- We will often/usually add an "s" to a singular to make it plural (forum, forums - instead of fora).
- We won't ever add an "s" to the plural to make it more plural (fora, foras).
- DO NOT *EVER* do ANYTHING because you think that Americans would prefer it that way. You'll end up using bent pins for your releases and 130 pound Greenspot for your lockout preventers and invading Iraq and Afghanistan.
A tug of our club told me we change the systeme of release handle as we can actuate with less effort by hand or foot (but no objective data!)...
- You're landing with the line in tow (versus dropping it before landing).
- I'm guessing that the frequency with which you need to dump the towline from the tug in flight is about once every hundred years.
- Given the above... Replace the steel cable with Dyneema (or Vectran or something) and release via guillotine (French invention - look it up). That would take actuation effort entirely out of the equation - the more the tension the less the problem.
A retrofit would be a virtual no-brainer.
- Component 14 has on its back side a keyhole through which the cable - Component 12 - passes.
- The cable has a stop sleeve swaged onto its front end which prevents it from passing through the top/narrow end of the keyhole but allows it to pass through the wide circular opening in the bottom end of the keyhole.
- Through the front side of Component 14, drill a hole the diameter of the width of and in line with the top end of the keyhole on the back side.
- Enlarge that hole through the front side to the diameter of the cable hole through Component 10 - the lever (which is undoubtedly the same diameter of the bottom end of the keyhole).
- Into the bottom end of the keyhole weld (or maybe epoxy) in a steel disk of that diameter with its top sharpened to a knife edge.
From the right/starboard side it looks (roughly) like this:
./|
|-|
|-|
|_|
(Ignore the period.)
(Or maybe file a V into the top end of the disk so it cuts like a hook knife.)
- Lose Component 12 - the cable.
- Replace the steel cable with a length of Dyneema with a thimble in an eye splice in its back back end and its front end head fused.
- Feed the Dyneema in through the rear as you would the cable, keep going until the end protrudes through the front side of Component 14, tie an Overhand Knot in the end, and you're good to go.
- Assuming, of course that the knot doesn't pull through before you get to weak link capacity - you may have to experiment with different line thicknesses and/or knots.
- Make the Dyneema long enough so you can reuse it a bunch of times (a little shorter each).
- Then use a front end weak link light enough to prevent damage to Component 14. You could experiment with a short mock-up of whatever square tubing AirCreation uses for that.
- Preflight to make sure that cutting disk is staying in place.
How do you manage this to have the good L/A ratio you said ?
GET A TUBING CUTTER!!!
Are you guys still using stone tools over there? I thought all the Neanderthals came over here and started running all the flight parks, flying all the tugs, and getting elected as USHGA directors.
And then bevel out the ends of the barrel. You're using aluminum - you can do that with a good steel knife blade.
It looks like you're using the same pin and diameter tubing - your problem is undoubtedly that jagged metal cutting into your line. You can easily see where it's chewing up the sleeving.
You should be able to blow well over three times that just pulling back with two fingers.
What did you mean by 'more required control effort' when towing one point? Most pilots I've talked to who do it say they have better control.
Tad Eareckson wrote:Just "a" V bridle? Hmmph.
Ha...sorry for not gushing about the virtues of your bridle, but I wanted to stay to-the-point as much as possible. I was surprised Davis disputed the pull-in thing but realized I didn't have any hard evidence of it so wanted to dig deeper. But the pictures Jim and I posted speak for themselves.
Tad Eareckson wrote:If you open it up to surface towing I can give you a couple more.
Please do. =) I never felt pitch control was an issue surface towing single point. Unlike aerotowing, no pull-in is required on tow.
What did you mean by 'more required control effort' when towing one point?
Wills Wing
Towing without a top release will cause the base tube to be positioned much further back during tow, the glider will have increased pitch pressure...
Yeah, it was an overly broad statement colored in no small part by the post traumatic stress disorder I suffer as a consequence of my first ever aerotow the better part of twenty-five years ago.
Fast Cosmos tug, real pitch stable Comet 165, one point, foot launch.
Couldn't get kicked into the boot of my cocoon under tension and was too scared to fool around with it when Jon Leak slowed down to give me the opportunity. So I was pulled by my armpits the whole tow and was flashing pain from those areas for a couple of days afterwards (while doing a fever from some flu bug I happened to pick up at nearly the same instant).
You pretty much had to keep your arms locked to stay level with the tug and if you weakened and got a bit high for a moment it was a super bitch to get it back down. The worse it got the worse it got and I finally just lost it altogether. At the point I was looking almost straight down at the trike (not exaggerating) at nine hundred feet I figured the tow was over and pulled the pin.
What with faster, better gliding, low twist / pitch pressure modern kites and nice slow Dragonflies this is a hugely reduced issue, but still, like Wills Wing says, if you're one point on a glider that's trimming slower than the tug at any given moment you're gonna hafta use a little extra muscle to bring/hold it where it needs to be.
Most pilots I've talked to who do it say they have better control.
Yeah, you effectively weigh more so you'll get more effect per inch of control movement (but that inch will cost you more muscle as well). But...
- As we all know, people who haven't acclimated to that better control often end up all over the sky.
- If I'm gonna hafta deal with ANYTHING nasty - sight unseen - I'll take two point 'cause speed ALSO gives you a lot better control and I've got a lot more speed available with two point.
...and lockouts are much more difficult to correct.
And that also seems to be the sentiment of the manufacturer. (The statement's a bit stupid though - 'cause a lockout is, by definition, something that's IMPOSSIBLE to correct.)
Ha...sorry for not gushing about the virtues of your bridle...
PLEASE don't gush about the virtues of my anythings on either of the Axis Of Evil forums - I don't have enough moles at my disposal to take that kind of risk. Probably best to limit things to embarrassing Davis on The Jack Show and Jack on The Davis Show.
I was surprised Davis disputed the pull-in thing...
I'd have been astonished if he hadn't.
...but realized I didn't have any hard evidence of it so wanted to dig deeper.
I don't have any hard evidence that if I hop over the rail at the high point of the eastbound span of the Chesapeake Bay Bridge I'm gonna be wet in under four seconds but I can use Newtonian physics to make a pretty good prediction. The one/two point thing is just a little bit more complex.
But the pictures Jim and I posted speak for themselves.
Yeah. No offense, but ESPECIALLY the one of Jim's:
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(Wouldn't you agree with me on this, Bob?)
Please do.
I was cross-eyed by the time I got all that together and posted it. Realized later that I actually only had one for sure and meant to go back and edit but you got back in before me.
Eric Aasletten - 1990/07/05.
I always link it with Brad Anderson - 1990/03/29. That report reeks of cover-up and I strongly suspect that it was thermal catalyzed - but no proof. It's always better when one of these happens at a big event with lotsa witnesses around who say things before the leadership has a chance to get everyone on the same page with the same half-baked story.
Of course it wasn't Eric's lack of pull-in authority that got him killed but the fact that he was blown off before he had the opportunity.
And since it was platform two point wasn't an option but if he hadn't been using that idiot release configuration he'd have had the bar at his knees and been happy to buy a six-pack for anyone willing and able to get a line on his forward keel and pull down on it.
I never felt pitch control was an issue surface towing single point. Unlike aerotowing, no pull-in is required on tow.
Mike Nooy takes off to our left, and he launches right into a dust devil. Like I said, they've been coming in every ten minutes or so, and you can't see them as the paddock is pretty green.
As long as you have ribbons and watch them before committing. That was static but it could've been pretty ugly with platform too. Hell, it could've been pretty ugly still high on final.
---
2022/03/29 00:15:00 UTC
Tad,
I will take time to study your proposed modification of our tug release and will come back for this.
BARREL RELEASE
Now, I think I missed something to have the right L/A barrel release even after change my prehistoric tools..
At 50kg, it seems to me too strong. My aluminium tube is not the same as yours. not only the 6021 but the ID I think. Mine is 6mm ID , yours is 0.259" ID = 6.6mm.. and you can use a 3mm leechlin as I can't . 2 strands of 3mm with the pin are too thick. I'm surprised that 0,6mm is enough to make such a difference. So I use a 2mm leechline (dyneema breaking at 211kg) and tested the barrel with the same 2mm as the wl or bridlelink loop.
When I try with the thinner greenspot, it s clearly better. Maybe a 3mm leechline with a 2mm wl will offer a better result, but I need an another barrel..
THIMBLE at the BOTTOM END of a PRIMARY BRIDDLE
you choose a 3mm ID thimble (for a 4x 2mm = 8mm overlap?) how do you attach it to the loop of the bridle? (which knot and good stitches ?) Which diameter of dyneema leechline?
TUG's POINT OF VIEW
What do you answer to a tug pilot whom you explain that you would prefer a heavier wl and who tell you that he is scared when a hangglider climb too hard at the take off and avoid the tug to do it too and menace it to finish on the culture at the end of the run.. So he explained you that he would prefer as his point of view a wl which can blow at this moment to save him and his machin..
I received the STEEVRELEASE and got a mail:
Hi Antoine
[...]
I personally test each release at my full body weight (230lbs) before shipping to make sure they can be easily operated it is however important to anchor the release handle as they operate by a short Sharpe jab.340lbs seems to be a little excessive for aerotow weak link? However it should be no problem .We have a group here that have taken to using them for winch tow (higher pressure) and are praising the ability of the release.
Looking forward to your review
Steve
- Forwarded Message -
From: Sam Kellner
To: catstevan@yahoo.ca
Sent: Sun, May 22, 2011 2:23:22 PM
Subject: stevrelease
Steve, SkyDog,
Sam Kellner down in SW Texas. About the release I purchased several months back.. We are VERY satisfied with your product.
Actually, it was for Terry Mason, ushpa #31982, SWTHG club VP. Originally an Okie, the harsh winters drove him South, to Tx, '08, don't laugh too loud. Being physically challenged from childhood polio slows him very little.
At 140lb hook-in, he is often the light man out, and most effected by breezy conditions. He's flying a 145sq, older double surface, and always in control.
Several weeks ago we were flying PL, at Hearne, Tx., on such a breezy day, but it was streight down the runway. I was at the winch.
At about 100ft agl, Terry got off to the left a bit and went into a lockout. The winch was still paying out, so there was considerable pressure on the line.
Just at the last split second, he pulled the Steevrelease. Right there on the basebar. Two fingers in the loop.
It was all really coordinated, turning the lockout into a 360* and leveling out in plenty of time to roll in on 6" wheels.
I'd say Terry saved his own ass, but your SteevRelease saved my ass because it happened so fast, I was probably not ready to cut the line or dump the pressure.
Thanks for all You guys do for the sport. Thanks for all the thought that went in to the release.
I will test it soon, and I can tell you now that the window of the release is quite too small to use the bridle loop confortably, and that a wl should be change every release.
I will take time to study your proposed modification of our tug release...
When I last wrote I was thinking that the schematic was showing just the right/starboard end of Component 14... I thought it was a frame component which continued on around to the left/port.
Now I think that it's showing it as it actually is - just a little trapezoidal piece of square tubing maybe four inches long whose sole purpose is to house the release workings.
If that's the case and it is (or could be) steel I would just make a duplicate EXCEPT...
Instead of the whole keyhole DON'T drill out the bottom circular area but just have a sharpened edge at the top of where the circular area would be.
My aluminium tube is not the same as yours. not only the 6021...
That shouldn't matter. Harder is better but I originally used polyethylene tubing and it worked very easily with very high loads. I doubt there'd be an appreciable difference between 6021 and stainless steel.
...but the ID I think.
I can't believe that's an issue either. My earlier versions had a triple overlap of eighth inch Dacron leechline (although not with the pin overlapping as well) and the added resistance was negligible.
If you're not having a problem closing the release when it's untensioned the thickness of the components inside isn't the issue. (As a matter of fact the line will get a little thinner when it's loaded.) And you've got so much extra room on the top end that I'm having a real hard time imagining that the pin shaft could be thick enough to cause a problem at the bottom.
You've beveled (smoothed, rounded) the inside edges of the tubing ends, right?
When I try with the thinner greenspot, it's clearly better.
That WILL make a bit of a difference.
But I think you're closing the barrel release too firmly. I think your problem is just getting it started.
Your 4 millimeter Vectran Primary Bridle material will fit it fine. Just make the eye slice small enough that the Thimble pops in snugly. Under loading the eye will enlarge a good bit but also under loading the Thimble will be trapped and won't go anywhere. Only if the eye splice is large enough to allow the Thimble to fall out when things are slack could you have a (potentially dangerous) problem.
What do you answer to a tug pilot...
Before or after I broke a spare downtube over his head?
1. I don't know if you've got any interesting relevant data but it's virtually impossible to find incidents of tugs being compromised by hang gliders. Lots of dead locked out or stalled hang gliders but the tugs aren't having problems.
Do you see the:
- trike having a problem?
- 130 pound Greenspot helping it to have less of a problem?
- trike making any effort to release?
2. When tugs DO have problems it's because they haven't flown properly and/or are using crap releases that don't work under load.
3. One of the most dangerous threats to either or both planes is a slack towline. Despite what you may have heard from the US, a weak link is of very little use in preventing the towline from slackening (and wrapping around a wingtip).
Ralph Sickinger - 2000/08/26 22:18:20 UTC
After towing to altitude, Sunny waved me off; I pulled on the release (hard), but nothing happened! After the second failed attempt to release, I thought about releasing from the secondary, but before I could move my hand the tug stalled and started to fall; Sunny had no choice but to gun the engine in attempt to regain flying speed, but this resulted in a sudden and severe pull on the harness and glider; I was only able to pull on the release again, while simultaneously praying for the weak link to break. The release finally opened, and I was free of the tug.
4. A loop of 130 pound Greenspot cannot prevent a tug from stalling. If you can stall a tug with a loop 130 pound Greenspot you can kill a tug with a loop of 130 pound Greenspot.
Dick Reynolds - 1992/11
Rising Fawn, Georgia
Four months have passed since my crash. Fortunately, I've regained control of the old brain, and would like to take this opportunity to pass on my experience in hopes that the rest of you might avoid a similar predicament.
Lookout Mountain Flight Park had acquired a new Moyes aerotug and I was the pilot - claiming 200 plus tows to date. At 11:00 AM on May 17, 1992 I had decided to take two more tows and then call it quits for the day.
The conditions on this particular morning were very light - great for towing. Takeoff went smoothly, with the glider then the tug lifting off, thus increasing my angle of climb. My airspeed was four mph above stall. I took my eyes off the indicator to watch the hang glider's progress when the engine abruptly seized. I can distinctly remember taking my hand off the throttle to wave the hang glider off, and it was at that point that I fully realized there was no time! I pulled the release and pushed the stick forward.
All this occurred somewhere around fifty feet. The combination of high nose angle plus the pull exerted by the climbing hang glider brought me to a screeching halt, so to speak. I believe my response time was less than a second, but this still me just hanging with very little elevator authority. The nose fell through the horizon to 30 degrees negative and the ground rapidly rushed toward me. I attempted to pull up at approximately 25 to 30 feet, with no response. My feet, butt, and gear impacted simultaneously.
I consider myself fortunate in that my friends were there to immobilize me. The doctors tell me that I'll be walking in a year or so, but that I shouldn't plan on winning any foot races.
I've spent a lot of time (sometimes it seems like that's all I've got!) talking with many knowledgeable individuals about this accident. I believe that tow pilot survivability can be improved as he/she passes through the "low and slow" envelope. From takeoff to a minimum safe altitude of approximately 150 feet, the tug will have to fly five or six mph faster. This will, of course, make it more difficult for the hang glider pilot, but will allow the tug more airspeed margin.
After 150 feet the tug may then be slowed to accommodate the glider. Until then the tug pilot should ready to release at the slightest indication of trouble. Doing so can yield that "fraction of a second" that will give the tug the edge. The glider will have ample speed and after releasing from his end should enjoy a safe landing.
See?
The United States Hang Gliding and Paragliding Association, Inc.
Standard Operating Procedure
12. Rating System
02. Pilot Proficiency System
10. Hang Gliding Aerotow Ratings
-B. Aero Vehicle Requirements
05. A weak link must be placed at both ends of the tow line. The weak link at the glider end must have a breaking strength that will break before the towline tension exceeds twice the weight of the hang glider pilot and glider combination. The weak link at the tow plane end of the towline should break with a towline tension approximately 100 pounds greater than the glider end.
5. In the US you're SUPPOSED to be able to tow with a two G weak link and the goddam tug is SUPPOSED to stay a hundred pounds over you. That's consistent with what the FAA specifies is safe for sailplanes.
6. Anybody who flies with a weak link - or a parachute - because he thinks he's going to need it shouldn't be flying.
...and menace it to finish on the culture at the end of the run.. So he explained you that he would prefer as his point of view a wl which can blow at this moment to save him and his machin..
If he's using a weak link one, one and a half, two times your flying weight it WILL (assuming the structure on the tug is adequately engineered) blow before the back end is torn off. That doesn't mean he won't crash and die afterwards - or before.
Say he has a 120 kg weak link on his end and is landing into a smooth fifteen mile per hour headwind and the tow ring catches on the end of a long flexible branch on a treetop. There may not be enough of a shock to reach the breaking tension before the tug is pulled out of control beyond a point of recovery.
If he's planning on snagging stuff during landing approaches he'd do a lot better keeping a finger on the trigger whenever he's within striking distance.
I personally test each release at my full body weight (230lbs) before shipping to make sure they can be easily operated...
That's good to hear but I'd like to know how "easily operated" is being defined.
340lbs seems to be a little excessive for aerotow weak link?
For me that's 1.06 Gs and the US regulations allow me nearly twice that. So no.
(higher pressure)
I see that pressure and tension are the same thing in Canada too.
The winch was still paying out, so there was considerable pressure on the line.
Let's not use the terms "pressure" and "tension" interchangeably. Drives me nuts.
1. I keep trying.
2. And if the line hadn't been paying out the TENSION could have been less, the same, or more.
Just at the last split second, he pulled the Steevrelease. Right there on the basebar. Two fingers in the loop.
It was all really coordinated, turning the lockout into a 360* and leveling out in plenty of time to roll in on 6" wheels.
All that stuff I like but...
Sam Kellner - 2011/05/05 04:25:07 UTC
It was a super tow to cloud base ~2500'. As the tow vehicle neared the end of the runway, I glanced down to visually locate the release pin line.
Maybe two seconds later, I felt a normal thump of release and the tow line fell away.
Does that mean that if Sam had been in the same situation trying to find his three-string release lanyard he'd have been dead?
I'd say Terry saved his own ass, but your SteevRelease saved my ass because it happened so fast, I was probably not ready to cut the line or dump the pressure.
Nobody ever is. That shouldn't even be THOUGHT of as useful emergency procedure.
That system incorporates a Ribbon Bridle as the primary / two point bridle.
A Ribbon Bridle has loops / eyes (U shaped) stitched onto the ends.
The top loop is secured with the number of stitches it takes to hold about one and a half Gs of towline tension.
The bottom loop is secured with an additional several stitches to ensure the bottom end is about twenty percent over the top. Thus the bottom will definitely or almost certainly blow if the top blows or is released respectively.
The Ribbon Bridle was a real labor intensive, tedious, time consuming bitch to produce and I've rethunk a few things recently.
I'm now using a more conventional spliced hollow braid Primary Bridle.
The Primary Weak Link is a loop of 250 pound line which I tested to blow at 274 pounds and am recommending as a one-size-fits-all. It limits towline tension to (about) 477 pounds.
There is no weak link on the bottom end of the Primary Bridle - just a Thimble.
The weak link (Bridle Link) between the shoulder mounted releases blows at 360 pounds and is only intended to be used as a secondary weak link for two point towing. For one point you'd use one that blows at 468.
Zack has a photo of the two point configuration up at:
'cept he's using twin Barrels instead of a Barrel and a Four-String. (And his primary release (which you can't see anyway) is one of the new Lookout jobs.)
Do you see the:
- trike having a problem?
- 130 pound Greenspot helping it to have less of a problem?
- trike making any effort to release?
a) Here the microlight had time to climb cause the hangglider start to roll rather than continue to rise. That's not exactly the case I would to talk
b) I'm sure it won't be better without a wl, I can imagine worse.
Ralph Sickinger - 2000/08/26 22:18:20 UTC
...but before I could move my hand the tug stalled and started to fall; Sunny had no choice but to gun the engine in attempt to regain flying speed, but this resulted in a sudden and severe pull on the harness and glider; I was only able to pull on the release again, while simultaneously praying for the weak link to break. The release finally opened, and I was free of the tug.
4. A loop of 130 pound Greenspot cannot prevent a tug from stalling. If you can stall a tug with a loop 130 pound Greenspot you can kill a tug with a loop of 130 pound Greenspot.
Ralph don't say exactly why the tug stall !? I didn't read it is cause of the hangglider.. maybe just after a thermal with a too low speed..
But for sure if I were a physician, I would have a look on the force needed to rotate the tug by climbing too much. As the force is on the back of the microlight (behind the CG) I can imagine it's vulnerable maybe depending on its power..
Oh good. Someone besides me is posting. And I had only slashed one wrist - and not very deeply.
Barrel release...
Sorry, I meant to say something about the LENGTH of your barrel. I make mine four inches, a bit over the width of the palm of the hand. It's a lot easier to pull something on which you can get a full grip.
Also, I apply glued-on length of heat shrink tubing over the aluminum barrel. (It's a somewhat tedious process described in Mousetraps.) That increases the effective diameter and makes for a better grip.
Not really a safety issue but there should be enough material inside the barrel to offer a little resistance before the assembly is feeling tow tension - otherwise the release is prone to falling open during preparation for launch.
Weak links...
Single loops of 130 pound Greenspot on solo glider bridle ends both blow in smooth air when everything is lined up and going fine and hold well into horrendous lockouts which, if and when low enough, can and do crash and kill people.
Here the microlight had time to climb...
Yes, but this first timer does about the worst thing he can to a tug - climbs out fast and very high immediately upon leaving the cart - and the tug does just fine anyway and, while having plenty of time and opportunity, apparently makes no effort to release. If the camera were only on the tug you wouldn't have been able to tell that it wasn't a normal tow - that there was a glider back there trying to kill himself and coming within a foot or so of success.
Ralph don't say exactly why the tug stall !?
Good point. I've been using that example for years without really thinking about it and it's not all that good.
Undoubtedly Sunny stalled the Dragonfly by slowing it down to relieve as much tension as possible to help Ralph out with his notoriously problematic release.
However...
That weak link is capable of holding to 260 pounds of towline tension when it's on the end of a one point bridle. In the US the minimum power requirement for a tug is 250 pounds of thrust. That's 250 pounds to keep BOTH planes in the air and ONE of them can deliver 260 pounds of reverse thrust. Do the math.
But for sure if I were a physician...
ANY pull on the towline compromises the performance and safety margin of the tug. The tug is ALWAYS better off without the glider. Thus there is NEVER a downside for the tug having a really light weak link. No tug has ever been crashed or killed because a weak link blew. (Physicist, by the way. A physician is a medical doctor.)
But that's definitely not the case for the glider.
The tug exists for one purpose: to get gliders off the ground and to altitude as safely - for all concerned - as possible.
If the tug is concerned only about optimizing his own safety he should mandate that the glider uses a weak link so light that the glider doesn't even make it off the ground. This is what Rooney and most US and Australian tug drivers do. The problem is that occasionally gliders make it into the air anyway and putting a glider up on a weak link on the ragged edge of failure is about the most dangerous thing you can do to it - without using a pair of wrenches or hack saw. Virtually ALL aerotow crashes occur as a sole or primary consequence of weak link failure.
Or if he wants to be REALLY safe he shouldn't tow gliders at all and just fly as an ultralight. But even then if he's flying in thermal conditions he can find himself in situations which dangerously compromise his control.
And, now that I think of it...
I only know of one Dragonfly driver who's been hurt while towing who'd have been better off without the glider. And that glider was UNDOUBTEDLY using 130 pound Greenspot. He had the engine seize at fifty feet. And the driver did a bunch of things wrong. He was too slow to begin with, started waiting for the glider to respond to a release signal instead of looking out for Number One and blowing him off immediately, and tried to pull out of the stalled dive prematurely.
I know of several of Dragonflies that have been killed while NOT towing - including one of the two founders of Highland Aerosports (Ridgely).
There was a very high profile tug fatality in the US twenty-six years ago in which a young hotshot glider jockey was driving a tug in smooth air, made a very abrupt and totally unnecessary turn which got things badly out of whack - but not locked out, and was unable to get his anemic piece 'o crap release to function before getting tumbled, broken, and ejected. (They had a parachute but left it in the trailer.)
The designated weak link was about five hundred pounds - which is about six percent over what I have on my end. But the bridle/release assembly was junk and that's what failed first at about 130 pound Greenspot max towline tension.
It's not HIGH tension that tends to get planes - virtually always gliders - killed. It's MISALIGNED tension - and you can't defend against misaligned tension with a weak link because a hundred and fifty pounds of it can kill you just as dead as five hundred. That's why we need to have releases that work the instant we need them to with - strange as it may seem - BOTH hands on the basetube.
But of course the total morons who control hang gliding have spent the last thirty years telling everybody that it's impossible to design a release that will work when we need it to while maintaining or maximizing glider control so we all need to use half G weak links to keep us safe.
We need to equip, fly, and think as if we didn't have weak links - because if we get into situations in which the weak link becomes "necessary" we've almost certainly already screwed the pooch bigtime and shouldn't have great expectations of surviving much beyond that point.
Just like a parachute. If you think you're going to NEED it on any given flight you're certifiably insane if you make that flight. You don't (I hope) think "I can go up...
- with this frayed sidewire...
- into these conditions...
- and perform this aerobatic maneuver
...because I have A REALLY GOOD PARACHUTE (and helmet and medical insurance plan)."
I'm sure it won't be better without a wl, I can imagine worse.
But just let me make myself very clear on this...
Flying WITHOUT a weak link is insane, stupid, and, in this country, illegal and I would never DREAM of doing it - even though the likelihood of me, or any properly equipped glider, ever NEEDING one is close to zero. They cost and weigh virtually nothing and guarantee that your releases will never be overloaded and your glider and tug will never be broken up on tow. Just don't ever expect any more than that out of them because that's ALL they're supposed and can be relied on to do.
So just use weak links about one and a half Gs or a little over, forget about them, and go flying.
P.S. Thank for helping to put our first Kites thread into four digits worth of hits.
P.P.S. Oops.
Can no longer access Flickr on my old/main computer and just logged on using the new machine. Had previously seen your barrel release photo only on the cell phone and now realize that you DID apply the heat shrink over the barrel.
But just let me add/reiterate...
If the heat shrink isn't glued on it tends to slip back off with a bit of use over time - even if you overlap the front or both ends. This isn't really a critical safety issue but it does get rather annoying.
Thank you again for you availability and our exchange..
What is your final OD : 10mm maybe. I will use a thick walled (+2.4mm) heat shrink 3:1 rather than the glue operation.. easier.
Vectran seems to me a good idea as it slide better than the leechline in wrapped dyneema and is thick enough to stabilize the barrel with no load.
If we could expect even better skill (L/A), why not to use a thinner tube ID 5mm ?
Something bothers me with the (short) bridlelink. I'm not sure to be confortable with barrel shifted forward (required by the length of the bridlelink) rather than on a chest on the same level of my hands on the basebar when I have to pull during AT. The way to release (and the time) to catch barrel in front seems to me longer and in bad configuration with highload and pull position, not the best I would expect..
