Towing Aloft

General discussion about the sport of hang gliding
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Tad Eareckson
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Joined: 2010/11/25 03:48:55 UTC

Re: Towing Aloft

Post by Tad Eareckson »

Towing Aloft - 1998/01

A two-point bridle weak link is most often made out of single strand 130 lbs (59 kg) test Dacron fishing line. (Note: Fishing line comes in various weights. You must make weak links and test them each time you use a new spool of material, even if its breaking strength is labeled. This line is known by the trade name Greenspot Dacron Trolling Line and is commonly referred to as "greenline".) With the tow force being divided on the bridle line, the tow force on the towline that will cause the weak link to break is theoretically twice 130 lbs or 260 lbs (118 kg). However, knots in the weak link cause it to break at a lower force than this theoretical maximum. The side bar provides additional weak link theory.
Commonly referred to as "greenline". Yeah, we hear that all the fuckin' time. I found TWO references:

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links
Marc Fink - 2007/05/19 12:58:31 UTC

Tad--you have in fact made many erroneous statements concerning accidents--mostly to back up your convictions of the faulty nature of towing. The simple fact is that hundreds of thousands of tows using weaklinks in their present configuration successfully bely your contentions that we're all crazy for towing that way.

Simply put, your statements are irresponsible and are based on your personal interpretations.

I am a tow operator--as well as a "towee." I also do aerotow tandems. Using greenline or similar line, which generally tests at 125 lbs +- 50 lbs is widely accepted because it simply works well and relatively predicatably for the enormous range of conditions and applications in towing. If this weren't true, then accident rates would be much higher and these kinds of weaklinks would have been abandoned along time ago.

A 400lb load limit for a solo tow is absurd. You claim in-depth knoweldge of what you're doing--but do you know what kind of stitching your using, what kind of tack, and how it affects the integrity of the join you're doing?

Last year's jihad was against releases--now you're going after weaklinks.

Everyone supports you making efforts to improve things--but in the process you trash the present methods as somehow being an accident waiting to happen. You might not actually say it--but the implication is that both the operators and towed pilots are being irresponsible for using faulty equipment and practices.

Do pilots need to constantly review their tow systems? yes. Do weaklinks--being the weakest link in the system, after all--need to be carefully inspected and frequently changed? yes. Do we need to constantly try to improve things? yes. Do we need to scare the daylights out of pilots with doomsday scenarios and suggest punative action for using widely accepted practices before something better comes along? Definitely not.

My apologies to the list for waking this sleeping giant.

Blue Sky Scooter Towing Method
More Details on Equipment:
V-Bridle/Release System

But with the towline we use a standard weak link like we would for aerotow... Uh... This... In this particular case it's 130 greenline, 130 pound test.
So obviously whenever you have some Industry douchebag - who can't be bothered to get even the simplest most fundamental issues right - commonly calling something something you've gotta legitimize it with another sentence of wasted bandwidth. And GreenLINE is so much easier to pronounce than GreenSPOT - saves ya a whole extra consonant sound. And after hundreds of thousands of ultra safe Greenline protected flights things like that really start adding up.

And when your Second Edition comes out do be sure to include Green-

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?
Jim Rooney - 2011/08/26 06:04:23 UTC

Troll

Hahahaha.
That seriously made me chuckle.

I get what you're saying Christopher.
Please understand that I'm not advocating professional infalliblity. Not really sure where I mentioned that, but I can understand where you might have drawn that assumption. None the less, I simply refer to "us" as the "professional pilots" as a term to describe the pilots that do this for a living. Yes, we're just humans... bla bla bla... my point is that we do this a whole sh*tload more than the "average pilot"... and not just a little more... a LOT.

We discuss this stuff a lot more as well. We vet more ideas. This isn't just "neat stuff" to us... it's very real and we deal with it every day.

It's not "us" that has the track record... it's our process.
We're people just like anyone else. And that's the point. THIS is how we do it... normal, fallible humans... and it bloody well works.

So I don't give much credence to something that someone doesn't agree with about what we do for some theoretical reason.

Take this weaklink nonsense.
What do I "advocate"?
I don't advocate shit... I *USE* 130 test lb, greenspun cortland braided fishing line.
It is industry standard.
It is what *WE* use.

If someone's got a problem with it... we've got over ONE HUNDRED THOUSAND TANDEM TOWS and COUNTLESS solo tows that argue otherwise. So they can politely get stuffed.

As my friend likes to say... "Sure, it works in reality... but does it work in theory?"
Hahahahhaa... I like that one a lot ;)
Jim Rooney - 2011/08/26 08:24:31 UTC

Thought I already answered that one... instead of quoting myself (have a look back if you don't believe me), I'll just reiterate it.

I don't advocate anything.
I use what we use at the flight parks. It's time tested and proven... and works a hell of a lot better than all the other bullshit I've seen out there.

130lb greenspot (greenspun?) cortland fishing line.
In stock at Quest, Highland, Eastern Shore, Kitty Hawk Kites, Florida Ridge, and I'm pretty sure Wallaby, Lookout and Morningside.
Not sure what Tracy up at Cloud Nine uses, but I'll put bets on the same.

Did I miss any?
Is it clear what I mean by "We"?
I didn't make the system up.
And I'm not so arrogant to think that my precious little ideas are going to magically revolutionise the industry.
There are far smarter people than me working this out.
I know, I've worked with them.
(Bobby's a fucking genius when it comes to this shit... for example.)
-SPUN as a commonly employed Flight Park Mafia approved option.

I don't think I'd totally gotten this before really looking at and thinking about this "greenline" bullshit but...

Dennis has been nothing but a u$hPa operative since maybe Day Two or Three at the absolute latest. You read these passages and they're so infuriatingly pretentious, stupid, and/or disingenuous that it makes you feel like hurling your laptop onto the floor. This trend arguably started or really started ramping up with Hewett in the early Eighties. Before we had:
Manned Kiting
The Basic Handbook of Tow Launched Hang Gliding
Daniel F. Poynter
1974

"A bad flyer won't hurt a pin man but a bad pin man can kill a flyer." - Bill Bennett
"Never take your hands off the bar." - Tom Peghiny
"The greatest dangers are a rope break or a premature release." - Richard Johnson
With Hewett we got the Center Of Mass Bridle, Infallible Weak Link, and Reliable Release.
- The greatest dangers become one's only hope for being able to survive more than two or three weekends.
- The bad pin man becomes the superb, ultra-conservative safety minded pin man
-- (whom you need to thank profusely if you survive his timely intervention).
- There's no actual advantage to keeping any hands on the bar 'cause you have:
-- an autocorrecting Center Of Mass Bridle
-- an Infallible Weak Link for the rare occasion when your Center Of Mass Bridle is overcome by:
--- contact with the control frame as a consequence of Adverse Yaw
-- a Reliable Release which allows you to release reliably
--- while flying the glider with the other hand
---- (unless you have something better to do with it)

Anything bad that happens is the responsibly of the guy on the back end of the rope. Whatever the owner of the rope did was SOP at worst and almost always heroically above and beyond the call of duty. If a Donnell Hewett hadn't codified all this crap when he did a Tim Herr would've an hour and a half later.

This is the same motherfucker - you may recall - who, just a few months prior to his development of Skyting flavor towing, bitched about u$hPa's mandate of HGMA certification for gliders in sanctioned comps. And he soon got his wish for both AT in general and AT comp launch. Tim Herr changed the SOPs to allow gliders to be towed in decertified and illegal configuration and Davis established rules to mandate same.

Dennis never had the slightest intention of writing a legitimate competent book on legitimate competent glider towing. He was the staff writer for the u$hPa / Flight Park Mafia monopoly corporation whose assignment was SOLELY to legitimize all the incompetent criminally negligent crap that the u$hPa / Flight Park Mafia monopoly corporation was perpetrating on and forcing down the throats of the glider population and general public. Bill Bryden's name was tacked on to bolster the facade of legitimacy. À la:
Dr. Trisa Tilletti - 2012/06

This article was peer-reviewed and approved for publication by the USHPA Towing Committee.
And Dennis has NEVER ONCE been exposed ANYWHERE in an online discussion where he can and will be immediately demolished before an Administrator gets half a chance to control the situation. (And u$hPa will NEVER AGAIN permit another mega asshole like Rooney to publicly and freely mouth off to his idiot egomaniacal heart's content.)

With all this in mind start reading every single sentence of all this infuriating Establishment crap and watching the lockings, deletions, bannings, expulsions and everything starts becoming...
Zack C - 2012/06/02 02:20:45 UTC

I just cannot fathom how our sport can be so screwed up.
...perfectly clear.

And count on Towing Aloft 1998/01 Version 1.0 being endorsed and sold until the end of time 'cause it's a proven system that works and it has an even longer track record than the 130 pound Greenspot Standard Aerotow Weak Link ever did or will.
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