C - 2013/03/08 00:35:41 UTC
Jim Rooney - 2013/03/07 06:40:02 UTC

The "purpose" of a weaklink is to improve the safety of the system.
PERIOD
If you think a glider is always safer off tow than on tow, then yes, a weak link break can only improve the safety of any situation. If you don't, and I'm still not sure what your position on that is...
Jim Rooney - 2005/09/22 14:06:27 UTC

But don't tell us that being off tow at the wrong time is all sweet and wonderful. Yes, we prepare for it, but that doesn't make it a safe situation.
http://www.chgpa.org/forums/viewtopic.php?p=4411#p4411
$15 pacifiers

...the weak link has the potential to decrease the safety of the system.
Is it perfect? No, of course not.
Not only is it not perfect, it does a really lousy job of that purpose in my book. The only thing I expect my weak link to do is keep the tow force from overloading the equipment. It does an excellent job of that. I rely on my release to get me off tow when I want and no sooner without compromising control. It does an excellent job of that.
Does it "prevent" lockouts... of course not.
So it doesn't prevent lockouts, but it does prevent excessive angles of attack?
Your glider is capable of amazing feats of strength... it is in no danger of folding up on you.
But I thought
The forces of an aerotow can get high enough to tear the wings off the glider.
http://ozreport.com/forum/viewtopic.php?p=101312#101312
Is this a joke ?
So... if it's *only* purpose is to prevent your glider from breaking apart[...]why then do we have them at all?
I know what ~600 lbs of line tension feels like. It's unsettling. I don't know what the maximum my wing can take is, but I'm not interested in finding out. Using a weak link to prevent overloading doesn't mean you have to allow tension to get as close to overloading as possible. I'm well above anything I'd ever encounter in any normal situation, which is good enough for me.

Furthermore, as I've said before, weak links cannot limit load factor. You can overload a glider in free flight - no line tension required. The load on a wing doubles just with a 60 degree bank. Thus, it would be wise to have a tension limiter that will break well below whatever tension would break your wing in unaccelerated flight.

Also, when the tension limit is exceeded, you want the rope to end up with the tug, so it's important that the rope is severed at the glider. Weak links provide a controlled means of doing this.

Weak links also provide a controlled means of keeping something less desirable from breaking. For example, with no weak link, the carabiner connecting a keel release to the glider might break, which subsequently might fail to clear the tow ring.

Perhaps most importantly, the 'equipment' weak links protect is not limited to the aircraft. Most likely your release will either break or fail to be actuatable well before the aircraft is at risk. Weak links can ensure the release never sees more tension than it's been designed and tested to handle.
For the rare individual who flies with a release that's actually been designed and tested (read: homemade).
Finally, there's the matter of weak links being required by law.
It will tear the towmast off the tug before it breaks.
Well, yeah...the tow mast was designed to be a weak link.
Is the *purpose* of my tow release "lockout prevention"?
No.
But I'll be damned if I won't use it to do so.
See... same thing.
A release terminates the tow at the pilot's decision. A weak link terminates the tow when a pre-defined line tension is exceeded. Only one can prevent a lockout with any consistency. I hardly see that as the same.

If you want to use a weak link as lockout protection, whether due to a malfunctioning or inaccessible release or failure to use your release, that's fine...but as I've explained before, don't expect it to be better at that than a stronger weak link.
Jim Rooney - 2013/03/08 02:29:51 UTC
The only thing I expect my weak link to do is keep the tow force from overloading the equipment.
And thus, we have the heart of the disagreement.
If we base the discussion on logic, physics, data... there is no disagreement. It's only when we make the mistake of permitting scummy little tug driving shits and their brown-nosers into the discussions that things start going south.
Those that believe this can go right on believing it.

Have fun with that.
I couldn't care less.

But by all means... let's keep flogging this one... I don't think it's dead enough yet.
See?
Davis Straub - 2013/03/08 02:37:02 UTC

I'm certainly with Jim on this. I appreciate the weaklink breaking under much less force.
Big surprise. What was I just saying about making the mistake of permitting scummy little tug driving shits and their brown nosers into the discussions?
Freedomspyder - 2013/03/08 03:07:57 UTC

Davis, Why did you move to the 200 pound weaklink? Was it just to stay on tow a bit more often than with the 130 pound, or for other reasons?
http://ozreport.com/9.032
The Worlds - weaklinks
Davis Straub - 2005/02/07

For a couple of years I have flown with a doubled weaklink because, flying with a rigid wing glider, I have found that there is little reason to expect trouble on tow, except from a weaklink break.
Davis Straub - 2013/03/08 03:16:54 UTC

Just cause we were breaking them apparently a little too easily at Zapata...
Oh...

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Davis Straub - 2011/08/26 14:04:52 UTC

We had six weaklink breaks in a row at Zapata this year.
A LITTLE too easily. Four or five out of six would be about right, three out of six would really be pushing the envelope.

Lemme tell ya sumpin', dickhead... In REAL aviation, aviation NOT controlled by dickheads like Russell, Paul, Lauren, Trisa, Rooney, and you...
Dr. Trisa Tilletti - 2012/06

You and I have flown sailplanes for almost as long as we have flown hang gliders. We own two sailplanes and have two airplanes that we use for towing full-size sailplanes. In all the time that we have flown and towed sailplanes, we have not experienced or even seen a sailplane weak link break.

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.
...weak links:

- are:

-- used to...
Tost Flugzeuggerätebau

Weak links protect your aircraft against overloading.
...protect the aircraft against overloading

-- rated in terms of kiloNewtons, pounds, Gs rather than strands of fishing line, magic knots, and opinions

- don't ever break
...which is actually hard to understand...
For some asshole with total shit for brains like Russell, Paul, Lauren, Trisa, Rooney, and you? Yeah.
...since the conditions are always pretty mild there, but the last one broke right off launch.
No...

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


...shit. Must've been pretty badly locked out and in imminent danger of...
Jim Rooney - 2011/08/26 02:44:10 UTC

The forces of an aerotow can get high enough to tear the wings off the glider.
This is no exaggeration... it can be done.
...getting its wings torn off, huh? Good thing he was able to level out and land OK.
I just haven't changed it.
Well you make sure you swap it out for a proper Davis Link ASAP. I really worry a lot about you and your Davis Mini Barrel and Bridle coming off the cart and getting into conditions less mild than the ones at Zapata.
I'll be checking them out more.
Thank GOD hang gliding has people like you doing the grunt work for the benefit of us all. Hard to imagine what the sport would look like without it.
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Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Weak links

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Freedomspyder - 2013/03/08 03:32:35 UTC
Davis Straub - 2013/03/08 03:16:54 UTC

...but the last one broke right off launch.
Thanks. This is my big concern. These breaks right off launch that is.
Really? My big concerns are:
- getting slammed by a monster thermal at 150 feet, having a Davis Link pop before I get stabilized, and whipstalling back into the runway
- towing operations in which people are negligent and stupid enough to tow with Davis Links which blow right off launch
- fucking dickhead Bobby Bailey's goddam tow mast breakaway
I'm glad to see pilots going to higher strengths.
I won't be happy until I see gliders going to a bit higher than the middle of the legal range with the tugs safely/legally above it.
From what I have read, the weaklink would have to be silly strong to cause a breakup of the glider.
I would predict that it would be virtually impossible to break a glider on tow behind a Dragonfly - regardless of how heavy the weak links were.
I hope no one convinces you to go back down to the 130.
He's already made the decision to do so because he's done the math and determined that he'd rather take a chance on dying the way Zack Marzec did than admit that the illegal Davis Link policies he's been shoving down everyone's throats for the past dozen years or so have directly crashed a lot of gliders and have contributed to a lot of injuries and a few deaths.

And I am SO HAPPY that he's going back to 130 because EVERY TIME HE LAUNCHES INTO THERMAL CONDITIONS there's a chance that he's gonna whipstall back into the runway. And there's not anything much better that could happen to the sport of hang gliding.
William Olive - 2013/03/08 04:13:21 UTC

And on the other hand, we were using greenspot at the Worlds in Forbes in conditions that were anything but mild, and I don't recall an inordinate number of weaklink breaks there.
ONE weak link break is an inordinate number - you dumb motherfucker. That's probably the number of breaks Quest had on 2013/02/02 and it got somebody killed.
Davis was the meet head, so he would have a better idea than I have on that.
That son of a bitch has never had a better idea about anything in the course of his entire vile existence.
Tormod Helgesen - 2013/03/08 05:40:04 UTC

Nearly 1500 tows without serious mishaps, none due to weaklinks, done in 10 very rowdy days during the worlds, all with 130lbs greenspot and pro-tow! This fact makes me stick to the 130lbs weaklink.
Good. And I hope the fact that there have been untold tens of thousands of launches from the Henson ramp sans hook-in checks with no unhooked launches makes you stick to skipping hook-in checks - for precisely the same reason.
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