Releases

General discussion about the sport of hang gliding
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Tad Eareckson
Posts: 9161
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Re: Releases

Post by Tad Eareckson »

Actually it would've looked more like:

http://www.flickr.com/photos/aerotowrelease/8306258400/
Image
Hugh McElrath - 2009/03/18

Re: second channel

Sorry I didn't reply immediately. I am caucusing with the BoD. Let me just say that I don't think you were the only sinner on the forum - others sort of ganged up on you and backed you into a corner. We are working on a formula whereby you promise to be good, use no language that a reasonable man might consider to be "fightin' words" (this goes considerably beyond George Carlin's seven words you can't say on television), KEEP YOUR POSTS SHORTER, and stay in whatever "aerotow release technical discussions" topic gets established (for posts about that topic). I also plan to say something to the general audience about decorum and not ganging up on someone that has a unique viewpoint. If that makes the forum less interesting, so be it. Gimme a couple more days to operate - as you may have seen, we just lost Matthew and Karen from the board and need to elect new officers. - Hugh

P.S. I still have and am willing to pay for the one- and two-point releases you made for me. I still need more edumacation about how to set them up - the single briefing you gave me in the parking lot in Bowie has faded. Not sure whether I will be out at Ridgely Saturday (kid has an event). I have already moved on to the sailplane club in Front Royal (working on both glider license and getting qualified to fly the tow planes), but I'm still in the hang- and paragliding games (I presume you can see posts but not write to the forum - check out my "blog" on my and Ellis' PG trip to New Zealand for a maneuvers course.).
Part of the stuff he never quite got around to paying me a dime for - while he was also never quite getting around to doing shit about plugging me back in when my "three month" "suspension" was over.

Hugh, the Capitol Crowd, the Highland crew can rot in hell.

P.S. And now we've just lost Matthew and Karen from a lot more than just the board.
P.P.S. Thanks for getting it.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=47096
Aerotow Primary Release
Rich Diamond - 2016/03/30 14:16:12 UTC

I use the " Gettoff Tow " Release.
Good Rich. Now see if you can learn to spel it.
very pleased with it .
Great! The semiliterate dickhead who first called for my extrajudicial banning from the Houston club...

http://groups.yahoo.com/group/hhpa/message/11545
Question
Rich Diamond - 2010/11/06 15:38:46 UTC

Zack (mr moderator)
its replies like this from TADpole that We should not have to put up with his crapola anymore.
At the meeting or Now on line , i wish to Call for Vote by its HHPA members to Ban Tad .
for Ban of Tad = I vote Ban him into the cornield (1)

Rich D Hey Dave S- your a hang one ( Ha ha)
...which was the event that precipitated the founding of Kite Strings is "very pleased" - above all other options with the release which was inspired by my work and in whose development I collaborated extensively.
Release rope is Alwayys in my hand ,
Must be a bit unpleasant when you're jerking yourself or one of your glider buddies off.
and when its time to release, i just move my arm forward Over the Control Bar , thus having control if a wing ever got up, i don't have to take my hand off the bar to hit a bicycle release on the down tube. There is No Looking, its Automatic.
'Specially now that no one's using a weak link which breaks before he can get into too much trouble.
the only problem i had once was the rope needed to be a little longer, so changed it out for longer by few inches!
I totally recommend this release! btw, i fly with 3 pt ,
And count.
...i do NOT Protow.
Why not? I've always heard it's MUCH safer - after you've been taught how to do it properly anyway.
Fuck you anyway, Rich.
Jim Gaar - 2016/03/30 14:57:07 UTC

Would like to try Pro Tow one day
I would like you to try Pro Tow tomorrow. Just make sure that along with it you use the weak link...

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Gaar - 2013/02/13 17:57:05 UTC

Former Flight Park Manager

Because it has the best known and accountable safety record (in my personal books anyway).
...with the best known and accountable safety record (in your personal books anyway).
I have never "pro" towed.
Nobody has.
Always have used the 3 point center of mass release (for aerotow).
Suck my dick.
However, I only use the lanyard style as it's always there to pull without letting go of the control bar.
You can safely let go for a second or two. They don't call it an easy reach for nuthin'.
As a backup I use a barrel release with a second weaklink at my left side chest bridle attachment point.
That's actually three backups. Practice pulling your backup every other tow so's you'll be ready for that inevitable day when your primary release fails - as sooner or later all mechanical things do.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=34229
AT release
piano_man - 2016/04/01 15:16:53 UTC
Georgia

http://www.flickr.com/photos/aerotowrelease/sets/72057594141352219/
Aerotow Release System

Can anyone tell me how and if this thing works?
http://www.flickr.com/photos/aerotowrelease/8318603266/
Image

- Anyone over there on The Jack Show?

Image

- Why would you care? Quest has been involved in perfecting aerotowing for over twenty years...

http://c2.staticflickr.com/2/1523/25679752020_89cc46e0e3_o.jpg
Image

Just get something from them.

05-02713
http://c2.staticflickr.com/2/1639/25711853442_938287954f_o.png
Image
07-03201
http://c2.staticflickr.com/2/1513/25737698641_fdbd9f2aa3_o.png
Image
10-03225
http://c2.staticflickr.com/2/1504/25711850432_5d577ba88c_o.png
Image
20-12126
http://c2.staticflickr.com/2/1493/25532092990_c8f2010dc2_o.png
Image

They've only had a relatively minor issue with it one time...

http://www.flickr.com/photos/aerotowrelease/8318769461/
Image Image
http://www.flickr.com/photos/aerotowrelease/8318781297/
Image

...and they solved it by banning it (at least for a short while) from the Worlds at Hay - and forcing everyone and his dog to use for the next decade a weak link so safe that it breaks six times in a row in light morning conditions. And Bobby's at Quest. And he's a fucking genius when it comes to this shit.

- It OBVIOUSLY doesn't work. If it did, we'd be using it everywhere. But it doesn't stand the test of reality. Just use the release we're all using everywhere. You'll be fine.

- No. It doesn't work. I spent about three billion hours building releases and models, setting up photo shoots, Photoshopping, writing documentation for a system that doesn't work. Dickhead.

- Did you check the forum rules?

http://www.hanggliding.org/wiki/HG_ORG_Mission_Statement
HangGliding.Org Rules and Policies
No posts or links about Bob K, Scott C Wise, Tad Eareckson and related people, or their material. ALL SUCH POSTS WILL BE IMMEDIATELY DELETED. These people are poison to this sport and are permanently banned from this site in every possible way imaginable.
- Have you gotten Jim Keen-Intellect Rooney's take on it?

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

Enjoy your posts, as always, and find your comments solid, based on hundreds of hours / tows of experience and backed up by a keen intellect/knowledge of the issues when it comes to most things in general and hang gliding AT/Towing in particular. Wanted to go on record in case anyone reading wanted to know one persons comments they should give weight to.
He's the one person to whose comments you should give weight. And, obviously, you should take weight away from anyone else's comments. Thou shalt have no other god before Jim.

- If you're actually interested how come you're not talking to the developer? Not bright enough to be able to track him down?
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=34229
AT release
Ryan Voight - 2016/04/01 16:15:08 UTC
Ellenville

Which one? Looks like a collection of images of all different release types...
Just ones that work, Ryan.

http://www.hanggliding.org/viewtopic.php?t=14230
pro tow set-up
Ryan Voight - 2009/11/03 05:24:31 UTC

It works best in a lockout situation... if you're banked away from the tug and have the bar back by your belly button... let it out. Glider will pitch up, break weaklink, and you fly away.

During a "normal" tow you could always turn away from the tug and push out to break the weaklink... but why would you?

Have you never pondered what you would do in a situation where you CAN'T LET GO to release? I'd purposefully break the weaklink, as described above. Instant hands free release Image
Jim Rooney - 2009/11/03 06:16:56 UTC

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

You can tell me till you're blue in the face about situations where it theoretically won't let go or you can drone on and on about how "weaklinks only protect the glider" (which is BS btw)... and I can tell ya... I could give a crap, cuz just pitch out abruptly and that little piece of string doesn't have a chance in hell. Take your theory and shove it... I'm saving my a$$.
05-215
Image
piano_man - 2016/04/01 16:34:04 UTC

It's only part in jest as today is April Fool's Day, but seriously, I've tried to make sense of all those knots and pulleys but always give up.
Big fuckin' surprise. And see note above about contacting the developer.
It seems with todays technology...
...we should be able to put our thoughts into print with grade school level competency in English.
...it would be easy to post a demo of how this or these releases work, e.g, youtube.
You pull the fuckin' string and the fuckin' barrel comes back...

http://www.flickr.com/photos/aerotowrelease/8311348069/
Image
Image
http://www.flickr.com/photos/aerotowrelease/8312399698/

http://www.youtube.com/watch?v=rh3-uZptNw0


...and it fuckin' OPENS.
Just wondering if anyone here has ever seen one of these releases up close, tried 'em, etc.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=233
AT releases
Hugh McElrath - 2005/03/05 17:02:56 UTC

Thanks, Tad. I was too green to fully appreciate your system when you showed it to me a couple of years ago. Now I'm more interested. Do I have to fabricate this myself from parts or are you in business?
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3347
Tad's barrel release tested
Janni Papakrivos - 2008/06/30 15:35:44 UTC

Tad showed me the release system he installed in Hugh's glider. I was amazed at the quality and complexity of the system. Being able to tow and release without ever having to take your hands off the base tube is wonderful and much safer.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=939
Weak link breaks?
Dan Tomlinson - 2005/08/31 00:33:01 UTC

Tad's post is difficult to read but I've seen his work. His release mechanism is elegant in its simplicity and effectiveness.
http://www.hanggliding.org/viewtopic.php?t=12587
weak links (here we go)
Patrick Halfhill - 2009/06/21 23:22:23 UTC

You and I met at the ECC a few years ago. We spent 45 minutes or more together going over your system. I saw it first hand. I was quite impressed with the quality of engineering and the time you spent on it.
Talk to Sunny and Adam. I hear they're not quite as busy as they normally would be about this time of year.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=34229
AT release
Dallas Willis - 2016/04/01 16:50:35 UTC

Search on this forum for that guy...
You'll have to...

http://www.hanggliding.org/viewtopic.php?t=12403
weak link table
ian9toes - 2009/06/14 15:18:37 UTC
Gold Coast, Queensland

I strongly disagree with banning the one guy who has the most knowledge about safety issues involving what I believe is the most dangerous part of our sport. I hear someone dies every year from towing. I hope SG bites his tongue in the interest of public safety.
http://www.hanggliding.org/viewtopic.php?t=11497
Aerotow release options?
John Glime - 2009/04/13 18:09:32 UTC

Rick,

Not being constructive? There is one person who has put more thought and time into releases than anyone. That person is Tad. He explains the pros and cons to every release out there. I gave you the link to more release information than the average person could ever digest, and I didn't get a thank you. Just you bitching that we aren't being constructive. What more could you want? He has created something that is a solution, but no one is using it... apparently you aren't interested either Image So what gives??? What do you want us to tell you? Your concerns echo Tad's concerns, so why not use his system? Every other system out there has known flaws.
Jack doesn't tolerate in his mutual masturbation society anyone who knows what the fuck he's talking about.
...and you'll find where a few of us pleaded with him to put one on an actual glider...
Get fucked, Dallas. There was some form of that release on an actual glider for a decade and a half prior to the brief period during which Jack was assessing my willingness to jerk you guys off.
...and take pics or to send us one to rig ourselves. Never happened.
Get fucked. If I'd developed a revolutionary supersonic stealth jet fighter and made every effort to maintain secrecy about how it works and how it's put together the fuckin' Russians and Chinese would be building knock-offs almost as good in two months and better ones in three. Compare/Contrast... I give assholes the highest quality photographs ever produced of any hang gliding equipment showing every detail in ultra high resolution and give you specs on all the components to the precise millimeter and seven years later you're still paying Davis forty bucks a pop to put a bent parachute pin in a fat little stub of squashed aluminum tubing.

Image

You dumb motherfuckers can't even work as a TEAM to decode the mysteries of the stuff I developed all by my lonesome. (Try getting Paul Hurless to help you. He's totally awesome at designing AT release systems he can't ever be bothered to sketch or describe.)

Meanwhile...

http://www.flickr.com/photos/psucvollibre/
PSUCVOLLIBRE

And he didn't even have the advantage of having the same first language as the developer.

You want pictures, video of something comparable to my release system?

http://vimeo.com/26210217

Image
http://c2.staticflickr.com/2/1698/25936289086_880146dd50_o.png
13-02306

There's Ryan cranking on sail tension for more speed and peformance at the expense of low speed maneuverability. Now go out and design and build a VG system for a T2C. Use the schematics in the owner's manual if you want.
Pretty good joke though Image
Yeah.
Image

A million laughs. 'Specially when you start tallying up all the carnage that wouldn't have happened over the decades with my system or something comparable. Right now I'm hoping you motherfuckers DON'T use any decent equipment. The sport needs to be pretty much totally destroyed in order to have a snowball's chance in hell of a rebirth in which things are done right.

http://ozreport.com/forum/viewtopic.php?t=27609
Do we really need tandem hang gliding?
Mark Frutiger - 2015/12/12 04:14:39 UTC

Who wants to see Quest, Wallaby, Lookout, the Florida Ridge and Highland go away?
I do. And twenty percent of those (at LEAST - figuring in the volume) just went extinct.

Aerotowing since the early Eighties and the equipment sucks and sucks worse than it did three decades ago. That doesn't happen by accident. That happens by DESIGN.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=34229
AT release
Davis Straub - 2016/04/01 22:07:43 UTC

April Fools, for sure.
Fer sure...

http://ozreport.com/forum/viewtopic.php?t=24534
It's a wrap
Davis Straub - 2011/07/30 19:51:54 UTC

I'm very happy with the way Quest Air (Bobby Bailey designed) does it now.
I'm ALSO very happy with the way Quest Air (Bobby Bailey designed) does it now.

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

Just as long as you're the dope on the rope waiting for the Bobby Bailey designed weak link to break before you can get into too much trouble.

http://ozreport.com/forum/viewtopic.php?t=672
Terry Spencer
Marc Fink - 2005/05/19 13:10:28 UTC

right on

Kev's response is right on and politely worded--but I don't think I can be as restrained in my response in light of Davis's eagerness to push this issue to its fullest limit.

Davis has a well-established history of posting reports which cast doubts on other pilots capabilities and judgements. Much of this I believe is due to a driving inner need to bask in his own "legend in his own mind" limelight. Davis also feels a compelling need to patronize whichever flight park he happens to be living with at the time, and thus tends to play groupie to whomever allows him to pitch his tent/traveling circus. Readers may recall Davis's glowing comments of Malcom and Wallaby while he sojourned there--but Davis has a less than glowing opinion of them now.

Another habit of Davis is to take bits and pieces of hearsay from other pilots and present them as if they add up to anything more than a hill of beans. Most irritating of all, he then argues from a position of "so-and-so said this" as the factual basis of his arguements. In other words, Davis rarely has the guts to simple say this is "what I think, based on what I have researched."

The power of media, especially the internet, lies in that bits and pieces of information can be put together in order to create spin that serves the slanted opinions of the editor. Davis is a master at this, and all the while meekly claims that he is simply serving the truth.
Christopher LeFay - 2016/04/01 22:12:59 UTC

I'm fairly certain he holds the title the other 364 days of the year, too.
The other 365 days of the year, too, this year - asshole.
Why dontchya log on over here so's we can discuss some of these issues, Christopher?
Boy am I glad I banned that motherfucker three and a half weeks ago instead of giving him any more benefit of any hint of doubt.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://ozreport.com/forum/viewtopic.php?t=47096
Aerotow primary releases?
Tom Lyon - 2016/04/01 20:15:37 UTC

I have a Falcon 4 -195 with the spinnaker release/bicycle handle set up and the extra hole drilled in the release as shown in the post by Hefalump with the big photo. I use a polypro bridle. I have a secondary barrel release on my harness. The entire set up and installation were provided to me by Tracy Tillman of Cloud 9. I am a member of the DFSC club.

I only have 20 solo aerotows...
Which means you've completed your tandem training, know how to stay in the Cone of Safety, recover from a weak link inconvenience / increase in the safety of the towing operation, handle any emergency situation Mother Nature and/or the total douchebag up front can throw at you.
...but am very happy with the system.
I see you have the same sterling AT equipment standards as...

http://ozreport.com/forum/viewtopic.php?t=24534
It's a wrap
Davis Straub - 2011/07/30 19:51:54 UTC

I'm very happy with the way Quest Air (Bobby Bailey designed) does it now.
http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Davis Straub - 2011/08/28 14:13:55 UTC

As I pointed out in a link in this thread. I was very happy to have a nice weak link when that happened to me at Marty's place near Rochester, NY.
http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Davis Straub - 2013/02/09 16:45:39 UTC

I am more than happy to have a stronger weaklink and often fly with the string used for weaklinks used at Wallaby Ranch for tandem flights (orange string - 200 lbs). We used these with Russell Brown's (tug owner and pilot) approval at Zapata after we kept breaking weaklink in light conditions in morning flights.
http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks
Davis Straub - 2013/03/06 18:29:05 UTC

I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
http://www.hanggliding.org/viewtopic.php?t=31747
Lockout
Davis Straub - 2014/09/01 15:22:41 UTC

I can tell you that I fly with a 200lb weaklink on one side of my 750lb pro tow bridle. I am happy with it.
...Davis Dead-On Straub. It's all about what one is HAPPY WITH. And what one is HAPPY WITH always seems to be a function of the way the political winds are blowing at any given moment - 180 degree shifts back and forth never seem to be significant issues.
I was nervous about aerotow release systems in general initially because I come from flying sailplanes where it's either the Tost or Schweizer release and they are very well-proven designs.
As was the standard aerotow weak link for decades. Looooong track record. Now everybody's busy proving the Tad-O-Link - a mere 54 percent more dangerous.

Get fucked, Jackie. Aviation equipment isn't PROVEN. It's ENGINEERED. The Schweizer release sucks under side loading and WILL lock up in dangerous situations. It works great when you don't really need it to - just like all the equipment and procedures in hang gliding. The Tost is bulletproof. Doesn't give a flying fuck what's going on with the planes. And it didn't need to be PROVEN because its DESIGNERS knew what the fuck they were doing and gave rat's asses.
The fact that there are different types of releases in hang gliding and different tow methods (e.g. pro-tow) was a bit disconcerting.
Doesn't u$hPa have release performance standards in its SOPs? How many of the "manufacturers" advertise that their equipment meets or exceeds them?
However, I am fully satisfied that the system I am using is reliable.
Big fuckin'...

http://www.ushpa.org/page/2016-spring-training
Spring Training
Spring Training

2016/03/22

Complacency and Denial

If I had to pick just one factor that was most common in our accidents/incidents, I would choose Complacency.

Mitch Shipley
USHPA Accident Reporting Committee Co-Chair (Hang Gliding)
http://www.ushpa.org/page/2016-spring-training
Spring Training
...surprise.
I don't know if it's as reliable as the sailplane releases I was familiar with or not, but there must be many hundreds of thousands of tows with this release system now.
And you carefully scrutinize all the incident reports published every month in the magazine to determine whether or not any of them are a bit problematic.
I asked Tracy why Cloud 9 prefers a polypro bridle and he said they have never had a single tangle of a bridle around a towline...
Meaning that he has them tangle on the tow RING left and right. NOBODY's ever figured out how to tangle a bridle on a towline before, idiot.
...and that made sense to me.
Implying that Trisa tells ya stuff all the freakin' time that DOESN'T make any sense to you.
Polypro is fairly large in diameter, and slippery.
So?

http://ozreport.com/9.098
The thin 1500 pound aerotow bridle
Davis Straub - 2005/05/03

Bob Lane said that Quest Air sold over 40 of their bridles (and Bob sold 15 or 20) during the Nationals. The Quest Air bridles use thicker Spectra and are designed not to whip around and accidentally tie themselves to the carabineer. Bob says his bridles will not do this either.

It is great to see these safer, simpler, and easy to use aerotow bridles becoming popular.
No bridle that anyone sells is capable of wrapping.
Tracy has the mounting spot on the keel figured out precisely for a Falcon, and he test flew the whole system for me.
Oh great. It's been figured out PRECISELY. How 'bout your hang point? Has that also been figured out PRECISELY. Power setting on the Dragonfly?

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3661
Flying the 914 Dragonfly
Jim Rooney - 2008/12/06 20:01:49 UTC

You will only ever need full throttle for the first fifty feet of a tandem tow. Don't ever pull a solo at full throttle... they will not be able to climb with you. You can tow them at 28 mph and you'll still leave them in the dust... they just won't be able to climb with you... weaklinks will go left and right.
Weak link? A bit under four years ago Trisa figured out that it should be PRECISELY 130 pound Greenspot with the knot properly hidden for consistent breaking strength. No everyone and his fuckin' dog are happy with one PRECISELY...

http://ozreport.com/forum/viewtopic.php?t=47192
Retracing your bridle
Image
http://ozreport.com/20.063

...54 percent more dangerous.
The balance is superb.
Nothing at all to do with how the tug is adjusting his power, airspeed, climb rate to keep you level. If he were towing a heavy tandem he'd be doing everything exactly the same.
Just the right amount of bar pressure, but very relaxed. I can focus on maintaining my position behind the tug, which is still somewhat-challenging for me if the air is really active.
Don't worry about it. Keep up the good work and you'll master it in no time.
I have the handle placement such that if I "chop" my hand over to it in an emergency without looking, I will be "guided" a bit by the basetube/upright junction and I'm certain that I'll actuate the release even if I am under duress.
Sure ya will. No fuckin' way you'll ever be in a situation in which you'll ever need every ounce of muscle you own applied continuously to keep from slamming in like in free flight launch and landing situations.
However, I actually release by looking at the handle and reaching over with my hand to depress the lever. I'm just saying that I feel confident that I could get the lever pushed in an emergency.
You've got way more confidence than I do, motherfucker...
Bill Bryden - 2000/02

Dennis Pagen informed me several years ago about an aerotow lockout that he experienced. One moment he was correcting a bit of alignment with the tug and the next moment he was nearly upside down. He was stunned at the rapidity. I have heard similar stories from two other aerotow pilots.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3391
More on Zapata and weak link
Paul Tjaden - 2008/07/22 04:32:22 UTC

I have never had a lockout situation happen so quickly and dramatically and had no chance to release as I have always thought I could do.
I've been in a lockout like those - at altitude - rigged with the best two point release on the planet. Finished up thirty feet lower than I started out. Good freakin' luck getting hit by something like that under fifteen.
Obviously, my own experience is extremely limited with just 20 tows.
- And I'd had a lot more than twenty tows under my belt.
- Obviously, you have no need of researching real world crash reports and or thinking through worst case scenarios.
But I feel that I researched this a carefully as I could...
Just a carefully as you've written this sentence. Yes Jackie, I have no doubt whatsoever that you're operating at max capacity.
...and that the experience of thousands of pilots before me using this system successfully makes me feel confident that I have a good release.
- The very same one that Trisa sold you! What a coincidence!

- And always look at the experience of the thousands of pilots before you using this system successfully and studiously ignore the scores who've used it stunningly UNsuccessfully.
I would not try to pro-tow my Falcon. Everyone I've talked to has told me that the bar pressure is very high and I think that would be dangerous (for me).
How 'bout a tandem aerotow instructor on a Moyes Xtralite?

06-03114
http://farm4.staticflickr.com/3728/9655895292_f4f808fb0e_o.png
Image

Would he be OK? Even your dickheaded tow operators have written in the magazine...
Dr. Trisa Tilletti - 2011/11

However, there is no upper tow point when pro-towing, so there is nothing but your body weight to hold down the nose of your glider while launching and towing. In that case, you should hold your weight farther forward than at best glide speed when lying prone in the cart just prior to launch, because your body needs to be farther forward while towing. In fact, vertical lockouts are all too common with pro-towing, because sometimes pilots cannot move far enough forward to keep the nose down. A vertical lockout is very dangerous for both the tug pilot and the hang glider pilot.
...that it's dangerous. Why do you need to "THINK" anything one way or another?
I also will not move up to towing with a Sport 2 or other glider until I probably have 100 hours or more on my Falcon.
What an asshole.
I'm a very conservative pilot.
So you keep telling us. I'd slash my fuckin' wrists if I were a "very conservative" "pilot" like you. REAL pilots are always pushing and advancing their limits, thinking about tight situations, training themselves to deal with them, having FUN.
I hope this is helpful to you.
Probably someone very much like you.
Matt Pruett - 2016/04/01 23:35:47 UTC

Cloud 9 is on my list of places to visit this summer, looking forward to it.
Trisa's really great people - and I have little doubt that you'll fit right in.
The fact that there are different types of releases in hang gliding and different tow methods (e.g. pro-tow) was a bit disconcerting.
That's pretty much what motivated me to start researching this, as well as some personal experiences and observations.
Like:
Matt Pruett - 2016/03/23 06:27:30 UTC

I spent quite a bit of time reading Tad Erickson's posts (probably spent a full day at it honestly), prior to making this thread. The only thing I have to say about all of that is this: ideas are cheap, talk is cheap. If someone thinks they can improve on the status quo, make a product with good documentation and sell it, get it into peoples hands, if it's a notable improvement then it will be adopted and/or influence other designs.

I don't have the expertise to build a towing system, nor do I have the flight experience to be a test pilot. Which is why I only listed products, made for the purpose, that actually exist in this thread.
I asked Tracy why Cloud 9 prefers a polypro bridle and he said they have never had a single tangle of a bridle around a towline, and that made sense to me. Polypro is fairly large in diameter, and slippery.
Hmm that's an interesting thought, what thickness do they use? Have a link to the material? What carabiner do they use at the end of the tow rope? Thanks.
Ever wonder why:
- Trisa uses:
-- a 250 foot Spectra towline but thinks it's a really cool idea to use polypro for the bridle - which is just a short extension of the towline?
-- Spectra for the FRONT END bridle?
- not one single other AT operation uses elastic bridles?
I wound up buying a linknife and the mouth release.
Great! An award winning hook knife in a tube that can be neutralized by a bit of wheat stubble and can't be used in an emergency and a one point release that can.
I'll probably put the linknife at the apex of the vbridle, it seems like a solid solution.
Yeah...

http://groups.yahoo.com/group/skysailingtowing/message/6726
Weaklinks
Peter Birren - 2008/10/27 23:41:49 UTC

You trying to tell me the pilot had time to release? Not a prayer.

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.

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.
If only it actually WERE.
Haven't decided if I'm going to use the mouth release or not, but I love the concept.
Well, the really important thing is that T** at K*** S****** had no part in its development.
Matt Pruett - 2016/04/02 05:21:22 UTC
I have the handle placement such that if I "chop" my hand over to it...
That may be true for you, and it seems like a good idea to place the handle as you mention.
Within easy reach. Just like in the SOPs.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3648
Oh no! more on weak links
Carlos Weill - 2008/11/30 19:24:09 UTC

On June of 2008 during a fast tow, I noticed I was getting out of alignment, but I was able to come back to it. The second time it happen I saw the tug line 45 deg off to the left and was not able to align the glider again I tried to release but my body was off centered and could not reach the release. I kept trying and was close to 90 deg. All these happen very quickly, as anyone that has experienced a lock out would tell you. I heard a snap, and then just like the sound of a WWII plane just shut down hurdling to the ground, only the ball of fire was missing. The tug weak link broke off at 1000ft, in less than a second the glider was at 500ft. At that point I realized I had the rope, so I drop it in the parking lot.
Where better?
A point to consider is that in an actual emergency, you may find that you hesitate to open or move your hand because most new pilot's (this was certainly the case for me) will take longer than they should to become fully aware of the problem and also over-emphasize attempting to correct the situation by force rather than release.
Yeah. That's what's going on HERE:

Aerotow launch faliure
http://www.youtube.com/watch?v=bj-qBsETXPg
Oliver Chitty - 2014/03/02
dead
24 fps

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Ollie's hesitating to open or move his hand because most new pilots (this was certainly the case for you) will take longer than they should to become fully aware of the problem and are also over-emphasizing attempting to correct the situation by force rather than releasing. Hesitates 2.6 seconds from the beginning of the clip because thinks he can fix a bad thing and doesn't wanna start over.

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0.4 seconds from the beginning of the easy reach to be safely off tow, by the way.

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Makes no attempt whatsoever to either fly out of the situation or use his glider as a crush zone.

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And he ends up having to start over anyway. What a moron.
Everyone that watches a lockout video knows what the pilot should be doing and when, but actually being in the situation and responding quickly is not the same thing.
That's undoubtedly why Davis Dead-On Straub...

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...fails to go for either of his easily reachable releases while the cart wheels are severely castering and he's about to get dragged off the cart.
In an extreme lockout that stationary leaver may feel very far away.
In ANY emergency that stationary leaver might as well have left for the fuckin' moon. How many crashes do we need to see and hear about before that point sinks in?
I would recommend...
Oh good. US hang gliding's next Jim Keen-Intellect Rooney.
...any pilot to load up their release with lots of weight, and pull the release a number of times from the flying position if possible, it's not usually going to be hard to pull, but with many of these releases it will be different than what you are accustomed to, feeling that difference a number of times I think is probably valuable.
- Which is another way of saying that none of the individual manufacturers have done this.

- Funny nobody ever makes recommendations like this for bicycle handbrakes - or Tost or Schweizer sailplane releases.

- Maybe he should also go up and practice hitting the lever in free flight when he's getting blasted on his ear by a thermal to see how the glider responds. My guess is that it'll tend to level out and resume heading - but it would be good to know for sure.

Gawd it's nice hearing you and Christopher talking and affirming my decisions to ban your douchebag asses.
Tom Lyon - 2016/04/02 11:44:19 UTC

Thanks for the advice on pulling the release when it is under a heavy load. I will consider that.
Or you could just save yourself the trouble and read what the alleged coauthor of the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden had to say about the Quallaby release a dozen years ago yesterday...

http://groups.yahoo.com/group/skysailingtowing/message/4049
Towing errata
Bill Bryden - 2004/04/01 16:20:18 UTC

Some aerotow releases, including a few models from prominent schools, have had problems releasing under high tensions. You must VERIFY through tests that a release will work for the tensions that could possibly be encountered. You better figure at least three hundred pounds to be modestly confident.

Maybe eight to ten years ago I got several comments from people saying a popular aerotow release (with a bicycle type brake lever) would fail to release at higher tensions. I called and talked to the producer sharing the people's experiences and concerns. I inquired to what tension their releases were tested but he refused to say, just aggressively stated they never had any problems with their releases, they were fine, goodbye, click. Another person tested one and found it started getting really hard to actuate in the range of only eighty to a hundred pounds as I vaguely recall. I noticed they did modify their design but I don't know if they ever really did any engineering tests on it. You should test the release yourself or have someone you trust do it. There is only one aerotow release manufacturer whose product I'd have reasonable confidence in without verifying it myself, the Wallaby release is not it.
And the "design" "modification" Bill is talking about was this:

http://www.flickr.com/photos/aerotowrelease/8305428629/
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to:

http://c2.staticflickr.com/2/1523/25679752020_89cc46e0e3_o.jpg
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And this ABSOLUTE MORON...
Towing Aloft - 1998/01

Bill Bryden became enamored with the sport of hang gliding in 1976 while residing in Hawaii and managing a bicycle shop. However he shortly thereafter moved to Illinois to pursue higher education and believed his hang gliding dream impossible in the flat lands. Bill completed an engineering degree and master's degree in business at the University of Illinois then moved to Indiana.
http://groups.yahoo.com/group/skysailingtowing/message/6120
Bridles and Releases
Tad Eareckson - 2007/01/04 05:35:32 UTC

If my designs are better (and they are - I've done my homework) say so and adapt them.
Bill Bryden - 2007/01/05 16:52:14 UTC

How did your design fair in a Failure Mode and Effects Analysis (FMEA) and in Failure Mode and Effects Testing (FMET)? What were the results of performance tests like those in the Appendix III of Towing Aloft?

What were the sample sizes of repeated tests and number of product samples (ie were they statistically significant)?

Just a little aside observation: I have supervised many projects and engineers over the years. Oddly, there often is a correlation between the robustness of a design and the engineer's humbleness regarding it. Others also have a sense of that relationship and it affects our thinking, makes us wary.

Have fun.
Bill
Tad Eareckson - 2007/01/06 00:36:14 UTC

Hi, Bill, thanks for half of the book.
Regarding the FMEA/FMET - I don't have a clue what those are. When this headache starts going away maybe I'll google those terms and give it a boost.
The sample sizes for the tests I've done were, in all cases, One (1).
Yeah, I've transcribed Appendix III to my disk, taken some ideas, and substituted others.
Does the stuff you're flying with have all those stamps of approval? Does anybody's anywhere?
(No reply. Big surprise.)

...can't figure out what the performance effect of the modification was. Maybe enhanced it, maybe degraded it, maybe had no bearing whatsoever. Who can really tell for sure without Failure Mode and Effects Analysis (FMEA) and Failure Mode and Effects Testing (FMET)?
Fortunately, my 100+ sailplane aerotows help me to the extent that I am acutely aware when I'm out of position.
How many spot landing attempts did you hafta do before you became acutely aware of the distances by which you were missing the old Frisbee in the middle of the LZ? How fucking stupid do you need to be to not be acutely aware of being out of position on an aerotow - what with the really excellent feedback a roll unstable system is constantly sending you?
I also have noticed from lockout videos that there is often a period of time when the problem is worsening, but the pilot appears to be unaware.
Yeah, the pilot APPEARS to be unaware. Probably has something more important on his mind and isn't really paying attention to what he's doing.

Bullshit Jackie. There are only two reasons people get out of position and lock out on tow:
- don't know how to fly a glider as a consequence of shit instruction and forced upright "training"
- get hit by something that overpowers their available control authority

NOBODY is EVER unaware of what's going on during an aerotow and if Davis hadn't all but totally eradicated all vestiges of intelligent life from his dump you'd currently be getting a new asshole ripped.
Davis Straub - 2016/04/02 13:00:03 UTC

Mouth release.
Rubber duck.
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=34229
AT release
Brad Barkley - 2016/04/01 22:57:44 UTC

I hear Rube Goldberg uses this set-up and loves it. Image
ImageImageImage Rube Goldberg! ImageImageImage No matter how many times I hear it that one always cracks me up! ImageImageImage
Karl Allmendinger - 2016/04/02 03:47:53 UTC

Tad Eareckson or Heath Robinson?
That one too! That's even funnier 'cause it's BRITISH! ImageImageImage

You Mission Soaring Center motherfuckers don't EVER...

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...get to make cracks about ANYBODY's tow equipment - even really crappy junk.

Rube Goldberg? What's it take to get Mission "student" Lin Lyons off tow and safely back on the ground reasonably close to the airport and ready for the next ride? Birrenator, three-string, emergency signal, tension dump, frantic search for somebody with a Swiss army knife, parachute, long search for the deployment bag, repack, repair shop for the Falcon 4. Come down on the powerlines and it gets a little more Rube Goldberg.

And let's not forget THIS:

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Mission tow student from five days shy of five months later.

http://www.hang-gliding.com/
Mission Soaring Center
2013/06/15

The Mission Soaring Hang Gliding school provides professional training on state-of-the-art equipment at our dedicated training site at Tres Pinos (near Hollister, CA)... just south of the San Jose / San Francisco Bay Area.
Don't see nuthin' 'bout no state-of-the-art equipment if you log on today...
Steve Davy - 2013/09/06 01:07:07 UTC

I talked with Pat about Lin's little adventure and what's been done to avoid a repeat.

When asked if a guillotine had been installed he expressed that he didn't like/trust the added complexity. And that his fix was to go with a two string that can't be configured incorrectly.

He has gone to a two string and added that it now has a stainless pin (rather than a plastic coated cable) engaging a spectra line loop. Said he tested it at 370lbs and estimated the pull to actuate at 15lbs.

About the auto release basically he just doesn't trust folks he's towing to release in a lockout or if the winch "runs out of gas" and the towline gets pulled back due to the retrieval line. He also told me that Rob McKenzie gave him the idea of using an auto release.

PS Pat uses a Koch two stage himself.
http://www.hanggliding.org/viewtopic.php?t=30306
Non-fatal crash in Tres Pinos, CA
Scott Howard - 2014/11/06 16:06:31 UTC

...the best i can do for now is a clip of the day b4 when i told the instructor about release problem. (still released by normal method but had to yank 3 times on release to get it to release.)
I'd like to think that Kite Strings had a bit to do with that revision.

http://www.hang-gliding.com/about/staff
Mission Soaring Center - Staff
Karl Almendinger

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Literally a rocket scientist who worked for NASA on such projects as the Hubble Telescope. Karl brings to Mission a concise understanding of aerodynamics. His background as a powered pilot and extended history of foot launch flight and past Vice President and Safety Director for the Wings of Rogallo and Hang glider test pilot provides Mission the type of depth that most schools only dream of.
Can't even spell the rocket scientist's name right.
Karl Allmendinger - 35092 - H4 - 1985/07/20 - Dan Murphy - FL AWCL TUR - ADV INST, MNTR
And the rocket scientist obviously doesn't give enough of a flying fuck to get it fixed. And not all that impressed by the collection of merit badges for an Advanced Instructor teaching in surface towing either.
Nice form, Karl. (See, Steve? You really CAN control the glider with your hands on the control tubes at shoulder or ear height.)
Good stuff to know. I'm sure Ben finds it really useful when he's having a bit of difficulty finding his way back to the airport after he's off tow.

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At the dawn of Kite Strings I'd have looked at this motherfucker's credentials, lit up, and starting prioritizing efforts to get him over here and on board with helping us get Rooney Links and bent pin barrel releases out of circulation. Now whenever I see credentials like that on a hang glider person I start hating the son of a bitch thirty times as much as I hate the garden variety moron in this sport 'cause I know that he's got the brains to do something to help get this abortion of a flavor of aviation out of the sewer it's floating down but chooses to do NOTHING at best and is way more than likely adding shit to the flow to help speed it on its way.
Steve Davy
Posts: 1338
Joined: 2011/07/18 10:37:38 UTC

Re: Releases

Post by Steve Davy »

Image

Today I asked a national champion in sailing friend of mine if anyone in sailing would do something like that. His reply was "Oh fuck no!"
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Tad Eareckson
Posts: 9161
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Re: Releases

Post by Tad Eareckson »

Hang Gliding - 1993/02

Performance Specifications for Tow Line Releases
Bill Bryden

There are many variations on the towing theme, but common to virtually all of them is the use of a release mechanism to separate the tow line from the glider and/or pilot. Review Donnell Hewett's Skying newsletters from 10 years ago and you can follow attempts to devise good releases and tow bridle systems. Talk to old-time tow pilots and listen to the stories of release problems and tales of close calls. Learn of the accidents and injuries related to release failures and one can't help but wonder.

One wonders why tow line releases have been reinvented so many times. Why have so many people been "test pilots" for new designs? Why was so much of this equipment evaluated for the first time with test flights? What can be done to prevent future injuries or fatalities? When a pilot recently suffered a fatal accident as a direct result of a release failure, it was clear that these questions and problems needed to be addressed now. But the question is how?

These questions are similar to those that were asked 15 and 20 years ago about glider design. What evolved from those questions was the Hang Glider Manufacturers Association's performance standards and testing methods to asses a glider's structural integrity, pitch stability and other qualities. Likewise, performance standards for tow line releases may provide some similar benefit. At the very least, it is hoped that a Failure Mode and Effects Analysis (see next month's issue) and some structural testing will provide better evaluation of a new design before someone attempts to fly with it.

Since it is likely that many pilots will continue to design their own tow line releases, these specifications have been kept simple enough that most home inventors can figure a way to perform these tests, yet complete enough that the results are meaningful and repeatable. They are not intended to dictate a specific design (nor should they) but simply spell out what a tow line release should be capable of doing. Also note that a design is not necessarily good just because it may meet these criteria. There are other aspects to consider like ease of use, operator error tolerance (idiot proofness), performance in unique situations and a demonstration of reliable operation over and over.

These specifications were discussed and unanimously endorsed by the USHGA Towing Committee but are not an official part of USHGA or HGMA requirements. They are still evolving and when they have matured it will be appropriate to consider if they should be adopted on a more formal basis by one of those two organizations.

SOME EXPLANATION

Section 1 spells out minimum load test for the tow line release. Some folks may consider this to be on the light side -- maybe it is. However, if tow line releases are designed to handle really excessive loads, they sometimes exhibit release problems under light loads. Besides, the weak link should break well before 600 pounds of tension is reached.

The tests in the second section are designed to assess how well the to line release functions under load. Obviously it should function under a full load with a reasonable pull on the trip cord. The limited jury polled to determine acceptable pull forces found 8-10 pounds to be normal, 20 pounds to be high and 25 the point above which they'd start considering cutting the rope. Since the purpose is to define limits beyond which safety may be compromised, the 25-pound maximum was selected for the full load situation. Similarly, for lever-type releases (bicycle brake levers or similar devices) 20 pounds was considered the maximum since some smaller pilots might not have the grip to squeeze a lever too much beyond that. Most pilots normally allow the tow force to drop off to some degree before releasing, so they will normally allow the tow force to drop off to some degree before releasing, so they likely will experience lower release forces during normal operation. The second test is designed to simulate slack tow ropes. To release, the trip cord pull force should not exceed the load created by a slack rope which can be as low as three pounds or even less.

Section three has tests designed to hopefully uncover a problem that might occur when moving around preparing to launch. The purpose of he environmental performance requirements should be self-evident. Some Region 7 pilots who tow in the winter on frozen lakes, can testify to the importance of the freezing test, especially when there is wet, slushy snow on the ground or ice. The snow soaks the release which then freezes in the breeze and dropping temperatures as the pilot climbs to altitude. The specified time to freeze he release may seem excessive, but keep in mind that there is no 25-30 mph breeze in most freezers to facilitate a rapid chilling of the release.

Hopefully these performance specifications will provide some guidance in the design and testing of tow line releases and reduce the trial in air (forgive the pun). Of course, if there are significant problems you have experienced that would not be uncovered by testing to these specifications, or problems with the specifications themselves, your input is appreciated and desired.

WARNING! These releases have DESIGN FLAWS which may result in a release failure. Such a failure may cause injury or death.

Figure A
Figure B
Figure C

PERFORMANCE SPECIFICATIONS FOR TOW LINE RELEASES

1) Load

A. Load to 600 pounds of axial pull, the tow line release should not fail, release, separate, jam, or suffer any problem.

2) Release Operation

A. With the release loaded to 300 pounds (or to the load it would experience with a 300 pound tow force), the trip cord should consistently actuate the release with a pull of not more than 25 pounds of force directly in line with the tow line or at any angle up to 30 degrees from the line of load on the release in any direction to the side, above or below the release. For lever-type releases, measure the actuation force at the point between the ring and middle fingers when the hand is gripping the lever normally. This force should not exceed 20 pounds to actuate the release. For release systems which have cables or strings that are pulled through a guide attached to the glider control frame, and pulled in a direction parallel to the control bar (like a VG string and which we'll call side-pull cables for lack of a better name), the maximum actuation force should not exceed 20 pounds.

B. After having been loaded to 300 pounds, the load should be reduced to three pounds (or the load the tow line release would experience with a three pound tow force. The trip cord should consistently release the tow line at any angle up to 30 degrees from the line of load on the release in any direction to the side, above or below the release with a pull of not more than three pounds. Lever- or cable-actuated releases should consistently release the tow line with an actuation force not exceeding 20 pounds.

3) Malfunction Prevention

A. Connect the release to the tow line and tension the combined assembly to about 10 pounds. Stretch a portion of the trip cord at 90 degrees across the tow line causing it to wrap around the tow line at about 30 degrees. Now slide the trip cord up the tow line toward the pilot continuing over and past the release. Repeat this procedure so every side or surface of the release has had the trip cord dragged across it. The trip cord should not snag or catch on any part of the tow line release in any way that might compromise the function of the trip cord (such as shown in figure B). For side-pull cable and sting-actuated releases, slide the cable over the guide mount, corner of the control frame or any other protrusions which might snag or hook the cable similar to the procedure above.

B. Connect a section of tow rope to the release. Grasp the tow line with one hand about a foot from the release bridle line(s) which connects the release to the pilot or glider. Now shake it, jiggle it and flop it around. Move your hands close together and then alternately raise on hand while the other is lowered so the release is manipulated like an upside down slinky toy. Roll the release over and repeat this process on all sides. Then, stretching out the release and tow line like normal, there should be no snarl, twist, entanglement or other anomaly that would compromise the performance of the release.

C. Inspect and manipulate the release, looking for any potential ways the release could be incorrectly assembled or connected that would compromise its function. Common problems include release pins that can be inserted too far through the last retaining string (as in figure A) or design issues such that retaining strings are under a shear load instead of tension (as in figure C).

4) Environmental Performance

A. UV Exposure - After 150 hours of direct sunlight UV exposure on the top and bottom sides of the release for a total of 300 hours of exposure, the release should still satisfy the performance requirements in parts 1-3 above.

B. Corrosion - Using water with a 5% concentration of salt, immerse the release with tow line attached in the solution and agitate for one minute. Hang to air dry at room temperature for at least one hour. Re-immerse the release and repeat the cycle 50 times, allowing the release to dry for 24 hours after the last immersion. Repeat the performance tests in parts 1-3 above.

C. Dirt Contamination - Using water with a 20% concentration by weight of very fine dirt (filter through a flour sifter), immerse the release in the solution and agitate aggressively for one minute to insure full suspension of the dirt particles and infusion of the dirt into the release. Remove and air dry at room temperature for 24 hours. Repeat the performance tests in parts 1-3 above.

D. Freezing - With e release attached to a ring or section of tow line as appropriate, soak the assembly in water and then shake vigorously to remove the excess. Place the assembly in a freezer (typical temperature 0-10 degrees F) for two hours. Quickly repeat the performance tests for parts 1-3 before any significant thawing has occurred and refreeze prior to each test.
Towing Aloft - 1998/01
Page 368

Appendix III

Release Test Procedures

Perhaps more than for any other single piece of equipment in the towing milieu arsenal, the reliability of releases is indispensable to safe towing. There have been many releases designed over the years and some are fine while others have inherent problems which lead to failures. We cannot readily point to any one type of release design which is inferior, but we can describe a test routine which, if followed, will reasonably assure that a release will work every time under all imaginable tow situations.

We do not encourage this practice, but we know it is likely that some pilot will construct their own releases. Indeed, even some production releases have not been thoroughly tested in the manner described below. Thus we strongly recommend that every tow pilot test his or her release to these simple standards.

While these standards have been endorsed by the USHGA Tow Committee, this body does not set equipment standards. Also, in some other countries the respective associations have set their own standards. We suggest that pilots contact their own associations to see if standards exist, and if not adopt similar procedures to the following.

The testing consists of three parts:

I - A series of tests under different loads and different configurations.
II - Tests to assure the release will deploy after entanglement with the towline.
III - Environmental tests.

I - LOAD TESTING

A - Load the release to 600 pounds (272 kg) straight away from its attachment (no sideways load). Upon repeated trials, the release should not fail, separate, jam, release on its own, or suffer any problem.

B - Load the release to 300 pounds (136 kg) or to the load it would experience with a 300 pound tow force:

1. For Skyting bridles, the trip cord should consistently actuate the release with a pull of not more than 25 pounds of force directly in line with the tow rope or at any angle up to 30 degrees from the line of load on the release in any direction to the side, above, or below the release.

2. For releases near the pilot, as typically occurs in aerotowing and platform launch payout winch towing, the trip cord should actuate the release in any direction to the side, above, below and even forward with no more than 25 pounds (11 kg) actuation force.

3. For lever type releases, measure the actuation force at the middle point where the hand contacts when gripping the lever normally. This force should not exceed 20 pounds (9 kg) to actuate the release.

4. For release systems which have cables or string that are pulled thorough a guide attached to the harness or glider, the maximum actuation force should not exceed 20 pounds (9 kg).

Lower actuation forces are generally desired for the above conditions, the tested limits are considered the maximum values beyond which safety is potentially being compromised.

C - After having been loaded to 300 pounds (136 kg), the load should be reduced to 3 pounds (1.4 kg) or to the load the towline release would experience with a 3 pound tow force. This test assures the release will drop a broken towline.

1. For Skyting bridles, the trip cord should consistently actuate the release with a pull of not more than 3 pounds (1.4 kg) of force directly in line with the tow rope or at any angle up to 30 degrees from the line of load on the release in any direction to the side, above, or below the release.

2. For releases near the pilot, as typically occurs in aerotowing and platform launch payout winch towing, the trip cord should actuate the release in any direction to the side, above, below and even forward with no more than 3 pounds (1.4 kg) actuation force.

3. For lever type releases, measure the actuation force at the middle point where the hand contacts when gripping the lever normally. This force should not exceed 20 pounds (9 kg) to actuate the release.

4. For release systems which have cables or string that are pulled thorough a guide attached to the harness or glider, the maximum actuation force should not exceed 20 pounds (9 kg).

D. Releases not tethered to the pilot or glider, but rather those mounted to the pilot's harness or glider in such a way as to preclude free motion of the release to align itself with the towline, may experience release difficulties when the towline exits the release difficulties when the towline exits the release at a large angle. The two stage chest releases typically fall into this category. Those releases require repetition of the above with the towline oriented:

1. 70 degrees to either side of the release as mounted on the harness or glider.

2. 80 degrees above or below the release as mounted on the harness or glider.

3. 70 degrees to either side and above and below the release.

II - MALFUNCTION CHECKS

These checks assure that the release will work of the release runs across the towline or the trip line runs across the release during tow staging.

A - Connect the release to the towline and tension the combined assembly to about 10 lbs (4.5 kg).

1 - For trig cord actuated releases, drape a portion of the trip cord over the towline on front of the release. Now pull the trip cord up the towline and over the release towards the pilot position. The trip line should not catch on any part of the towline or release in such a way to compromise the trip line's function and an easy pull should result in release. Repeat this procedure in such a way that every side or surface of the release of the release has had the trip line dragged across it.

2 - For releases actuated by a pull cable or string running through a guide mounted to the glider or harness, slide the cable or string over the guide mount, corner of the glider control frame, riser carabiners, or any other protrusions which might snag, or hook the cable similar to the procedure above. The trip line should consistently not snag or catch on any part of the tow rope or release in a way that might compromise the function of the trip line.

B - Connect a section of towline to the release. Grasp the towline with one hand about a foot (30 cm) from the release and grasp the bridle about a foot (30 cm) from the release with the other hand. Now shake the release and flop it around. Move your hands close together then alternately raise one hand while the other is lowered so the release is manipulated like an upside down slinky toy. Roll the release over and repeat this process on all sides. Then stretch out the release and towline to the normal position. There should be no snarl, twist, entanglement or other anomaly that would compromise the performance of the release.

C - Inspect and manipulate the release and look for any potential ways the release could be mis-assembled or connected in a way that would compromise its function. Common problems include release pins that can be inserted too far through the last retaining string and catch or an arrangement whereby the retaining strings are under shear instead of tension (see Figure III-1).

III - ENVIRONMENTAL PERFORMANCE

A - Moisture: Completely immerse the release with a section of towline attached in water. With the assembly soaking wet, and re-wetted during the tests as required, the release should still satisfy the performance requirements in parts I through III.

B - UV Exposure: After 150 hours of direct sunlight UV exposure on the top and bottom sides of the release for a total of 300 hours of exposure, the release should still satisfy the performance requirements in parts I through III.

C - Corrosion: Using water with a 5% concentration by weight of salt, immerse the release with tow rope attached in the solution for 1 minute then hang to air dry at room temperature for 1 hour. Re-immerse the release and repeat the cycle 24 times allowing the release to dry for 24 hours after the last immersion. Repeat the performance tests in parts I through III.

D - Dirt Contamination: Using water with a 20% concentration by weight of very fine dirt (using a flour sifter), immerse the release in the solution and agitate aggressively for 1 minute to insure full suspension of the dirt particles and infusion of the dirt into the release. Remove and air dry at room temperature for 24 hours. Repeat the performance tests in parts I through III.

E - Freezing: With the release attached to a ring or section of tow rope, soak the assembly in water and then moderately shake to remove and excess. Place the assembly in a freezer (typical temperature 0 to 10 degrees F or -18 degrees to -12 C) for 6 hours. Quickly, to avoid thawing, repeat the performance tests for parts I through III (re-freeze prior to each test).

Figure III-1: Faulty Loop Release Design

Side views

Release pin pulled
<- Tow force - Loop in shear may not release--it is too short!
<- Tow force - To prevent this dangerous problem, make last loop a bit longer.
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