Weak link question

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Tad Eareckson
Posts: 304
Joined: Wed Feb 09, 2005 8:50 am

Post by Tad Eareckson »

Gary,

Yeah, that response probably seemed overly postal but I was trying to compensate for the many times in the past when I haven't gone anywhere near postal enough. That bridge burning was long overdue.

You've got your criteria for people for whom you have and lack respect and I've got mine.

There are quite a few apologies owed in this thread and earlier ones on this topic but right now I feel pretty comfortable saying that I'm way in the clear.

But if I happen to see some blinding light down the road I'll let you and everyone else know immediately - whether or not it does any good with anyone. But don't hold your breath.

Brian,

The problem is that whenever Cragin enters an intellectual discussion it immediately ceases to be intellectual.

History time...

The problem with hang gliding is that - decades after the bamboo era - we're still trying to reinvent a couple of wheels. Hang gliders are sailplane/sailboat hybrids and we've wasted a lot of time and lives adapting they're technologies and practices.

I recall several conversations with Les King (Sport Flight in Gaithersburg, USHGA Regional Director) in the early Eighties.

In one he related how we had gone to the sailplane community for help and guidance but that they viewed our primitive five to one contraptions with contempt and told us to go fuck ourselves.

Hang gliders were first hooked up to tow lines in an intuitive manner - to the three points of the control frame corners. We used to be able to get off twenty-five or thirty tows before we'd kill someone with that configuration. Not bad.

Then a physicist stepped back, looked at the situation, reconfigured, experimented, verified, and said "Hey folks, you're doing this wrong." He, of course, was treated in a manner not dissimilar to the way I'm being treated now - and Les was significant in the implementation of that treatment.

The essence of what Donnell Hewett did was so simple. Basically - connect the tow line to the heavy part. Just like conventional gliders had been doing well before anybody bolted an engine to one and acheived sustained powered flight.

Donnell Hewett eventually prevailed and Les apologized (to me, at least).

Along with the center of mass concept Donnell established the Skyting Criteria:

http://www.birrendesign.com/rhgpa_criteria.html

which outlined guidelines for conducting safe towing operations.

(Frank got killed because at least two - including the first - of them were violated. Bill and Mike died because two others - not including the aforementioned - didn't come up to snuff.)

When these Criteria were written the towing was all ground based and a lot of the equipment, techniques, and releases sucked. (And when aerotowing first appeared the trikes were too fast and the gliders were too slow.)

The ground based towing also tended to be tension controlled and that mode of operation tends to make weak links pretty much irrelevant.

>
07: Infallible Weak Link

The system must include a weak link which will infallibly and automatically release the glider from tow whenever the tow line tension exceeds the limit for safe operation. (There is always the possibility something unexpected can happen. Breaking point should be appropriate for the weight and experience of the pilot, not to exceed 1G - sum of all towed parts.)
<

One problem in Dr. Hewett's thinking - then, and to a lesser extent, now - I respectfully maintain, is that it is impossible to define - "the" limit for safe operation - because, as he himself has said:

>
It is impossible to design a weaklink to release the pilot when he loses flight control because there is no correlation between towline tension and flight control. (A pilot may be in perfect control under high tension but out of control under low tension.)
<

And thus it is useless to try to scale the weak link to pilot experience. In any case - NOBODY does this. (What we do do (doodoo?) is fly small pilots at high G ratings and big ones at low.)

Two other related problems are the absence of a definition of a lower limit. This absence is based on an assumption that it's always better to be off tow than on and that a weak link can substitute for a release. Both of these - contrary to popular perception - are WRONG.

So all you can do is dial the weak link strength to a point high enough to keep you connected in a situation in which losing the tow would be dangerous (yeah - those situations DO exist) but low enough to keep the tension from getting ridiculous.

We don't need to calculate those numbers - the FAA had done it for us long before hang gliders were as much as a gleam in the eyes of Francis and Gertrude Rogollo.

A couple of months ago - in a context similar to the one at hand - you suggested that I might be an idiot. I didn't respond to that online but my reaction was, "OK, fair enough, what the hell, nobody's perfect."

You and I don't insult each other. We discuss and debate until one of us concedes.

I didn't go postal because of Cragins stupid insults (although - yeah - that helped). I've been insulted (and worse - misquoted and misrepresented) lotsa times in this thread before without going postal.

I went postal primarily 'cause he's helping to keep aerotowing DANGEROUS - as well as stupidly inefficient.

He reads Pages 59 and 60 of Towing Aloft, locks on like a barnacle to all the stuff they got backwards, and ignores the small fraction they got right which is consistent what I'm saying.

His mode of operation is to be more concerned with who's saying something than what's being said. Dennis - good! Tad - bad!!.

Then, paying no respect to the points Danny tried to make, follows his usual practice of waltzing into the middle of a conversation he has neither the interest nor capability of following, making one or two arrogant smug cracks, and then waltzing back out without ever bothering to address anything of substance.

Two summers ago I stated on this forum that Dr. Hewett got it backwards with respect to AT versus ground based weak links. He has conceded that point. That has given me a valuable tool to improve the safety of this aspect of the sport.

In addition to identifying dangerous equipment it's also important to identify dangerous individuals. So I stand by every word of my previous post. History is gonna prove me right on both counts.

If you've got any doubts about the trend...

Go back and compare/contrast the vicious reaction I got when I committed heresy and contended that Karen and I should not be flying the same weak link with the general tone now. We don't need Cragin or any other one size fits allers in this conversation.

>
If your position is logically correct, people will come around so long as you don't oversell or insult.
<

This is not MY position. This is what we're SUPPOSED to be doing. Just like hook-in checks. It's on the books. We just choose to ignore it. Just like hook-in checks.

As for logic... Everybody and his dog is still mass producing curved pin releases. You KNOW what the consequences of that are. Logic hasn't got a prayer. It's gonna take something more.
brianvh
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Location: manhattan, New York

Re: Weak link question

Post by brianvh »

Yes, it will take something else. But the approach you always slide into is not it. I think Matthew pointed out what needed to be done. But if you write articles nobody will listen unless you write with some humility.

BTW, a highly experienced source who wishes to stay anonymous (call him "Deepfloat") because he doesn't want to get entangled in the name calling (we're all tired of it), has a very interesting point to make.

Deepfloat says the reason 3 strings are used on the tug end instead of 4 is because experience has shown that a 4 strand breaking strength causes damage to equipment, the tug being a far more complex mechanism than a glider. Using a 4 strand weaklink on a glider as advocated for heavier pilots effectively means you don't have a weaklink and will end up with the rope.

The other point Deepfloat makes is that while doing lockout training, the weaklink often will break during the maneuver, despite any physical analysis that says typical tow forces will not be exceeded. Having done many physical analysis myself, I know how frail the chain of assumptions can be. Deepfloat's conclusion is that making weaklinks too much stronger may result in cases where the link could have saved a pilot from a lockout because things happen so fast.

In my particular field of research, the modelers always trust the experimental data, while the experimentalists are cautious with their own data but tend to put too much trust in the model results. This is because each group are honest scientists who know how easy it is to screw things up so are skeptical of their own results.

Tad, you sow doubt because you think you are absolutely right. This is intellectually dishonest. You will be better served by trying to knock down your own house of cards. You give the idea lip service by challenging people to offer counter examples, then proceed to ignore them.

In view of Deepfloat's observations I would say that your scaled stronger weaklink ideas make sense up to an upper limit where the tug is put in jeopardy. After that it just sucks to be heavy.
Brian Vant-Hull
Tad Eareckson
Posts: 304
Joined: Wed Feb 09, 2005 8:50 am

Post by Tad Eareckson »

Brian,

Yeah, well we can slide back out of approaches too - as long as we maintain a dialogue. And - even now - people are still listening. So let's try to recover from that bit of unpleasantness and get this train moving again.

With respect to Deepfloat...

Although I haven't checked lately, Ridgely tugs have always - to the best of my knowledge - used a doubled loop of 130 Greenspot - four strands - incorporated in the bridle. That translates to 400 pounds of tow line tension.

The tandem gliders use the same thing but because the bridle forms a more obtuse angle that weak link only translates to about 348 pounds. That and the fact that the spinnaker shackle chews things up pretty much assures that the tow line stays with the Dragonfly.

While the tug may be multiples of the complexity of the glider the relevant structures aren't. And there's a breakaway in the tow mast in any case.

My feeling is that the tug is supposed to be there to accommodate the glider - not the other way around. If that structure won't allow me to tow at 1.4 Gs - beef it up.

In any case... I'm not worried about ending up with the rope because the chances that I'll ever get that far out of whack before releasing are zilch. They're even less than Karen's 'cause her release actuator is mounted (poorly) on the downtube, she's never broken a weak link, and I've always got a finger on the trigger.

>
Deepfloat's conclusion is that making weaklinks too much stronger may result in cases where the link could have saved a pilot from a lockout because things happen so fast.
<

I'M STILL NOT HEARING ANY RELEVANT INCIDENT REPORTS.

Lockouts don't kill people. The ground kills people.

A weak link is not there to keep you from hitting the ground. Down low you may get LUCKY and have a weak link break in such a manner as to let you off the hook. You may also get UNLUCKY and have a weak link pop at just the wrong time - as in the Danny and Bob scenarios - and get killed.

That part of the tow MUST be kept under control by the pilots pointing their planes in the right directions and actuating releases at appropriate times. WEAK LINKS CANNOT AND MUST NOT BE THOUGHT OF IN TERMS OF LOCKOUT PROTECTION.

>
The other point Deepfloat makes is that while doing lockout training, the weaklink often will break during the maneuver, despite any physical analysis that says typical tow forces will not be exceeded.
<

James Freeman:

>
Lockouts can and do occur without increasing tow tension up until the point where the glider is radically diverging from the direction of tow.
<

Yeah, the weak link will ALWAYS break if the lockout progresses long enough. The problem is that the point at which would have happened may be twenty feet underground.

--

James Freeman:

The purpose of a weak link is solely to prevent the tow force from increasing to a point that the glider can be stressed close to or beyond its structural limits.

Stuart Caruk:

Will weaklinks prevent injuries to pilots who have crappy launch skills and get drug across the ground on launch? Will they protect against lockout, or even a vertical lockout if the pilot is dumb enough to have the line come tight going downwind? Nope and Nope. The weaklink protects the equipment to ensure the pilot has something left to fly. It's up to the pilot to decide if they are capable of flying it. Weaklinks don't make better pilots than reserves do, and frankly they are in about the same class.

I think a weak link is essential. Its sole purpose is to ensure that maximum designed tow forces are never exceeded.

Steve Kroop:

A weak link is there to protect the equipment - not the glider pilot. Anyone who believes otherwise is setting himself up for disaster. The pilot actuating his release is the way to save himself.

--

I'm telling you, Brian. These people have it right and just about everyone else has it wrong. Let's not make this about ME. This is not about ME thinking I'm absolutely right. This is about ME KNOWING THEY ARE ABSOLUTELY RIGHT.

>
You give the idea lip service by challenging people to offer counter examples, then proceed to ignore them.
<

No, I'm doing the best I can but have been pretty overwhelmed. I haven't even BEGUN to deal with Janni's Lucky Break. Stay with me.

Now let's take a look at several things Deepfloat DIDN'T say...

"There I was. Thought I was gonna die..."

"There he was. Thought he was gonna die..."

"There was this guy down at Quest in '03. There he was. Thought he was gonna die..."

>
In view of Deepfloat's observations I would say that your scaled stronger weaklink ideas make sense up to an upper limit where the tug is put in jeopardy. After that it just sucks to be heavy.
<

Down low ANY glider with ANY weaklink can put ANY tug in jeopardy. That's why there's a release on that end.

As to the weak link...

The tug pilot can use whatever goddam weak link he wants. The only relevant variable with respect to what the glider chooses is the matter of who gets to keep the rope.

Now let's step back a minute.

I'm not saying anything about the UPPER limit. The USHPA has already codified that as 2.0 Gs. Deepfloat probably doesn't like that so he should probably try to get it lowered. I would oppose that 'cause I think the FAA knows what it's talking about. But I'm only pushing for 1.4.

What I'm saying is we need to specify a LOWER limit. The USHPA says that's 0.0 Gs. As ultimately safe as that is I think it's too low. If you start going up things start getting very dangerous for a while but the risk level goes way down by the time you get to 0.8. I'd push for 1.0 but could live with 0.8 where the FAA has it.

Anybody got a problem with that?
brianvh
Posts: 1437
Joined: Wed Feb 09, 2005 2:32 pm
Location: manhattan, New York

Re: Weak link question

Post by brianvh »

Actually, Deepfloat said that during multiple lockout practices the weaklink broke before getting to the release. Too many to catalogue individually. The tension definitely increases above tow forces for a significant percentage of lockouts.

Also, the tug knot looks like 4 but it's actually 3 strands. Said that right up front.
Brian Vant-Hull
Tad Eareckson
Posts: 304
Joined: Wed Feb 09, 2005 8:50 am

Post by Tad Eareckson »

Brian,

I really appreciate having a person for whom science and math are distinctly separated from opinion (as in "It's my opinion that the Earth is six thousand years old and my opinion is just as valid as yours." - which tends to be the norm around here) but I'm hoping that you're planning on responding to my post sometime in more depth than that. I'm putting a lot of effort into and taking a lot of stress as a result of this correspondence and I'd like to hear either concessions or challenges to the points I'm making.

What tends to happen in these exchanges is that I make irrefutable points and the opposition just silently slinks away and the less qualified bulk of the community always slides back to it's perennial "Well, Guy B has WAY more airtime than Guy A so he must know what he's talking about." position and stays as stupid as it was when it started out.

Lemme deal with this last issue you just brought up and then hopefully we can drop it because it's pretty much TOTALLY MEANINGLESS. I had reread your previous post before logging on this morning, said "WAIDAMINUTE!", and already written a response which I will now modify a bit.

I'm a REALLY GOOD knot person. I know when I'm looking at four strands and I know when I'm looking at three. If Ridgely tugs are using three strands they switched fairly recently 'cause I can tell you to a certainty that every time I've checked there's been a doubled loop of Greenspot Double Lark's Headed onto the bridle. And I'm DAMNED sure they're still using the same thing they're using the same thing on the tandem gliders' bridles. So I'd be real surprised to find out that they're using three in the front and four in the back.

I'm also pretty damned sure they've never actually tested those two configurations because until I pointed out the reality of the situation they were basing their strategy on the assumption that the weak links strength is determined by multiplying 130 pounds by the number of strands. This assumption is completely detached from reality and is the root of just about all of our problems.

I myself HAVE actually tested these configurations and - very surprisingly - while a doubled loop / four strands tests very consistently right around 200 pounds direct load, I got 225 for three.

Now, with respect to the solo lockout drills...

For all but the pixie end of the range of solo pilots the failure of the one size fits all weak weak link is an almost totally random event. They can and do blow anywhere at any time between and including the moment the tug budges forward through separation from the dolly to well into a lockout so severe that it gives one pause concerning one's continuing participation in the sport.

>
The tension definitely increases above tow forces for a significant percentage of lockouts.
<

I know this conflicts a bit with the Freeman quote I referenced but...

Well, DUH! Yeah, if you're going this way and the tug's going that the rate of increase in tension will soon become astronomical (which is why, as Dr. Freeman also says, there isn't much of a penalty in terms of roll and/or delay in significantly beefing up your weak link). So what?

The problem is - while in practice and up high were it doesn't matter - down low where it does, lockouts can and do progress to the point at which the pilot is transformed to a lifeless pulp with a one size fits all weak link stressed to only half of its capacity.

So you'd think that those pilots who were unable to release before the weak link failed would have figured out that the weak link can't be counted on the keep them alive during the critical part of the tow 'cause - as far as the exercise was concerned - they got killed.

>
Actually, Deepfloat said that during multiple lockout practices the weaklink broke before getting to the release. Too many to catalogue individually.
<

>
THE WEAKLINK BROKE BEFORE GETTING TO THE RELEASE
<

I CANNOT FATHOM why anyone in his RIGHT MIND would elect to launch with a release HE HAS TO GET TO. The tugs don't do it - Why do we?

On that issue...

http://ozreport.com/pub/fingerlakesaccident.shtml

Where's his hand? Where's the release actuator?

>
If your position is logically correct, people will come around...

YA STILL THINK?

>
brianvh

2008/11/10 13:03:30

After some thought and prodding by an anonymous source I want to lay things out as clearly as I can.

1. We definitely want links that will break when there's a sudden snap in tension caused by such non-normal flight scenarios such as the cart getting hung up in a pothole... In these cases the weak link protects both the pilot and equipment.
<

WRONG.

During the insomnia session two nights ago I figured out how to explain why the weak link can't do you any good in that sort of situation.

In fact, the ONLY difference a stronger weak link can make is to REDUCE the severity of the accident.

Don't worry, Peter Birren doesn't get this either.

>
2008/10/27 19:47:08

I know about this type of accident because it happened to me, breaking 4 ribs and my larynx... and I was aerotowing using a dolly. The sh*t happened so fast there was no room for thought much less action. But I wasn't dragged because the weaklink did its job and broke immediately on impact.
<

The critical element in both of these accidents was not the weak link.

The critical element was topsoil.

Neither of these pilots were hurt 'cause they were dragged. Dragging is a relative non issue until you get to the barbed wire fence at the upwind end of the runway.

These pilots were mangled SOLELY as a consequence of the the ultra power whacked induced sudden stop.

We agree that no weak link on the planet can prevent the power whack itself. Right - just look at the pictures.

Things start getting real ugly when the nose digs into the sod. The first thing that happens is that the weak link pops. The next thing is that the pilot - still moving at twenty miles per hour - is gonna swing into the fore underside of the glider going zero miles per hour. Lessee... twenty minus zero... TWENTY! The pilot hits the glider at a closing speed of twenty miles per hour. Lips, larynxes, ribs, necks... whatever.

OK, rewind the tape. This time we're gonna use a quadruple loop weak link and do it again. Same ultra power whack nose plant. But this time the weak link (and - for argument's sake - the back end of the Dragonfly) holds. So for several seconds the glider continues on plowing a furrow at five miles per hour. You still swing into the keel but at a closing speed of only fifteen miles per hour this time.

So the dragging that terrifies everyone so much is actually your best friend and the tea bag string in which everyone places so much misplaced trust is - once again - YOUR WORST ENEMY.

Still having trouble?

Repeat the experiment out on a frozen lake and you don't get hurt at all UNLESS the weak link breaks.

Pretty cool, huh?
brianvh
Posts: 1437
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Location: manhattan, New York

Re: Weak link question

Post by brianvh »

Actually on a frozen lake you wouldn't get hurt if the weak link breaks because you and the glider will still be doing the same thing since neither is being influenced by friction. On ordinary grass you may be right but it's a complicated enough situation it needs many repeated experiments. Have at it. ;-)

If as you say the force increases so quickly a 1.4 G link will be broken a second after a 0.4 G link, then I think your points are logically valid. But anyone (such as Deepfloat and Janni) who has experienced a lockout with a weaklink break will have the gut reaction that weaker may be better. I see it as my job to bring up all objections so they can be discussed without all the name calling destroying the arguments.

Don't know details about the 3 versus 4 string. Table it unless I hear more.

Anyway, I think you may have convinced some people that they can scale up their link without dire consequences. May be the best you can hope for.
Brian Vant-Hull
RedBaron
Posts: 625
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Re: Weak link question

Post by RedBaron »

If as you say the force increases so quickly a 1.4 G link will be broken a second after a 0.4 G link, then I think your points are logically valid.
What makes this discussion obsolete is that every argument is based on assumptions which may or may not be valid in any particular case.
A stronger weak link breaking a second later can kill you in a lockout event where that one second places you past the point of no return. That same weak link could save you during a rough launch where a weaker one will break and have you crash. Note that the crash is largely the result of your poor landing skills and judgment rather than the fact that the weak link broke. The scary stuff about weak links not breaking under gradual increase of tension does not worry me, simply because I don't believe that things get out of control in a smooth, gradual way in smooth conditions. Ergo: You can paint death scenarios for whatever weak link strength you use. It makes no difference. If everybody flew with Tad's weak links some would crash and a few would die, too. It's hang gliding, stupid!
#1 Rogue Pilot
brianvh
Posts: 1437
Joined: Wed Feb 09, 2005 2:32 pm
Location: manhattan, New York

Re: Weak link question

Post by brianvh »

Tad's point is that non-lockout breaks near the ground are more common than lockout breaks.

(prob of non-lockout break)*(prob of injury due to break) > (prob of lockout nonbreak)*(prob of injury due to nonbreak)

Weather the statistics is correct is debatable. I feel they probably are correct.

Putting the mathematical supposition into words:
"The chances of sustaining serious injury due to a non lockout break near the ground is greater than the chances of having a lockout near the ground and the weak link saving you in a case where you don't have time to release before it gets bad."

The links are more likely to break when the glider gets kicked around, making landing skills a bit less relevant since you may be in a bad situation plus the nose angle used for towing is at stall when the link releases. Most people land on the wheels after a low link break.

People who have downtube mounted releases are more likely to feel they can't release before a lockout than people who have basetube finger pull actuated releases. Tad tried beating that horse a while ago and gave up. may be time to give up on this one.

where the weak link strength sweet spot is located may be a matter of opinion, but if the links are breaking on a regular basis you may want to scale up the strength a bit. Is that such a terrible concept?
Brian Vant-Hull
RedBaron
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Re: Weak link question

Post by RedBaron »

Nobody doubts that a base tube mounted release is better than one that sits on the down tube. That's not the issue here.
As for the rest, you can run your physics equations all day long, I will always trust the empirical data of my own experience and 8 years of safe tow operations at Highland more. I've had a number of close-to-ground weak link breaks that were all non-events. They all broke either for no reason or before the situation got bad. In at least one of those cases a stronger weak link would have made my situation worse. And I'd much rather crash coming off the cart stalled than locking out and nose-diving into the ground because of that extra second. One second can be a LONG time. It's totally beyond me why neither you nor Tad get that. Perspectives change a lot when you don't tow stable gliders anymore, Brian. I'd have a padlock for a weak link if I towed on a Falcon.
#1 Rogue Pilot
brianvh
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Re: Weak link question

Post by brianvh »

I tried towing a K2 once, if you recall. Perhaps the hardest glider to tow ever made. 5 breaks in a row, one of them was at treetop level and I had to do a quick and low 360 to avoid gliding into the treeline in front of me (may not have been necessary). I wish I could remember if that was the one time I was scared and released. Having to land before you are planning to when a glider starts acting skittish is not a non-event.

Anyway, the point is that if you are constantly breaking weak links, especially if you are a heavier pilot, scaling up the strength is an option so long as you don't go above the link on the tug end. We lighter pilots have been towing with proportionally stronger links for years, and I think we've been happier. Perhaps the main reason I'm a convert is because I don't feel I have to change a thing. :)

BTW Tad, I haven't seen a catalogue of broken aluminum due to weak link breaks. Fair's fair.
Brian Vant-Hull
Tad Eareckson
Posts: 304
Joined: Wed Feb 09, 2005 8:50 am

Post by Tad Eareckson »

Brian,

On the ice the glider's gonna slow down faster if the weak link breaks. Nobody needs to do any testing on the grass 'cause there's no freakin' way that something in front of the glider won't break. It's not complicated - just think about it.

As to gut reactions... If weaker is better why does the FAA put the floor at 0.8? Why is it illegal to tow at 0.6? Who are the people having minor accidents on tow? Karen, or everybody but Karen? What would have happened to Janni if he had been in Danny's situation with the same loop of Greenspot? Danny was scared shitless that the weak link would break. There can be no doubt in anybody's mind that this weak link that Janni thinks can do his job for him would have failed and he WOULD have cartwheeled.

We gotta do a lot better than gut reactions.

Janni,

>
I came off the cart crooked...
over-controlled...
thought I was in control until it broke
<

This was not a micrometeorological problem.

This was not an equipment problem.

This was a personnel problem.

Relying on a weak link to compensate for an inability to control a glider is not a good strategy for sustained participation in this sport.

Try running that concept by Sunny if you want a second opinion.

You need a weak link that holds about 165 pounds of line tension just to get moving and if you don't think that's enough force to lock you out and kill you several times over you've got another thing coming.

Steve Kroop:

>
A weak link is there to protect the equipment - not the glider pilot. ANYONE WHO BELIEVES OTHERWISE IS SETTING HIMSELF UP FOR DISASTER.
<

Ya know who Steve Kroop is? Ya think there's a ghost of a chance he knows what he's talking about better than you do? I sure as hell do.

Brian,

>
Anyway, I think you may have convinced some people that they can scale up their link without dire consequences. May be the best you can hope for.
<

I HAVE convinced some people to scale up their weak links. But one of the other things I'm hoping for is to get them to understand - as Danny does - that there can be dire consequences to NOT scaling them up to something reasonable.

I spent about an hour and a half getting that point across to Bob Buchanan at the fly-in last summer. He and is Exxtacy had just popped ten in a row. The light bulb came on bright when I pointed out that he and Karen should probably not be flying the same piece of string and I got him up to about 1.1 Gs.

But then some idiot got to him afterwards and dropped him back down well below 0.8. So I'm wondering how come nobody 'cept Janni gives a flying fuck about Karen's safety (1.22).

Janni,

>
A stronger weak link breaking a second later can kill you in a lockout event where that one second places you past the point of no return.
>

You can release long before the time split between the weaker and strong links with a half decent release configuration like Matthew, Brian, and I have.

If you were really concerned about your safety at launch you'd be flying with a half decent release configuration like Matthew, Brian, and I have. The safety margin that gives you dwarfs to total insignificance any real or imagined benefit you get from the tea bag string. But:

>
We wouldn't be flying if it wasn't dangerous.

Janni Papakrivos
Flight Director MHGA
<

Yeah, that would explain lotsa stuff in this conversation. I can't understand why - with that attitude - you don't keep the brake lever on the downtube AND beef up to 3.0 Gs.

Brian,

>
The chances of sustaining serious injury due to a non lockout break near the ground is greater than the chances of having a lockout near the ground and the weak link saving you in a case where you don't have time to release before it gets bad.
<

I know of no instances of anyone getting locked out near the ground so fast that there wasn't time to release. And Janni wasn't locked out and his situation was entirely self inflicted.

>
People who have downtube mounted releases are more likely to feel they can't release before a lockout than people who have basetube finger pull actuated releases.
<

This is not a "feeling". They obviously no fucking way can get off as fast as we can. Especially of they fall to the other side where they can't even get back to it. People who ELECT to fly that way are saying, "Hell, I don't need all that safety margin." I'm wondering what the hell the upside to doing it that way is.

>
where the weak link strength sweet spot is located may be a matter of opinion
<

I don't think so. I think the FAA knows what it's talking about and that makes the sweet spot 1.4 Gs. Even with the USHPA's floor of 0.0 the sweet spot is 1.0.

1.0 is what the guys at the flight line CLAIM they're handing out to Karen, Kirk, Bob, and Janni so why don't we at least use something that ACTUALLY IS 1.0?

Janni,

>
Nobody doubts that a base tube mounted release is better than one that sits on the down tube.
<

BUT HARDLY ANYONE ACTUALLY CONFIGURES THEM THAT WAY.

>
I've had a number of close-to-ground weak link breaks that were all non-events. They all broke either for no reason...
<

To the dozen people in line behind you they're not non-events. The five minutes you waste EACH TIME costs a cumulative hour of airtime. The practical effect of one of those "non-events" is just about always that somebody misses the opportunity to soar. You're fucking up some really good days for a lot of people and - again - the only time you appear to have benefited from a pop it had resulted from a situation of your own making.

>
One second can be a LONG time. It's totally beyond me why neither you nor Tad get that.
<

Exactly. One second IS a LONG time. And I'd rather spend it twisting my hand and taking care of the problem than waiting around HOPING that something good will happen. But - again - I don't have to wait for that second either. I was off a long time before that.

>
Perspectives change a lot when you don't tow stable gliders anymore, Brian.
<

I tow a stiffer handling glider than you do and feel - and AM - a lot safer than you are.

Brian,

>
We lighter pilots have been towing with proportionally stronger links for years, and I think we've been happier.
<

You HAVE been happier. And since I moved up to Karen's G ballpark I'm infinitely happier - if and when Janni gives me the opportunity to get in the air. I'm no longer scared shitless of every little bump that comes my way like I used to be. I'm in control now.

>
BTW Tad, I haven't seen a catalogue of broken aluminum due to weak link breaks. Fair's fair.
<

On my first flight at Ridgely on their first day of operation I broke their first downtube in a downwind landing following a break. I've watched Dennis Scheele and Victor Koshmaryk break others. All popped for no reason.

But look at it this way. You launch and planes twice as often per hour of airtime - you're gonna get twice as much damage and twice as many injuries and fatalities.
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Re: Weak link question

Post by eggzkitz »

Tad,

How are you fingers doing? Any carpal tunnel symptoms?

You guys are entertaining, even if my never-towed in my life lame butt doesn't understand what the issue is.

Sometimes we just agree to disagree.

Aloha,
Jeff
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Post by Tad Eareckson »

Jeff,

Thanks so very much for the non hate mail note. Such is always a pleasant surprise and rare treat.

The fact that you've never towed in your life gives you a HUGE advantage in understanding the issue. This is nothing but basic physics and simple logic. Brian's starting to get this but is having to overcome the brainwashing damage done by a couple of decades worth of this culture getting and doing it wrong.

A kid with a kite can get this a lot better and easier than an experienced tow pilot.

>
Sometimes we just agree to disagree.
<

Nah, not when it's an issue of science - somebody's right and somebody's wrong. The really smart tow people all converge on this matter. The guy who got his doctorate figuring out how to tow hang gliders is coming my way.

The wrists are doing a whole helluva lot better than than the eyes, the AOL dialup connection, and the computers. Huge problems with the latter two. The PowerBook G3 died out from under me yesterday and I had to play musical hard drives with a couple of Power Mac 7300s to get something that worked.

Glad you're enjoying it. Stay tuned.
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Re: Weak link question

Post by Danny Brotto »

This thing about the FAA regs on weak link strength does in fact allow for a “one-size-fits-most” solution. I am not saying that the FAA recommendations for sailplanes scales appropriately to hang gliders; just want to clear up the reg.

The FAA regs is for the weak link to be between 80% and 200% of the maximum certificated all-up mass of the glider being towed.

The maximum certificated all-up mass of the small Falcon 3 is 235 lbs (45 lbs glider and 190 max pilot.) So using the FAA guideline, a weak link for the small F3 should be between 188 lbs and 470 lbs.

The certificated all-up mass of the large T2 is 358 lbs (73 lbs glider and 285 max pilot.) So according to the FAA, a weak link for the large T2 should be between 286 lbs and 716 lbs.

Combining the two gliders allows for a one-size-fits-most weak link between 286 lbs and 470 lbs.

There are plenty of hang glider pilots flying within the 80% to 200% FAA guideline (or their particular glider rig) that are snapping weak links regularly. Snapping weak links in sailplanes happen but it’s not common. I suspect there is some other dynamic that needs to be applied to hang gliders.

I mass out at about 235 lbs so my rig (theoretically at least) has me at a 1.1G link. I have a faint recollection of snapping a weak link once but other than that, my links have stayed intact. I’m rather fastidious about changing weak links every few flights and also not letting them drag around so as to avoid abrasion.

Danny Brotto
RedBaron
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Re: Weak link question

Post by RedBaron »

And Janni wasn't locked out and his situation was entirely self inflicted.
Everything in this sport is self-inflicted.
To the dozen people in line behind you they're not non-events. The five minutes you waste EACH TIME costs a cumulative hour of airtime.
Thanks for confirming Cragin's suspicion.
You can release long before the time split between the weaker and strong links with a half decent release configuration
This is a matter of experience, skill and awareness. I for one always tried to correct the situation rather than get off tow right away. I suspect most people do. I am still inexperienced, so I think it would be way too late for me when I realized I had to get off. Luckily, my tea bag weak link doesn't hold that long.

As for Brian's and Buchanan's examples, I'm as heavy as they come, I'm a whopping 300 lb. package. I towed in nasty conditions. If you break 5 in a row you're either doing something fundamentally wrong or flying in conditions that are fundamentally wrong. None of these examples provide evidence that our weak links are too weak.
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Tad Eareckson
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Post by Tad Eareckson »

Danny,

Yeah, hang gliders can do a one-size-fits-most - but the single loop of Greenspot ain't it.

>
The maximum certificated all-up mass of the small Falcon 3 is 235 lbs...
<

I think for the purposes of this drill we oughta min out a Falcon 140 - 42+120=162. Allowable max tow line tension range - 130 to 324 pounds.

So for the one size fits most we narrow the overlap range to 286 through 324 - a target area spanning 38 pounds. That's cutting things a bit fine.

>
There are plenty of hang glider pilots flying within the 80% to 200% FAA guideline (or their particular glider rig) that are snapping weak links regularly. Snapping weak links in sailplanes happen but it's not common. I suspect there is some other dynamic that needs to be applied to hang gliders.
<

These hang gliders that are snapping weak links all the time are NOT flying at 0.8. These weak links do not retain their integrity for medium to heavy gliders. These gliders are snapping weak links at 0.5 and less.

http://ozreport.com/forum/viewtopic.php?t=13573

That's the dynamic that's going on.

>
I mass out at about 235 lbs so my rig (theoretically at least) has me at a 1.1G link.
<

I don't know whether you tow two point or off your shoulders. I have you at 1.04 if the former, 1.19 the latter. The fact that you didn't die behind Sunny is a fair indication that whichever of those numbers is relevant is a safe low end. But I'd still feel better at 1.4.

But back to the issue at hand...

A DOUBLE loop of Greenspot IS a pretty good one size fits most. It would max out Karen at 2.0 if she towed one point but only puts her at 1.74 as is and it puts me and Janni at 1.09, 1.25 off the shoulders.

Janni,

Remember about a year ago when you gave me a lot of grief for saying:

>
Now let's multiply him (Danny) by 1.5 to approximate Janni's hook in weight...
<

Looks like I was just about right. A bit low actually.

>
Everything in this sport is self-inflicted.
<

Yeah, I pretty much totally believe that and wouldn't be flying if I didn't (hence the issue I took with the "shit happens" philosophy expressed last spring).

But some stuff is WAY less self inflicted than other.

Putting a glider out of control is way more self inflicted than failing to check your six before launching and getting bitten by the Mother of All Thermals just off the cart. John Dullahan had this happen to him, did everything else right and fast, and still got a broken wrist out of the deal. He got rolled bad and his tea bag string didn't break. He released. If he had relied on it breaking he would have probably ended up like all the witnesses thought he would.

Bob Koshmaryk got nailed by a dust devil from the side so bad that a tip dragged. He got into a series of oscillations but took control of what was left of the situation and RELEASED at exactly the right time. If his tea bag string had broken at exactly the wrong time it would have been ugly.

>
Thanks for confirming Cragin's suspicion.
<

Cragin's SUSPICION? Too bad he never reads the material upon which he comments. Then he wouldn't have to rely on suspicion.

Go back and read my first post in this thread.

Also go back and read THE first post in this thread. I wish everyone had Kirk's concern for participants other than himself.

I've never made any secret of my resentment of this bullshit situation. I've been consistent in that position for years. You stick around at Ridgely long enough and you're gonna start understanding where I'm coming from.

>
This is a matter of experience, skill and awareness. I for one always tried to correct the situation rather than get off tow right away. I suspect most people do. I am still inexperienced, so I think it would be way too late for me when I realized I had to get off. Luckily, my tea bag weak link doesn't hold that long.
<

I am quite sympathetic to your position and I agree with your assessment of how most new towers are likely to react. But here's the BIG problem:

>
Luckily, my tea bag weak link doesn't hold that long.
<

LUCKILY, your tea bag weak link DIDN'T hold that long. There is every likelihood that it WILL next time. You can't sustain a string of luck (pun not intended initially but it works so well) to ensure your safety.

>
Cragin Shelton

NEVER TRUST A WEAK LINK!

Expect two things from your weak link:

(1) It will break unexpectedly at the most inopportune time, with no warning adn no indicaiton of a flight problem.

(2) It will hold strong and fast whenever you move into a lockout. You must never plan or expect on a weak link break. It may well not break when you fly with that attitude. As Joe said, if your situation is new to you and not right, get off tow!

I have never had an instructor use those words to me, but all towing instructors I have worked with have given that message in some form. Pagen & Bryden address it clearly in _Towing Aloft_.

...

So, to repeat: Never trust a weak link. Be prepared to fly off tow in a surprise break at all times when attached, and be prepared to hit the release at all times in case of a surprise attitude change.
<

He's got everything EXACTLY RIGHT except the (1) bullshit which is a consequence of using Karen's weak link.

>
A weak link is there to protect the equipment - not the glider pilot. Anyone who believes otherwise is setting himself up for disaster. The pilot actuating his release is the way to save himself.
<

Note the consistency in positions.

Here are the relevant parameters defined in the USHGA Aerotowing and Tug Pilot Guidelines in which you must be able to release immediately...

Glider is low and has diverged more than twenty degrees from the tow.
Oscillation worsens at low altitude. Release as the glider is starting to recover from a cycle.
Glider rolls past 45 degrees.
At takeoff the glider climbs so far above position that it threatens to nose in the tug.
When low the glider fails respond to a roll correction within a second.

Learn them, visualize them, and be prepared RELEASE as soon as you recognize one of them happening.

If experience and skill are still such issues that you are not confident of your ability to control the Litespeed at launch then borrow a dumbed down glider for a few pattern tows. Don't expect the weak link to compensate.

>
If you break 5 in a row you're either doing something fundamentally wrong or flying in conditions that are fundamentally wrong. None of these examples provide evidence that our weak links are too weak.
<

When a glider breaks a weak link straight and level in smooth air it is one hundred percent proof positive that his weak link is to weak. He's doing something fundamentally wrong but he's doing it before he gets on the cart.

As to flying in conditions that are fundamentally wrong...

IF THEY'RE NOT FUNDAMENTALLY WRONG THEY'RE NOT WORTH TOWING IN.

The more fundamentally wrong the better.
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Re: Weak link question

Post by RedBaron »

Dude, what part of "I'm big and my weak links never break in smooth and level flight" did you not get?
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Tad Eareckson
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Post by Tad Eareckson »

Dude,

What part of "I'm bigger, a way more experienced and better ATer, and my links break all the time in smooth and level flight" did you not get?

Now, lemme straighten out a bit and expand on my smart ass response to your clueless smart ass response.

Need to make that past tense of course 'cause I stopped breaking weak links shortly before my brain started kicking in a couple of years ago.

I must apologize 'cause up to this point I had assumed that you were interested in thermalling. I now see that you're interested only in sled rides so I'm revising my recommendations to a strategy which will work out great for all concerned.

Get a Falcon or some other entry level glider and keep it at Ridgely. It'll keep you out of trouble at launch and you'll have absolutely no need for all that performance you're packing now. Keep the Litespeed at home and use it for Strasburg to Harrisonburg runs.

Transfer your Quallaby release and velcro the brake lever up on the downtube as it's presently configured. Neither the extra time and effort it takes to get to it nor the fact that it can spin on the tubing will matter. The tug pilot will always be able to do your job for you - faster, smarter, and better.

Limit your towing to early mornings and late evenings in surface winds of 5 mph or less, ESE or WNW.

The chances of you experiencing a no fault lockout or oscillation will be about zilch and the self inflicted variety almost so.

It may or may not, but if your weak link does happens to break for no reason you land, get back on the cart, and tow again. BFD! Time is seldom critical at those times of day - 'cept you don't wanna miss the spectacular view of the Chesapeake you often get with the sun setting beyond it.

You'll stay extraordinarily safe and the fuck out of the way of the REAL pilots who wanna get up higher than they were dropped off, extend their flights beyond twelve minutes, and max out their airtime earned to gasoline burned ratios.

And you'll never hafta burden your delicate mind with the complexities of the safety issues put forth by the likes of Kevin, Danny, Brian, Paul Tjaden, me, James Freeman, Steve Kroop, Donnell Hewett, and anybody else who knows what he's talking about.

You are hereby absolved from further participation in this thread.
brianvh
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Re: Weak link question

Post by brianvh »

Umm, Tad....there are still some things you clearly don't get.

I hereby absolve myself of participation in this thread because the main contributor has no idea how to behave in polite company. This may be permanent and apply to other threads of like nature. I apologize for prolonging this thread by my previous responses.
Brian Vant-Hull
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Post by Tad Eareckson »

Ya know, Brian, there are still lotsa things that lotsa people people don't get.

One of my goals here is to steer Janni (and everyone else for that manner) away from a luck based survival strategy and help him become a better, smarter, safer AT pilot.

Janni's Lucky Break may very well prove to have been the worst thing that ever happened to him in hang gliding. Maybe he'd have ultimately been a LOT better off if his tea bag string had held - and I can provide GPS track log data to prove beyond all doubt that in a low level lockout situation it is totally capable of doing that beyond any hope of survival - and he survived with nothing more than major bruises 'cause his Litespeed absorbed most of the impact in the course of getting totaled.

I've got a REALLY GOOD analogy.

Picture it. 2005/09/17. McConnellsburg. Bill Priday is approaching the Pulpit south ramp with his glider on his shoulders and his carabiner dangling behind him.

I'm gonna give you a time machine but it's the economy model and you've only got two choices:

1. Change nothing.

2. Interfere and let him go off unhooked.

And, of course, the answer, given what we all know is gonna happen fourteen days later, is OBVIOUSLY - 2.

We know - statistically - that it's possible to go off the much higher north ramp unhooked, spend a few months of hospitalization and recovery, and resume a very active hang gliding career.

But here's what happened...

He got intercepted by two USHGA Observers who got him connected and sent him off with a fine launch over the scree and the implicit message:

"Hook-in check? Hell, why bother? Ya just had a HANG CHECK fer chrisake! Why worry about the USHGA SOPs? Nah, just do that hang check and you're good to continue carrying your glider into position and launch without another care in the world."

How he or anyone else ever gets off the goddam training hill with a signature on his Hang I rating form is totally fucking beyond me. But he keeps getting away with it and thus having negative reinforcement. And he gets more negative reinforcement from - not one but - TWO - count 'em - TWO Observers. And two weeks later the bottom falls out from under him at a launch at which there is virtually no possibility of survival. And he doesn't.

One more victim of this stupid broken culture.

So, likewise, Janni launches with fuzzy understanding of emergency situations, a glider which is beyond his capability to safely aerotow, and a release which complies with the USHGA SOPs and a daffodil's concept of common sense no better than the foot launch procedure which got Bill snuffed out and comes out smelling like a rose solely because of a dice roll.

And he comes away with this ABSOLUTELY DEADLY negative reinforcement that it's OK to do the hang check and skip the hook-in check - OOPS - I mean - count on a weak link break to compensate for getting into serious serious trouble SOLELY as a consequence of violating about FOUR - count 'em - FOUR provisions and requirements of USHPA SOP 12-02.10.

And, of course, this negative reinforcement spreads like the plague through the AT community which has been baptized in a total cesspool of misinformation anyway.

I've worked my ass off to understand everything I can about the physics, mechanics, procedures, and ergonomics involved in aerotowing hang gliders. What I do is identify the best minds in the sport, parasitize off of everything they have to offer, compile and organize the information, and build on top of whatever I can. Nobody on this turf has a snowball's chance in hell of ever laying a glove on me. 'Cept for Steve - he comes up with a lot of stuff way ahead of everybody else and I've had to follow his lead on a good handful of issues.

Earlier you accused me of giving Janni's (negatively reinforced and disastrous) take on this issue short shrift. I - and you - and Danny - have tried to lend him the benefit of our experience and understanding that understrength weak links are potentially lethal. Yesterday I put a lot of effort into explaining to him why "Anyone who believes otherwise is setting himself up for disaster."

As seems to have become a pattern he ignores the core issues of this topic and comes back with a stunningly rude and disrespectful and bizarrely irrelevant twenty-one word crack.

And you've got the gall to criticize ME for my reaction? Like Chris's post was MIGHT have been in the GRAY area? Polite company?!

Brian, I've always GREATLY valued your participation in these discussion 'cause you're often the only one with whom I can have a rational exchange but I'm wondering why you never seem to say much about the attacks but tend to jump all over the counterattacks.

You understand - as few do - that by Janni following this "They can't be weak enough" course of action he "is setting himself up for disaster" and setting an example which, if followed, is very likely to eventually get somebody mangled. So if you decide to walk out of this conversation because you think I'm and asshole - WHETHER OR NOT YOU'RE RIGHT - then maybe you wouldn't have been as valuable a contributor as I had hoped anyway.

Maybe you're the one who needs to do some soul searching.
RedBaron
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Re: Weak link question

Post by RedBaron »

Maybe he'd have ultimately been a LOT better off if his tea bag string had held - and I can provide GPS track log data to prove beyond all doubt that in a low level lockout situation it is totally capable of doing that beyond any hope of survival - and he survived with nothing more than major bruises 'cause his Litespeed absorbed most of the impact in the course of getting totaled.
No, but something tells me that your fuel supply had been a lot better off if that had happened. Sorry, dude, but how is it my fault that my weak link consistently breaks when it's supposed to?
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hepcat1989
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Re: Weak link question

Post by hepcat1989 »

Tad, Bill did try to launch at the Pulpit Fly-in unhooked... Observers caught him.......Launched unhooked at Whitwell... No one caught it. Why? Not why did no one catch it, but why he did it at all.......Why?.......... Was it adrenaline? Was it rushing? WHY?.............. From that point on I check ALL HOOK- INS! ALL OF THEM! The FEAR of launching unhooked makes me hook in!I NEVER put a good looking sky before saving my anus!I SLOW DOWN when setting up and getting ready to go up to launch. This feels taboo to me talking of launching unhooked.IT should be tatooed on the brain, but is it? Tad, I can appriciate what your angle is........ For my own handle of what happened to Bill.... I painted my carabiner floresent orange, and I had my mother sew me up some wraps for my main made out of material from my hunters saftey vest.Wrap around and little velcro tabs. ORANGE. My main is black like Bill's was . It makes it stand out now. It's just something..... I was thinking about Bill.......
Peace, Shawn.
Tad Eareckson
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Post by Tad Eareckson »

Janni,

Let's agree to drop the "dude" thing, OK?

Your first sentence is a bit scrambled but I think I got what you meant. If so, you're nowhere near the top of the list I would select for that sacrificial demonstration. The chance that any given individual is gonna make the point dramatically is microscopic. But it's pretty much a certainty that someone is gonna eat runway sometime down the road. We've already got a reasonably good local approximation.

Your second sentence...

Your weak link - in this incident we know most about - HAPPENED to pop "Luckily" (to use your adverb) at a point at which its doing so was very advantageous to you.

If you have any respect for any of the top people in this line of aviation you must understand that it didn't pop when it was "supposed to".

I'd really like to know where you got the idea that this is the function of the weak link.

When you say "consistently"... I'd really appreciate hearing about these other occasions when your weak link has failed in such an opportune matter.

In any case... I'm telling you - I got abruptly and severely locked out a hundred feet before the meter was about to expire on my ride up and - even with that release system you said all those nice things about last summer - I ended up thirty feet lower than I started out with the weak link (same as yours at the time) still doing just fine.

Again, I hook up at about the same weight you do - a healthy (unhealthy actually) bit more and if that had happened just off the cart the weak link would not have failed when it was "supposed to".

Of course my reaction time as demonstrated wouldn't have EITHER - but I wasn't scared or on high alert statusas I would have been at launch and I'm thinking/hoping I would have done a lot better down there.

I'm not seeing yet that you understand Danny's point from his first post (2008/11/04) that you can die if the weak link pops when the glider is banked with the low wing stalled. I really wish you would address that issue.

I have seen a glider locked out and almost certainly about to die and the winch operator (Jonny Thompson) hit the gas and pulled him out of danger and on up for a routine release.

I was dumbfounded because the solution was so counterintuitive to what I would have thought and done. That's the guy I most want in front of me in a Dragonfly if I ever get into a similar situation. There a probably lotsa others who would do equally well but I can think of two - based upon past actions and statements - that scare the hell out of me.

In that situation I'd also be scared shitless with a weak link of anything less than 1.4 Gs. Yesterday I made the mistake of saying that whatever Danny was using at the time - 1.04 or 1.19 - was OK 'cause he lived. But we don't know how close to failure he was. I want - and have - a lot more margin.

Thanks for staying in. It may not seem like it but I'm your most valuable and loyal friend in this discussion.

Shawn,

I'll get back to you.

By the way, there was a "like this" missing from near the beginning of Paragraph 14 in my previous.
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Re: Weak link question

Post by Danny Brotto »

Shawn

Painting the ‘biner fluorescent Orange is a fantastic idea! Look, it's really the pilot's responsibility to insure he/she is hooked in but when your bud is about to launch unhooked I think it's a great idea to let them know. And making the ‘biner in an obvious color is a sure step in the direction of safety.

As far as negative enforcement, I’ve witnessed (as a crew) at least a half dozen pilots ready to launch unhooked (yup even at Ridgley.) I’ve caught it but rather than just tell the pilot that he’s unhooked, I’ve asked for a hang check. The surprise of flopping to the ground is universal. I’m not trying to embarrass the pilot but mainly provide he/she with something to of significance to reflect upon and approach strategies to avert.

Thanks (THANK YOU) for the great safety tip. I think we should universally adopt your practice of painting the ‘biner orange; I’m going to do paint mine this week.

Danny Brotto
heaviek
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Re: Weak link question

Post by heaviek »

Tad, I am so far behind this thread, I just arrowed to the bottom. I may have alluded to it before, but I do realize the John Kerry-esque flip flop nature of my points of view. Tog is the high risk poster boy. Fate is waiting at Tog's front step for any number of opportunities. He wrote many checks his body couldn't cash. Losing tow force too low to avoid the prop wash could get Tog. Being too aeronautically challenged to properly tow a glider is another. Your right, I have used both examples with the same main character.

I enter these discussions to inject my opinion that all issues should be discussed. 9 times out of 10 I will disagree with what someone has to say because most problem solvers have that thread of male macho that keeps them from seeing all 360 degrees of the issue.

Not having total control at all times always increases risk. If we had total control then the only cause of accidents would be pilot error ;). Losing tow force when you want it is bad, not getting rid of it when you don't want it is bad. I step into these debates to speak against any blanket solution. There is no Snake Oil and Rome wasn't built in a day.

I think the mouth release had some great ideas but was not ready for mainstream. That is why I challenged it.
I think looking at weaklinks is a great idea, but not as a blanket solution. If I challenge you its because I harbor skepticism regarding the cause of some of these weak link breaks. I have my own snobbish tendencies and when I go out to fly I can't help but silently criticize what appears to be pilots getting by with just enough proficiency and equipment to pull it off. I have my preconceived notions, and they cloud by opinions of any tow discussion.

Instead of trying to shout over each other to champion our own safety vendetta, lets champion our vendetta's while promoting the other's. While promoting the weaklink discussion, address pilot skill, and when I push for raising the bar on skills, it will include pushinng for appropriate evolutions in equipment.

Deal?

Kev
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