ALL release mechanisms - 'cept for the Linknife which keeps working MORE effectively with increasing tension but has other issues which disqualify it - benefit from reduced load. They require less actuation force and can be built smaller, lighter, cleaner, simpler, cheaper.
My barrel releases wouldn't handle the full towline tension at a safe weak link rating but there's nothing I'd change for one point if I could.
Oh, so "splitting the tension with a bridle" solves the problem.
Yeah, it would bring the load issue to an acceptable resolution.
Wrong tool for the job.
On that issue (cable) it's the adaptation that was wrong. Shoulda left it like:
Funny, I thought it was "designed" to be used to release a spinnaker sheet, not a hang glider.
Tons of stuff found on hang gliders is designed to be used on sailboats but is equally ideal for hang gliders - which are sailboats designed to leave the water behind. A spinnaker shackle is designed to dump a spinnaker sheet under tension. A spinnaker sheet is a rope. A tow bridle is also a rope.
And when his weak link snaps, bridle wraps, he's no longer weak link protected.
ANYONE can EASILY make a one point bridle short and fat enough such that a wrap is a physical impossibility. (But the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden, says to make it two to four feet long so nobody does.)
Lunacy is the name of the game in this sport. Kinda thought you would have figured that out by now.
I think we're making small dents. AND making life miserable for Paul Hurless. Win/Win.
There needs to be a bit more said about these issues.
Definitely - but not by you.
First, the spinnaker shackle pictured above is very widely used for aerotowing and used very successfully.
There's tons of crap you can throw up into the air that's "very widely used for aerotowing and used very successfully" damn near all the time. The bent pin shit you pump out and perpetrate on the public is very widely used for aerotowing and used very successfully damn near all the time 'cause damn near all the time you've got damn near all the time, altitude, and/or control to make it work and you're limiting the tension with dangerously and illegally light...
Personal opinion. While I don't know the circumstances of Frank's death and I am not an awesome tow type dude, I think tow releases, all of them, stink on ice. Reason: You need two hands to drive a hang glider. You 'specially need two hands if it starts to turn on tow. If you let go to release, the glider can almost instantly assume a radical attitude. We need a release that is held in the mouth. A clothespin. Open your mouth and you're off.
Some aerotow releases, including a few models from prominent schools, have had problems releasing under high tensions. You must VERIFY through tests that a release will work for the tensions that could possibly be encountered. You better figure at least three hundred pounds to be modestly confident.
Maybe eight to ten years ago I got several comments from people saying a popular aerotow release (with a bicycle type brake lever) would fail to release at higher tensions. I called and talked to the producer sharing the people's experiences and concerns. I inquired to what tension their releases were tested but he refused to say, just aggressively stated they never had any problems with their releases, they were fine, goodbye, click. Another person tested one and found it started getting really hard to actuate in the range of only eighty to a hundred pounds as I vaguely recall. I noticed they did modify their design but I don't know if they ever really did any engineering tests on it. You should test the release yourself or have someone you trust do it. There is only one aerotow release manufacturer whose product I'd have reasonable confidence in without verifying it myself, the Wallaby release is not it.
- Can or can it not handle six hundred pounds of towline tension?
I just kept hitting the brake lever for a few seconds in WTF mode...
- Are its chances of killing me zero or something a total moron would find acceptable?
It's kinda like my glider, Davis. I don't wanna fly it 'cause some stupid air jock tells me it's been "very widely used for aerotowing and used very successfully" - I wanna know whether or not it's passed HGMA and/or DHV certification testing.
To get this issue to be seriously considered...
Since when did you stupid motherfuckers start seriously considering ANYTHING? You only even make a pretense of it for a short time after somebody gets killed with lotsa witnesses around.
...and the use of a small ring considered...
- He didn't say a small ring. He said a ring...
...large enough to slide past the knob under all angles and situations.
- Considering the use of a ring is a really bad idea.
...much more information about Robin's bridle setup needs to be provided...
Robin's RELEASE setup sucked. It helped get him killed. What you total fucking morons need to do is look at setups that DON'T suck. But that would be way beyond your capabilities so just shut the fuck up and leave this action to people who don't have total shit for brains.
...and more discussion about how the weaklink worked needs to take place.
The weak link worked EXACTLY as it was supposed to. There was no overload situation so it held. It was one of the very few weak links that DID work at your moronic event.
Otherwise this recommendation from Rohan will just be ignored.
Yeah.
Doug Hildreth - 1991/06
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. Amazingly, there were minimal injuries.
Comment: This scenario has been reported numerous times. Obviously, the primary problem is the lack of pilot skill and experience in avoiding low-level, post-launch, nose-high stalls. The emphasis by countless reporters that the pilot lets go of the glider with his right hand to activate the release seems to indicate that we need a better hands-on way to release.
I know, I know, "If they would just do it right. Our current system is really okay." I'm just telling you what's going on in the real world. They are not doing it right and it's up to us to fix the problem.
Luen Miller - 1996/10
I am strongly recommending formal review and analysis of releases and weak link designs for all methods of towing by the Towing Committee, and that recommendations on adoption or improvements be generated.
I believe that from preflight through release we should have more standardized procedures in towing.
Like that would be a first.
Second, the same applies for the recommendation re the rope length. The issue of angles behind shorter ropes can be fairly quickly understood...
Not by Bill Moyes and Bobby Bailey apparently.
...but it needs to be presented in more detail.
Yeah. They should probably be talking millimeters instead of just meters.
Also, there needs to be a discussion of spectra vs. poly (inelastic vs. elastic...
Yeah.
Rodney Nicholson - 1986/11
Ontario Hang Gliding Association
In the third and most recent incident, the weak link broke shortly after launch and the end of the tow rope, with metal ring attached, whiplashed back and hit the spotter/winch operator in the eye. At present the chances appear 90% that he will lose the eye completely.
Obviously one of the dangers of an elastic towline is that when it breaks, it can spring back and hit the pilot with much force--I've heard of a (nylon?) towline actually breaking its way through the canopy and into the cockpit of a sailplane after it broke under a heavy load.
Gregg Ludwig - 2006/01/22 18:15:15 UTC
I just can not understand why operators continue to use poly towlines (for aerotow ops) when spectra towlines are clearly superior. Poly is less expensive... but when considering the cost of a tow plane and HG and the advantages of spectra, a few dollars of savings is foolish.
Gregg Ludwig - 2006/01/23 16:32:52 UTC
Towline elasticity produces a rubber band effect that results in ever changing towline forces that can also produce significant airspeed changes as well. Since Spectra does not offer elasticity (or very little) this effect does not occur and a safer tow results. Trikes normally tow with longer lines of 200-250 feet so the advantages of Spectra are even greater.
Let's discuss Spectra versus polypro a little more - asshole.
This matter is being given much thought.
It doesn't matter how much thought is being given if the people giving it are as incapable of thinking as they and you obviously are.
Could other towing groups please indicate how they handle it?
Try looking at how competent sailplane groups have been doing it for the past zillion years.
...and the affect...
Effect.
...on the weaklink) tow rope line.
As opposed to the tow chain line.
The EFFECT is that...
- No matter what you're using between the tug and glider - Spectra or bungee - the tension at one end is the same as the tension at the other end at any given moment.
- WHEN the planes get bounced around in turbulence the polypro will INITIALLY reduce the tension but at some point in the very near future there's gonna be a recoil and you'll be getting that tension back - quite possibly or, according to Murphy, LIKELY on top of what some more air will be doing to you at a very inconvenient moment.
- Thus your overall control of tension and thus the flight goes down the toilet when using polypro.
- And if you're some Davis caliber douchebag with an expectation that you can use a Local Rules precision weak link which will break as early as possible in lockout situations, but be strong and reliable enough to avoid frequent breaks from turbulence your moronic expectation will go down the toilet one helluva lot faster.
- And I don't know about you but I'm not real crazy about having 250 feet of elastic material stretched to three hundred pounds and aimed straight at my face when I've got some shithead at the front end of it who's vowed that he can fix whatever's going on back there by letting me have it.
Three, is Rohan saying that the pilot's weaklink should be 85% of 1 G?
Here's what Robin said regarding the recommendations that the douchebags running this incompetent lethal clusterfuck pulled out out of their asses after y'all splattered Robin:
Weaklinks shall be no stronger than one 'G', i.e. equivalent to the combined weight of pilot, glider and gear. This applies to the tug end as well. The glider end is best set at 15% weaker to avoid having the glider pilot fly with the rope in the event of a weaklink break at the tug end.
Regardless of which moron said what let's take a look at it...
Weaklinks shall be no stronger than one 'G'...
WHY?
- Compare/Contrast the damage inflicted upon gliders stressed to the breaking points of one and two G weak links.
- Express in:
-- degrees the extent to which gliders using one and two G weak links can get out of whack behind the tug before failure.
-- feet the required stall recovery altitude following lockouts which are permitted to progress to the failure points of one and two G weak links.
-- number of ribs broken by the times one and two G weak links fail following blown dolly launches.
-- feet the dragging distances permitted by one and two G weak links after blown launches.
- How much more killed did Robin get at the end of his lockout when his 400 - and Bobby's 230 - pound weak links held all the way to the ground than Mike Haas did at the end of his lockout after his 226 pound standard aerotow weak link blew at sixty feet?
- Express in degrees the extent two which gliders using one and two G weak links can jerk a Dragonfly tail sideways.
- How much more severely can a glider using a five hundred pound weak link stall into the ground a Dragonfly with an engine failure on takeoff than the glider using the 226 pound standard aerotow weak link stalled Dick Reynolds into the ground at Lookout on 1992/05/17?
This applies to the tug end as well.
What's the basis for that off-the-scale moronic statement? All of these brain dead motherfuckers tow two hundred pound little girl gliders and five hundred pound tandems. Are they swapping out their weak links between tows to match the flying weights?
The glider end is best set at 15% weaker to avoid having the glider pilot fly with the rope in the event of a weaklink break at the tug end.
Here's a thought - assholes:
FAR 91.309(a)(3)
(i) A safety link is installed at the point of attachment of the towline to the glider or unpowered ultralight vehicle with a breaking strength not less than 80 percent of the maximum certificated operating weight of the glider or unpowered ultralight vehicle and not greater than twice this operating weight.
(ii) A safety link is installed at the point of attachment of the towline to the towing aircraft with a breaking strength greater, but not more than 25 percent greater, than that of the safety link of the towed glider or unpowered ultralight vehicle end of the towline and not greater than twice the maximum certificated operating weight of the glider or unpowered ultralight vehicle.
The weaklink issue continues to be discussed heavily.
Yeah, the weak link is PERPETUALLY continues to be discussed heavily. That's 'cause hang glider jockeys are inherently too fuckin' stupid to understand or listen to the people who understand that...
Tost Flugzeuggerätebau
Weak links protect your aircraft against overloading.
...weak links protect your aircraft against overloading - AND *NOTHING* MORE.
The strength of the weaklink needs to be determined by many issues...
Fuck you.
...including, the wishes of the tug pilots...
Yeah Davis, let's base our aviation standards on the WISHES of the dregs who haul us up.
Dr. Trisa Tilletti - 2012/06
Actually, that is our expectation of performance for weak links on hang gliders here at Cloud 9, too. Primarily, we want the weak link to fail as needed to protect the equipment, and not fail inadvertently or inconsistently. We want our weak links to break as early as possible in lockout situations, but be strong and reliable enough to avoid frequent weak link breaks from turbulence. It is the same expectation of performance that we have for the weak links we use for towing sailplanes.
Let's throw in a few of their EXPECTATIONS as well.
One day I went to Ridgely with the expectation that my weak link would pull my glider off the car, set it up, preflight it, and carry it to the launch line for me. After about an hour and a half it suddenly dawned on me that my expectations were unrealistic. Try to learn something from my mistake.
...the weight and experience of the pilot...
- Two T2 154s. One hooks in at 185, the other at 285. What are the appropriate weak links and why?
- Hang Two and Five. Do you use a lighter weak link for the Five 'cause he's better at staying inside the Cone of Safety or a heavier weak link 'cause he can recover from a whipstall using less altitude?
If I put it on my Pro-Tow, then the tension on it is reduced by the cosine of the angle (results is =>300 lbs).
You're so fuckin' dense that that you think separating the bridle ends DEcreases the load on the weak link.
...the bridle type at the tug...
Yeah, if you're using a W bridle you should use half the strength you would for a V bridle.
...and the conditions at the launch area.
What weak link should you switch to after you climb above the launch area?
Idiot.
Too weak and too strong are both not so good.
Gimme too strong any day of the week. I don't go up with the same shit equipment you do and am thus able to blow tow in the unlikely event that I need to well before one of your shit Davis Links will do my job for me.
Fourth, Rohan said that when he examined Robin's bridle he saw that the weaklink was intact and around the leg of the shackle. What had been broken was the string holding the shackle to his chest and the wire cable that was used to pull the shackle open.
And you assholes let him go up with that?
I have asked Rohan a long series of questions...
What special qualifications does Rohan have? I'd suggest ANY sailplaning text but I doubt there are any available at a second grade reading comprehension level.
...and will have more on this.
I can hardly wait.
I feel that the best way that we can honor Robin, is to make sure that his death was not in vain.
That's funny, I feel the best way we can honor Robin is to keep launching gliders in the lanes NOT occupied by his warm but lifeless body and smoldering wreckage before the meet-heads decide that a review of procedures is needed and scrub the task.
Fuck you, Davis. There's nothing that makes you happier than making sure damn near ever death in this sport was in vain and we WILL get reruns at regularly scheduled intervals.
Regrettable to find these pages which are no longer state of the art. The spinnaker shackle is not to be advised as it doesn't release without tension.
If you use it as a two point release and configure it properly...
And if you get into a slack line situation - which you shouldn't 'cause it's a lot easier to avoid than a high tension situation - you can use two hands. And having two hands off the bar isn't much worse than having one hand off the bar - and nobody seems too worried about having one hand off the bar in lockout situation. And if you've got a slack line situation you're not in a lockout situation.
The Koch equipment has never failed as far as I know.
Mike Nooy's release was triggered but at the angle of the rope that was greater than 90 degrees to the 'finger' at its max open point, so the rope did not come off the end. The release 'finger' was mounted firmly to the front of the harness, as with all the H.S systems. We call them Euro tow systems.
The release 'finger' pivoted only horizontally and less than 180 degrees. The finger should be able to pivot vertically as well as horizontally and in excess of 180 degrees to release in any direction. It needs a UNI joint, like found on a car tail shaft but smaller and covered so it will not snag.
The other systems are less reliable (again tension problems).
Peter Birren - 2005/02/17
Fuck you, Peter.
We were able to make the spinnaker shackle hang up with relative ease.
And others have had the Linknife taken out of commission with no effort whatsoever - just exposing it to a bit of wheat stubble did the trick.
All it took was a twist or two in the weaklink line while putting it on the shackle.
Here's a thought...
Don't give a twist or two to the weak link line while you're putting it on the shackle. Probably a good idea to avoid kinking your sidewires as you're tensioning your glider as well.
We also got the Linknife to hang up. It took a particular figure-8 wrap with the pull string stuck under the O-ring to do it. Something that would be highly unlikely to happen, at least with a modicum of due diligence by the pilot.
We've been using Linknives here in Western Australia for many years now for both car and aero-towing. From thousands of tows there have been only a couple of release failures. These have been due to either the release line twisting around the Linknife, or wheat stubble becoming jammed in the "v" of the blades.
If you've got a choice between a system which requires a modicum of due diligence by the pilot and a much better system that DOESN'T requires a modicum of due diligence by the pilot then go with the latter.
This is my closed aerotow V-bridle with Linknife on weaklink at the bridle/towline junction:
And this is what happens when the shit's hit the fan and you need to blow it:
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.
Not interested, Peter. Go back to the fuckin' drawing board or take a look at the work of somebody who's done the job right.
Stuart Caruk - 2005/02/27
I'm pretty sure that we build one of the few sewn hang glider bridles.
- WHAT?
- What about hang glider RELEASES?
It was designed specifically for those who choose to foot launch hang gliders from the beach or shoreline.
Fine. People who CHOOSE to foot launch for tows obviously aren't terribly interested in safety margins so put them up on whatever crap you feel like.
People who - because of terrain limitations - hafta foot launch deserve better consideration than an asshole like you is ever gonna give them.
Most of these pilots used the aluminum block dual trigger style release and didn't want the hunk of metal on their chest. Almost all of these pilots choose to tow from the hips, with an attachment on either side of the harness that runs up through the hang loop.
Why not just anchor it to the hips?
I kept trying to find pictures of the standard glider tow release we used to use years ago when I towed aerial advertising banners. I did find a line art drawing of it though.
It's a Schweizer release.
Essentially the towline went through the space in the L shaped bracket. This bracket was held closed by tension on the pin created by the semi pyramid shaped rubber pyramid at the bottom above the pivot pin. A release cable was connected to the top, and when pulled, the L shaped arm flew back releasing the towline.
It wouldn't take much to whip out a few of these in a lightweight alloy if the demand existed. I'm not a fan of the spinnaker releases.
Yeah Stuart, it never takes much to whip out a few release mechanisms. Any asshole a couple of notches above Davis can do it. Designing and building is safe actuation system is a real bitch however and takes something in the way of brains to do it. And that's way over your pay grade.
Paul Voight - 2005/02/17
I have to admit on one occasion a few years ago the weak link got snagged on the little lip on a typical (Florida style) wishard release at the end of my tow (after opening/releasing the release).
Any chance that if you WEREN'T an irresponsible asshole and put out an advisory on this issue that Robin would still be alive?
It took more that a few moments to process the information ("that's odd.... I'm still being towed! Why??"). ((Tug pilot must think I'm an idiot. )
- Tug pilot would be right.
- Tug pilot's also an idiot or he wouldn't have towed you up on this piece of shit.
- So the fuckin' tug pilot immediately grounded this thing and put out an advisory, right?
I physically shook the bridal...
Did her veil come off? Did she scream in terror?
...but that didn't un-snag it. I located my hook knife with my hand, but then just decided to wang hard to break away, which worked fine.
Instant hands free release!!! Block off the old chip.
I can see how this situation would really suck, just out of the cart, or anywhere near the ground.
Ummm... If you're holding that much pitch pressure, popping the weaklink and flying away should be easy as blaming a fart on the dog.
Ryan Voight - 2009/11/03 00:14:35 UTC
if you're holding strong pitch pressure and let it out, I assure you the weaklink will earn it's name, and it will do so at a time of YOUR choosing. If you're banked/rolling off to the side as described, letting the bar out/nose up will only increase your rate if direction change, and it's not like you will balloon up and tailslide or anything dramatic like people like to talk about...
Ryan Voight - 2009/11/03 05:24:31 UTC
It works best in a lockout situation... if you're banked away from the tug and have the bar back by your belly button... let it out. Glider will pitch up, break weaklink, and you fly away.
During a "normal" tow you could always turn away from the tug and push out to break the weaklink... but why would you?
Have you never pondered what you would do in a situation where you CAN'T LET GO to release? I'd purposefully break the weaklink, as described above. Instant hands free release
Tad Eareckson - 2009/11/03 15:28:14 UTC
That's great advice for winning an aerobatics competition - and an almost sure fire recipe for getting a tow pilot killed instantly.
And you're TEACHING this stuff?
Ryan Voight - 2009/11/03 20:51:52 UTC
Coming from a guy who's username is aerotowing, yet has nothing good to say about it... that's pretty funny
We should go towing some time... I can teach you how to break weaklinks intentionally, before things get too bad... then you can show me how you put things in your mouth
My whole point is that people tend to "hang on" too long trying to save things, rather than recognize a bad situation and release (one way or another), go back, and reset.
I'm not saying wait until you're so locked out you're passed 90 degrees bank and then pitch up to break the weaklink and do half a loop into the ground. I'm saying get the hell off way before that, and if you can't let go you CAN pop the weaklink pretty easy... they're weak after all
I'm done with this thread. Went from a good discussion RE: one barrel or two, and became a "the sky is falling and towing is death" tyrade. If you don't want to tow, don't... let other's do what they want. Live and let live my friend.
Talk to your adorable little boy sometime. He can show you how to do it before things get too bad. Glider will pitch up, break weaklink, and you fly away. Easy as blaming a fart on the dog.
Since (and before) then, I've had many, many uneventful tows with those releases, but I concur that a ring would reduce the chances of release failure significantly.
What happens when the ring gets to the tow ring - asshole?
Ya know what you oughta do, Paul?
You should make a film on aerotowing safety and dedicate it to the loving memory of Robin Strid.
Rohan Holtkamp - 2005/02/17
No matter what type of weaklink material you use on this type of release (spinnaker shackle), it is only a function of twisting and tension to make the material become tight enough to not slide off the leg.
SO DON'T TWIST IT WHEN YOU'RE HOOKING UP YOUR BRIDLE.
Could you go into more detail about your push button truck tow release and the lanyard version you experimented with? I'm truck towing an awful lot lately and have yet to find a release that doesn't scare the heck out me.
Not a ten thousandth as much as going up with some piece of shit actuator "within easy reach".
In my opinion, the only part that should be in contact with this type of release must be something that cannot get tight. Use a metal ring, one that is large enough to come out every time, or use a different release.
- It won't clear the tow ring.
- How 'bout writing less and designing more?
- Or at least looking at what other people have done to address all these issues...
Not being constructive? There is one person who has put more thought and time into releases than anyone. That person is Tad. He explains the pros and cons to every release out there. I gave you the link to more release information than the average person could ever digest, and I didn't get a thank you. Just you bitching that we aren't being constructive. What more could you want? He has created something that is a solution, but no one is using it... apparently you aren't interested either. So what gives??? What do you want us to tell you? Your concerns echo Tad's concerns, so why not use his system? Every other system out there has known flaws.
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.
So to what tension did you test your bent pin beauties?
I use a 130 lb braided Dacron weaklink.
Why? 'Cause that's what everyone else uses? Same reason you used bent pins for your barrels?
Another variation is to add a Linknife with an orange pull-handle over the weak link.
- Why? No confidence in your barrels?
- What happens with that Linknife assembly when it gets to the tow ring after you've pulled your starboard barrel?
The orange handled Linknife hangs above the right hand on the control bar and can be released quickly.
Yeah Gerry, sure it can. Just as quickly as idiot fuckin' Paul was able to get to his barrel when the shit hit the fan. And just as easily as you can fight a lockout with one hand.
P.S. I really like the way you made your barrel releases as short as possible and your bridle as long as possible to give it as much chance of welding itself to the tow ring as possible. This sport just gets so boring unless you maximize your chances of killing yourself as much as possible.
(editor's note: I put my primary release at my right hand.
Like Gerry I've also used a secondary barrel release.
Why? I've always thought you were heavily into MINIMIZING survival option for yourself and the idiots who buy the crap you sell.
I use thicker spectra.
Oh really?
Oz Report's Useful Goodies
Pro tow Mini Barrel Release and Bridle, $40.
If you want two mini barrel releases (one on each side), order two of these (you'll have an extra bridle). Bridle is 750 pound Vectran.
This release won't accidently open by hitting your base tube, if you connect it to your chest tabs. It is small and easily stored. If you can't store it during flight, it is the most aerodynamic one available. The bridle is thin and gets out of your way right away. Easily stored. Also creates less drag if you don't put it away. Much stronger than your weaklink. I change bridles about once a year after about fifty tows. I've never had one break.
I've always preferred the thin stuff. It is thin and gets out of your way right away. Easily stored. Also creates less drag if you don't put it away. Much stronger than your weaklink. I change bridles about once a year after about fifty tows. I've never had one break.
What is shown here is thin enough that it might tangle when sliding through the ring or carabineer at the end of the tow rope...
Well yeah, but it is thin and gets out of your way right away. Easily stored. Also creates less drag if you don't put it away. Much stronger than your weaklink. I change bridles about once a year after about fifty tows. I've never had one break.
Oh yeah... an other fun fact for ya... ya know when it's far more likely to happen? During a lockout. When we're doing lockout training, the odds go from 1 in 1,000 to over 50/50.
Almost unimaginable in a normal situation and only a bit over a one in two chance of it killing you when the shit's hitting the fan. But let's talk some more about how dangerous the spinnaker shackle is.
I do not connect the weaklink to the end of the spectra that goes to the barrel release as pictured above. The pin (as indicated earlier by Bart Doets) in the barrel cuts through the weaklink.
What if you deburred the pin so it wouldn't? Just kidding.
Much better to put the looped end of the spectra in the barrel.
Much better.
And the chances of the bridle wrapping in a lockout after your Davis Link blows and subjecting your bent pin release to virtually unlimited tension are just a little over fifty/fifty.
Bobby's a fucking genius when it comes to this shit.
...who's a fucking genius when it comes to this shit, used a bent pin for his release. It's a lot easier to fold it over a thick loop of Spectra without a weak link on the end.
Bill Bryden, co-author of the excellent book, Towing Aloft, writes:
Bill Bryden - 2005/02/20
Rohan indicated in Oz Report issues 37 and 41, that the spinnaker style shackle release must be used with a metal ring to avoid weaklink entanglement with the leg of the release. This may be acceptable for situations where the release is connected to the towline directly. However, in the USA, most of these type releases are used in conjunction with a "V" bridle...
And here and there a "W" bridle..
...which attaches at the keel and to the pilot.
Thus a three point bridle, right Davis?
One end of this bridle is connected to the release and it then unthreads from a ring on the towline upon release actuation. If a small metal ring is connected to the end of this bridle to interface with the release, then the potential for entanglement of the bridle with the tow line while unthreading becomes quite high.
Duh.
In short, using a ring to address the shackle release deficiencies may well create a higher probability and possibly worse failure mode when used with unthreading V bridles.
May? Possibly?
This is not the first time release issues with these shackle style releases have occurred. There have been some that were very difficult to actuate when under higher loads.
But you motherfuckers didn't have any problem festooning your excellent book with photos and illustrations of them, telling us where to buy them, and telling us that we're all too fuckin' stupid to do any better so don't even bother trying.
And you motherfuckers have been perfectly OK with continuing to sell your excellent book with all this crap in it through USHGA and at the facilities that sell this crap.
The release in the shown here...
...avoids some of the issues the spinnaker shackle presents. This was sold in the USA by Lookout Mountain Flight Park for aerotowing but I don't know if they still manufacture this release presently.
No, that was a Schweizer knockoff so it woulda worked OK. It's subsequently been upgraded to the new and improved Lockout Mountain Flight Park Aerotow Release...
...which isn't warranted as suitable for towing anything. They just use it for selling to the tourists and use a spinnaker shackle on their tandems to minimize the chances of THEM getting killed along with their students.
Sadly, the whole issue with poor releases is not new. Other fatalities have occurred as well. In response to those, performance test procedures were published in Hang Gliding magazine over a decade ago and are listed in the appendix of the textbook Towing Aloft as well.
Performance tests which neither of you motherfuckers actually conducted on any of the bent pin crap with which you festooned your excellent book.
While those standards may certainly need modification for some applications, and I don't suggest they are near perfect, they were presented to prompt people to adequately consider the design rigor and testing that is needed during development and manufacture of these devices.
Yeah. Name two people who've actually DONE that.
If you useless sleazy bastards weren't the useless sleazy bastards you are YOU'd have conducted tests on this kinda crap and written a chapter telling people to avoid Wallaby, Quest, and Lookout junk like the fucking plague.
There is little excuse for many of the release failures that seem to still occur.
You sound like a goddam pimp decrying the evils of prostitution.
On the subject of weaklink strengths, people should note that all recommendations being tendered by anyone are essentially just guesses.
Ever wonder why in sailplaning you just get a manufacturer specified weak link that's about 1.4 Gs for surface and 1.3 for aero instead of a bunch of crap from people who have no fuckin' clue what they're talking about telling them that people should note that all recommendations being tendered by anyone are essentially just guesses?
Some may be more educated than average and some have clearly been less educated.
Maybe you could tell us which are which.
The right way to determine the weaklink recommendations would be to measure the tow line tensions for dozens of flights and pilots and perform a statistical analysis of them.
Moron.
I performed a good number of surface tows with a tension gauge at the glider to assess tow line tension. Unfortunately, I only performed a couple aerotows with the tension gauge in the system to determine if my tension hypotheses were in the ballpark before Dennis Pagen and I did the towing book.
You assholes had no fuckin' business doing a towing book. We'd be thousands of times better off if you hadn't and just referred people to sailplane texts.
I watched the gauge and didn't log the tensions with a data recorder. I don't know if actual tensions at the glider have ever been measured by anyone else.
I have.
I hope so but wouldn't be surprised if it never happened.
It's happened.
So, until a good data analysis occurs, no weaklink strength recommendations are gospel.
You're full of shit, Bill. Weak link strength doesn't have a goddam thing to do with normal tow tension. It has ONLY to do with...
Tost Flugzeuggerätebau
Weak links protect your aircraft against overloading.
...GLIDER CAPACITY.
And you've had over seven and a half years since you wrote this rot to engage in weak link discussions and figure out what the fuck you're talking about and you HAVEN'T. So fuck off. And tell your sleazy coauthor to fuck off as well.
I have no preference for the type of rope but rather for its qualities.
The ropes we provided were exactly 90 meters long. Bill's were around 60 meters. There is more time to release in an emergency with a 90 meter long rope as opposed to a 60 meter one.
Yeah, Bill's never been much into MAXIMIZING safety margins.
Poly stretches more than five percent. Spectra less than one percent. A little stretch is better than none to preserve weaklinks.
BULLSHIT.
- We're towing through AIR. Air has all the elasticity we need.
- A little stretch is WORSE than none to preserve weak links. You put stretch in the system you have shit tension control - it dips lower and peaks higher while you're yo-yoing around back there.
- If you wanna preserve weak links don't let fucking douchebag tug drivers dictate weak links on the ragged edge of sustainable tow. Make them one and a half Gs and forget about them.
- Why are we having a lunatic discussion about trying to protect fucking weak links when the job of the fucking weak links is to protect our fucking gliders? Get the goddam horse back in front of the goddam cart.
Have you tried towing a car with steel cable?
Yes.
Would you rather use a webbing strap?
Not with gas at four bucks a gallon. If you want an efficient tow eliminate elasticity.
If you allow the cable to go slack you can have a problem. But you don't wanna allow slack to develop between two cars and you REALLY don't wanna allow slack to develop between a tug and glider.
Poly is twisted...
Bullshit. You can get braided polypro.
...spectra woven.
Braided.
Poly twists under load when new, spectra does not.
Anybody who tows with polypro is an idiot. Andybody who tows with twisted polypro is a total moron.
If your release system does not cater to twist...
I'm trying to think of a sane release system that caters to twist. I'm not having much luck.
...is it a fault in the rope or the release? We use a swivel at each end when car towing to prevent any drama.
Wanna prevent drama? Use:
- minimum stretch materials
- one and a half G weak links
- releases that don't stink on ice
- drivers with fifty times the intelligence than the dickheads you had at Hay
Kevin Carter - 2005/02/21
I definitely didn't have a problem with long ropes. Even using them the first time it seemed fine to me. Seems like it has great potential with spectra.
Bill told me that they used the blue ploy rope way back in the early days of the Dragonfly. It was inexpensive so why not give it a go?
Yeah. Donnell didn't wanna spring for a controlled tension payout winch and figured that eighth inch nylon parachute shroud line would to the job just as well.
The three strand construction causes the rope to try and untwist under tension and that tangles up the release bridle on a Dragon Fly.
What difference does it make?
Towing Aloft - 1998/01
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!
The asshole won't put weak links on BOTH ends of the bridle so it tangles up anyway.
Maybe all of Rohan's experience with the blue rope is behind trikes?
The release on a trike is not affected by the twisting in the same way.
WHY ARE WE TALKING ABOUT USING TWISTED POLYPRO FOR TOWLINES?
I'm not a towing rocket scientist...
That's OK, Kevin. You can come into these discussions with a totally fried brain and be at no disadvantage whatsoever.
...but Bill's reasoning against the long three strand lines seemed logical and justifiable to me.
This is the first I've heard that the ninety meter towlines were twisted polypro. That doesn't let the motherfucker off the hook 'cause he shoulda shown up with ninety meter braided Spectra, however...
Maybe a better option is braided poly rope, not the three strand twisted stuff.
The best and only sane option is braided Spectra.
The stretch was nice behind the trike.
Bullshit.
Learning to manage my energy with that setup/experiment the first time was a little stressful, but not a big deal.
Oh. When you're towing with Spectra there's no energy management issue, learning, or stress involved. But the stretch behind the trike was NICE. Sure Kev, whatever you say.
(editor's note: I've car towed a bunch. As I recall now we always did have a problem with the rope twisting and we sometimes had problems with getting the three ring circus released.)
Robin's spinnaker shackle was hooked directly to the tow line. I'm thinking that in this case the weaklink twisted at the end of the tow line (woven spectra, by the way, with Bobby Bailey at the other end on a Moyes-Bailey Dragonfly), and that caused the weaklink to bind around the leg of the spinnaker release.
Ya think? It's been forty-three days since this idiot crash and ya THINK?
Paul Voight - 2005/02/21
My one bad experience with the spinnaker release and subsequent recommendation to use a ring was related to connection directly to the actual end of the tow line as in "Pro-tow" applications.
If you really gave a rat's ass about aerotowing safety you wouldn't be advising people to "Pro-tow".
I would suggest that the evidence indicates that the spinnaker release should not be directly hooked to a weaklink coming off a tow line as this has a reasonable chance of twisting the weaklink and making it hard is not impossible to release.
Pure genius, Davis.
I would also suggest that aerotow flight operation not tow pilots who have spinnaker releases hooked to the weaklinks at the end of the tow line.
What would your recommendation be about the best way to...
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.
...pry your bent pin releases open when you're high?
At the Florida flight parks and at Lookout Mountain (and other flight parks) the spinnaker shackle is tied to the keel and the weak link is not tied to the tow rope but to the V-bridle, a long piece of thin spectra...
Yeah Davis...
USHGA AEROTOWING GUIDELINES - 2004/07/30
The USHGA Towing Committee establishes these guidelines for the sole purpose of enhancing the safety of towing hang gliders aloft with a powered ultralight tow plane (Tug).
I - EQUIPMENT
B - BRIDLES
Bridle lines should be from 3/16 to 5/16 inches in diameter. Thinner lines tend to whip around more during release and can entangle the towline.
Oh yeah... an other fun fact for ya... ya know when it's far more likely to happen? During a lockout. When we're doing lockout training, the odds go from 1 in 1,000 to over 50/50.
Get those bridles nice and THIN. Do everything you possibly can to maximize the probability of killing someone and stomp out any detectable vestiges of common sense.
...whose other end is a loop hooked to a protow-type arrangement, now operating as the secondary release.
Yeah, you're probably gonna need it.
Bill pointed out in the previous issue that putting a small ring on the end of the V-bridle to connect to the spinnaker would cause a problem.
Yeah, we needed Bill to point that out to us. A five year old would never be able to see a problem like that coming.
The small ring on bridle would make it more difficult for the spectra to slide through the larger ring or carabineer at the end of the tow rope.
I repeat... Duh.
Still even in this setup it is clear there there is the potential for the weaklink to twist and for the pilot to be unable to release the V-bridle without using the secondary.
Yeah Davis. And let's not worry about what would happen...
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.
...if the bottom end were to wrap.
There is an additional problem with this secondary, it requires that the spectra line attached to the pilot's chest slide through a spectra loop to release. It is quite a bit harder for spectra to do this cleanly than it is to slide through a metal ring or carabineer (or plastic tubing).
I didn't think anybody towed with a keel attachment. We have the release on our shoulders only.
Gee, ain't it great the way the best technology spreads around the globe so smoothly.
All those ropes seem to be asking for trouble, and why not keep it as simple as possible.
And while we're at it why don't we eliminate the battens, reflex bridles, and VG systems that we didn't used to have?
Peter Birren
As Einstein said, "Things should be as simple as possible, and no simpler."
What did Einstein have to say about the advantages of a two to one "center of mass" bridle?
"All those ropes" really is quite simple. With the bridle attached to the keel, a glider can be aerotowed with far less bar pressure, and there's less need to pull in so far. This provides for a wider range of pitch control for the average flex wing.
It provides for a wider range of pitch control for ANY hang glider.
The V-bridle is very popular in the US, especially for the average weekend pilot.
It's much less popular for the average pro who's always very confident that he's never gonna need anything close to the full certified speed range of the glider.
The V-shape of the keel-pilot bridle also places an Apex release (like the Linknife) in front of the wires.
Fuck your apex release.
In case of a 45 degrees or more yaw, for example, a chest-only bridle often has the end of the towline behind the wires...
...which might present a potential wrap up problem which the V-bridle eliminates.
Which MIGHT present a POTENTIAL wrap up problem which the V-bridle eliminates. And velociraptors MIGHT present a POTENTIAL predation problem which this special repellent lotion I've got eliminates.
You're stringing all that crap all over your glider to solve imaginary problems and leaving the real and big ones wide fucking open.
We...
Your idiot inbred little cult forever stuck in early Eighties Skyting Bridle lunacy.
...also use even longer ropes for foot launched static line towing because the 7-8 meter bridle...
It really tears me up to see this poor guy struggling to near exhaustion to keep his glider under control. If only he had a clue and would use a 25 foot Hewett Bridle. And that would also make him completely lockout proof if only it weren't for adverse yaw.
To give you an idea, we occasionally show newer pilots how easy it is by launching (on smooth days) and letting go of the control bar to show the glider will track and climb with little pilot input.
- Like you can't do that on platform or one to one aero - or one point stationary winch or static when the tow angle lets you fly at trim.
- Towing a hang glider up to altitude in smooth conditions is like towing a sailboat out to the middle of the bay in a flat calm. There's not much point to it and it doesn't prove a whole helluva lot.
Letting go is of course not advised but only used as a demonstration.
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.
...when you're going up like a rocket with the bar stuffed and feel like taking your chances with some low level aerobatics. Fuckin' moron.
Pascal Legrand
I saw the animation and got the link knife.
Wish we had some video on that aerotowing stunt he pulled.
Seems interesting as a back up for the WEAK LINK...
As a BACKUP for the weak link? I got news for ya...
You're not supposed to be using the fucking weak link as a RELEASE. You're not supposed to be using the fucking weak link AT ALL. You're supposed to be keeping the goddam flight under control well enough so that you never come any closer to needing to use your fucking weak link than you are to needing to use your fucking parachute.
And you're not supposed to be going up with releases that need backups either 'cause lotsa people have died before they could even give the primary a shot.
If you think there's a one in a thousand chance that you're gonna be needing a weak link, backup release, or parachute on any given flight then stay on the ground and reevaluate the conditions, your equipment, and/or your competence.
...if it doesn't bring any other problems.
A four leafed clover in your wallet won't bring any other problems. But it's not likely to bring you any solutions either.
Peter Birren
No, it's my main release used identically for aerotowing and static line. Placed on the weaklink between towline and bridle, when it cuts the weaklink there is nothing left to do except roll up the bridle.
Yeah, twenty-five feet of it. But if you don't get it rolled up don't worry about it. At least it won't ever crush your chest when you crash like a Koch two stage always will.
It does not present any new problems of its own.
Nah, ya gotta sprinkle it with a little wheat stubble to get problems.
It's been on the market for 9 years (950 sold) and there has not been a single injury or fatality when it's been used...
Right Peter. WHEN it's been used. The problem is that like just about all the other crap out there...
I knew Rob fairly well. He was a big champion of the Linknife and one of my distributors.
- If Rob Richardson - who was a big champion of the Linknife and one of your distributors but, strangely, was using a Wallaby release - had been using your Linknife and had misrouted his bridle the same way, he'd have ended up just as dead right after Corey Burk made a good decision in the interest of his safety.
- For the purpose of the exercise you got fuckin' killed but good with that unplanned semi-loop bullshit you pulled.
- I don't give a rat's ass whether or not anybody's been injured or killed using a particular piece of equipment. You tow launch into something nasty enough you can get killed just as dead using my equipment as you can with the absolute shit that the flight parks and Davis sell - just like you can get killed launching into something nasty off a ramp hooked up to nothing and whether you're a Two or a Five.
- Is that how you base your other equipment selection decisions? Robin was killed on a Moyes Litespeed S4 and a Charly Insider. Are those off the list?
Gregg B. McNamee - 1996/12
Primary Release Criteria
To actuate the primary release the pilot does not have to give up any control of the glider. (Common sense tells us that the last thing we want to do in an emergency situation is give up control of the glider in order to terminate the tow.)
If your system requires you to take your hand off the control bar to actuate the release it is not suitable.
I know Donnell doesn't see an unplanned semi-loop performed as a byproduct of coming off tow as a problem but the crap you use is unsuitable by any sane standards.
The Linknife can also be used as a lockout prevention device...
Bullshit, Peter. You can't use your Linknife as a lockout preventer any more than Donnell can use his "center of mass" bridle or infallible weak link as a lockout preventer. You've deliberately designed a deadly autorelease device just like the one that killed Eric Aasletten.
...mostly for newer pilots.
I'm having a little trouble following this here. Lemme see if I've got this right. An experienced pilot will be less likely to survive a lockout with this device than an inexperienced pilot? Would my odds improve if I got half drunk before I hooked up to this thing?
The only good thing is releasing from the tow safely, at any attitude, with no tension or with outrageously high tension.
I got news for ya, Peter...
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.
If you define pulling whatever release you have at the cost of letting the glider popping up and over into an unplanned semi-loop as releasing from tow safely - and you do - you're a total fucking moron - and you are.
And if you define tension at or below the bottom end of the legal weak link range as "VERY" or "outrageously" high - and you do - you're a total fucking moron on that count too - and you are.
And the Linknife will do just that because line tension is applied through it, not to it. It cuts the weaklink, not the towline.
All of my stuff will handle six hundred pounds towline no sweat. And that ain't your "outrageously high" 0.8 Gs. And I don't suddenly become a helpless passenger on a roller coaster ride when I blow it.
You're a fuckin' waste of space, Peter. The benefit your Linknife has provided the sport doesn't hold a candle to the damage your stupidity and cowardice have done to it.
There is an additional problem with this secondary, it requires that the spectra line attached to the pilot's chest slide through a spectra loop to release. It is quite a bit harder for spectra to do this cleanly than it is to slide through a metal ring or carabineer (or plastic tubing). I've had this arrangement fail (on the protow when there was only a spectra loop at the end of the tow line). Luckily I had a barrel release on each end of the protowd.
I partially misunderstood this partially literate paragraph on the first take two posts ago. Not that it makes that much difference. If someone's stupid enough to forego a ring and run a bridle though a line loop the likelihood of a jam is real high regardless of whether the loop is formed in the end of a towline, in the end of primary bridle end which has just become a towline end, or by some fishing line amended to a towline end.
I was thinking Davis's one point bridle jammed in the bottom eye of the two point after a wrap but upon a reread I realize that he was protoad and did virtually the EXACT same thing Shane Smith and the rest of his Phoenix crowd did to prove Darwin right on 2011/01/15.
DOES tend to get ya choked a bit at about one and a quarter... BUT:
- in this game there's just so much stupidity that one can pile up at one time without having to pay bigtime; and
- I haven't noticed Orrin or anybody involved in that lethal clusterfuck doing a goddam thing to help me get thimbles in the bottom ends of primary aerotow bridles or even so much as advocate bent pin barrel releases on BOTH shoulders.
Lauren Tjaden - 2008/03/23 22:20:15 UTC
Eminently Qualified Quest Tandem Pilot
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.
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.
Joe Gregor - 2004/09
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.
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.
Oh yeah... an other fun fact for ya... ya know when it's far more likely to happen? During a lockout. When we're doing lockout training, the odds go from 1 in 1,000 to over 50/50.
Lauren Tjaden - 2011/07/29 15:16:29 UTC
Eminently Qualified Quest Tandem Pilot
I was flying a tandem this morning, and when I released (from the three point bridle) the line briefly released and then wrapped around the 'biner that we tow from. The sharp, strong pull almost immediately broke the weak link on the tug plane, which of course left me with the rope.
...becomes practically or totally inaccessible, welds itself shut, lassos the tow ring, or dumps the towline on the glider at Quest or whether it fails at any of the other shit operations around the globe that use it or knockoffs. If it's killed somebody at one venue it's equally capable of killing somebody else at another. I wanna hear about bench testing results and failure modes, actual and possible. And you've got none of the former and tons of the latter.
We do have a standard configuration that is different from many of the ones previously discussed on the Oz Report.
That's great! If your STANDARD configuration is DIFFERENT from many of the ones previously discussed on The Davis Show it's a no brainer that it's BETTER. It just boggles my mind that none of the other junk dealers have adopted it themselves.
Campbell Bowen and I did some testing recently.
Did Campbell and you do any load testing? Just kidding.
We tried every possible combination of possible failures that have been mentioned in the Oz Report and were not able to get our system to fail.
But I have seen others fail twice and one of them was during one of my training tandems. I just kept hitting the brake lever for a few seconds in WTF mode, and the instructor used the barrel release. The other one I saw failing was another tandem. The release just opened when they took off, around fifty feet up.
And so many others have accomplished it with no effort whatsoever. Life's just not fair sometimes.
When you were trying to duplicate the problem which caused Robin to get slammed in on tow...
At the 2008 Forbes Flatlands Greenspot for the first time was used as the standard weaklink material (thanks in large part to the efforts of Bobby Bailey). We applaud these efforts to improve the safety of aerotowing by using a better weaklink material.
The thicker the material you use the harder it is to get it to hang up. Of course the downside is that you'll no longer be using something with a huge track record and it might become possible to lock out or stall the tug.
Keep in mind that many pilots and other flight schools are using this or a very similar system in the US.
A few years ago, I started refusing to tow people with home made gear.
I like the idea of improving gear, but the lack of appreciation for the world they were stepping into didn't sit with me.
For example... flying with the new gear in mid day conditions?
Are you kidding me????
Approach it for what it is... completely untested and very experimental gear which will likely fail in new and unforseen ways as it tries it's damndest to kill you... and then we can talk.
Nothing else anybody would try to use would have as long a track record.
The wichard shackle that is used in the Bailey style brake handle and cable release is modified in several ways to align it properly...
is a properly aligned spinnaker shackle. It's DESIGNED such to operate under a longitudinal load. (Yeah, I know it's not perfectly aligned here on the model but when it's loaded up on the glider to normal tow tensions there won't be any visible misalignment.) And when it's loaded as designed, consistent with common sense, it'll dump a three hundred pound load with a nineteen pound pull on the latch.
After you off the scale stupid motherfuckers BUTCHERED it "to align it PROPERLY" that pull went to forty-eight pounds.
- They drilled it through the "W" so they could run a cable through the body and anchor it using that cable.
- That had the effect of realigning the loading to LATERAL - ninety degrees from, perpendicular to the loading for which it was designed, taking as much as possible of the loading off the pivot point and putting as much as possible on the gate and latch.
- If the assignment had been to destroy as much as possible of the mechanical advantage of this mechanism that would've been the way to do it.
- The motivation for these shitheads... The rivet at the pivot point can have a little bit of a sharp edge to it which can damage the Bobby Link. And rather than just spending a couple of minutes with a fine file to deburr it...
...also grinding the edges down slightly on the "lip" of the opening gate prevents the weaklink from hanging up after opening.
That spinnaker shackle wasn't designed or ideal for the job but it was a beautifully engineered piece of hardware before you rapists got ahold of it and defiled it with your ham handed drilling, welding, and grinding. There's NOTHING that you assholes touch that you don't turn to shit.
We twisted a weaklink on a release until it was very tight and it still released every time. We we don't see any way when using braided spectra tow lines and hooked to a V-bridle (our configuration) or protow that twisting would be possible.
Well then, I guess that Robin's release actually DID let go and the reports that it didn't are total fiction. And why bother fixing a problem that doesn't really exist?
Besides, IF anything happened it didn't happen at Quest. And your statement is that:
AT QUEST *WE* have had virtually no aerotow release issues.
Some aerotow releases, including a few models from prominent schools, have had problems releasing under high tensions. You must VERIFY through tests that a release will work for the tensions that could possibly be encountered. You better figure at least three hundred pounds to be modestly confident.
Maybe eight to ten years ago I got several comments from people saying a popular aerotow release (with a bicycle type brake lever) would fail to release at higher tensions. I called and talked to the producer sharing the people's experiences and concerns. I inquired to what tension their releases were tested but he refused to say, just aggressively stated they never had any problems with their releases, they were fine, goodbye, click. Another person tested one and found it started getting really hard to actuate in the range of only eighty to a hundred pounds as I vaguely recall. I noticed they did modify their design but I don't know if they ever really did any engineering tests on it. You should test the release yourself or have someone you trust do it. There is only one aerotow release manufacturer whose product I'd have reasonable confidence in without verifying it myself, the Wallaby release is not it.
...we've got a lot of drilling, welding, and grinding to do to fill orders. But thank you for your concern. Goodbye, click.
It is possible if there is a three ring circus or Linknife attached to a line coming off the V-bridle.
WHAT?
Additionally, the way we attach and align the wichard on our brake handle and cable type configuration, the wichard release will open with absolutely no load on the release.
Well that's just great, Awesome Bob. Now if you could only get it to open with absolutely SOME load on the release.
Bobby Bailey designed...
Don't you DARE use the word DESIGNED in the same sentence with the name of that asshole.
...this system twelve to fifteen years ago...
Well then, it's got a very long track record. What kind of numbers did you get from your load testing?
...and it has been used here at Quest with virtually no problems...
Yeah, I heard you the first time you said it's been used THERE at QUEST with VIRTUALLY no problems. And whenever I hear people repeating carefully crafted crap like that my alarm bells start ringing louder. Keep it up.
...and with a secondary release in place there is always a way to release from tow.
Lauren Tjaden - 2008/03/23 22:20:15 UTC
Eminently Qualified Quest Tandem Pilot
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.
Sure. As long as you have plenty of patience, strength, time, and altitude and a hook knife.
Glad you've perfected the ways to release from tow.
Mitch Shipley (T2C 144) crashed at launch after a weak link break. He tried to stretch out the downwind leg and then drug a tip turning it around and took out his keel (at least).
Now maybe you'll have time to perfect the engineering such that there is always a way to NOT release from tow.
We have a very descriptive guide with photos on aerotowing and the necessary equipment on our website at: http://www.questairforce.com/
under Aerotow FAQ.
Not any more you don't. You also don't have any Aerotow FAQs anymore at: http://questairhanggliding.com/
But don't worry... I've got them archived. And here's a sample:
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.
so that anybody with an IQ in the low double digits or up can see for himself what a bunch of totally incompetent douchebags you all are.
R.J. Reynolds telling everybody how healthy smoking is, Exxon Mobil warning us about the dangers of the coming ice age, and Quest Air publishing on The Davis Show...
