Releases

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

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=21377
AT several Questions
deltaman - 2011/04/04 07:14:09 UTC

I'm a federal instructor and don't earn any money with tandem. We work for free, just to promote our sport. That's not my real job. I won't travel in US to learn where to put wl on the V-bridle system.
1. Not saying much but proof that you're at least a little smarter than the assholes you're talking to.

2. If you were a whole lot smarter than the assholes you're talking to you'd be talking to me instead.

3. If you needed to travel to a flight park to find someone who understood something useful about weak links and bridles you'd hafta go to Australia - Dynamic Flight in particular - definitely not the US.

4. Weak link placement isn't rocket science - mostly common sense and grade school arithmetic.

5. But before you start putting weak links all over the place you hafta know what a weak link is. You're using a loop of 130 pound Greenspot and that means you don't have a clue.

6. You need to achieve some measure of competence before you start promoting anything.
I'm an old AT pilot, a tug, and a good pilot...
No. You may be a skilled flyer but you're not a pilot.

A pilot:
- understands what the fuck he's doing and why
- doesn't do or use something just 'cause a whole bunch of other assholes are doing or using something

You're using a bent pin release and dangerously understrength weak link, configured such that there's no guarantee you're gonna be able to benefit from either following a wrap, and assuming that you're gonna be able to handle an emergency while flying with one hand.
...and can understand if someone explain me clearly.
And you're also talking to a bunch of slimeball shitheads instead of someone who DOES know what he's talking about and can and would love to explain things to you clearly.
Jim,
I tried to draw what you suggest on this video. Am I right ?:

http://www.youtube.com/watch?v=UxyTHdF1h1A
WL & Tandem
dead
http://live.staticflickr.com/65535/51964126643_c3373097e6_o.png
Image
Yeah, 'cept:
- If your primary is what I think it is all three of your releases suck.
- Your secondary bridle is ten times longer than it should be.
- You haven't told us what your weak link strengths are.
- Why does this hafta be a video?
*Have you never had failure release by tandem with WLs everywhere ?
Aside from ensuring that a release isn't overloaded, what do you think a weak link has to do with release failure? Do you expect the weak link to automatically blow whenever it senses that you're in the kind of danger that necessitates your being off tow and hold when coming off will kill you?

A three hundred pound weak link does two things - holds when it's loaded below three hundred pounds and blows when it's loaded to three hundred pounds.

And bear in mind that a crap weak link combined with a crap release can be worse than no weak link at all. That's what killed Robin Strid and Shane Smith.

And what does "tandem" have to do with anything?
*About WL on the primary release:

http://ozreport.com/forum/viewtopic.php?t=11655
Wrapping bridles around loops, rings, links and carabineers
Davis Straub - 2008/04/23 16:53:28 UTC

Now Jim was not so dumb as to do this test without a backup plan (although he didn't expect the glider to pitch down so rapidly). He had the weaklink from the V-bridle line attached to a spinnaker shackle that was connected to a brake type release. He had his hand on the brake lever. When he released the barrel release, and the rag snagged the line, he didn't have time to hit the brake lever before the nose went over (and the weaklink didn't break). He then hit the brake lever and fortunately the glider recovered (it was a Falcon after all).
Yeah, but Jim was so dumb as to do this idiot pointless "test" in the first place. Kinda like standing under a coconut tree for a long time to see what'll happen instead of just watching a couple of Gilligan's Island episodes. And the better part of thirty years ago the Hewett Bridle told all the people too stupid to understand what happens when you tow a glider from the keel everything they really needed to know about what happens when you tow a glider from the keel.

It's absolutely mind boggling that anybody can get an AT rating - let alone sign one off - being too freaking clueless to know and understand what's gonna happen.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=21377
AT several Questions
Jim Rooney - 2011/04/04 10:25:23 UTC

Yeah, looks right to me.
Yeah, Delta, if that don't scare ya shitless nothing will.
Setup this way, you can get rid of the entire bridal system if you ever need to.
Yeah, sure ya can, Head Trauma...

http://www.hanggliding.org/viewtopic.php?t=11497
Aerotow release options?
Axel Banchero - 2009/06/20 04:57:01 UTC

I just kept hitting the brake lever for a few seconds in WTF mode, and the instructor used the barrel release.
Ralph Sickinger - 2000/08/26 22:18:20 UTC

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...
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3107
I have a tandem rating!!!
Lauren Tjaden - 2008/03/23 22:20:15 UTC

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

Anyhow, the tandem can indeed perform big wingovers, as I demonstrated when I finally got separated from the tug.
Steve Goldman - 1982/12

In the first incident, as I said earlier, I got into violent yaw oscillations. There was no way that I could let go of the control bar and pull the release.
Joe Gregor - 2004/09

Highly experienced mountain pilot aerotowing a newly-purchased glider experienced a lockout at low altitude. Witness reports indicate that the glider began oscillating immediately after leaving the launch dolly. The weak link broke after the glider entered a lockout attitude. Once free, the glider was reportedly too low (50-65' AGL, estimated) to recover from the unusual attitude and impacted the ground in a steep dive. The pilot suffered fatal injuries due to blunt trauma. There is no evidence that the pilot made an attempt to release from tow prior to the weak link break, the gate was found closed on the Wallaby-style tow release.
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 2008/06/02 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 degrees 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.
http://ozreport.com/9.009
2005 Worlds
Davis Straub - 2005/01/11

Rohan Holtkamp did an analysis of the accident, in particular the bridle and weaklink, which never broke. The weaklink was caught on the release mechanism, a standard spinnaker release found on bridle systems used at Lookout Mountain, Moyes, Wallaby Ranch, and Quest Air. The release clamp has an arm that is thicker at the release point and this held onto the weaklink which consisted of multiple loops of thick line.
http://www.hanggliding.org/viewtopic.php?t=21033
barrels release without any tension except weight of rope..
Bart Weghorst - 2011/02/25 19:06:26 UTC

But I've had it once where the pin had bent inside the barrel from excessive tow force. My weaklink was still intact. The tug pilot's weaklink broke so I had the rope. I had to use two hands to get the pin out of the barrel.

No stress because I was high.
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 (.8 G). 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.
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.
...just as long as long as there's not much slop in the cable, there's not a whole lot of load on the system, you're not holding much pressure, you're not oscillating, you can fly a glider with one hand or what happens after you try doesn't matter, you can reach the lever, the lever doesn't flop around to the far side of the downtube, the weak link doesn't hang up on the spinnaker shackle gate, the bent pin doesn't bend any more than it was to begin with, you can find and get a grip on the stubby little barrel, and you've got plenty of time and altitude.
The weaklinks can get rid of it as well and will likely be faster at doing so. I've rarely had to release the entire system, but I have had to. I can only recall one or two times.
Problem, Head Trauma...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3035
Tad's Barrel Release and maybe an alternative
Jim Rooney - 2008/02/13 09:06:35 UTC

When you first showed me the straight pin release, I told you I wouldn't touch it because "I had to give instructions on how to use it so that people would not rig it wrong". I showed you how you could rotate the pin sideways and close the barrel... and pointed out how this was not possible on a Bailey release. I told you if you fixed that, then I'd use it.
You tend to recall things that had no basis in reality. And remember the time you recalled having connected yourself to your tandem glider - but hadn't?
The Press - 2006/03/15

In a video, he was seen to hold on to the glider for about fifty meters before hitting power lines.
But man I was glad to have all those backup release options available at the time.
You're welcome - motherfucker.

So Delta...

http://ozreport.com/pub/fingerlakesaccident.shtml

See how this asshole has two release options "within easy reach of the pilot"? Notice the way he's not easily reaching them when the shit's hitting the fan?

Image
Image

Think about it.
Zack C
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Re: Releases

Post by Zack C »

Tad, just wanted to say that I took your stuff up for the first time Saturday...three flights, no issues.
Image

(By the way, that image is on Photobucket and has a 1280x960 resolution. I'm not sure what Photobucket's maximum image size is.)

Zack
deltaman
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Re: Releases

Post by deltaman »

Tad,
I read you too, even if it's hard as your way to speak is like a fishmonger. In french we say : "parler comme un poissonnier" or "..comme un chartier".
BTW, "bent" is "courbée" or "tordue".
I think interesting what do you write and don't ask you yet cause it seems you explain it before and don't want you to repeat it one more. So I will read you and all your doc as I read part of some and see your pics already, and then will come back with all my questions..
Please be carreful with irony as my english is not good and confusions aren't far.
If you are impatient, first questions:
with straight pin is the necessary force to pull in high load configuration, not stronger than with a bent one as the contact with the barrel is all the length ?
Where can we buy straight pin ?
Do you sell your release or do we have to make a copy ?

PS:My primary release is a GT from LMFP.
Warnarr
Posts: 32
Joined: 2011/03/31 20:10:40 UTC

Re: Releases

Post by Warnarr »

first questions:
with straight pin is the necessary force to pull in high load configuration, not stronger than with a bent one as the contact with the barrel is all the length ?
Where can we buy straight pin ?
Do you sell your release or do we have to make a copy ?
Hi Deltaman,
If the fishmonger doesn't mind let me try to answer the first question.
I've got a little French blood in me and I've never mongered a fish in my life.. :)

There is only one contact point in the barrel of both the straight pin and the curved/bent pin.
The straight pin only contacts the barrel at the tip of the pin, and not the full length of the pin.
The bent/curved pin contacts the barrel at the apex of the curve, midway along it's length.
The contact (pressure) point on a curved pin will be a little wider than on a straight pin

A curved pin is essentially like cutting a straight pin in half.
The first contact point in the barrel is at the mid point length of the pin.
The pressures against the side of the barrel are much higher because of the effective shorter length of the pin.
Tad can give the details of the pressures involved but it goes up enough to actually bend the pin in the barrel making it impossible to release.

The curved pins truly are a loaded gun waiting to go off.
I'm wanting to know how to get straight pin releases, myself.

Warren
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

Hi again Antoine, thanks much for participating.
...parler comme un poissonnier...
Yeah, I've come to realize that when you're dealing with hang glider people it's almost always a huge mistake to be polite or subtle or worry about making enemies.

You don't need to apologize for your English because it's a lot more functional than my French and I took six years of it starting in junior high school. I never really got to use it so I've forgotten almost all of it but I can probably figure out what you're saying if you need to say it in your language. And, like I said, I have a sister who's pretty fluent a phone call away.

Warren has already explained the issue of bent/curved versus straight pretty well but let me review and expand a bit.
with straight pin is the necessary force to pull in high load configuration, not stronger than with a bent one as the contact with the barrel is all the length ?
ABSOLUTELY NOT.

Warren's right that the areas of contact are about the same but contact area has absolutely NOTHING to do with resistance. If you have a long cardboard box full of books it's no easier (or harder) to drag or push it across the floor on one of its ends than on one of its sides.

The barrel release is a LEVER - a second class lever. The fulcrum (pivot point) is the eye of the pin and the load (tow tension) is being applied between the fulcrum and the far end of the lever. The closer the load is to the fulcrum and the longer the lever the more mechanical advantage you have.

As Warren says with the curved pin the contact point defines the effective length of the lever and with the curved pin the second half isn't doing anything - you're effectively cutting your lever arm in half. It's like trying to play tennis holding the handle in the middle - but much worse.

And it's still worse than what Warren describes because a curved pin needs a wide barrel and the middle of the pin forms a large angle with the inside and is thus side loading it with a lot of force.

Summary... You want the load as close as possible to the eye, a long STRAIGHT pin, and a NARROW barrel which holds the pin straight back until the instant it clears. And you also want the barrel about four inches long so you can get a good grip on it. And you also want the barrel thin on the outside to lessen the likelihood of it catching on your basetube and opening prematurely.

A tandem glider should only be towed two point (pilots and keel) - not one point (pilots only). A fully loaded Wills Wing Falcon 3 Tandem flies at 571 pounds. Although I like a weak link of 1.5 Gs, due to probable limitations of the tug and its release I'd say you can get away with a one G weak link.

Assuming you have a primary bridle long enough to form a sixty degree angle at the tow ring you need a 328 pound weak link at the top of your bridle. Below your tow ring you need a weak link 1.2 times that - 394 pounds.

A barrel release on your shoulder will be feeling half that - 197 pounds.

At 197 pounds you will need to pull 32 pounds to blow a Bailey (curved pin) release. You can blow a straight pin at just under ten.
Where can we buy straight pin ?
http://www.paragear.com
Rigging Equipment

Note... At:

http://www.energykitesystems.net/Lift/hgh/TadEareckson/index.html

there's an extensive document called "mousetraps" which contains detailed construction information and sources for materials.
Do you sell your release or do we have to make a copy ?
I can sell you some equipment but I'd hope that people learn how to make it themselves.
My primary release is a GT from LMFP.
I'm not crazy about it but you could do a lot worse. (That's what Zack's using.) You could also do a lot better and much cheaper from Joe Street in Ontario at:

racingthecloudsatgmaildotcom

But to really do this right you should build it into the glider and I'd be more than happy to help you with that.

Thanks again, stop talking to those total imbeciles on the other fora, and DEFINITELY don't waste your euros on plane fare to the US.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

Zack,
Tad, just wanted to say that I took your stuff up for the first time Saturday...
1. Rather nasty bend in your starboard nose wire. Better have that checked out by someone who knows what he's doing.

2. Short sleeved T-shirt, no gloves. Good way to hook a thermal to get to ten grand and ensure that you're gonna blow a landing on asphalt.

3. Where are the videos of the one point tow and wangs?

4. Is there any way you can Photoshop out the hook knife?
...three flights, no issues.
5. Which is another way of saying that Matt's release worked OK and my weak links held and my bridle didn't wrap.

6. Looks like you got the secondary assembly oriented right.

7. Were any of the other kids the least bit interested?

8. Seeing as how my career is over it's cool at least see my stuff go up.

9. I couldn't get ahold of anything better than the 800x600 you embedded. Can you wire me a copy of the full resolution original? That's the only shot I know about of any of my stuff in the air.

Warren,

I used to car pool to a lot of sites with Mike Chevalier - even signed his Aerotow ticket (nearly twenty years ago). He's the brother of Tracy Chevalier who's a major rock star in literary circles (Girl With A Pearl Earring).
The curved pins truly are a loaded gun waiting to go off.
They've already gone off. We're just not sure that they've hit anybody - yet.

Yeah, I can set you up with real nice barrel releases too but...

http://www.flickr.com/photos/aerotowrelease/8322228469/
Image
Image
http://www.flickr.com/photos/aerotowrelease/8323290260/

Anybody who can cut a piece of aluminum tubing and tie a knot in a piece of leechline can make something perfectly functional.
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Tad Eareckson
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Re: Releases

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=21377
AT several Questions
Davis Straub - 2011/04/04 16:14:11 UTC

I feel that there have been language issues in this thread.
Yeah, Davis, there have. But I'll betchya his English is a helluva lot better than your Nothing Else.
Bart Weghorst - 2011/04/05 00:53:14 UTC

I feel the same.
Where it comes down to my suggestion: Maybe it's because a Frenchman and a Dutchman are trying to communicate in English :-)
Nah, the problem is that he's trying to get information from a bunch of morons.
Deltaman:
I apologize for assuming that you are setting up a commercial operation.
Also, I have no doubt that you can understand a proper bridle setup from information that's handed to you over the internet.
I just meant to say that you could learn much more about aerotowing hang gliders with a visit to Florida.
Yeah. Right. Name ONE THING.
I will leave this thread to Jim and Blindrodie, because they're truly helping Deltaman.
Yeah. Right. Two total shitheads named Jim. What more could you possibly ask for?
Dennis Wood - 2011/04/05 01:17:14 UTC
Suffolk, Virginia

i wonder how many tows are performed at the Florida parks each year. probably a lot.
Davis Straub - 2011/04/05 01:18:35 UTC

Many thousands.
Tens of thousands if you count the stuff in which the weak link blows before the dolly starts moving.
deltaman - 2011/04/05 07:30:44 UTC

before to leave, could you just list which important items I will learn in a flight park?
Thanks
Oh, DO let me handle this one, Bart.

Let's start with Wallaby, "the first and largest Aerotow Hang Gliding Flight Park in the World!"
Aerotowing is a system in which an ultralight aircraft (called an aerotug, or just a "tug") tows you and your glider aloft. For launch, your glider sits on a specially designed rolling cart. This cart supports your glider at the correct attitude for liftoff, and stabilizes it until you reach flying speed. You will already be prone before you begin rolling, making failure to hook in almost impossible. (Your harness should remain unzipped, however, in case you have to land immediately, due to weak link failure, rope break, etc.)
Yeah. DEFINITELY be prepared for weak link failure at EVERY stage of the tow. And keep your harness unzipped. Don't even THINK about rolling it in on the wheels WHEN it blows just as you're coming off the cart. True, it would be a million times safer to do it that way but then you wouldn't be practicing for when you need to land in a narrow dry riverbed with large rocks strewn all over the place or a field filled with seven foot high corn.
The release handle is Velcro-mounted on the lower control frame.
Yeah. Velcro. I believe that's the way the manufacturers mount brake levers to the handlebars of your kid's bike 'cause they don't wanna take any chances with anything as important as little Billy's safety.

And, of course, by "lower control frame" they mean "downtube" 'cause it's pretty tough to velcro a brake lever to the basetube without taking your wheels off. And even if you don't use wheels it just works better on the downtube 'cause there's less bend in the cable and it's neater and more out of the way there.
BHPA Technical Manual

On tow the Pilot in Command must have his hand actually on the release at all times. 'Near' the release is not close enough! When you have two hands completely full of locked-out glider, taking one off to go looking for the release guarantees that your situation is going to get worse before it gets better.
Oh, BULLSHIT. If that were true how come the first and largest Aerotow Hang Gliding Flight Park in the World doesn't say anything about it? How come their tandem training gliders have the levers on the downtubes?
A weak link connects the V-pull to the release, providing a safe limit on the tow force.
Yeah. It makes absolutely no difference what the rating is in terms of pounds or Gs - as long as you have A WEAK LINK nothing bad can possibly happen to you.
If you fail to maintain the correct tow position (centered, with the wheels of the tug on the horizon), the weak link will break before you can get into too much trouble.
See? No freakin' way can you get into trouble as long as you're using a weak link. I don't even know why they insist upon teaching people to fly before they start towing them up solo.
Your angle of attack should be high relative to the ground.
Yeah, you can always tell what your angle of attack is by looking at the horizon. Nose up - high angle of attack. Nose down - low angled of attack. Simple.
The three most common mistakes for pilots new to aerotowing are:

1. The pilot comes off the cart and rises too quickly above the tug, breaking the weak link.

2. The pilot fails to anticipate the tug's quick climb-out after launch, gets low, and then doesn't push out far enough to climb up. Remember: it is almost impossible to stall under aerotow. The induced thrust vector makes the glider trim at a higher attitude. It is OK to push way out; you will climb, not stall.

3. Over-controlling and over-correcting. Make only small, relaxed, conservative movements and corrections. Should you find yourself low behind the tug, you may need to actually push out on the control bar forcefully, resulting in a "past normal" bar position, that in non-towing situations would lead to a stall. However, because of the "pull" of the tow line, this action will result in a CLIMB, and not a stall. Stay with the tug using pitch input. If you are low, PUSH OUT!
Now this part might be a little confusing so let me help you out.

1. You might think that a weak link which blew when you were above the tug could leave you in an dangerous stall. It won't and can't. Remember the fundamental rule on weak links:
The weak link will break before you can get into too much trouble.
So if the weak link blows if you get too high above the tug you will ALWAYS have enough altitude to recover.

2. You also might - very understandably - be concerned that a weak link which could blow when you were high on tow could also blow if you were low and slow behind the tug and pushed way out, thus leaving you in an extremely dangerous stall.
We're the aerotowing (or "AT") professionals; no-one knows AT like we do; it's all we do, and we do it everyday, year-round.
These guys are the AT professionals, no one knows AT like they do, it's ALL they do, and they do it every day, year round. Do you think they'd tell you to do something that was dangerous?

Again, you gotta understand the fundamental rule on weak links:
The weak link will break before you can get into too much trouble.
You can't get into too much trouble by pushing way out when you're low and slow behind the tug because if you could the weak link would've already blown. Got that? What could be simpler?
The weak link is designed to act as a fuse, breaking the circuit when overloaded. In an excessive out-of position situation, the weak link will snap before the control authority of the glider would be lost.
Starting to get this now? As long as you're using a weak link you're ALWAYS gonna have the necessary control authority. It's IMPOSSIBLE to be locked out or stalled. The weak link thus makes being on tow a hundred times safer than free flight. I don't know why anybody even exposes himself to that risk by pinning off.

OK, let's check out Quest...

Quest is twenty-one and two thirds miles to the north-northwest of Wallaby so aerotowing functions under somewhat different principles.

http://www.questairforce.com/aero.html
Aerotow FAQ
WARNING the following information is a general overview of aerotow equipment, launch and flying techniques and emergency procedures and is intended to be used in conjunction with professional USHGA certified instruction. Do not attempt to aerotow without certified instruction!

The Launch - Technique - Emergency Situations

Equipment and Accessories

Releases

There are numerous ways to set up releases when aerotowing, but we've come up with only two methods, which aren't inherently problematic.

Double Release: The more popular method implements the use of two releases, a primary and a backup. The primary release is attached to the keel and has a cord or cable which runs down to a remote release handle at the bottom of the downtube or one side of the basetube. The backup release is a simple, reliable release attached to the aero tow loop on one of the harness shoulder straps. A V-pull is run between the secondary release and the other shoulder strap. A long bridle (about 8-10 feet long) is attached to the primary release with a weak link (more on this later), passes through the tow ring on the towline and then loops over the V-pull.

Single Release: The other method is the use of a single release (something simple like a reliable Bailey release) which is attached to one of the harness shoulder straps. The advantage of this method is the simplicity of having just one reliable release that, by not having to incorporate a long bridle, reduces the possibility of the bridle hanging up on the tow ring. The main disadvantage, and the reason this method is rarely used today, is the high amount of pulling in required to keep the glider down in position behind the tug. The use of a single release is definitely not recommended when flying a glider with heavy pitch pressure. If the single release method is used it is strongly recommended to place the weak link on the tow loop opposite the loop that has the release.

It's important to note that the position on the keel where the primary release is attached has a large effect on the trim of the glider during tow. If it is positioned too far forward on the keel, you'll find yourself constantly having to push out to stay in the proper position behind the tug. If the release is positioned too far back, you'll be having to pull in a lot. When positioned properly, you should be able to tow almost hands off. All gliders vary in the proper position, but usually the position will be at least 4-6 inches in front of the main hang point, and sometimes with single surface gliders as much as 2-3 feet in front of the main hang point. It is very important that the primary release be securely attached in such a way as to prevent it from changing position with respect to the hang point. A good method is to tie a strong line behind the king post and then run it forward and wrap it around the keel and tie it off again at the appropriate position.

It's also important to note that when attaching the primary release system to the downtube, enough slack should be left in the cable housing so that when the towline is pulled tight the housing stays loose. If the housing should ever pull tight, it may cause the release to inadvertently open.

There are a variety of safe, high-quality primary and backup releases on the market, but we've come to the conclusion that, when using the two-release method, the release that is attached to the keel should be the PRIMARY release - the first release used. The shoulder release should only be used as a backup. The reason for this is that sooner or later, the long bridle may wrap around and snag on the tow ring. If you had used the primary (upper) release when this happens, you'll find yourself suddenly being towed solely from your shoulders, and this is no big deal. Like explained above, being towed by the shoulders is a standard method. Pitch pressure will suddenly increase and it will be necessary to pull in quite a bit more, but the situation will remain controllable and now you can simply use the shoulder release to disconnect from the towline. If, however, you had used the shoulder release first, and the bridle snags on the towline, you will suddenly find yourself being towed solely from the attach point on the keel, and this IS a big deal. This is likely to cause the nose of the glider to pitch down violently, and common sense tells us that this is not such a good thing.

Weak Link

The strength of the weak link is crucial to a safe tow. It should be weak enough so that it will break before the pressure of the towline reaches a level that compromises the handling of the glider but strong enough so that it doesn't break every time you fly into a bit of rough air. A good rule of thumb for the optimum strength is one G, or in other words, equal to the total wing load of the glider. Most flight parks use 130 lb. braided Dacron line, so that one loop (which is the equivalent to two strands) is about 260 lb. strong - about the average wing load of a single pilot on a typical glider. For tandems, either two loops (four strands) of the same line or one loop of a stronger line is usually used to compensate for nearly twice the wing loading. When attaching the weak link to the bridle, position the knot so that it's hidden from the main tension in the link and excluded altogether from the equation.

IMPORTANT - It should never be assumed that the weak link will break in a lockout.
ALWAYS RELEASE THE TOWLINE before there is a problem.

Launch Carts (dollies)

The features of a good launch cart include the following:

The front two wheels are pneumatic, castering, and of a sufficient diameter to provide for the given terrain.
The basetube supports are adjustable enough to account for different gliders and the framework is open enough so that there is no chance the wheels on a glider can become wedged to the cart.
There is some way to hold onto the cart during the rollout (loops or a rope running the length of the basetube). The hold down loops or rope should be installed so that they cannot inadvertently hook on the glider, harness, or pilot.
The keel mount can be adjusted to set the proper angle of attack on the glider.

The angle of attack should be set in about the same position as minimum sink or stall would be in normal flight. As explained in Dennis Pagen's "Towing Aloft", when hanging freely from the glider in the cart, the basetube should be even with the pilot's forehead. It's better to have the angle set too high rather than too low. If the angle is too low, the glider won't leave the cart or may even want to dive in. Too high, and the glider is more likely to leave the cart in an unleveled attitude.

The Towline

The towline is attached to a release on the tug (so that the pilot of the tug can release the glider at any time) and is fitted with a tow ring on the glider's end. It's better if the tow ring doesn't have any jagged edges to prevent the long bridle used in the two-release method from snagging. A teardrop shaped tow ring can greatly reduce the chance of this happening.

Various aerotow parks use different length tow lines, but generally, the towline should be between 150 and 300 feet long. A short towline is generally better when the launching area is short or tight turning is required on tow. The glider also responds quicker relative to the tug, though the cone of workable positions behind the tug is smaller and reaching the point of lockout is easier. A long towline allows the pilot to get further out of position without locking out, though in thermally conditions, it can be more difficult to stay in proper position.

The Launch

Hang Check

Angle of the glider on the cart is correct (pilot's forehead even with basetube).
Hooked into main and backup hang loops.
Carabiner locked.
Harness lines clean.
Leg loops on.
Helmet chin straps latched.
Top release (if using one) is fully closed and there is slack in cable housing.
Weak link is in good condition (not frayed) and is proper strength.
Secondary (bottom) release is fully closed.
Basetube is clear, VG cord is stowed, and hold downs and glider wheels are free.
Wheels of cart are straight.
Towline runs straight to tug (not wrapped around tail of tug).
Air traffic is clear.

Rolling Out

Make sure the wheels of the cart are straight so the cart doesn't veer.
Have a secure grip on the launch cart hold downs.
Keep your arms rigid just when the cart begins to roll and then relax (the force of the towline can pull you forward too far and possibly nose the glider in).
Focus on the tug.
When you feel the glider just begin to pick up the cart, release the hold downs.
Maintain your altitude at about 10-15 feet by pulling in, and wait for the tug to climb.
Be prepared to let out on the bar the moment the tug's wheels leave the ground.
Follow the tug (maintain an attitude so that some part of the tug is on the horizon).

Special Situations

Cart Veers: If the cart does begin to veer for whatever reason, DON'T hold weight shift to try to straighten the heading. This won't change the track of the cart one bit, but it could very easily cause the glider to launch in a turn. Instead, use a bump-shift method to shift the cart. Lead with your body the way you want the cart to go and then jerk the basetube to pull the cart with you. It's not a big deal to launch with the cart veered a bit to one side, but it can be a big deal to launch without a wings level.

Prop wash: When flying with an especially high wing loading (like tandem) or using a short rope, you may hit the tug's prop wash on launch. You'll generally punch right through it with very little effect on your heading. Don't overreact but be prepared to make a correction if necessary.

Weak Link Breaks: This is one real good reason to launch with a little extra speed. If the weak link breaks right off launch, pull in immediately to avoid a stall but be prepared to flare hard to avoid diving right into the ground. If things get a little hectic, staying prone and rolling in on the wheels is an option.

Turbulence or Crosswind: Stay on the cart a bit longer in these conditions so that you'll have good maneuverable speed the moment you lift off. You may need it. Don't come off too soon. If you push out to try to lift off quickly, the glider may easily drop a tip or mush back into the ground.

Technique

Positioning

Though it varies from flight park to flight park, the general rule of thumb is to keep some part of the tug on the horizon. At Quest Air, we keep the wings on the horizon - this puts the glider slightly higher than the tug and gives you a slight head start when the tug hits lift. If the tug hits sink and/or suddenly drops, it's easy enough to pull in and quickly get down with little risk of breaking the weak link, but if the tug suddenly climbs, there is only so much or so fast you can push out without losing maneuverability or breaking it. This is why it's usually good to err on the side of being slightly higher than the tug, especially on launch.

Too High: If you get a lot higher than the tug, you'll be pulling the tail of the tug up and causing it to dive. This is about the scariest thing you can do to a tug pilot on launch (it is possible to pull him right back into the ground). If this happens, you'll almost certainly "get the rope". Remember: error on the side of high, but don't overdo it.

Too Low: If you find yourself low on launch, the tug can leave you in the dust, or more specifically, in the prop wash. In this situation, if you find yourself having to push out severely, it's better just to release from the line, land, and try it again. When you're close to the ground, you don't want to risk breaking the weak link, or worse, losing control and locking out. If you're at altitude and you find yourself low there is no immediate need for concern. Stay on the line and gently push out, and you'll eventually climb back up to the tug. An abrupt pivot is a good way to snap the weak link.

Banked Away From The Tug: This is the most critical thing to stay on top of, and if not corrected, can rapidly become a lockout. There is a fairly large window (a cone) of workable tow position, but once you've exceeded this boundary, the pressure to sling you away from the tug can become overwhelming. This is what is known as a lockout, and you want to release before you feel this pressure begin to build, especially when at a low altitude. Always correct for roll first and adjust your height second. For example, if you find yourself low and banked away from the tug, get your wings level and pointed at the tug first, and push out to climb back up on the tug.

Handling The Glider (avoiding oscillations)

Proper Form: Aerotowing can be very conducive to pilot induced oscillations, but it's a fairly simple matter to learn how to avoid them. Staying relaxed and having good form become very important. Since being on the towline gives you a lot more leverage by which to control the hang glider, it becomes very easy to yaw the glider. If, for example, you pull your shoulders to the right, you're really yawing the glider to the left, most likely the opposite direction from where you want to go.

The solution to this problem is actually real simple. Don't lead with your shoulders. Lead with your hips and legs. There are several ways to look at this, though they all say the same thing:

Pull your hips to the wing.
Pull the wing to your hips.
Steer the glider like a bicycle or a shopping cart.
Slide the base tube side-to-side, keeping it perpendicular to your body.

You'll find if you're using correct form, your head and shoulders will remain centered in the control frame, even though the towline may be attempting to pull them to one side or the other. If you continue to lead with your shoulders, the glider will yaw and most likely lead to oscillations.

Making Corrections: You'll find you generally have a lot of authority (when using proper form) to bank and/or level the wings on tow. This is because you're flying fairly fast on tow (usually 30 mph or more). Therefore, it is rarely necessary to pull in when making a correction. Of course, if a thermal got one wing and you need that extra bit of authority, pulling in can help. Because of this extra authority, it is easy to over control. The following outlines a good technique to make a correction without over controlling:

Maintain a constant roll command (use your hips not shoulders). DO NOT use the bump method. Continue holding constant pressure until you see that your command is working (the high wing is coming back down and the tug is beginning to drift back in front of you).
Now that the situation is back under control, you can gently bring the glider back into perfect position behind the tug if it isn't already there.
If you continue holding the roll command until the tug is directly in front of you, the glider will continue to roll past it and you will find yourself heading away from the tug in the other direction. This is an oscillation caused by over controlling (different than the oscillation caused by leading with your shoulders). The key is to only make a correction if you're heading off course. Otherwise, just relax and let the glider fly.

Turning on Tow

When the tug makes a turn on tow, you want to follow the same path through the air that the tug makes. This requires that, once the tug turns, you wait several seconds before you make the same turn. A real good cue to know when to start your turn is to wait until the towline begins to pull the nose of your glider in the direction of the tug. At this point, you do whatever is necessary to follow the tug's path. You'll find that very little input is actually needed.

Too far inside: If you begin your turn too soon after the tug begins its turn or if you bank too steeply when you do follow it's turn, you will find yourself on the inside. This will cause you to slow down and get low. If this happens, just coax the glider back into the tug's flight path. If you correct too quickly, or you may find yourself overshooting and possibly locking out to the outside of the turn.

Too far outside: If you begin your turn too late or if you don't bank enough, you will find yourself on the outside of the turn. This will cause you to speed up and get high on the tug. It is very easy in this situation to "get slung off" to the outside - a lockout.

If you have to error on one side or the other, it is better to err on the inside - especially when at a low altitude. This way, you're not in as much danger of locking out. Keep in mind, though, that if you're too far on the inside, you will get low and slow - control will become sluggish and you may stall.

Emergency Situations

Weak Link Break (or premature release)

Always be prepared for a weak link break or premature release from the towline and if it occurs pull in immediately to prevent a stall and, if you're low, focus on pulling off a good landing. If a release occurs right off of launch, just continue to fly straight ahead and roll in on the wheels if there's no time to get upright.

If you're launching from a short field, and you release too late to continue to fly straight without coming to the end of the field, immediately turn back towards the field and assess your options. If you're too low to pull off an approach and come around into the wind, you'll either have to pick a direction which allows you enough space to land crosswind, or in a worst case scenario, land downwind. It's always better to land downwind than to hit the trees. Again, landing on the wheels may be a good option.

You Get The Towline

If the tug pilot released you and gave you the towline or if the towline simply broke, use your release and get rid of it. If you're high when this happens, try to drop the line over the field so it can be retrieved, otherwise, just get rid of it. It is clear that trailing 240' of towline over the basetube is very hazardous.

Release Failure

The thing to do in this case is to follow common sense. If you are using two releases, use your second release. If this fails or you are flying with only one release use your hook knife to cut the tow bridle or V-pull.

Lockout

A lockout happens when you reach the boundary of that cone of workable positions behind the tug. It can happen real abruptly if you are banked steeply away from the tug, especially if you are on the outside of a turn, or it can happen slowly if you are gradually banking away from the tug. In either case, the important thing is to have the awareness of how far you can go before you can't get it back. In a gradual lockout situation, you can feel the pressure required to roll level becoming stronger and stronger until you can no longer fight it. If this happens low, DON'T TAKE A CHANCE-GET OFF! You should release before the situation ever gets to this point.

Don't ever risk locking out when you're low! If you find yourself banked away from the tug and you can't immediately get it back - USE YOUR RELEASE AND GET OFF THE TOWLINE. Don't ever count on the weak link to break or the tug pilot to hit his release.

2001-2004 Quest Air and Dean Funk Designs
There are numerous ways to set up releases when aerotowing, but we've come up with only two methods, which aren't inherently problematic.
Yeah, right. None of your shitrigged releases and methods are problematic when everything's going right.

Let's see how some of this works on a "training" flight at altitude under "controlled" conditions which terminates in tandem pilot certification.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3107
I have a tandem rating!!!
Lauren Tjaden - 2008/03/23 22:20:15 UTC

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

Anyhow, the tandem can indeed perform big wingovers, as I demonstrated when I finally got separated from the tug.
When Jim got me locked out to the right...
You were locked out? How could you possibly be locked out? At Wallaby:
In an excessive out-of position situation, the weak link will snap before the control authority of the glider would be lost.
One can only conclude that you weren't using a weak link. Try to take care of that next time.
...I couldn't keep the pitch of the glider with one hand for more than a second (the pressure was a zillion pounds, more or less)...
But, hey, it's OK to have the lever on the downtube instead of where those limey BHPA faggots tell you to put it 'cause you've got tons of altitude and maintaining pitch control DOESN'T MATTER.
...but the F'ing release slid around when I tried to hit it.
WHOA!!! Who coulda seen THAT coming! A bicycle brake lever firmly velcroed onto anodized aluminum tubing and it doesn't stay put? Well I guess you'll be filing an incident report with USHGA so they'll put out an advisory and get this little problem taken care of before somebody gets killed.
The barrel release wouldn't work because we had too much pressure on it.
NO WAY!!! Something simple like a reliable Bailey bent pin release and it WON'T WORK under just a QUARTER of the tow "pressure"? I'm sorry, I simply cannot accept that this happened. You must've mistaken something else for the Bailey in the heat of the moment.
Anyhow, the tandem can indeed perform big wingovers, as I demonstrated when I finally got separated from the tug.
GREAT!!! That must've been SO FREAKING COOL!!! How high were you when you started trying to pry yourself loose from the tug and how high were you when you finally get the glider back under control?
If the single release method is used it is strongly recommended to place the weak link on the tow loop opposite the loop that has the release.
Well what happens if that weak link blows and the bridle doesn't clear the tow ring? Will something simple like a reliable Bailey release handle unlimited tension? Eh, what do I know - you guys are the pros.
It's also important to note that when attaching the primary release system to the downtube, enough slack should be left in the cable housing so that when the towline is pulled tight the housing stays loose. If the housing should ever pull tight, it may cause the release to inadvertently open.
Did ya ever think about just building it into the downtube - like they do for the VG system - instead of fucking around with all that cable and velcro bullshit? (Yeah, I know, I coulda stopped after the first four words of that sentence.)
There are a variety of safe, high-quality primary and backup releases on the market...
Then how come you're using and selling the moronic shitrigged garbage that would've killed Lauren five times over in a REAL situation?
...but we've come to the conclusion that, when using the two-release method, the release that is attached to the keel should be the PRIMARY release - the first release used.
Oh. YOU've come to the CONCLUSION that it's not a great idea to risk being towed from the keel only. Wow. How long did it take you to CONCLUDE that? Have you reached any CONCLUSIONS about the advisability of whipstalling a glider at a hundred feet?
This is likely to cause the nose of the glider to pitch down violently, and common sense tells us that this is not such a good thing.
Are you REALLY SURE? Do we really wanna rely on COMMON SENSE? Hey! I've got an idea! Why don't we send Jim Prahl up on a Falcon to remove and doubt. And if he survives that maybe we can stuff a fifty pound sack of fertilizer into his left wingtip and send him off the ramp at Lookout to see what happens.
The strength of the weak link is crucial to a safe tow.
Yeah, right. When you're on a glider with a shitrigged release system the strength of the weak link is crucial to a safe tow the same way as when you're in a car with a shitrigged brake system the strength of the telephone pole and the reliability of the air bag is crucial to a safe drive.
It should be weak enough so that it will break before the pressure of the towline reaches a level that compromises the handling of the glider...
About how many pounds per square inch of towline pressure does it take to compromise the handling of a typical glider?
...but strong enough so that it doesn't break every time you fly into a bit of rough air.
Whoa!!! Now I'm really confused! The weak links that all you flight park assholes had me flying for all those years ALWAYS blew whenever I flew into a bit of rough air. Lotsa times they blew when I was flying in a bit of smooth air. Lotsa times they blow before the cart starts rolling.
A good rule of thumb for the optimum strength is one G...
Really? Who came up with that rule of thumb and determined it was good? Does a one G weak link blow before the pressure of the towline reaches a level that compromises the handling of the glider? Has anybody ever been on a towline with a weak link of under one G and had that pressure compromise the handling of the glider? Has anybody ever been locked out and slammed in with the weak link intact and the regulated pressure never exceeding a half G?
Most flight parks use 130 lb. braided Dacron line...
Well if most flight parks use it that's good enough for me. These people obviously really know what they're doing 'cause they do so much of it. It's not like the situation is such that a bunch of fucking morons are doing something just 'cause a bunch of other fucking morons are doing it.
...so that one loop (which is the equivalent to two strands) is about 260 lb. strong...
You've actually tested that, right? (Dickhead.)
...about the average wing load of a single pilot on a typical glider.
1. Let's say that the average wing load of a single pilot on a typical glider is 260 pounds.
2. You're putting a 260 pound weak link on one end of a bridle.
3. Wouldn't that limit the tow "PRESSURE" to 520 pounds?
4. Dickhead.
For tandems, either two loops (four strands) of the same line or one loop of a stronger line is usually used to compensate for nearly twice the wing loading.
The WING LOADING is the same.
When attaching the weak link to the bridle, position the knot so that it's hidden from the main tension in the link and excluded altogether from the equation.
Yeah, that way all you assholes can pretend that the weak link is twice as strong as it actually is.
IMPORTANT - It should never be assumed that the weak link will break in a lockout.
ALWAYS RELEASE THE TOWLINE before there is a problem.
So let's see if I got all this rot down...

The strength of the weak link is crucial to a safe tow but...

None of you assholes have ever tested it, you have no fucking clue what its actual strength is, you're too monumentally stupid to understand that if you put it on one end of the a bridle you double the tow tension, one G is a good rule of thumb but as CRUCIAL as the strength of the weak link is to a safe tow all gliders can be assumed to fly at 260 pounds despite solo flying weights spanning a range of two hundred pounds, and the weak link will blow before the PRESSURE of the towline reaches a level that compromises the handling of the glider but we can't assume it will blow in a lockout thus we should always release BEFORE there is a problem.

Do you guys just shit out of your ears or do you have some left over for the usual orifice?
A lockout happens when you reach the boundary of that cone of workable positions behind the tug. It can happen real abruptly if you are banked steeply away from the tug, especially if you are on the outside of a turn, or it can happen slowly if you are gradually banking away from the tug.
Can a lockout happen when you're trim, level, and lined up perfectly behind the tug so fast that no human can react to it before his glider's standing on it's ear?

Now let's check out the pros at Florida Ridge who also use the magic Quest weak link that puts all gliders at one G which is a good rule of thumb...
Rafael Castro - 2008/05/23 19:52:57 UTC

We all watched his weak link break, it was non-event something that happens all the time...
Axel Banchero - 2008/05/22 04:19:39 UTC

Doc's body wasn't moving and we were shitting our pants until he started talking confused. The first thing I saw was his eye bleeding and swollen the size of an 8 ball. There was sand and dirt inside. Looked like he lost it at first until he could open it a little bit.
Davis Straub - 2011/04/05 14:00:25 UTC

The flight park procedures here at Quest Air are the result of years of evolutionary pressures and experience that provide the focus on safety. The practices here illustrate what is important.
Bull fucking shit. In 1991/08 during the Dragonfly promo tour they had a pretty good cheap primary release consisting of a panic snap on the top end of the cable and a loop on the basetube on the other. Then these douchebags figured out five modifications they could make to get it really lethal and ten times as expensive.

And let's not forget the bent pin jobs.
The construction of the carts (materials, wheel rake, tightness of the axles, etc.)
Like the ones they were using twenty years ago which worked just fine? Like the carts the Danes were using in 1983?
The length of the tow lines.
Like the ones conventional gliders have been using for ninety years?
The appropriate carabineer.
WOW!!! I'm speechless. Now we can use long thin shitrigged bridles and NEVER worry about a wrap. We can use Quest primary releases and forget about releases and weak links below the carabineEr.
The launch procedures (signals).
AMAZING. They had to develop a whole new visual language 'cause the evil sailplane people wouldn't let us use theirs.
The maintenance of the 914 tugs.
And fashioned their very own tools out of Woolly Mammoth tusks and sinews.
The weaklink strength...
Yeah. 130 pound Greenspot.
- Puts all gliders at exactly 1.0 Gs - the perfect rating - no matter whether it's installed on a two or one point bridle.
- Never blows when you don't want it to.
- Always blows before the pressure of the towline reaches a level that compromises the handling of the glider.
...and construction of the connection to the tug.
WHAT??? It's a fucking rope running from a pole through a ring and down to a release. And they ever managed to botch that by making the pole too weak and...
I witnessed a tug pilot descend low over trees. His towline hit the trees and caught. His weak link broke but the bridle whipped around the towline and held it fast. The pilot was saved by the fact that the towline broke!
...being too fucking stupid to put weak links at both ends of the bridle.
The glider angle in the carts.
Again... Words escape me.
deltaman - 2011/04/05 14:06:20 UTC

Thanks,

So now I know I can stay in France :)
And - for the love of Jesus - if you DO go to Florida don't drink or eat ANYTHING these assholes do.
deltaman
Posts: 177
Joined: 2011/03/29 11:07:42 UTC

Re: Releases

Post by deltaman »

Thanks Tad to reply.
It will take few days before to read everything. It's close to be an encyclopaedia in 12 Vol !
If you don't mind, maybe you will accept to answer some specfic questions you surely did before.

I'm convinced with your "protow" release with straight pin and small and thick bridle. I will do one.
With it, do you use weaklinks on the both side too in a "1 point" and "2 points" use ?
Do you use a specific rope friction-proof as a bridle ? or is it useless ?

You seem to be really confident with weak link you selected.
Even if I clearly understood the snag pb and the bent pin pb of Bailey's, I'm still scared to have weaklinks on my shoulders as it could blow with V-bridle in tandem (even if they are well calculate as they could be weakened by friction if you don't change them every flight).
In the event of a snag I would be towed by the keel. And in this configuration I don't understand how a weak link there would instantly blow, as a normal tow tension is 15kg, far lower than the strength of the wl, except maybe by the 'jerk' of re-tension ?

So, in a "2 points" you use 3 or 4 wl?: one on the apex (?), one on the primary release and 2 on shoulders at each end of the bridle. Is that right ?

Which one you will advise to change every flight?

May you give me the equation to calculate the 1G weaklink with a sixty degree angle, please ?
fully loaded Wills Wing Falcon 3 Tandem flies at 571 pounds (PTV=259kg).
Although I like a weak link of 1.5 Gs, due to probable limitations of the tug and its release I'd say you can get away with a one G weak link.
Assuming you have a primary bridle long enough to form a sixty degree angle at the tow ring you need a 328 pound (149kg) weak link at the top of your bridle.
Below your tow ring you need a weak link 1.2 times that - 394 pounds (179kg).
A barrel release on your shoulder will be feeling half that - 197 pounds (89kg).
Could you explain me that:
Below your tow ring you need a weak link 1.2 times that - 394 pounds (179kg).
Which step (in G) seems to you significative for weaklink breaking load difference ? 0,2 ?..

How do you manage the different weight of passengers. I fly a T2 from North Wing with front and rear wheels and a keel extension. I'm 62kg and already took passengers from 50 to 110kg ! Do I have to change the 4 wl every flights ? Or which margin you would accept as you seem to accept some: you usually prefer 1.5G wl and tell me ok for 1G.

Actually (shame on us) we only use a 144kg tested wl on the apex (and one more stronger on the tug side (maybe 50% stronger as I don't exactly remember (I know it's bad)). No different one and no more elsewhere..

What is your opinion on a release in the apex of a V-bridle rather than the 2 releases system ?

I understood you are against carabiners. About snagging event, which difference you see with a small carabiner and a standard ring ? (except the risk to catch a front wire)

Does the 'top of a bottle' cut (the one which protect the wl on the apex below the ring) protect against a snag ? and front wires against carabiner ?
I have to organize a comp in my flatland and we need a quick system to catch bridle of each pilot.. What do you suggest (sorry for the win-win consideration).

PS: I'd like to accept your help to work on setting an easy primary release as VG system but I need more time than actually..

That's all for today.. Thanks++
Last edited by deltaman on 2011/04/06 18:58:59 UTC, edited 1 time in total.
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Releases

Post by Tad Eareckson »

----/--/-- - Peter Birren
1999/02/27 - Rob Richardson
2004/06/26 - Mike Haas
2004/07/-- - Litespeed aerotow, Germany
2004/08/02 - Davis Straub
2005/05/29 - Holly Korzilius
2009/01/03 - Stephen Elliot

Those are seven crashes - four of them fatal, two of them unfortunately not fatal - that very probably to definitely wouldn't have happened minus the flight park procedures there at Quest Air and other idiot tow operations which resulted from years of evolutionary pressures and experience that provided the focus on safety following the 1991 Dragonfly promo tour.

2005/09/03 - Arlan Birkett / Jeremiah Thompson
2008/05/18 - Socrates Zayas

Take Quest's weak links - the ones which will break before the pressure of the towline reaches a level that compromises the handling of the glider - out of the equation and the tandem guys live and go home smelling like roses that night, DocSoc doesn't get a concussion, and tens of thousands of minor to serious incidents don't happen.

I defy anyone to cite ANY SIGNIFICANT POSITIVE EVOLUTIONARY DEVELOPMENT in towing to come out of a US flight park in the past twenty years.

Antoine,

Thanks for posting. I'll get back to you on all that as soon as possible.
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