Video

[groundeffect]

Nice, thanks for sharing.

[deltaman]

http://www.youtube.com/watch?v=xvc31Qqy0Ww

[Steve Davy]

"Three ring parachute release demonstration high speed"

http://www.youtube.com/watch?v=AItz8GcYx60

[Steve Davy]

"Hang Gliding Footlaunched Aerotow in Devon"

http://www.youtube.com/watch?v=3GFqoPuOsmU

[deltaman]

http://www.youtube.com/watch?v=FvoBJ9K_ruI

[Steve Davy]

"Hangglider lockout on static tow line - Part1"
http://www.youtube.com/watch?v=LvBgUdkRDhY

"Hangglider lockout on static tow line - Part2"
http://www.youtube.com/watch?v=ciAWzIW7oOs

[MikeLake]

Steve,

What do you mean by static line?
Is it what we call fixed line, a line attached to a vehicle with no winch system?
Was there an observer at the vehicle end?

Cheers

[Tad Eareckson]

In the US the convention is:
- static refers to a fixed length towline - direct connection, no winch (aero)
- stationary refers to a winch that stays in one place - no truck, trailer, or boat
despite the fact that the words are synonyms.

But that's not Steve's term. He's just quoting Mikkel Krogh's titles. And Mikkel is Danish. And I think it's a pretty safe bet that Mikkel's referring to / using a powered stationary/static winch.

P.S. ...hopefully / almost certainly with someone on it who has his shit together a lot better than the folk at Mission Soaring Center do.

[Steve Davy]

Yes, those are the titles written by the producer of the videos, copied and pasted from youtube by me.

I like the term "fixed line" rather than "static line" and I'll use that in the future.

Now can anybody tell me what kind of release Mikkel is using?

[Tad Eareckson]

Yeah, "fixed line" is a lot better convention than "static". Not surprising when this culture's conventions are also:
- "three point" for two point
- "pro tow" for one point
- "pressure" for tension
- "excellent book" for Towing Aloft
- "trail and error" for pulling a piece of fishing line out of one's ass and forcing everyone to use it for decades

The release... Not entirely - but the best I can do and some observations...

configuration:
- dolly launch
- one point bridle (the pilot and passenger are, for the purpose of the exercise, one mass)
- under the basetube routing

releases:
- passenger: Koch one stage or two stage being used as a one stage
- pilot: Koch one stage type spreader with a loop, which requires a grab and pull to starboard, instead of a lever

weak link
- primary: engaged by pilot's primary release
- secondary: may or may not be present and engaged by passenger's secondary release

There needs to be a weak link in addition to the one we can confirm - either an equal one on the passenger's end of the bridle or a double one between the towline and tow ring.

The duration of the tow - which I'm defining as the time between the beginning of forward motion and free flight with both hands on the basetube - is eleven seconds.

Two seconds worth of one handed flying are necessitated to blow the release. That's probably twice what a level slap would've required and represents eighteen percent of the tow.

Although the lockout is pretty civilized with a slow smooth progression and nothing close to a stall following separation there's a MAJOR increase in roll over the two seconds between the beginning of the action to abort and the beginning of the free flight recovery.

How 'bout we make the tow a fixed (static) line, rewind the tape, swap in idiot fucking Ryan Rooney's instant hands free release...

http://www.hanggliding.org/viewtopic.php?t=14230
pro tow set-up

Jim Rooney - 2009/11/03 06:16:56 UTC

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

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

...actuation and see what happens?

Or we can make it a payout winch tow...

http://www.hanggliding.org/viewtopic.php?t=18868
Almost lockout

Ryan Voight - 2010/09/07 02:50:00 UTC

Weak link in truck towing WILL (read: should) still break in a lockout situation... but as everyone has already pointed out, it takes a lot longer because the glider can continue to pull line off the winch.

There is a limit to how fast line can come off the winch though... so the forces still build up, and the weaklink still fails.

...and just wait for the lockout protector to do its job.

http://www.youtube.com/watch?v=_2oeb0nNIKs
Bob Buxton accident
Scott Buxton - 2013/02/10
dead
http://www.kitestrings.org/post5902.html#p5902
016-04308
http://farm4.staticflickr.com/3799/13746342624_c9b015f814_o.png


http://farm3.staticflickr.com/2809/13746340634_a74b33d285_o.png
022-04610