Releases

General discussion about the sport of hang gliding
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=28452
advice please!!
Steve Seibel - 2013/02/25 17:04:53 UTC
Willamette Valley

control inputs on tow

One of the first things you'll learn is that on aerotow, it's ok if your shoulders move more than your hips/feet when you make a roll correction. Keep your arms loose and allow this to happen. In prone free flight, we learn how to not cross-control, how to make sure our body stays parallel to the keel (shoulders and hips/feet all move the same amount), or sometimes we "lead with the feet" so that the feet and hips move more than the shoulders.

On tow the physics are different and this is just wasted muscle effort. Keep your arms loose and don't fight the tendency to lead with your shoulders as you make roll inputs.

In other words, move the bar sideways but don't exert any twisting torque on it, as you would need to do if you wanted to "lead with your feet". Don't try to control yaw, either of your body or of the glider (two sides of the same coin.) Keep it loose.

Like you said below, that's a good way to put it. No "shopping cart" inputs.

They'll show you all this as you hang in a glider with someone pulling in the towline, before you ever go flying.

Steve
---
Last edited by aeroexperiments on 2013/02/25 17:53:00 UTC
Steve... SHOVE IT.

http://vimeo.com/33381400
TakeoffForCartPosition
S S - 2011/12/09 03:10
dead

99.999 percent of the time on aerotow you can wallow all over the fuckin' sky and it WON'T MATTER.

So before we get into all this fine points bullshit we need to look at the 0.001 percent of the time when control is CRITICAL.

The two times when control is critical are when the glider's:
- going up like a rocket
- locking out

(And those to situations are NOT mutually exclusive so we have ALL KINDS of potential for a really fun flight!)

In the first situation you're not gonna have any control whatsoever for at least a very long time after your Rooney Link pops 'cause you're gonna be in a severe stall. So how 'bout we talk about replacing the Rooney Links with stuff that's both legal and safe?

In the second situation you're gonna need to be doing TWO things SIMULTANEOUSLY in order to survive:
- continuously resisting the lockout with everything you've got; and
- aborting the tow.

It takes TWO hands two do the former and ONE hand to do the latter so unless you have three hands you better configure your release system such that one of your hands can do both jobs at the same time.

Think of it as if your life may be suddenly dependent upon both walking and chewing gum. If the gum's stuck to the bottom of your shoe you're gonna hafta interrupt your walking while you try to retrieve it.

So why don't you just use a plenty big enough piece of gum to satisfy the requirement and keep it in your fucking mouth for the four minute duration of the exercise?

P.S. Also note that the less input you're able to exert to resist a lockout and the longer it takes you to abort it the longer you're gonna hafta wait before further control input is gonna do anything you want (need) it to.
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=28452
advice please!!
Wayne Ripley - 2013/02/25 18:56:14 UTC

I agree that the Lookout mnt tow release would not be my first pick. I had [have] one for 5 year's or so and just went back to a bike release. It's easy to release when you don't want to by moving your hand under tow...
Really?

4:00
http://www.youtube.com/watch?v=pC1yrdDV4sI


I guess nobody bothered to tell this guy. Odd, cause he's a product of the very fine aerotow operation at which Dennis Wood works and Zack Marzec was working prior to his untimely demise in a freak aerotowing accident precipitated by a gust of wind causing the glider to release from the plane prematurely.
...and if you need to get off low[say under 50 feet] you have to get your hand out and find the down tube real fast and under a lot of pressure to do so.
But don't worry. You'll always have plenty of safety margin available...
Doug Hildreth - 1991/06
USHGA Accident Review Committee Chairman

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.
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.
Dennis Pagen - 2005/01

By the time we gained about sixty feet I could no longer hold the glider centered - I was probably at a twenty degree bank - so I quickly released before the lockout to the side progressed.

The glider instantly whipped to the side in a wingover maneuver.
http://groups.yahoo.com/group/skysailingtowing/message/6726
Weaklinks
Peter Birren - 2008/10/27 23:41:49 UTC

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.
...while you're finding it and getting it to work.
Also if you do have to get off low remember you have wheels so rather then try to get upright just come in on the wheels,it becomes a nonevent.
Assuming, of course...

http://ozreport.com/9.179
Fatality Report
Angelo Mantas - 2005/08/30

The glider continued rotating left and dove into the ground, first hitting the left wing tip, then nose. The glider's pitch was near vertical on impact, confirmed by the fact that the control bar, except for a bend in one downtube, was basically intact, whereas the keel and one leading edge snapped just behind the nose plate junction. This all happened fairly quickly. Based on witness and tug pilot accounts, the glider was never over a hundred feet.

Despite help reaching him almost instantly, attempts to revive him proved futile. Mike suffered a broken spinal cord and was probably killed instantly.
...you're coming in with the kingpost pointed up and at a nice shallow glide.
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=28452
advice please!!
Craig Hassan - 2013/02/25 19:08:38 UTC
Ohio

My first release was a Lookout looped handle release. I like it. Never had an accidental release.
Yeah Craig, those Lookout Releases are absolutely amazing...
Ralph Sickinger - 2000/08/26 22:18:20 UTC

Under sled conditions, I decided to borrow Brian Vant-Hull's glider instead of setting up my own, since we both fly the same type of glider. Brian's release is a different style, but I tested it twice during preflight to make sure I was familiar with it. After towing to altitude, Sunny waved me off; I pulled on the release (hard), but nothing happened! After the second failed attempt to release, I thought about releasing from the secondary, but before I could move my hand the tug stalled and started to fall; Sunny had no choice but to gun the engine in attempt to regain flying speed, but this resulted in a sudden and severe pull on the harness and glider; I was only able to pull on the release again, while simultaneously praying for the weak link to break. The release finally opened, and I was free of the tug.
http://ozreport.com/forum/viewtopic.php?t=17166
Accident at Whitewater
Davis Straub - 2009/09/01 19:09:48 UTC

An eye witness reports:
Approximately ten emergency vehicles were parked all over the runway.

The EMTs were carrying a (presumed) pilot out from under the wreckage of a hang glider next to the runway. They loaded the victim/stretcher into an ambulance, but didn't drive away. Stayed parked on the runway for at least a half an hour. I don't yet know what the outcome was.

Later heard that he was evacuated by helicopter because of a head injury.

Conditions: 9 am local time, 55°F, sunny and clear, with little or no wind.
...in their capacities for not releasing accidentally. It all boils down to...

http://www.hanggliding.org/viewtopic.php?t=11497
Aerotow release options?
David W. Johnson - 2009/04/11 05:46:23 UTC

I have the loop style that LMFP makes. Matt is particular about the quality of the product that goes out and you will get something reliable. I was there one time when they had a new person make a batch of them. Matt was unhappy with the quality and cut them all in half to ensure they could not be sent out. I hope that tells you about their quality.
...Matt's zero tolerance quality control system. When he says black cable housing he sure as hell doesn't mean dark gray.

But to tell you the truth, you really had me at "I like it."
I only hooked one finger into the loop, so getting it out was never an issue.
Really great that...

Image

...that was never an issue.
I used my instructors brake handle release to start with and always hit the barrel release instead of the brake handle. (I learned on a scooter and the barrel was my primary release for that.)
Cool! And I'll bet he was using one of those special Quest carabiners for a tow rig so there was no possibility of...

http://ozreport.com/forum/viewtopic.php?t=11591
Where to put the weaklink - the HGFA rules
Rohan Holtkamp - 2008/04/21

Once again history has shown us that this thread-through system can hook up and the hang glider remains being towed by the keel only, with the bridle well out of reach of even a hook knife. I know of just one pilot to survive this type of hook-up, took him some twelve months to walk again though.
...the bottom end of the bridle wrapping.
I ditched the upper rigging about the time I got my AT sign off and only tow from the shoulders now.
Yep. Much safer for the people...

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Paul Tjaden - 2013/02/07 23:47:58 UTC

When the lift/turbulence was encountered, the weak link on the tow line broke as the nose of the glider pitched up quickly to a very high angle of attack.
...who've mastered that technique.

By the way...

http://www.hanggliding.org/viewtopic.php?t=26870
weak links
Craig Hassan - 2012/08/16 11:15:57 UTC

So my suggestion is, don't break your weak link and it won't cause you any problems.
EXCELLENT advice on the weak link issue.
Apparently, the glider stalled or possibly did a short tail slide and then stalled and then nosed down and tumbled.
We really need more people getting that word around. I'm thinking there should be a question on the written test to make sure everyone's totally clear on that most critical of issues.
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=28452
advice please!!
Paul Edwards - 2013/02/25 19:53:51 UTC
Tennessee

I'm far from an expert, only towing occasionally...
Yeah Paul, you're probably about the only person on The Jack Show who isn't an expert on towing.
...but FWIW I like the Lookout style release.
Did you read...
The new GT aerotow release, new as of July 11th 2009, is designed to be used with a V bridle and a 130-pound green stripe Dacron tournament fishing line weak link. At this time it is not recommended to use this release with a higher value weak link. We are confident that with an ultimate load of 130 pounds at the release point, the new GT aerotow release works better than all cable releases that we have experience with.
...the owner's manual?

Do you understand that that's the same Rooney Link that just killed Zack Marzec and on the two point bridle you're using with the release it's under fifteen percent higher loading than it was on the one pointer Zack was using?
I wouldn't want a release that would require me to take my hands off the bar to actuate.
According to the owner's manual and as field experience has borne out it WILL fail and Plan B is to use the hook knife that comes in the package deal so, dude, you HAVE a release that requires you to take your hands off the bar to actuate.
I've never had an accidental release.
- And I'm pretty sure you're in good shape with this hardware in that department.
- So have you ever had an "accidental" Rooney Link failure?

Not that that's a safety issue because whereas accidental releases are extremely dangerous and have killed people like Brad Anderson and Eric Aasletten, Rooney Links always INCREASE the safety of the towing operation - at the negligible costs of a bit of inconvenience every now and then and being unable to get to a workable altitude on good soaring days.
I know many many pilots who aren't concerned about this (anyone who pro-tows for example)...
And they're the pros. So, OBVIOUSLY, they're the ones we should be listening to and emulating.
...so let me reiterate that this is just me voicing my humble preference.
Yeah, well, fuck you dude. I'm going with the opinions of the top notch people like Davis...

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.
...and Paul.
Paul Tjaden - 2011/07/30 15:33:54 UTC

Quest Air has been involved in perfecting aerotowing for nearly twenty years.
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.
Oh, by the way...

Image

Have you gotten in touch with your scooter tow driver for his take on what happened at his flight park at the beginning of the month? Or...

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

The tow line to release interface

Jim, as I am starting to play with Elektra Tow (ET) at Quest Air (the battery powered "scooter" tow system you and Adam got me jazzed up about up at Highland) I've watched this thread closely. We all can learn.

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.
...should we just continue giving weight to the comments of the tug driver with the keen intellect?

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec
Jim Rooney - 2013/02/12 18:00:27 UTC

Your second statement is why.
I just buried my friend and you want me to have a nice little discussion about pure speculation about his accident so that some dude that's got a pet project wants to push his theories?

Deltaman loves his mouth release.
BFD

I get tired as hell "refuting" all these mouth release and "strong link" arguments. Dig through the forums if you want that. I've been doing it for years but unfortunately the peddlers are religious in their beliefs so they find justification any way they can to "prove" their stuff. This is known as "Confirmation Bias"... seeking data to support your theory... it's back-asswards. Guess what? The shit doesn't work. If it did, we'd be using it everywhere. But it doesn't stand the test of reality.

AT isn't new. This stuff's been worked on and worked over for years and thousands upon thousands of tows. I love all these egomaniacs that jump up and decide that they're going to "fix" things, as if no one else has ever thought of this stuff?

But back to the root of my anger... speculation.
Much like confirmation bias, he's come here to shoehorn his pet little project into a discussion. Please take your snake oil and go elsewhere.

Tune him up?
Yeah, sorry... no.
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=28452
advice please!!
Bob Flynn - 2013/02/26 02:33:55 UTC
San Diego

Yup. I own and have used the Lookout release and was aerotow trained with it. It works well, doesn't hang up, and needs just a sideways motion of the hand to actuate it.
Great! So we can totally ignore all those reports and videos of people having to struggle for extended periods to pry them open!
Simple and effective.
Just like your Flytec vario and the turbocharged 914 Rotax on the Dragonfly.
The brake handle release is popular and I see it in alot of videos but I don't want something on the downtube that might poke me in the eye in a rough landing.
Yeah.

We have:

- some totally ungodly number of tows with Quallaby Releases

- failures - premature releases, cable binding, overload, hangups, brake lever spinning, bottoming out, inaccessibility - at altitude so routine that people stopped thinking they were worth mentioning

- the deaths of Rob Richardson, Mike Haas, and Robin Strid

- ZERO reports of ANYBODY EVER being poked in the eye under any circumstances - but you're worried about being poked in the eye. Fatal lockouts - which we've had - no problem. But God forbid we should take a chance of being poked in the eye.
Just my .02 worth.
Oh no. That one was totally priceless. Please - keep them coming.
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=28452
advice please!!
flying dutchman - 2013/02/26 03:02:57
Valle de Bravo
Toluca, Mexico

I recommend to connect the release to your shoulders and not to your chest...
If it's connected to the chest, heavy oscillations may occur.
If it's connected ANYWHERE heavy oscillations may occur. If you're not connected to anything at all heavy oscillations may occur.
Part of the "Skyting Criteria" is "center of mass towing" which is not conceived if it's connected to your chest.
The "Skyting Criteria" are mostly and - on several issues - EXTREMELY full of crap and "center of mass towing" is totally full of crap. The glider doesn't know or care what the tension's transmitted though before it arrives at the hang point (although the pilot really wants half or more of it going through him and his suspension).
My Tenax harness has loops at both chest and shoulders but on the shoulders were hidden in the shoulder bands.

Good luck.
Yep, that's what most aerotow flights are banking on to be able to do it again next weekend. And it works damn near all the time.
miguel
Posts: 289
Joined: 2011/05/27 16:21:08 UTC

Re: Releases

Post by miguel »

Are there construction instructions for your release? Point me to them as I was following links and ended up on Peter Birren's board.
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Releases

Post by Tad Eareckson »

Yeah:

http://www.energykitesystems.net/Lift/hgh/TadEareckson/index.html
mousetraps
Warning... They're REALLY tedious but when used in conjunction with the photographs:
http://www.flickr.com/photos/aerotowrelease/
they're not impossible to decipher - even if English ain't your first language.

Please try not to end up at Peter's again. That's really not a place at which you wanna be.
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=28759
Karen Schenck? (I think)
Mike Badley - 2013/04/01 20:52:00
Sacramento

Karen Schenck? (I think)
Schenk.
Does anybody remember the incident involving Karen (Bay Area pilot with Berkeley Club)....
Yes.
...at Hobbs, New Mexico...
No.
...around twenty years ago? Her lockout came up in discussion the other day and I needed to get the specifics (when this actually happened, what the whole situation was, etc.). My recollection was that it was at a Hobbs Tow Meet and when she launched she immediately radioed for more pressure on the brake drum, which locked her out at low altitude and spun her in at high velocity without breaking the weak link.
Gee, the focal point of a safe towing system and it didn't break when it was supposed to. Go figure.
Any details would be appreciated.
Doug Hildreth - 1991/10

1991/07/15 - Karen Schenk - 26 - Advanced - Extensive foot-launch; seven tow launches - Pacific Airwave Magic IV 155
Big Spring, Texas - head, face, pelvis, thigh - fatal

Event

Her first flight of the day was a late morning launch to 1800 feet, but she was not able to get up and go XC. Second launch was hurried because others had been able to go cross-country and she was anxious to follow. Immediately after leaving truck bed, the pilot asked for increased winch pressure (a technique usually reserved for greater than 500 feet of altitude). Then she asked for a second increase in winch pressure, and at 75 feet, she entered a "lock-out", released from tow, and dove onto runway.

Comment

The thermals that day were not strong or violent. The reporter speculates that the pilot was anxious to get up and away on an XC flight, that she launched in some sink before a thermal, that she was not climbing as she would have liked, that her calls for increased pressure were followed by entering a thermal which banked her to the right, and that she chose to release.

We have received many accident reports like this: most were injuries (usually significant) but some have been fatalities. If we are going to tow safely, we must be prepared to deal with this problem.

This is the kind of scenario is described in Jerry Forburger's article "Crooked, Tight and Low" in the October 1990 issue of Hang Gliding, page 18. This article does an excellent job of describing corrective procedures for being "locked out" on tow. If you tow, please read this article, and mentally practice your response to a lock-out.
Sorry Doug, the article's crap and Jerry's a major asshole.
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=28759
Karen Schenck? (I think)
Dave Hopkins - 2013/04/02 00:44:25 UTC

I remember the accident . I knew her. I was living in the bay area.
There was some strange sounding stuff aout that accident.
There's some strange sounding stuff aout your sentences.
I think that was one of those setups with the winch on the bumper controled from inside the cab. She had lots of pressure but was not climbing. I always wondered if she had the line above the bar.
She had the bridle over the bar and she asked for TWO tension increases?
It shouldn't have happen. Something had to be rigged wrong. That's my opinion.
Just what we need - so much more entertaining than data.
Mike Badley - 2013/04/02 05:08:22 UTC

I don't think a line over the bar would lock you out.
Any line attached anywhere routed any way you like to a glider can lock it out and kill it.
I never liked the payout winch launches because you could never tell if you were going to just drift off the mount (because the brake was too loose)...
Bullshit. You can rocket off a platform just fine without the glider even being connected to a towline.
...or rocket up with PIO's because the brake was barely paying out.
- Nobody ever got scratched as a consequence of rocketing UP.
- A PIO is a PILOT Induced Oscillation.
- Yeah, sometimes in towing you need people who know what the fuck they're doing on the front end.
- So what's stopping you from releasing?
Foot launching is so much better...
Bullshit. Foot launching - for free flight or tow - is a zillion times more dangerous than platform, dolly, or wheel launching.
...and I use a Hewitt...
Hewett.
...style bridle which has an over/under self adjusting rig.
Junk.
I also use Peter Birren's 'Link-Knife' set up which means a fresh weak link every tow.
And a fresh weak link is always a perfect weak link. You can always count on it breaking when it's supposed to and not a second before.
Dave Hopkins - 2013/04/02 13:52:12 UTC

There was a recent video of a lockout induced by the line over the bar .
Bob Buxton accident
http://www.youtube.com/watch?v=_2oeb0nNIKs
Scott Buxton - 2013/02/10
dead
http://www.kitestrings.org/post5902.html#p5902
IT WAS PLAIN THAT AS THE LINE SNAGS THE BAR IT WILL INDUCE A LOCKOUT.
The bridle didn't snag the bar.

016-04308
http://farm4.staticflickr.com/3799/13746342624_c9b015f814_o.png
Image
Image
http://farm3.staticflickr.com/2809/13746340634_a74b33d285_o.png
022-04610

It slid to the port control frame corner as the glider turned away to starboard.
looks really bad.
It WAS really bad.
If the line is over the bar we need to abort quick or the operator needs to release you quick.
And since nobody thinks it's worthwhile to engineer a release which the pilot has any chance of blowing in an emergency situation it's pretty much all up to the operator - and this is a really excellent example of how that usually goes.
I too have always foot launched I like it. Smooth transition to the air.
Except when you end up like Ed Reno, Chris Thale, or Eric Thoreson. And then we've got all those people who don't like to tension their suspension just before they run off the ramp.
Brian Scharp - 2013/04/02 14:07:51 UTC

This?

http://www.hanggliding.org/viewtopic.php?t=28305
Bob Buxton Truck Tow Accident Video
Scott Buxton (I Soar AZ) - 2013/02/10 10:17:16 UTC
Phoenix

Hello,

I am posting this for my Dad, Bob Buxton. My Dad wants to make the video of his truck towing accident on 2012/10/03 public so that others may learn from his mistake.

The cause of the accident was tow line was hook up over the control bar. Pilot error.

Bob has been Hang gliding 38 years incident free. Mostly mountain flying. He has truck towed a handful of times. He knew the tow line was supposed to go under the base bar. Just made a mistake hooking it up.

Bob wants everyone to know he takes full responsibility for the incident and there is no one to blame but himself.

What we can learn from this accident is to have a checklist, go through the checklist and make sure everything is good to go before take off and flying. Not just truck towing. Have a checklist and go through it every time you fly.

Bob is still recovering at health south Rehab Facility in Glendale. Bob suffered a severe head injury (bleeding on the brain). He still has a long road ahead of him in recovering. Bob wants to say thank you for all the thoughts and prayers.

Bob Buxton accident
http://www.youtube.com/watch?v=_2oeb0nNIKs
Scott Buxton - 2013/02/10
dead
Yes.
Post Reply