http://2.bp.blogspot.com/-9Ek9_lFeSII/UZ4KuB0MUSI/AAAAAAAAGyU/eWfhGo4QeqY/s1024/GOPR5278.JPGDavis Straub - 2012/11/13 06:21:01 UTC
The first five seconds of a cart based aerotow are by far the most dangerous and after that releasing with a barrel release is probably a better idea.
I'd love to read about the construction of the bridle you made for Zack!- If I had to replace my Ribbon Bridle it would be a hollow braid job spliced its entire length like the ones I made for Zack.
To engineer the junk the Industry puts people up on to be as crappy as it is you've gotta try pretty hard. And they put up - as they are all so fond of telling everyone - HUNDREDS OF THOUSANDS of tows with it. Yet still you've gotta wait a couple of decades before you got a solid unambiguous Zack Marzec out of one of the obvious sets of defects. And by the time they kill the next one everyone will have forgotten everything about the first one - other than the "fact" that he had the misfortune of flying low into a five hundred year dust devil and sometimes shit just happens.It had never occurred to me...
http://www.kitestrings.org/post985.html#p985I'd love to read about the construction of the bridle you made for Zack!
The Push/Pull Barrel Release - Necessity is the Mother of Invention
Ollie Gregory recollects the incident that spurred him to make a better barrel release...
2005/06/08. I was there when it happened.Was towing at the first east coast championship at Ridgely MD.
Mason Smawley - good guy.Think there were three tugs and a trike. The trike pilot was green.
Weren't you using a Lauren Link to keep you from getting too far out of whack?First time to tow at a comp. he was towing very fast. Almost 40 mph. The only peeps who didn't care were the rigid wings. On the first decent looking day of the meet, I hooked on his line and started towing out pretty early. Several wind techs had towed and sunk back to try again. The tows were fast, so I put very little flap on my ATOS VX. The tow was damnably smooth for a long time. We were climbing at a bout 150 fpm or les due to the trike's crummy climb rate and fast speed.
At about 1200 feet, the trike hit the boomer thermal on the fat. It was the first hint of lift on that tow. From going 40 mph with me on the string behind, the trike driver pushed out hard and climbed to the right at full throttle. I, of course, slid under and to the right of him at 40 mph even though I was doing what I could to slow down by pushing the ATOS's nose up.
See. It worked - just like it was supposed to.Anyway, all of a sudden, I was looking at loops and loops of tow line all ahead of me! The took of the prop hub release was throwing giant ATOS lassos in the sky. I grabbed my pro tow release to get off, but with no tension on the line at all, I had to let the control bar go completely to grab the line ahead of the pro tow release to keep tension to pull against for release.
Guess what happened in the next few seconds. Since the trike driver felt no load, he assumed I was off tow. Instead I was below him and to his left as I was desperately trying to get off the slack line! Of corse he did what triggers do. He turned left and dove! Suddenly all I could see was rope everywhere and the top of the tugs sail as he dove right by my nose cone! I instinctively let go if the line and grabbed the control bar with both hands just as the line came taunt and broke the weak link with the line pointing straight down!
Yeah, I guess they didn't have time to cover that in his certification process. Maybe they should extend the ground school so that they'll be able to include something on towing in thermal conditions after they finish with the five days covering the purposes of the 130 pound Greenspot standard aerotow weak link and how to tie it so that it breaks consistently at whatever anybody says it does.I could have been hit by the trike tug as it went by, or been tucked by the line yanking down hard on my bar while I had both hands off fiddling with the loose line to release. Weak link broke and I turned back to core that strong thermal which turned out to be my strongest climb of that day!
Needless to say, that evening, I gathered my tugging friends to go give the trike pilot a lesson in what to do when tugging and hitting a strong thermal.
Who signed him off on the rating and approved him for the meet?The trikenguy was a hang glider pilot originally and did what hang glider pilots do who hit a strong climb! He pushed out hard!
http://www.hanggliding.org/viewtopic.php?t=11497When I got back home, I grabbed Matt Taber...
David W. Johnson - 2009/04/11 05:46:23 UTC
I have the loop style that LMFP makes. Matt is particular about the quality of the product that goes out and you will get something reliable. I was there one time when they had a new person make a batch of them. Matt was unhappy with the quality and cut them all in half to ensure they could not be sent out. I hope that tells you about their quality.
...and set to inventing the push pull pro tow release.
Matt Taber - 2009/07/12
GT Manufacturing Inc. (GT) and Lookout Mountain Flight Park Inc. (LMFP) make no claim of serviceability of this tow equipment.
No...No one was interested in marketing it.
...shit. Including Matt:There is no product liability insurance covering this gear and we do not warrant this gear as suitable for towing anything.
- So if this contraption is - as you apparently feel - the greatest thing since sliced bread, what does that tell you about USHGA and the aerotowing industry?I gave copies to my comp pals cause I love em.
- And three hook knives - just in case.I have two on my harness.
Really?They work great.
...with the weak link being limited by the FAA to eighty percent max certified operating weight. For me - 320 pounds - that release has gotta be operational at 256 pounds direct loading - near twice that if I wanna fly something safe. How does it function in the 250 to 500 range?United States Hang Gliding and Paragliding Association, Inc. - 2006/10
Standard Operating Procedures
Part 104 - Pilot Proficiency System
11. Hang Gliding Aero Tow Ratings
02. Aero Vehicle Requirements
-F. A release must be placed at the hang glider end of the tow line within easy reach of the pilot. This release shall be operational with zero tow line force up to twice the rated breaking strength of the weak link.
and its importance relative to the necessity of dumping a slack line attached to a tug who:Gregg McNamee - 1996/12
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.
Yeah..."The Ollie" Push & Pull Barrel Release
2013/09/21 - 10:20 by Instinct
Currency: Cdn
$35.00
EVOLUTIONARY. A barrel release (aka ProTow)...
WOW!...that can be released both under tension and not under tension!
AMAZING!Steve Davy - 2013/09/28 01:19:30 UTC
I'm not understanding why slack line would've been an issue with a straight pin barrel release.
I took a straight pin release without a brake, held it vertically and found that I could actuate it with the weight of a Bic lighter attached. Then found it would actuate with nothing attached!
While you're skillfully piloting the glider through whatever emergency you happen to be in with your other hand...The retractable bungee cord helps for releasing in either direction...
Under how much tension have you tested it?...while under tension...
Awesome, dude! How wonderful it must be to go up at a Davis Meet......the bungee keeps the barrel from slipping back and causing a premature release...
http://ozreport.com/16.078Davis Straub - 2008/04/22 14:47:00 UTCPilots must use weaklinks provided by the meet organizers and in a manner approved by the meet organizers. All weaklinks will be checked and use of inappropriate weaklinks will require the pilot to go to the end of the launch line to change the weaklink.
Weaklinks will consist of a single loop of Cortland 130 lb Greenspot braided Dacron Tolling line and should be placed at one end of a shoulder bridle.
http://ozreport.com/12.080Davis Straub - 2012/04/18 15:02:09 UTC
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).
...without the risk of the inconvenience...Davis Straub - 2008/04/22 06:02:32 UTC
Casa Grande, Arizona
We were launching in light cross winds. I got on the cart but noticed that the back was too high. I ignored it and off we went. Then the glider was stuck to the cart. I finally jiggled it off the cart, but zoomed right up and blew the weaklink. Now I had to land down wind or cross wind. I tried hard as I could to get the glider to turn into the wind, but no luck (as I was only twenty feet high). So I just flared at the last second and that worked, although I was covered in dust.
I was not the only one breaking weaklinks as it seemed for a while every third pilot was having this problem. You've got to get the keel cradle set right.
What's that like? I've never been in that situation....and if you need to release while there is no tension on the tow rope...
So you don't even need to split the tension with a bridle! So if I'm flying min legal weak link I can dump 256 pounds NO PROBLEM! Cool!...the bungee can be stretched to pull the barrel away from you, allowing the release pin to flip which then allows the tow line to exit out the barrel.
That isn't a "release pin", motherfucker. It's not designed to operate as a lever. It's designed to be pulled lengthwise through a loop of bungee cord to allow a parachute container to open.Stainless steel release pins are used.
Reducing them... That's always been plenty good for me. If you were, on the other hand, talking about ELIMINATING them...Bungee connection is heat-shrink wrapped for security and to reduce snags.
...I'd just start walking away.Jim Rooney - 2011/02/06 18:35:13 UTC
I don't really have anything against the Kotch release.
I think it's big, clunky and expensive, but I'm sure it works fine.
I'm also sure it has it's problems just like any other system. The minute someone starts telling me about their "perfect"system, I start walking away.
From WHAT? Aluminum poisoning? What horrors are we hearing about from the people not using heat shrink "wrapped" barrels?Barrel is heat-shrink wrapped for your protection.
Yep... FANTASTIC idea.Credit goes to Ollie Gregory for the simple, yet revolutionary idea.
...and Dan DeWeese...Peter Birren - 2008/10/27 23:41:49 UTC
I know about this type of accident because it happened to me, breaking four ribs and my larynx... and I was aerotowing using a dolly. The shit happened so fast there was no room for thought much less action. But I wasn't dragged because the weaklink did its job and broke immediately on impact.
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.
I got news for ya, Mark... Anything stronger than the Davis mandated fishing line protecting this glider:(If you want spectra tow bridles, a pair can be added free of charge. Just email mark@instinct.pro when you place the order. They are made out of 7/64" Amsteel Spectra....it is from our used tow rope so the line is faded (that is why they are free!)...but still ample strong for aero-towing bridles.
Absolute genius.Ollie passed on the history lesson on why he came up with this design - read here:
http://instinct.pro/Necessity_is_the_Mother_of_Invention
No shit. Especially when you're going up exclusively with Flight Park Mafia options...It's prudent to have as many options to release from tow ropes as possible.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3107Jim Rooney - 2009/11/02 18:58:13 UTC
Oh it happens.
I have, all the guys I work with have.
(Our average is 1 in 1,000 tows)
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.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3391Lauren Tjaden - 2008/03/23 22:20:15 UTC
When Jim got me locked out to the right, I couldn't keep the pitch of the glider with one hand for more than a second (the pressure was a zillion pounds, more or less), but the F'ing release slid around when I tried to hit it. The barrel release wouldn't work because we had too much pressure on it.
Anyhow, the tandem can indeed perform big wingovers, as I demonstrated when I finally got separated from the tug.
Paul Tjaden - 2008/07/22 04:32:22 UTC
I have never had a lockout situation happen so quickly and dramatically and had no chance to release as I have always thought I could do.
...you already know won't work when you need them too.Matt Taber - 2009/07/12
GT Manufacturing Inc. (GT) and Lookout Mountain Flight Park Inc. (LMFP) make no claim of serviceability of this tow equipment. There is no product liability insurance covering this gear and we do not warrant this gear as suitable for towing anything.
Who's WE?We...
And make sure you have a sidewire on each wing in case one of them breaks. Idiot....recommend having a barrel release on either shoulder and of course carry a hook knife in case both barrel releases fail.
- What ARE my weak links?Replace your weak-links often...
- Bullshit....but never count on them breaking!
0:50Towing Aloft
Weak links very clearly will provide protection from excessive angles of attack, high bank turns and the like for this form of towing.
...before the glider does. So tell us about some of the incidents you know about in which the glider folded up with the fishing line still intact and ready for the next tow.Davis Straub - 2011/07/31 17:55:25 UTC
To break under load before the glider does.
Deltaman - 2013/02/08 13:57:01 UTC
Its purpose is not to protect the pilot as every ranches are saying but just to protect the glider from overload.
Fuck you, Davis. Every last one of these assholes is using and teaching the Davis Link solely as a lockout projector - including/especially you.Davis Straub - 2013/02/08 16:57:42 UTC
All the flight parks that I am aware of are quite aware of this. They tell their pilots that the point of the weak link is save the glider from overload and that they should not rely on the weaklink to save them.
APPARENTLY? There's no possible way for the people too fucking stupid to just look at it to use a test rig and tell for sure? Or are we better off just watching the debates and go with the bent pin douchebags after all the people with IQs of fifty or higher have been banned?Pin Type:
There is an ongoing debate on straight vs curved pin. Straight pins apparently take less force to release...
Oh. They MAY. Well it sounds like we should just toss a coin then. Straight pins APPARENTLY take less force to release and bent pins MAY be less prone to improper rigging....but may be prone to improper rigging.
Hey, why don't we do gliders the same way? Fuck all this certification crap. If we can't get any reliable performance test results on bent versus straight pin barrel releases and it's just a matter of debate and/or opinion how can we POSSIBLY hope to get any meaningful results on the planes themselves?We offer both for you to chose.
Go fuck yourself.If you have no preference, choose either to ensure quick delivery.
So how come the Rooney Link didn't break when it sensed that this muppet desired to get off tow and wasn't able to do so quickly enough to avoid being killed in the event of a Mike Haas, Roy Messing, Steve Elliot emergency - despite all the excellent tandem training you assholes have given him and the length of the track record of the equipment Bobby Fucking-Genius Baily perfected?Jim Rooney - 2013/03/05 01:32:20 UTC
Btw, it's nothing to do with you "counting" on the weaklink breaking... Its about me not trusting you to hit the release.
If it were only about what you want, then you could use what you like.
You want the strongest weaklink you can have.
I want you to have the weakest one practical.. I don't care how much it inconveniences you.
I don't trust you as a rule. You Trust you , but I don't and shouldn't.
http://ozreport.com/forum/viewtopic.php?t=34287Steve Seibel - 2013/10/17 18:22:15 UTC
Lockout musings/ thoughts/ questions
Enough for now about the physics of bubbles.
Why? If you develop a better understanding of any lockout related issues exactly how are you going to put it to any use? Some of us have busted our asses to develop and make available top notch technology to deal with them and you studiously ignore it, go up with absolute shit like THIS:Here is the area that I really want to develop a better understanding of:
Sorry, I was busy making sure the glider didn't get off to the side in relation to the flight path. Would you mind repeating the question?1) When the hang glider is off to one side of the towplane in relation to the flight path-- regardless of whether not the towplane is yawed and the towline is still directly in line with the towplane, or the towplane is not yawed and the hang glider pilot is looking at the side of the towplane-- does the sideways pull of the towline have any significant tendency to yaw the nose of the hang glider toward the towplane?
Never mind. I have ZERO interest in discussing anything with any of the assholes who refer to two point as three point.Specifically, in the case of a 3-point tow attachment where one of the attachment points is on the keel and significantly forward of the hang point.
I'm also not real fond of assholes who refer to negative dihedral as "anhedral".If so, this would tend to make the hang glider roll away from the towplane (due to anhedral).
Why are you asking? Are you going to make your purchase and/or design decisions based on the answer?Is this significant, or not?
- Fuck you.Are there situations where a glider with a 3-point tow attachment is more likely to lock out than a glider with a pro-tow set-up?
Yeah. CLEARLY. As in:2) Clearly, as a hang glider gets further off to the side of the towplane, his "neutral point" where he tends to hang if he exerts no force on the bar, shifts toward the corner of the control frame, toward the towplane.
It's not like a two hundred pound sideways pull on the pilot glider combo can overwhelm control authority, stand the glider on its ear, and leave the pilot pretty much centered in the control frame.Towing Aloft
Weak links very clearly will provide protection from excessive angles of attack, high bank turns and the like for this form of towing.
Yeah, we hear that observation from lockout survivors all the time. "There I was... Didn't have room to use my muscles to shift my body further over to exert a roll torque to turn back toward the towplane. Thought I was gonna die."The pilot has less room to use his muscles to shift his body further over (toward the towplane side of the "neutral point") to exert a roll torque to turn back toward the towplane.
Wanna talk about equipment that you can use to terminate a lockout prior to the popping of a Rooney Link? Just kidding.Simultaneously, are forces or torques developing that are tending to roll or turn or displace the glider further away from the towplane? If so, what exactly are the nature of those forces? Bearing in mind that the towline forces are transmitted to the hang point which is near the glider's C.G... at least with pro-tow or with 3-point tow where the top point is not forward of the hang point.
Try learning to fly on tow then.3) My own experience is one of the situations most inviting of a lockout is in a turn, when the glider is displacing rapidly toward the outside of the turn.
You were dead a millisecond after the word "exactly".Why exactly is this such an invitation to a lockout? Obviously the pilot is getting less and less room to shift his body toward the towplane. But what else is going on? As the glider starts to get further on the outside of the turn it must gain airspeed. The glider's drag on the towline will increase. Is there anything about this process that tends to force the glider further still to the outside of the turn? If so, what are the details of this? My impression is that in this situation the glider is tending to roll / bank away from the towplane. Is this true? If so, exactly what is causing this? Once the pilot is all the way in the corner of the control frame even with zero muscle force, he can no longer exert a roll torque away from the towplane, and any increase in towline deflection will pull the pilot against the control frame harder or pull the towline against the front wires, obviously making a roll torque away from the towplane. But earlier, when the pilot is still exerting a roll torque with his muscles toward the towplane as he shifts into the far corner of the bar toward the towplane, are there forces or torques acting to roll the glider away from the towplane?
Sounds like he missed out on Dr. Trisa Tilletti's tandem Cone of Safety training.4) Take a simpler case where the glider pilot is simply maintaining position displaced far to one side of the towplane as towplane and glider fly in a straight line.
Here's a thought... Stay in fuckin' position behind the fuckin' plane.This requires a slight bank away from the towplane. Does this require a constant roll input, or not? #1 above suggests that the glider will tend to roll away from the towplane in the specific case of a 3-point tow attachment. Is this actually the case? And not with a pro-tow attachment? That's something that's easy enough to explore hands-on.
Tug?5) Thinking about some sort of "water ski effect" -- if the tug is turning, and the glider is moving far outside the turn, obviously the glider will very quickly be left behind the tug unless the towline forces increase rapidly to pull the hang glider to a higher airspeed than it had when it was behind the tug. The glider will tend to climb, unless the pilot pulls in. Pulling in will exacerbate the effect described in #1-- the glider will behave as if it has more anhedral and any tendency for the forward tow point on the keel to yaw the glider toward the tug will create a stronger roll torque away from the club.
Common sense and a useful purpose in this sport.But with a pro-tow setup or a three-point setup with the top attachment point at the hang point rather than further forward, is there any intrinsic reason that the glider will tend to roll away from the tug at this point? Not as far as I can see... but may be missing something...
Yeah. Fuck all this bullshit. We don't need to worry about assholes who have no idea how to stay behind a tug. If they lock out and die they'll be doing the sport and the gene pools big favors.Thoughts?
