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Re: missing release

Postby TadEareckson » Fri May 13, 2011 4:45 am

The platform release I'm promoting hasn't been built yet and probably never will be. I'd like to see a couple of solenoids at your hips triggered by a button under a finger connected by a wire running up your sleeve. Push it in an emergency and the whole assembly - no matter what it is - leaves. It would best be built in by the harness manufacturers.

But hang gliding puts all of its spare bucks into parachutes. And I've known a lot more people smashed up by crappy releases than saved by good parachutes. And - although the individual pilots can make sure they're stowed properly - I have no doubt that a lot more people are significantly injured by accidental deployments than saved by deliberate ones.

But anyway...

I think platform launching is so safe anyway that it's acceptable to fly with with most conventional releases - three string, Koch - that require a hand to come off the basetube. Heavy tension at launch and - even if you step right into a dust devil - you're getting blasted into the air so fast that there's not much that can happen to you in that super critical first hundred feet.

Your biggest threat in platform isn't not being able to come off tow - it's not being able to stay on.

Idiots who advise and allow the lanyard to go on the wrist - like Steve Wendt - should be stood up in front of a wall. That configuration killed two young pilots in short order in 1990 and nothing was done about it.

Idiots who deliberately advise configurations which auto release at high pitch attitudes to protect against lockouts - like Peter Birren - should be shot two or three times to make sure.

The other deadly problem you don't wanna have is the goddam weak link blowing. I'd advise six hundred pounds - one-size-fits-all. (That's one thing the Houston guys seem to be doing right.)

If I were gonna platform tow tomorrow I'd use a pair of barrel releases:

http://www.flickr.com/photos/aerotowrelease/3313497455/

The proportions would hafta be altered. You need the barrels close to the tow loops so you can reach them when they're pulled straight back and the Bridle Link between them would need to be elongated to compensate and yield sufficient overall length.

The Mason Release in Zack's photo ain't bad. I haven't tested it to six hundred pounds but it did real well at near four.

But he's obviously using Perlon (nylon) for everything and that's got no place around tow equipment. Should be replaced with Dacron or some other low stretch material.

And there should be a tow ring or thimble in the loop at the end of the tow line to keep form abrading the weak link.

Also...

What Donnell and Peter Birren never seemed to have figured out is that the best release mechanism in the world can be totally useless if you can't actuate it when you need to.

http://www.flickr.com/photos/aerotowrelease/2337501636/

If you're gonna use a three-string, rig it so you can actuate it with either hand without having to look for anything within about a second of making the decision.

Also...

Anchor the bridle at the tow loops. This business of routing around the pilot and going to the carabiner "to take the stress off the harness" is a bunch of crap. If you've got a harness that's gonna be feeling any pain with an extra six hundred pounds on it give it to Davis or Jack.
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Re: missing release

Postby TadEareckson » Sat May 14, 2011 10:29 pm

Bob,

Re: missing release
bobk
2011/05/13 13:13:54 UTC

Cutting it a bit close aren't you? 41 seconds earlier and you coulda brought the apocalypse down on all of our heads.

Since your current browser has trouble uploading images, I've taken the liberty of posting them here.

I can do 'em anywhere just by logging on with the other Mac - just thought I'd save the bandwidth. But, what the hell, as long as you've got them up and side by side...

I REALLY like the twin barrels over the three-string.

The ONLY advantage that the three-string configuration has is that there's ZERO possibility of a bridle wrap 'cause the release is upwind of the bridle.

1. But if you put releases on bridle ends you double their capacities ('cause they're only feeling (a bit more than) half the towline tension).

2. Even with only half the load on one a barrel release kicks a three-string's a** with respect to slack line performance.

3. With proper design, the bridle wrap issue is virtually zero - and you've got another release to deal with it anyway.

4. There are, for all practical purposes, zero abrasion/wear issues associated with towing and actuation.

5. The mechanisms are simpler and cheaper.

6. The load is always distributed equally between the two anchor points (tow loops on the harness). (With that three string configuration you could get the full load going to just one tow loop through just one bridle half.)

Zack,

I don't know and I don't know if anyone does.

I'm kinda surprised and disappointed.

I'd love to know what the actual tensions are (not just at launch but through the whole tow)...

1. Get Sam to bring his 200 pound scale next time - if you don't have one.

2. Tie it to a trailer hitch and simulate a launch.

3. I think you can get pretty close to what's going on at altitude just by doing the math for the reduced spool diameter and throwing a few more pounds in to account for the line that's being lifted.

...though I don't think it's all that important in the end.

1. The flight park a**holes have gotten off a few zillion tows having no freakin' clue what the tension of the line is. Likewise with respect to the strength of their (our) weak links.

2. I asked Sunny what the towline tension was, he told me he was tired of not being able to answer that question and asked me to get some numbers.

I rigged a cylinder and got some numbers for me on my HPAT 158 (320 pounds, VG on) behind a 914 Dragonfly - vanilla and turbocharger kicked in (125 and 155 pounds). But for the last couple years before the sonsabitches kicked me out they could never be bothered to let me go up four hundred feet on a tandem to get another really useful data point. With those weight, glide ratio, and climb rate numbers I coulda made some pretty good predictions for other gliders.

Michael Derry - 2001/10/02

The climb rate for the 914 is mind blowing !!!!!!!! I wonder how much extra tension is pulling the hang glider say in KG's?

Tracy Tillman - 2001/10/02

I don't know--there is some.

Stupid useless bastards.

(And instead we gotta deliberately release from the bottom and jam the bridle to see what happens to a Falcon when you tow it from the keel.)

No one suggested it could cause a decrease.

It's confusing 'cause TO COMPENSATE for the line drag and what it's doing to the glider you've gotta INCREASE the tension at the truck.

I'm having a hard time wrapping my brain around this.

Me too. Try this...

Choo-choo train. Locomotive, a thousand horsepower, a hundred empty boxcars, a caboose, a hundred miles of straight track in Kansas, no wind.

Most of what the engine is working against is the aerodynamic drag of each and every boxcar - and the caboose.

There's a zillion pounds of loading on the coupling between the engine and the first boxcar. But at (call it) twenty miles per hour you could probably hold the caboose to the last boxcar yourself without being torn in half.

That's essentially what's going on with the drag and tension with respect to the towline. It just gets confusing 'cause the towline drag is so negligible compared to that big min sink / high angle of attack drag generating caboose you're trying to move up a two thousand foot mountain with ever increasing train length.

In the end I think it's a bit academic since other factors appear to affect tension a lot more.

It's hugely academic. But knowledge is power and that's all you're got going for you against tug drivers.

Be that as it may, there is a wealth of excellent information on this thread. Thanks.

Delighted. But if you need a little entertainment to break up the tedium check out the Julia Kucherenko thread. They totally skipped releases and wheels and are now discussing the best ways to administer CPR. Somebody please let Bill Bryden know about it.

Sam,

I think the line that failed on my release is the same size as your last loop that engages the tow line on Zack's release.

Me too. Which would make it 205 leechline.

I'm thinking that two knots came untied with the increased forces/tension.

I'm thinking that that's about the looniest configuration anyone's concocted in a very long time.

1. You can't get to it when you need to.

2. The bridle is high stretch.

3. It uses an unbent bent pin.

4. When you blow - or lose - the weak link you lose the release.

5. The weak link is half as strong as it should be so you're pretty much guaranteed to lose the release. (So he can sell lots of them?)

6. The weak link is a U which appears to be tied to the bridle apex with two Bowlines. It should be a loop formed with a Fisherman's Knot. Bowlines are OK as long as they're under uninterrupted loads - otherwise they're a real bad idea. People die when things connecting gliders to winches come undone.

7. There's a length of leechline connecting the release to the bridle (in addition to the weak link) which, as far as I can tell, serves no function whatsoever. It just blows after (or possibly before) the weak link does.

Reconfigure your remaining release so's it looks like Zack's.

On -windy- days while on tow, the rope is at ~45* angle.

The rope and glider can't differentiate (head)wind from truck and winch generated no wind airspeed. If the winch is turning the same RPMs (read the truck is maintaining the same airspeed) the angle's gonna be the same.

When the vehicle slows or even stops, and you are still climbing, flight path has to be in an arc.

You can't predict what the flight path of a climbing glider's gonna be with a payout winch. It can be an arc curving forward or aft, a straight line straight up or angled forward or aft, or just about anything else the driver, pilot, and wind wanna make it.

At the top of the tow/arc, if the spool is not turning, and you are still climbing, at some point you will be climbing/flying farther away from the vehicle/winch. Like going into orbit.

No. As long as the spool is stopped (and the line is tight) you're in static tow mode and there is absolutely nothing you can do to change your distance from the vehicle. If you're lined up and climbing you WILL be describing an arc - relative to the vehicle.

That would cause a spike in line tension.

No, the tension's not gonna spike unless unless there's something going on with the gas pedal, basetube, gradient, or thermal activity.

But then why won't the winch spool out?

You know you've got drum inertia combined with the issue of the rotor being harder to break away from the brake pressure than keep turning under the brake pressure.

Thanks

And thanks for participating.
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Re: missing release

Postby TadEareckson » Fri May 20, 2011 5:01 pm

Sam,

Yes, I'm gonna replace the 205, and tie at bridle with one knot.

If that means what I think it does you're again gonna have a potentially dangerously light weak link - same strength - and should expect to lose your last three-string before too many more tows.

Again, I'm recommending that you connect the release directly to the bridle and configure the weak link as Zack has in his photo in my 2011/05/08 post.

Just did some tests on a couple of flavors of weak link material a couple of days ago...

http://kitestrings.prophpbb.com/post390.html#p389

I would predict that Zack's three string configuration would blow pretty close to five hundred pounds.

~45* tow line angle is optimum.

No. Zero degrees towline angle is optimum. You're gonna get your best feet per minute per pound tension when the glider's level with whatever's pulling it - Dragonfly, winch, boat, truck.

And, of course, for the latter three that's only gonna happen at launch and shortly thereafter.

And, of course, you're not gonna get that at all for platform launching.

This doesn't happen if you are pulled in.

You can't predict the angle during a payout tow based upon pull-in.

If the driver floors it after the glider launches the angle's gonna stay relatively low as a lot of line pays out and the truck leaves the glider behind.

And as he slows and/or cranks up the tension the angle's gonna increase.

Barring a gradient, with the truck and glider maintaining the same groundspeed and the glider maxing out its climb, the tow angle for a good double surface glider is gonna be about seventy degrees - the better the glide ratio the higher the angle.

On a surface tow your climb is generally limited by available runway and it's maxed by flying min sink.

At best glide with constant tension you'll have the highest angle - but not altitude - over the truck.

For aerotow, in which limited runway isn't an issue, you get highest fastest at best glide - tug speed permitting. But you don't have any pitch options 'cause the tug's calling all the shots - you put the bar where you need to to keep him on the horizon.

Yes, I did exit the arc and increase the distance from the vehicle.

At the top of the tow/arc, if the spool is not turning, and you are still climbing, at some point you will be climbing/flying farther away from the vehicle/winch.

If the spool wasn't turning you weren't exiting any arcs or increasing any distances from the vehicle (beyond maybe pulling a bit of sag and bow out of the line).

Where did the tow force come from that broke the weaklink?

Like Zack said, breezy days.

1. That weak link - in keeping with Skyting, Towing Aloft, and USHGA voodoo aviation - was marginal to begin with.

2. The ever decreasing diameter of the spool with constant brake pressure is a BIG issue (and you're always combining that with extra line weight).

3. Gusts and thermals are gonna translate to drum inertia issues.

4. If the drum is hovering around stopped you're gonna have BIG braking issues.

5. A steady or gradually increasing breeze is gonna have ZERO bearing.

Zack,

I'm having a hard time wrapping my brain around this. I don't have a very intuitive grasp of physics (probably why I suck at engineering).

Thanks Tad, the train analogy makes a lot more sense to me.

It gets a lot easier when you simplify and model using extremes.
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Re: missing release

Postby TadEareckson » Sun Jun 26, 2011 10:54 am

Sam Kellner - 2011/05/19

Yes, I'm gonna replace the 205, and tie at bridle with one knot.

Tad Eareckson - 2011/05/21

If that means what I think it does you're again gonna have a potentially dangerously light weak link - same strength - and should expect to lose your last three-string before too many more tows.

Again, I'm recommending that you connect the release directly to the bridle and configure the weak link as Zack has in his photo in my 2011/05/08 post.

Just did some tests on a couple of flavors of weak link material a couple of days ago...

http://kitestrings.prophpbb.com/post390.html#p389

I would predict that Zack's three string configuration would blow pretty close to five hundred pounds.

Al Hernandez - 2011/06/25

Leakey, Tx and Pack Saddle

Martin and I, arrived at Leakey at 10:45 am, the sky was a blue color, with few disappearing clouds in the area, winds 8mph to 14mph and not too much lift on Friday. Our intentions were to have fun on the Leakey payout winch and give it a test run and to our surprise the winch worked as we expected to. As we arrived Sam Kellner was the first up climbed to about 800 ft, flew around for a bit and came in and land it... Another pilot went up on a Genesis Pac Air Glider and had an okay flight, came in for a wheel landing on the grass.


Martin Apopot on his first flight got up to about 700 ft sled run, flying a falcon 145 single surface glider, good flight & safe landing.

Martin A. had two 800 ft sled runs after that.

On one of his not counted flight, Martin broke a weaklink at low altitude, causing an 80 ft free flight on his glider, the right wing was up, and flew way off to the right side of the runway, the glider flew over the airport fence, over the trees and house, for a little while, He managed to get his Falcon in control and landed safely back on runway... WHAT A RUSH ! what can I say S#it Happens.

We said good bye to Sam and the crew and Martin and I, headed out to Pack Saddle, Martin got 2:15 of air time and got up 2064 on first launch, During the landing had a bad flair and belly landing, broke left down tube on his falcon 145... no injuries.


Thanks to everyone in Leakey, Tx for a over all good time and safe flying.

Dave Broyles - 1990/11
Allen, Texas

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

Hi Sam,

Next time you see Al and/or Martin maybe you could relay...

1. Shitt happens MUCH less frequently to people who:

a) fly with 500 instead of 200 pound weak links;
b) fly with eight inch pneumatic instead of barely-visible-in-the-video placebo wheels;
c) don't use hang checks to confirm hook-in status;
d) don't think that people get put out of control, crashed, hurt, and killed in aviation as consequence of shitt happening.

2. Marijuana is a MUCH healthier way to get a rush than blowing a half G weak link at eighty feet in a right roll and doing a circuit over a fence, trees, and a house before getting a Falcon 145 back under enough control to return to the runway. (A reasonably good argument can also be made for crystal meth.)

3. Although not counting as flights anything that doesn't make it to two hundred feet is a TOTALLY EXCELLENT strategy for improving tow crash, injury, and fatality statistics, the television stations and newspapers tend to count them as flights anyway.

4. You're gonna break a LOT fewer downtubes (and arms (and necks)) doing intentional belly landings than you are attempting to do good flares. (Compare/contrast recent data for Genesis Pac Air Glider and Falcon 145 guys.)

5. And maybe tell Al that he might wanna tighten up his concept of "safe flying" to something narrower than nobody-got- creamed-today, ALTHOUGH... He's WAY ahead of Jerry Forburger - who considers three totaled gliders and two injured and one dead competitors over three days of tasks to constitute "a safe tow meet". At this rate I'm pretty optimistic about where we're gonna be in ANOTHER twenty years.

Thanks much,
Tad
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Re: missing release

Postby TadEareckson » Mon Jun 27, 2011 1:07 pm

Lotsa times when I quote somebody who's made something of an effort I'll help him out by fixing a typo or two, but when it's a post that the author hasn't bothered to think about or read before clicking "Submit"... Sometimes that in itself is useful information.

Anyway, Al originally posted on The Davis Show at:

2011/06/25 06:01:41 (UTC)

and had gotten through a third edit by:

2011/06/26 20:16:09

And he also had a duplicate up on The Jack Show titled:

Martin Fly's Leakey and Pack Saddle on Friday

at:

2011/06/26 14:45

So let's look at the modifications...

Not a fix, just a reference to the clip after the video was uploaded:

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

Again, you can't tell whether or not Martin is doing a hook-in check but, given his history, I think the fact that there's nothing very clearly documenting that he IS is pretty good evidence that he ISN'T. Not quite as solid as a fatality report, but the season is far from over - especially at that latitude.

And it's always fun to watch somebody folding a downtube and/or ripping a shoulder apart in a wide open flat field practicing to land safely in a narrow dry river bed with large rocks strewn all over the place or a field filled with seven foot high corn.

And I'm absolutely devastated that we didn't get to see the S#it Happens flight. Didn't have the camera running? Maybe a bit too upsetting for the kiddies?

OK, on the the text...

Before:

...the right wing was up, and flew way off to the right side of the runway...

After:

...the left wing was up, flew off to the right side of the runway...

Yeah, you didn't hafta be a rocket scientist to figure out that something was seriously wrong with the first draft.

Before:

WHAT A RUSH ! what can I say S#it Happens.

After:

WHAT A RUSH ! what can I say S#it Happens. Good maneuvering skills Martin.

I find the revision a bit confusing...

He managed to get his Falcon in control...

1. He's out of control most of the time - but demonstrating good maneuvering skills?

2. He's out of control maybe one and a half wingspans over a house off the side of the runway? Does that get you some kind of USHGA or FAA airmanship award?

3. I was under the impression that the flight plan was to climb to eight hundred feet or so behind the truck and stay up for as long as possible. Wouldn't THAT have been considered superior maneuvering?

Before:

Thanks to everyone in Leakey, Tx for a over all good time and safe flying.

After:

Thanks to everyone in Leakey, TX for letting us test your winch

Yeah Al, maybe upon further reflection...

SO... Anybody got any ideas here? I'm open to just about anything.
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Re: Truck towing accident in south Texas

Postby TadEareckson » Tue Jul 05, 2011 2:24 pm

Nestle Shane - 2010/10/18

I'm with Jeffo. He sold him a glider in April. The pilot was getting instruction from Hewett. Don't know where the tow rig and release came from.

Jeffo told him he was available for whatever instruction he needed.

Jeffo being Jeff Hunt.

But let's understand that Lemmy isn't one tiny bit deader than anyone on a very long list I can put together of extremely experienced tow pilots with most or all of the relevant merit badges - including instructors, tow park operators, and appointed rating officials.

And let's also understand that extremely dangerous shitt happens at altitude so often that people don't even think it's worth mentioning - let alone officially reporting or fixing - because our standards and expectations are so shoddy that it's just considered normal background noise.

Lauren Tjaden - 2008/03/23

When Jim got me locked out to the right, I couldn't keep the pitch of the glider with one hand for more than a second (the pressure was a zillion pounds, more or less), but the F'ing release slid around when I tried to hit it. The barrel release wouldn't work because we had too much pressure on it.

Anyhow, the tandem can indeed perform big wingovers, as I demonstrated when I finally got separated from the tug.

For the purpose of that training exercise while Lauren was getting her tandem rating at Quest - which she and Paul now run - she and her passenger got killed about five times over. But it happened up high - like it ALMOST ALWAYS DOES - so who gives a rat's a**?

I'd say the vast majority of people in this sport really shouldn't be trusted with gliders - or, more importantly, passengers or students.

And I'm not so much concerned that this guy was armed with a glider and a winch as I am with the fact that - even if the conditions were a bit on the hostile side that evening - he'd have been in WAY better shape to deal with them if he had platform or dolly launched and/or been able to release with BOTH HANDS on the basetube.

But the concepts of rolling launches and using two hands to fly a glider close to the ground when it's roll stability compromised aren't elements of the Skyting Criteria for safe towing 'cause there wasn't room for them after we got through with:

Constant Direction
Constant Tension
Center Of Mass Distribution
Center Of Mass Attachments
Gradual Transitions
Infallible Weak Link
Reliable Communications

so they never made it to the list.

I've got a thousand bucks - which I don't hafta risk because we don't have a time machine - that says that if we had just platform launched him or put him on a dolly with a release actuator on the basetube he'd have his Hang Three by now.
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Re: SWTHG club winch

Postby TadEareckson » Tue Jul 05, 2011 2:51 pm

Towing Aloft

A certain amount of stretch is absolutely required with this system to absorb and dampen tension variations.

The stretch is necessary and desired to moderate fluctuations when thermals or gusts are encountered.

Just make sure you NEVER use it for static towing and ALWAYS have the drum turning or you'll instantly pull the glider out of control and/or rip it to shreds.

And use an extra light weak link just to be extra safe.
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Re: SWTHG club winch

Postby TadEareckson » Wed Jul 06, 2011 6:03 am

What was wrong with Bill Bennett's release system...

Nothing. In the Seventies the RELEASE systems tended to be really excellent.

...it appears that this system would let you escape a lockout fast without moving your hands form the uprights or bass bar.

The problem was that the BRIDLE systems also PUT YOU INTO lockouts fast - even without moving your hands from the uprights or basetube.

When originally people intuitively connected to the control frame... The good news was that this made it extremely easy to design and build good release systems which were actuated by a lever or two in hand position(s) on the basetube. The bad news was that the "pilot" was pretty much a passenger on a plane with zilch pitch and roll control (for hang gliding that pretty much covers all the bases) and a high tendency to lock out hard and fast when things got out of line a bit.

Then at about the same time - 1980ish - Mike Lake's crowd in the East England and Donnell Hewett in South Texas figured out that tension needed to come off the control frame and route through the pilot and hang point. The East Anglia guys developed practical stuff that worked, Donnell came up with a bunch of bogus assumptions and botched physics models and instituted a lot of very dangerous equipment and procedures.

Donnell put a lot of effort into publicizing his approach through a newsletter that circulated worldwide and established the rotten crooked foundation of modern towing and buried the superior approach from the UK - even in the country of origin, where it was was written out of the history books - at the cost of many lives.

Practical aerotowing and platform launching was still a bit over the horizon so everything was surface based - winch, truck, boat - and dollies, though in use at least by 1983, were slow to catch on. We had the aquatic equivalent of dollies with pontoons, but everything else was foot launched.

So now everybody's starting on the downtubes and shifting to the basetube at the most dangerous time of the tow. And the tow angle is going from zero to sixty or seventy degrees as the glider climbs and tops out. And now it's not so easy to configure releases and deal with the problem of interference with the basetube.

What I do see, it may make steering the glider a little harder and not having too much pitch control while on tow...

No, it was one hundred percent totally unacceptable. ALTHOUGH... Given a choice between a mid Seventies system and the original Skyting Bridle, complete with the Infallible Weak Link...

...and maybe that is why pilots decided to tow under the bass bar and not from the front of the glider...

Under or over is just a matter of tow angle. Aero is constantly zero or thereabouts and the bridle is over, platform is constantly high and the bridle is under, and in other surface it starts out low and finishes high and you've got a problem.

Donnell "addressed" it by limiting the climb with the bridle over or accepting interference at launch and early in the tow with it under. Incredibly, people are still doing it that way.

http://www.youtube.com/watch?v=SGPZkrf94D4

http://www.youtube.com/watch?v=H7CP-hk9ZZE

Mike was the first person to start really addressing the problem with a couple of designs but the Koch two stage - 1985 or maybe a bit earlier - which allowed the pilot to shift from totally over to totally under at his discretion made them obsolete.

...this unit is almost the same system for aero towing...

In 1991 with dolly launched two point aerotowing on the Dragonfly we originally had a very safe system. But immediately afterwards the warped minds in Florida came up with the Wallaby Release - one of the worst things that ever happened to hang gliding - which employed a velcroed on bicycle brake lever and moved the actuation point from the basetube to the downtube. Yeah, on some gliders it can still be crammed onto the basetube but usually isn't. And it tends not to work a lot of the time no matter where you put it.

...if it could be re-modified, somehow to work for platform towing...

It's very easy to engineer - safely, cleanly, cheaply - for aero. But not for surface. If you're willing to accept a lot of crap in the airflow you can run cable from the basetube to the bridle apex. I'm not.

To do it right I think the best approach is to run a wire down your sleeve to blow the bridle assembly away in an emergency via solenoids at your hips. But that will never happen for two reasons:

1. It's expensive and would hafta be built in by the harness manufacturers.

2. Platform launching is so safe and risk manageable that we wouldn't get any appreciable bang for our buck.

I have read of pilots crashing because, they were hanging on for dear life and did not reach-out to the main release for whatever reason they experienced during their last moments...

The reason is often because it won't make any difference in the outcome.

If he doesn't let go to release the lockout will continue to progress and he will die on tow.

If he does let go to release the lockout will immediately and rapidly accelerate and he will die right after he gets off tow.

(Or - if he wants to REALLY accelerate the lookout (and multiply the required recovery altitude by a factor of ten) - he can follow the advice of some total moron like Jim Rooney and push out to blow the weak link.)

Also... Even if you are equipped to release the instant you can react with no compromise in control - the situation may not be survivable. Similarly you can launch off of a ramp on the mountain into something that isn't survivable. That's why we need to be watching ribbons just before launch in both environments.

So...

I have read of pilots crashing because, they were hanging on for dear life and did not reach-out to the main release for whatever reason they experienced during their last moments...

Please don't ever say anything like that again. A fair statement would be:

I have read of pilots crashing because they were hanging on for dear life and COULD not reach the main release during their last moments because the incompetent criminally negligent bastards who run the flight parks equipped them with garbage which they KNEW in no uncertain terms would be inaccessible in an emergency.

The way you phrased it plays too much into the hang gliding establishment's "Blame The Dead Guy For As Much As Possible" safety strategy.

Doug Hildreth - 1991/06

Pilot with some tow experience was towing on a new glider which was a little small for him. Good launch, but at about fifty feet the glider nosed up, stalled, and the pilot released by letting go of the basetube with right hand. Glider did a wingover to the left and crashed into a field next to the tow road. Amazingly, there were minimal injuries.

Comment: This scenario has been reported numerous times. Obviously, the primary problem is the lack of pilot skill and experience in avoiding low-level, post-launch, nose-high stalls. The emphasis by countless reporters that the pilot lets go of the glider with his right hand to activate the release seems to indicate that we need a better hands-on way to release.

I know, I know, "If they would just do it right. Our current system is really okay." I'm just telling you what's going on in the real world. They are not doing it right and it's up to us to fix the problem.

"Us" never fixed the problem. What us did was make sure that the stuff that "we" did that fixed the problem would never get into circulation on any significant scale. May us rot in hell for all eternity - and preferably start doing it soon.

I have been trying to find out how this works...

Lemme save a little bandwidth and refer you to:

http://kitestrings.prophpbb.com/post461.html#p461

in which I was recently walking miguel through things.

It does have a lot of lines on it and pullies too, how would that go on a hang glier?

It doesn't GO ON the glider - it's BUILT INTO the glider... Just like they do in REAL aviation (read: sailplanes) instead of this chickenshit branch in which we're stuck.

http://www.youtube.com/watch?v=MiIjhn4YoIE

Yeah, look at all that crap flopping around in the airflow. That's the best we can do after near over a quarter century of aerotowing?
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Re: missing release

Postby TadEareckson » Wed Jul 06, 2011 1:18 pm

Oops, primarily because of the old machine and browser I use most of the time, I didn't notice your post here until just now. Sorry for my delay in responding.

Like it has happen to you as well Tad.

Not sure what you mean by that but to be clear...

I have been crashed and/or hurt for the following reasons:

a) my own carelessness;
b) crappy instruction;
c) crappy tow operators.

And I had a really dangerous control issue with a really dangerous Wills Wing Harrier 177 with a design flaw which could have very easily have killed me if I had been a bit lower at the time.

None of that falls under the "shitt happening" heading.

So you can only imagine as you always do...

I can and do do a lot better than that. I can watch videos, read, look at past histories, listen to what people are and aren't saying, do the math... Sometimes I can figure out from three hundred miles away and over a decade after the fact what happened in a double (tandem) fatality a thousand times better than a whole flock of eyewitnesses ever can or will be able to.

...if he did a hang check or not.

The issue isn't about hang checks. The hang check is one of the worst two or three idiot ideas ever to come out of hang gliding. People who do hang checks - like Martin - are about ten thousand times more likely to launch unhooked than people who don't - like Rob Kells.

You are never there Tad.

I wasn't on the Challenger or the Columbia either - but I've probably got a better understanding of what went wrong and why than the people who were ever did.

The only ones that get the most flight in this area is Zack and Martin.

Which is relevant to anything how?

Flying imresses me very little - often much less. There are untold thousand of extraordinarily stupid people who do it extraordinarily well. And not a one of them will ever hold a candle to a Turkey Vulture or Barn Swallow. And not a fraction of a percent of them will leave the sport better than it was when they had it handed to them.

Still Like you anyway Tad...

I like you too, Al. I think you've got a good attitude. Maybe enough of it will rub off on Martin so that I'll be able to help him recover from his Lookout training and boost his long term survival odds a bit.
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Re: Truck towing accident in south Texas

Postby TadEareckson » Wed Jul 06, 2011 10:42 pm

Oops. Got diverted and distracted. Forgot about this one.

Makes you wonder on what part of the base bar she was putting her hand on, it suppose to go to the center, while the other hand plays with the strings...

1. Subsequent to the introduction of the practice of towing through the pilot and to the hang point I have personally known one pilot each injured and half, three quarters, and totally killed in low level lockouts.

2. Name another flavor of aircraft that's as dangerously roll unstable as a hang glider on tow.

3. Name one other vehicle - chariot, bicycle, Segue, motorcycle, ATV, snowmobile, Volvo, Lamborghini, tank, sailboat, Boston Whaler, submarine, battleship, hovercraft, sailplane, Cessna, 747, F-16, space shuttle - that requires you to compromise or surrender steering authority to deal with an emergency.

4. I somehow missed the training in which you're told that you can maintain safe or adequate control of a locking out hang glider by moving one hand to the center of the basetube while groping around for something for a while with the other.

5. In real life...

Peter Birren - 2008/10/27

Imagine if you will, just coming off the cart and center punching a thermal which takes you instantly straight up while the tug is still on the ground. Know what happens? VERY high towline forces and an over-the-top lockout. You'll have both hands on the basetube pulling it well past your knees but the glider doesn't come down and still the weaklink doesn't break (.8G). So you pull whatever release you have but the one hand still on the basetube isn't enough to hold the nose down and you pop up and over into an unplanned semi-loop. Been there, done that... at maybe 200 feet agl.

6. Yes, you DO want stuff like that - but lower - happening to a**holes like Peter, but every once in a while you meet someone in hang gliding you want to stay in the gene pool a bit longer.

7. Me? I have enough trouble not flying into windsocks, hangars, trees, ponds, and runways with both hands in the usual positions on the basetube even when I'm OFF tow and nothing much is going on.

Regardless, she or he was scared sh#tless and was hanging on for life...

Nah. She wasn't scared shitless. 'Cause she was on a simulation WAAAY up high. And since she was initially trained at Ridgely she's used to tow equipment failing every third or forth flight. And neither she nor any of her pin-brained flight park friends can conceive of what would have happened in this scenario in a real emergency at a hundred feet. As long as she blends right in with the in crowd she's happy as a lark.

8. 'Cept every now and then when one of the in crowd ends up in the emergency room, shock trauma unit, or morgue.

Lauren Tjaden

2005/10/02

I am too upset to be politically correct. What the hell is this? I mean, do you have to be my friend before you die? I don't want to know you if you are going to go away. I mean, I really don't. Be some faceless nobody who I don't care about. The list of friends you have that have died hang gliding is, at some point, like the guys you have slept with. It's bad to count.

I guess I am making progress. I couldn't even talk about Chad in the past tense for maybe a year and a half after he died. Yeah, this is good. I am getting lots more used to this shitt. You pile it in and I will be over you soon.

2006/02/21

Yes, the Jim in the article is OUR Jim, Jim Rooney. This is a difficult time as many of us love Jim very much, and I know you are all anxious for news, as we are.

I am sure that the link knife didn't come to mind...

1. Lemme show you just how effective a hook knife is half a mile up in smooth air with low controlled tension and the glider stable and under control:

http://www.youtube.com/watch?v=mJGUJO5BjnA

2. What kind of shape do you think those two planes would have been in forty-three seconds into a lockout?

3. What kind of shape do you think those two planes would have been forty-three seconds into a lockout that started at a hundred feet?

4. What do you think would happen to the glider if Lauren had managed to hack through her secondary bridle and the bottom end of the primary had tied itself to the tow ring - like her dear friend Jim Rooney says happens with the top end over half the time in lockout training?

5. Would you board a flight to Honolulu if you thought there would be a high probability that you'd be wishing you had paid more attention to the instructions about oxygen masks and the use of your seat cushion as a flotation device?

6. Would you not board a flight to Honolulu if you were informed that the seat cushions were a bit old and no longer floated very well?

7. Why are we talking about hook knives and not why we're flying with mission critical equipment that some asshole thought would be OK to velcro to the downtube and make out of whatever bent scrap metal he had lying around the shop?

8. Let me reiterate -

SHE HAD TOTAL FAILURES OF BOTH HER PRIMARY AND SECONDARY RELEASES IN A CONTROLLED EMERGENCY SIMULATION.

AND WE'RE TALKING ABOUT fu**ing HOOK KNIVES???

9. There. I feel a little better now.

...why didn't the weaklike brake?

1. Perhaps because they were at altitude and the weak link thus understood that there was no imminent threat to the safety of Lauren and Dustin. Had they been below two hundred feet however the weak link would have undoubtedly realized the gravity of the situation and blown at the first sign of trouble - just like it says it will on Wallaby's website.

2. Why SHOULD the weak link have broken? A couple of summers ago Roy Messing's weak link didn't break before he was beyond the point of no return in a fatal lookout (which Whitewater described as "mild") and nobody was questioning ITS performance and sense of duty.

That is what it is for maybe too strong of a weaklink...

1. What strength do you recommend? There's a lot of controversy about what's best for lockout prevention and we need all the opinions we can get so we can arrive at a fair and solid democratic solution.

2. Was the weak link on the tug also too strong?

3. What strength do you recommend for the tug end?

4. Do you really have any idea whatsoever what a weak link is for?

...why didn't the tug pilot gave the HG pilot the line right away...

1. Why should that be the tug driver's job?

2. What happens if the tug driver makes the wrong call? Is it possible for people on gliders to get creamed or killed when the tug's release is squeezed or its weak link blows?

3. In low level emergencies when it IS critical that the tow be aborted immediately tugs have real lousy records of intervening fast enough to keep people alive and healthy.

4. I was kinda hoping they'd be able to stay on long enough for Lauren to get that bent pin release on her shoulder pried open. You can some really spectacular reports about broken tumbling gliders and deployment attempts in some of those scenarios. And if you're really lucky somebody gets in on video.

Don't like Tug-towing anyway I'll stick to payout...

I LOVE tug towing. Well, I would have loved it if hadn't been implemented by the total morons we got. As it is I despise it.

Platform - despite the fact that there's no existing good way to configure the release for both hands on the basetube actuation - is a lot safer. You blast up through the kill zone real fast, the tension is constant and controlled, there are no a**holes to mandate your weak link rating or override your decision with something on the other end, the driver couldn't kill you if he tried, and the driver doesn't hafta be and frequently isn't a pilot so you're a lot more likely to get someone with a brain managing the other end.

But...

...thermals are everywhere...

Lucky you. That hasn't always been the experience of everybody in this neck of the woods.

...much rather work my way up...

1. EVERYBODY would rather work his way up. If I could work my way up every time after launching off a hangar roof I'd do it. But around here people tend not to have much luck when they start from below a grand.

2. And there aren't a lot of tow strips around here long enough to get gliders up to a grand in light air.

3. If there's a rule that one can't release from a Dragonfly in lift from under a thousand feet I wasn't informed.

4. Actually, now that I think about it a little more... I hate ALL forms of towing. They're all just necessary evils to get me up to levels at which I can start fending for myself. But I hate them a lot less than spending hours on the road to the mountains and finding out that the wind is too strong / light / cross and having only one shot at finding something per setup / breakdown / shuttle cycle.
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