I guess just about all of our Bailey/Quest standard aerotow weak link breaks are gonna occur:
- shortly after takeoff
- with:
-- nothing noticeable going on with the air
-- the glider level and in perfect position behind the tug
That certainly syncs with most of my experiences and observations and, based on the scenario you're using for your little tutorials...
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).
...and your experiences, I'd guess you're coming from around the same place.
So aside from dumping us into stalls right after takeoff and forcing quick emergency landings in whatever air it is we're dealing with at the moment...
My issue with weak-links is that they typically fail at the worst possible moment. I don't tow with a lot of pressure down low, but on tow you are anchored to a system with some inertia (not the same as free flying). It is not that hard to be pitched up relatively steeply by a sharp gust.
Even with a hydraulic winch, the mass of the drum, and the drag of the line lead to a delay in the sytem's relieving of the added tow pressure. This short burst of increased tow pressure doesn't present a danger unless the damned weak-link breaks (which it is very likely to as it has no "delay" to match the lag in the system) and you are low to the ground.
How many times have you had the pads lock-up on your pay-out winch? How often have you seen the line catch on some part of the winch -WHILE IT WAS UNDER TOW. I have towed hangliders a lot more than paragliders, but I have had two low level weaklink breaks on paragliders, and TEN on hangliders, about half of which very pretty exciting (just getting upright in time in the hang glider required fast reflexes). These always happened right as I got wacked by some gust/ thermal, and the sudden, unexpected release of tow pressure didn't make the situation easier to deal with, quite the contrary.
As I stated earlier, in my entire flying career (towing for about 15 years) I have NEVER SEEN A WEAKLINK SAVE ANYONE FROM ANYTHING! I have seen a number of crashes, and the weaklink didn't break till they hit the ground (by which point the tow pressure was off already).
In that same period I PERSONALLY have been endangered a dozen times by sudden, unexpected, total release of tow pressure right as I am being pitched up by a gust/thermal. If you can control your wing, the line is your friend. If it is so bad you can't, release! If you can't release, there is some small chance that the weak link MAY release for you (but not in a "normal" lock-out), but I personally would much rather rely on the winch operator in such a rare occurrence, than the random release of the line provided by a weak link.
For a weak-link to provide the critical measure of safety, you have to have:
- 1) the kind of mechanical failure described, combined with
- 2) poor/ inadequate response from the winch operator, AND
- 3) somehow be unable to release yourself. HAS THIS EVER HAPPENNED IN THE ENTIRE HISTORY OF TOWING PARAGLIDERS? Would using a release system that included a secondary means of release make such an occurence almost impossible?
I have twice had a "mechanical" failure of the pressure system. Once, static towing a PG with my dad, he simply floored it when " the pressure needle kept bouncing around so I ignored it", and again- static towing- when the line hooked uder a runway light, and the pressure suddenly shot up. I RELEASED.
I had an incompetent tow operator + no observer the first time (STUPID), and my weaklink DIDN'T release as I locked out as I let go of the brakes to reach for the release on my "standard" style "v" bridle (the weak-link was probably a lttle too strong, but with a static line, it simply snapped every time as you pulled up the glider otherwise). The second time, the tow car was just reacting to the problem as I released (but static towing paragliders sucks no matter what).
Again, I'm not talking theory, I'm asking other pilots to recount how often they've been dumped off, low, in a "tight spot" by a weak-link break, vs. the number of times they've PERSONALLY WITNESSED, or have experienced being "SAVED" by a weak-link break. I figure it has to have happenned somewhere, somewhen, but does it remotely compare to the DAILY OCCURRENCE (if you are launching in thermals), of unneccessary, unneeded weak-link breaks that actually add to the danger if they happen close to the ground?
If you are using a decent tow system (not static line) with a competent operator isn't it possible that it is safer to tow without a weak-link? This has certainly been my personal experience and observation. What about other pilots?
...what's the purpose of this weak link?
Tost says...
Tost Flugzeuggerätebau
Weak links protect your aircraft against overloading.
...it's to protect your aircraft against overloading. But it doesn't sound like your glider is in much danger of being overloaded.
For whomever asked about the function of a weak link, it is to release the glider and plane from each other when the tow forces become greater than desirable -- whether that is due to a lockout or a malfunction of equipment or whatever. This can save a glider, a tow pilot, or more often, a hang glider pilot who does not get off of tow when he or she gets too far out of whack.
...it's to save a hang glider pilot who doesn't get off of tow when he or she gets too far out of whack. But it sounds to me like he or she is perfectly in whack and would prefer to climbing out to being dumped into an immediate stall.
Enjoy your posts, as always, and find your comments solid, based on hundreds of hours / tows of experience and backed up by a keen intellect/knowledge of the issues when it comes to most things in general and hang gliding AT/Towing in particular. Wanted to go on record in case anyone reading wanted to know one persons comments they should give weight to.
The "purpose" of a weaklink is to increase the safety of the towing operation. PERIOD.
...it's to increase the safety of the towing operation - PERIOD. But it seems to me like dumping in whack gliders into stalls on takeoff does the precise opposite - PERIOD.
You know, after all this discussion I'm now convinced that it is a very good idea to treat the weaklink as a release, that that is exactly what we do when we have a weaklink on one side of a pro tow bridle. That that is exactly what has happened to me in a number of situations and that the whole business about a weaklink only for the glider not breaking isn't really the case nor a good idea for hang gliding.
I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
...it's a good emergency release. But seeing as how emergencies in which you'd wanna be OFF tow very seldom involve much in the way of tension until after it's too late...
Tost is the only one who's making much sense to me and - if they're right on there issue - shouldn't we be towing our six G gliders with something that doesn't vaporize when the glider's climbing out normally in perfect whack?
Hang Gliding and Paragliding Fatalities Jan 2013 Through July 2013
(This report covers fatalities occurring in the USA, involving USHPA Members Only)
Hang Gliding Fatalities
2-8-2013 - Zack Marzec
Zack Marzec (27), an H-4 Pilot with Aero Tow and Tandem Aero Tow proficiency as well as Advanced Instructor and Tandem Instructor appointments, and a USHPA member since 2009, suffered fatal injuries when when his glider tumbled during an aero tow launch. During the launch, at an altitude of 150 AGL, the pilot encountered an invisible bullet thermal which pitched the nose up, causing the weak link to break. Upon the breakage of the weak link, the glider whip stalled and then tumbled twice. The pilot and glider's leading edge hit the ground simultaneously. The pilot was utilizing his own pro-tow style tow harness, this own high performance glider with VG on, and was not wearing a full face helmet.
2007 Hang Gliding Accident Summary by Joe Gregor and Bacil Dickert (PDF)
2005 Hang Gliding Accident Summary by Joe Gregor (PDF)
2004 Hang Gliding Accident Summary by Joe Gregor and Brian Vant-Hull (PDF)
2003 Hang Gliding Accident Summary by Tom Johns (PDF)
Hang Gliding Accidents - The First 20 Years by Doug Hildreth (PDF)
For the past five and half years I've been figuring that a report on a hang gliding "accident" is just BOUND to appear - any day now! But when you're dealing with an organization as effective addressing hang gliding safety as USHGA is you've just gotta be real patient most of the time.
2-8
Oh good. You got two whole characters down before a major fuckup. He was killed on the SECOND. Or did you do that deliberately to make it appear that you gutted the USHGA Aerotowing SOPs of all references to equipment the day BEFORE the crash - instead of five days AFTER?
-2013 - Zack Marzec
Zack Marzec (27), an H-4 Pilot with Aero Tow and Tandem Aero Tow proficiency as well as Advanced Instructor and Tandem Instructor appointments...
From whom did he obtain the ratings and appointments and what are their comments on this fatality?
...and a USHPA member since 2009, suffered fatal injuries...
What kind of fatal injuries?
...when when...
Got a stuttering problem? When I run this through Microsoft Word's spellchecker it catches it.
...his glider tumbled during an aero tow launch.
BULLSHIT. It tumbled AFTER the focal point of his safe towing system ABORTED the aerotow launch. The worst thing that happened to him DURING the aerotow launch was a steep climb - and most people survive steep climbs just fine. Just ask anybody on the International Space Station.
During the launch, at an altitude of 150 AGL...
- 150 *WHAT* AGL?
- How 'bout canning the "AGL" crap? We bloody well know it's AGL. When somebody falls off a ladder it can be safely assumed that it probably wasn't twelve feet MSL.
- The estimate was 100 to 150 - FEET.
...the pilot encountered an invisible bullet thermal...
- It was an INVISIBLE bullet thermal? So it probably consisted mostly of air - which tends to be invisible in Florida at that time of year. So he probably had no fuckin' clue what he was about to fly into.
- What about the tug that had just been blasted up by the invisible bullet thermal about five seconds prior? Was it invisible too?
- How 'bout the towline? Was it also too invisible for Zack to have been able to track the invisible tug position?
- How did he know where to fly? Was he homing in on the engine noise?
- Bullet thermal my ass. It was:
-- a SUSTAINED MONSTER that Mark doesn't report flying out of before Zack flew into it
-- probably the size of a goddam football field and Mark reports that it was still cooking when he came back down and he altered his landing to avoid it
- At what point did you lying motherfuckers figure out that an invisible bullet thermal made a better story than an invisible dust devil - as it conflicted slightly less with Mark's original documented statements?
...which pitched the nose up...
Where was the bridle trim point on the keel? Do you think it was far enough forward?
...causing the weak link to break.
- Causing WHAT weak link to break?
-- What material was he using and how well was the knot hidden?
-- How many Gs?
-- Where did it fall with respect to the legal range?
-- What glider was Zack flying and what was its max certified operating weight?
- What's the purpose of this "weak link"? I've heard from one of Zack's bereaved friends that it's to increase the safety of the towing operation - PERIOD. If that's indeed its purpose it doesn't seem to have worked very well.
- Was it necessary for it to break? Was it protecting Zack from getting too far out of whack? If Zack was getting too far out of whack how come:
-- he didn't release?
-- his driver didn't release him?
Upon the breakage of the weak link, the glider whip stalled...
So the glider was doing OK before the breakage of the weak link? It wasn't until after it broke that the glider whipstalled?
You're the one advocating change here, not me.
I'm fine.
These are only questions if you're advocating change. Which I'm not. You are.
You're the one speculating on Zack's death... not me.
Hell, you've even already come to your conclusions... you've made up your mind and you "know" what happened and what to do about.
It's disgusting and you need to stop.
You weren't there. You don't know.
All you have is the tug pilot report, who himself says he doesn't know... and HE WAS THERE... and he doesn't know.
Ever heard of "Confirmation Bias"?
Because you're a textbook example.
You were out looking for data to support your preconceived conclusion, rather than looking at the data and seeing what it tells you... which is why this is the first time we've heard from you and your gang.
Go back to Tad's hole in the ground.
While you're there, ask him why he was banned from every east coast flying site.
...nobody really had a good idea what the problem was. You're not just SPECULATING, are you?
...and then tumbled twice.
So he was going up, the weak link broke, and then he whipstalled and tumbled twice. Good thing he was using a 130 pound Greenspot Quest Link, wasn't it? If he'd been using a Tad-O-Link he'd have whipstalled even worse and probably tumbled three or four times.
The pilot and glider's leading edge hit the ground simultaneously.
Eye witnesses said the glider tumbled twice and then struck the ground with the base tube low.
five days after the fact.
- How come you're reporting what part of Zack's glider hit but not what part of Zack hit? Seeing as how the glider survived in pretty good shape and Zack didn't at all wouldn't it be more important to know what part of Zack hit?
The pilot was utilizing his own pro-tow style tow harness...
- Oh. HIS OWN pro-tow style tow HARNESS. That homemade crap that Rooney's always warning us about. Shoulda been using a pro-tow style harness he purchased from Quest. Lot easier to hold the nose down with a professionally produced pro-tow style harness.
- What's a "pro-tow style tow harness"? I searched the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden, cover to cover and couldn't find any information on the pro-tow style tow harness.
- What would happen if an amateur tried to fly one of these pro-tow style tow harnesses? Could he be injured or killed as a consequence of lacking the necessary experience and skill to safely handle it?
...this...
Pronounced: "his". (The "t" is silent.)
...own high performance glider...
Too much trouble to tell us what it is and what the manufacturer recommends for the bridle and weak link?
...with VG on...
How much VG? Quarter? Half? Three quarters? Full?
- Wills Wing recommends half VG for aerotowing their gliders.
- How come neither Mark nor Paul make any mention of VG in their reports?
- Was he wearing sunscreen? Are you sure he didn't die of skin cancer?
- Got it. If he'd been utilizing a:
-- Quest pro-tow style tow harness
-- borrowed low performance glider with the VG off
-- full face helmet
he'd have been fine.
That's what you're saying, right? Hell, even if he'd just been wearing a full face helmet the fatal injuries he sustained would almost certainly have been prevented. (Bit odd though that at no point in the hours, days, weeks, months following the crash did Mark Frutiger, Paul or Lauren Tjaden, Mitch Shipley, Russell Brown, Davis Straub, Jim Rooney, Bruce Weaver mention anything about the horrible injuries that Zack suffered as a consequence of his inadequate helmet and hop on the full face bandwagon, don't ya think?)
So now that you've concluded this exhaustive six month investigation you're gonna:
- put out an advisory on your home page and bump the request for dirt on Dell Schanze down to the Number 4 slot
- publish an extensive article in the magazine alerting people to the hazards of:
-- invisible bullet thermals
-- homemade pro-tow style tow harnesses
-- high performance gliders
-- launching with the VG on
-- open face helmets
But, of course, you're not actually saying these were actual issues in the fatality. You're just insinuating that they were possible factors in your usual pathetic and transparent effort to divert everyone's attention away from the two REAL issues:
- pro toad bridle
- Rooney Link
The overriding principle here is - as it's ALWAYS been...
If lotsa people have been doing something someway it's perfectly OK.
So what the hell's the point in publishing this if you have no recommendation whatsoever - two point bridle / somewhat heavier fishing line - for preventing a rerun? Even if we're Hang Fours with solo and tandem aerotow proficiencies and Advanced Tandem Instructor appointments flying TWO point bridles and weak links in the MIDDLE of the legal range when we hit a bullet thermal at 150 feet we're fucked?
Is there some other flavor of aviation in which a certified aircraft in totally solid condition takes off in normal flying conditions with a highly qualified pilot who does nothing wrong but ends up with fatal injuries less than a minute later and no one can point to any real problem whatsoever?
USHGA Aerotow Guidelines
from the USHGA Safety and Training Committee
The FAA has granted the USHGA an exemption that allows aerotowing of hang gliders according to these guidelines. Aerotowing is a new and different way of flying hang gliders and must be done according to these guidelines for safety and legality.
II. AEROTOWING EQUIPMENT
THE AERO TUG: The ultralight used as a tug should have a wing loading so that its best climb speed is 25 to 38 mph (in thermal conditions, best climb speed must be over 30 mph). It must have enough power to tow a hang glider at a rate of climb of at least 300 feet per minute. The tug must have a concave rear view mirror so the tug pilot can see the glider at all times. The tug pilot should be able to operate the forward release without releasing the throttle or any of the flight controls.
THE AEROTOW GLIDER: The towed vehicle must meet or exceed the Hang Glider Manufacturers Association airworthiness standards.
THE AEROTOW BRIDLE: The tow bridle should be tested to a tension of 300 pounds and should release easily at that tension. It should also operate properly with zero tension and be constructed so that it cannot release accidentally. Aerotow bridles should be of a type approved by the manufacturer of the aero tug system or an aerotow instructor.
The United States Hang Gliding and Paragliding Association, Inc. - 2006/10
104 - Pilot Proficiency System
11. Hang Gliding Aero Tow Ratings
02. Aero Vehicle Requirements
-A. The tow vehicle (powered ultralight) must have a rated thrust of at least 250 lbs. -B. The towed vehicle (un-powered ultralight) must meet or exceed the Hang Glider manufacturers Association's Airworthiness Standards.
-C. The tow line connection to the towing vehicle must be arranged so as to not hinder the control system of the towing vehicle.
The United States Hang Gliding and Paragliding Association, Inc. - 2008/03
12. Standard Operating Procedure
02. Pilot Proficiency System
10. Hang Gliding Aerotow Ratings
-B. Aero Vehicle Requirements
01. The tow vehicle (powered ultralight) must have a rated thrust of at least 250 lbs. 02. The towed vehicle (un-powered ultralight) must meet or exceed the Hang Glider manufacturers Association's Airworthiness Standards.
03. The tow line connection to the towing vehicle must be arranged so as to not hinder the control system of the towing vehicle.
The United States Hang Gliding and Paragliding Association, Inc. - 2009/03
12. Standard Operating Procedure
02. Pilot Proficiency System
10. Hang Gliding Aerotow Ratings
-B. Aero Vehicle Requirements
01. The tow vehicle (powered ultralight) must have a rated thrust of at least 250 lbs. 02. The towed vehicle (un-powered ultralight) must meet or exceed the Hang Glider manufacturers Association's Airworthiness Standards.
03. The tow line connection to the towing vehicle must be arranged so as to not hinder the control system of the towing vehicle.
Tad Eareckson - 2009/10/27
Federal Aviation Administration
J. Randolph Babbitt
Administrator
800 Independence Avenue
AFS 810 Room 832J
Washington DC 20591-0001
02. The towed vehicle (un-powered ultralight) must meet or exceed the Hang Glider manufacturers Association's Airworthiness Standards.
The HGMA certifies gliders to strength, stability, performance, and control standards. A pilot within a specified weight range with both hands properly positioned on and securely gripping the basetube is an integral part of the glider and its control system. The instant a pilot removes a hand from the basetube all stability, performance, and control predictions and expectations are history. The action is analogous to momentarily severing the linkages to the ailerons, elevator, and rudder on a conventional aircraft. The glider can and often does become a leaf in the wind.
A release which requires a pilot to interrupt his grip on the basetube and thus control of the glider decertifies the craft.
Unlike sailplanes, the pilot is an integral part of the tow system.
The United States Hang Gliding and Paragliding Association, Inc. - 2011/05
12. Standard Operating Procedure
02. Pilot Proficiency System
12. Hang Gliding Aerotow Ratings
-C. USHPA Aerotow Equipment Guidelines
01. The tow vehicle must have a rated thrust of at least 250 lbs. ...............
02. The tow line connection to the towing vehicle must be arranged so as to not hinder the control system of the towing vehicle.
The United States Hang Gliding and Paragliding Association, Inc. - 2011/11
12. Standard Operating Procedure
02. Pilot Proficiency System
12. Hang Gliding Aerotow Ratings
-C. USHPA Aerotow Equipment Guidelines
01. The tow vehicle must have a rated thrust of at least 250 lbs. ...............
02. The tow line connection to the towing vehicle must be arranged so as to not hinder the control system of the towing vehicle.
03. A pilot operational release must connect the tow line to the towing vehicle. This release must be operational with zero tow line force up to twice the rated breaking strength of the weak link.
04. 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 100lbs. greater than the glider end.
05. 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.
06. The purpose of the weak link is to protect the tow equipment, and may not prevent lockouts or other abnormal flight conditions.
The United States Hang Gliding and Paragliding Association, Inc. - 2012/06/20
12. Standard Operating Procedure
02. Pilot Proficiency System
12. Hang Gliding Aerotow
-C. Aerotow Equipment Guidelines
01. The tow vehicle must have a rated thrust of at least 250 lbs. ...............
02. The tow line connection to the towing vehicle must be arranged so as to not hinder the control system of the towing vehicle.
03. A pilot operational release must connect the tow line to the towing vehicle. This release must be operational with zero tow line force up to twice the rated breaking strength of the weak link.
04. Weak links must be used in accordance with 14 CFR 91.309(a)(3). USHPA recommends that a nominal 1G (combined operating weight of the glider and pilot) weak link be used, when placed at one end of a hang glider pilot's V-bridle; or about 1.5-2G if placed at the apex of the tow bridle or directly in-line with the tow rope. The actual strength of the weak link used by the hang glider pilot must be appropriate for the operation and have a breaking strength between 80% and 200% MCOW (max. cert. operating weight) of the glider, in terms of direct towline tension. The weak link used at the tow plane end of the towline must be stronger, but not more than 25% stronger, than the strength of the weak link used at the glider end of the towline.
05. 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.
06. The purpose of the weak link is to protect the tow equipment, and may not prevent lockouts or other abnormal flight conditions.
Yesterday was a light and variable day with expected good lift. Zach was the second tow of the afternoon. We launched to the south into a nice straight in wind. A few seconds into the tow I hit strong lift.
Zach hit it and went high and to the right. The weak link broke at around 150 feet or so and Zach stalled and dropped a wing or did a wingover, I couldn't tell. The glider tumbled too low for a deployment.
Out of respect for friends and family, I'd ask that if you have a need to more, please call me directly at 585-737-9894 or email me privately instead of posting publicly.
Thank you
The United States Hang Gliding and Paragliding Association, Inc. - 2013/02/07
12. Standard Operating Procedure
02. Pilot Proficiency System
11. Hang Gliding Special Skill Endorsements
-D. Aerotow
http://www.ushpa.aero/safety.asp
USHPA - Safety Articles
Fatality Reports
Fatality Report 2013 (PDF)
Hang Gliding and Paragliding Fatalities Jan 2013 Through July 2013
Hang Gliding Fatalities
2013/02/02 - Zack Marzec
Zack Marzec (27), an H-4 Pilot with Aero Tow and Tandem Aero Tow proficiency as well as Advanced Instructor and Tandem Instructor appointments, and a USHPA member since 2009, suffered fatal injuries when when his glider tumbled during an aero tow launch. During the launch, at an altitude of 150 AGL, the pilot encountered an invisible bullet thermal which pitched the nose up, causing the weak link to break. Upon the breakage of the weak link, the glider whip stalled and then tumbled twice. The pilot and glider's leading edge hit the ground simultaneously. The pilot was utilizing his own pro-tow style tow harness, this own high performance glider with VG on, and was not wearing a full face helmet.
I was wondering why this football field sized invisible bullet thermal that knocked Zack Marzec...
Zack hit the lift a few seconds after I did. He was high and to the right of the tug and was out of my mirror when the weak ling broke. The load on the tug was not excessive as with a lockout, but I was not surprised when the weak link broke. I was still in the thermal when I caught sight of Zack again. I did not see the entry to the tumble, but I did see two revolutions of a forward tumble before kicking the tug around to land. The thermal was still active in the area that I had just launched from so I did a go round and landed on a runway 90 degrees cross to the direction we were towing in.
...a few seconds before - especially seeing as how Mark had no freakin' clue what he was flying into while Zack - from observing the tug - had about five seconds worth of advance notice concerning EXACTLY what he was about to fly into.
I thought it might have something to do with the differences between the two aircraft and how they were configured for towing operations and figured it would be a good idea to look at the USHGA/FAA regulations under which US aerotowing operations evolved.
Hang Gliding - 1985/07
USHGA Aerotow Guidelines
from the USHGA Safety and Training Committee
The FAA has granted the USHGA an exemption that allows aerotowing of hang gliders according to these guidelines. Aerotowing is a new and different way of flying hang gliders and must be done according to these guidelines for safety and legality.
I RATINGS
AEROTOW GLIDER PILOT: This is the rating that allows a pilot to be aerotowed without being observed by an aerotow instructor.
1) Must possess at least a USHGA Intermediate rating.
2) Demonstrate five aerotows under supervision of USHGA Certified Instructor qualified to teach towing. Each flight must demonstrate proper procedures, including smooth, clean launches, proper position in straight flight and turns.
3) Pilot must pass the oral test.
Until a pilot receives this rating, all aerotows must be sponsored by an under the guidance of an aerotow instructor.
AEROTOWING INSTRUCTOR: This is the rating that allows a pilot to teach other pilots to be aerotowed and to teach other pilots to be tug pilots.
1) Must hold a USHGA Instructor card for at least six months.
2) Successfully pass a towing instructor certification program, demonstrating capabilities in the form of aerotowed flights in different conditions and experience teaching pilots to be aerotowed.
TUG PILOT: This is the rating that allows a pilot to tow pilots with an aerotow rating or under the supervision of an aerotowing instructor. It is given by an aerotow instructor who has witnessed a pilot who has flown a minimum of ten aerotows, demonstrating proper procedures, including smooth takeoffs, straight flight and turns, and passed the oral test. Until a pilot receives this rating, all aerotows must be sponsored by and under the guidance of an aerotow instructor. A tug pilot cannot tow a pilot who has fewer than five tows.
II AEROTOWING EQUIPMENT
1) The tow line connection to the towing vehicle must be arranged so as not to hinder the control system of the towing vehicle.
2) A pilot-operational release must connect the tow line to the towing vehicle. This release must be operational with zero line force up to twice the breaking strength of the tow line.
3) A weak link must be placed between the tow line and the release at both ends of the tow line with the forward link ten percent stronger than the rearward weak link. The weak link must have a breaking strength less than 85% the weight of the hang glider and pilot combination, not to exceed 200 pounds.
4) 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 tow line.
5) A drogue device must be placed midway to 3/4 back from the tow vehicle on the tow line to prevent the tow line from reaching the tow vehicle propeller.
6) The tow line must be at least 150% as strong as the weak link in use.
THE AERO TUG: The ultralight used as a tug should have a wing loading so that its best climb speed is 25 to 38 mph (in thermal conditions, best climb speed must be over 30 mph). It must have enough power to tow a hang glider at a rate of climb of at least 300 feet per minute. The tug must have a concave rear view mirror so the tug pilot can see the glider at all times. The tug pilot should be able to operate the forward release without releasing the throttle or any of the flight controls.
THE AEROTOW GLIDER: The towed vehicle must meet or exceed the Hang Glider Manufacturers Association airworthiness standards. A pilot's first aerotowed flights should be with a glider familiar to the pilot with control bar wheels installed. A pitch enhancement device may be installed for improved pitch control on tow. Pitch devices must be installed and tuned according to the manufacturer's specifications. Extreme caution must be exercised when towing gliders possessing forward components that can contact the tow line (such as bowsprit gliders).
THE AEROTOW BRIDLE: The tow bridle should be tested to a tension of 300 pounds and should release easily at that tension. It should also operate properly with zero tension and be constructed so that it cannot release accidentally. Aerotow bridles should be of a type approved by the manufacturer of the aero tug system or an aerotow instructor.
III OPERATIONS
Aerotowing is complex and must be properly organized to be safe and efficient.
In practice, a particular site and weather pattern will have a standard routing and most pilots will know what to do. It is the launch director's responsibility to make sure everyone knows what to do. Considerations for establishing a routine include pilot skill, surface winds, winds aloft, runway direction, areas of turbulence, lift and sink, emergency landing zones to be used in case of line breaks or engine failures and separation between gliders, obstacles, tug and line.
PREFLIGHT PROCEDURES: Check the tug for adequate fuel supply. Preflight and test fly the tug. Preflight the line by stretching it out on the ground and inspecting its entire length including weak links, all knots, splices and fittings. Worn lines should be replaced.
AEROTOWING POSTFLIGHT PROCEDURE: The glider end of the rope should be checked for accidental knots and untied if necessary. Never tow with a knot in a line because they weaken the rope, cause premature wear and can be very difficult to untie.
The FAA has granted the USHGA an exemption that allows aerotowing of hang gliders according to these guidelines.
So these aren't really "guidelines". These are conditions we agreed to adhere to in order for the FAA to allow us the privilege of aerotowing. So they're actually regulations.
Aerotowing is a new and different way of flying hang gliders and must be done according to these guidelines for safety and legality.
Right. We "MUST" adhere to them - otherwise we're operating illegally. And that could be a serious issue if someone were to get killed as a direct consequence of a violation of these conditions. But, what the hell, probably best to refer to them as guidelines. A bit of ambiguity might come in handy some day.
The tow line connection to the towing vehicle must be arranged so as not to hinder the control system of the towing vehicle.
Sounds like a good idea. I like what Bobby's done with this Dragonfly here:
He has an attachment down on the end of the fuselage where the release is mounted and then an extension up from the rudder post to raise the upper attachment. Run a bridle between the two points and through a tow ring on the way. Then the towline centers and aligns with the tug's thrust line. Thus, as long as the glider's in reasonably good position, the tug handles pretty normally. Pure genius.
Same sorta thing they do when they use trikes for towing:
A pitch enhancement device may be installed for improved pitch control on tow. Pitch devices must be installed and tuned according to the manufacturer's specifications.
...pitch control is a bit of an issue. Shouldn't you just require an upper attachment point to keep the glider trimmed like the tug is?
How come you make absolutely no mention of the towline connection to the...
The tow line connection to the towing vehicle must be arranged so as not to hinder the control system of the towing vehicle.
...TOWED vehicle and minimizing its effect on the control system? Wouldn't it be pretty easy to have an upper connection?
By all accounts, Zack...
During the launch, at an altitude of 150 AGL, the pilot encountered an invisible bullet thermal which pitched the nose up, causing the weak link to break. Upon the breakage of the weak link, the glider whip stalled and then tumbled twice.
...had a major issue with pitch control and you seem to think that his...
The pilot was utilizing his own pro-tow style tow harness...
...pro-toad style harness was a significant part of the problem. And I totally agree. Even just coming off the cart...
...he has to keep the bar back about as far as he's physically capable of stuffing it. Seems like that could be a real issue if he were to get popped by an invisible bullet thermal.
A pilot-operational release must connect the tow line to the towing vehicle. The tug pilot should be able to operate the forward release without releasing the throttle or any of the flight controls.
Well yeah. No brainer. Goes without saying. I can't think of a single tug in the history of towing ANYTHING - hang gliders, sailplanes, military transport gliders - that didn't have THAT capability. When the shit's hitting the fan the ABSOLUTE *LAST* THING you wanna be doing is compromising control. And the glider's weak link only keeps IT from getting into too much trouble - not...
...obviously, the tug. It's perfectly OK to put the glider's release actuator...
A release must be placed at the hang glider end of the tow line within easy reach of the pilot.
...within easy reach of the pilot because if he (stupidly) fails to maintain the correct tow position (centered, with the wheels of the tug on the horizon), the weak link will break before he can get into too much trouble.
Or, hell, the tug pilot can cut him loose while he's in the process of executing the easy reach. Either way...
...he's good.
A weak link must be placed between the tow line and the release at both ends of the tow line with the forward link ten percent stronger than the rearward weak link. The weak link must have a breaking strength less than 85% the weight of the hang glider and pilot combination, not to exceed 200 pounds.
Max two hundred pounds? Are you sure? For me that's only about 0.6 Gs. That should REALLY keep me from getting into too much trouble - but it'll probably do so mostly by keeping me from getting into the air.
The tow line must be at least 150% as strong as the weak link in use.
Well YEAH! You want that thing to hold AT LEAST three hundred pounds. A towline break isn't like a weak link break - which increases the safety of the towing operation at the cost of a bit of inconvenience every now and then. A towline break is DANGEROUS! Towline breaks KILL people!
The ultralight used as a tug should have a wing loading so that its best climb speed is 25 to 38 mph (in thermal conditions, best climb speed must be over 30 mph). It must have enough power to tow a hang glider at a rate of climb of at least 300 feet per minute.
Yeah, power's important. You wanna get away from the ground pretty quick. After you get a couple hundred feet under you you're in pretty good shape to recover from shit like lockouts and towline breaks. Get up to a thousand or two and it's safe to practice recoveries from simulated weak link failures - as long as the air is smooth anyway.
The tug must have a concave rear view mirror so the tug pilot can see the glider at all times.
Wouldn't you get to see the glider at more times with a CONVEX mirror?
The tow bridle should be tested to a tension of 300 pounds...
Damn straight! A bridle failure can be just as deadly as a weak link failure.
...and should release easily at that tension.
How could we possibly find out? The weak link blew at two hundred or more pounds ago.
It should also operate properly with zero tension and be constructed so that it cannot release accidentally.
Why don't you stupid pigfuckers learn the difference between a BRIDLE and a RELEASE before you start writing aerotow regulations? Oh, never mind. It's not like the stupid pigfuckers at the FAA could give half a rat's ass about any of this anyway.
Aerotow bridles should be of a type approved by the manufacturer of the aero tug system or an aerotow instructor.
Just make sure the pin's bent. There isn't a manufacturer of an aero tug system or an aerotow instructor who will approve anything without...
Then again, Russell Brown had us double up behind him after six breaks in a row at Zapata. We couldn't figure out why we had so many breaks so quickly. Maybe just coincidence.
Jim Rooney - 2011/08/28 19:39:17 UTC
Weak links break for all kinds of reasons.
Some obvious, some not.
The general consensus is the age old adage... "err on the side of caution".
The frustration of a weaklink break is just that, frustration.
And it can be very frustrating for sure. Especially on a good day, which they tend to be. It seems to be a Murphy favourite. You'll be in a long tug line on a stellar day just itching to fly. The stars are all lining up when *bam*, out of nowhere your trip to happy XC land goes up in a flash. Now you've got to hike it all the way back to the back of the line and wait as the "perfect" window drifts on by.
I get it.
It can be a pisser.
But the "other side"... the not cautions one... is not one of frustration, it's one of very real danger.
Better to be frustrated than in a hospital, or worse.
No exaggeration... this is the fire that the "other side" is made of. Best not to play with it.
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).
Isn't safety the overriding concern here?
It is the launch director's responsibility to make sure everyone knows what to do. Considerations for establishing a routine include pilot skill, surface winds, winds aloft, runway direction, areas of turbulence, lift and sink, emergency landing zones to be used in case of line breaks or engine failures and separation between gliders, obstacles, tug and line.
So line breaks and engine failures are emergencies - but the heaviest weak link we can use is two hundred pounds.
Check the tug for adequate fuel supply.
Yeah, we sure don't want any engines sputtering on takeoff.
Preflight and test fly the tug. Preflight the line by stretching it out on the ground and inspecting its entire length including weak links, all knots, splices and fittings. Worn lines should be replaced.
Three hundred pound capacity - MINIMUM. (If it's a happening day and your pressed for time you're really OK until you start getting down towards two hundred but try not to make a habit of it.
The glider end of the rope should be checked for accidental knots and untied if necessary. Never tow with a knot in a line because they weaken the rope, cause premature wear and can be very difficult to untie.
Wow! Never thought of that! Sounds like you've really gotta keep track of a lot of things - engine warm-up, fuel reserve, release reliability, towline and bridle construction and condition, towline knotting - to make sure the glider can safely tow up and not be put into an emergency situation. You guys sure seem to have thought of everything and I'll definitely sleep a lot easier knowing that we've got highly qualified people overseeing these operations.
I think I figured out why Mark flew through the invisible bullet thermal with absolutely nothing in the way of a problem while Zack ended up in a terminal heap back on the runway. Everything in the regulations, guidelines, implementation, regular practice is geared toward giving the tug:
- adequate, reliable, uninterruptable power
- uninterruptable and close to normal control
- ability and carte blanche to dump the glider:
-- in the blink of an eye
-- at any whim
- a weak link unlikely to retain the glider on tow through the slightest upwards fluctuation of tension
while the glider is permitted, encouraged, forced to fly with:
- virtually no expectation of adequate, reliable, uninterruptable power
- highly compromised control and stability
- no ability whatsoever to abort the tow in an emergency
- a weak link unlikely to retain the glider on tow through the slightest upwards fluctuation of tension
Not the least bit surprising that this crap was authored by the "USHGA Safety and Training Committee" with no actual names of anyone revealed. No surprise whatsoever that from the very start aerotowing has been geared entirely towards protecting the commercial operators to the maximum extent possible from physical dangers and accountability while the gliders are treated as nothing more than expendable ballast.
Yes, this is very much about safety. What happened at Quest last month has only reinforced my position.
Jim Rooney - 2013/03/05 19:42:58 UTC
My god my head hurts.
Wow...
So you know what happened then?
OMG... thank you for your expert accident analysis. You better fly down to FL and let them know. I'm sure they'll be very thankful to have such a crack expert mind on the case analyzing an accident that you know nothing about. Far better data than the people that were actually there. In short... get fucked.
Again, tell me how all this nonsense is about "safety"?
So, a stronger weaklink allows you to achieve higher AOAs... but you see high AOAs coupled with a loss of power as *the* problem? So you want something that will allow you to achieve even higher AOAs?
Are you NUTS?
I'm tired of arguing with crazy.
As I said many times... there are those that listen with the intent of responding... you unfortunately are one.
You've done a great job of convincing me never to tow you.
Thank you for that.
Mission accomplished.
You're the one advocating change here, not me.
I'm fine.
These are only questions if you're advocating change. Which I'm not. You are.
You're the one speculating on Zack's death... not me.
Hell, you've even already come to your conclusions... you've made up your mind and you "know" what happened and what to do about.
It's disgusting and you need to stop.
You weren't there. You don't know.
All you have is the tug pilot report, who himself says he doesn't know... and HE WAS THERE... and he doesn't know.
Ever heard of "Confirmation Bias"?
Because you're a textbook example.
You were out looking for data to support your preconceived conclusion, rather than looking at the data and seeing what it tells you... which is why this is the first time we've heard from you and your gang.
Go back to Tad's hole in the ground.
While you're there, ask him why he was banned from every east coast flying site.
Hey Jim...
http://www.ushpa.aero/safety.asp
USHPA - Safety Articles
Fatality Reports
Fatality Report 2013 (PDF)
Hang Gliding and Paragliding Fatalities Jan 2013 Through July 2013
Hang Gliding Fatalities
2013/02/08 - Zack Marzec
Zack Marzec (27), an H-4 Pilot with Aero Tow and Tandem Aero Tow proficiency as well as Advanced Instructor and Tandem Instructor appointments, and a USHPA member since 2009, suffered fatal injuries when when his glider tumbled during an aero tow launch. During the launch, at an altitude of 150 AGL, the pilot encountered an invisible bullet thermal which pitched the nose up, causing the weak link to break. Upon the breakage of the weak link, the glider whip stalled and then tumbled twice. The pilot and glider's leading edge hit the ground simultaneously. The pilot was utilizing his own pro-tow style tow harness, this own high performance glider with VG on, and was not wearing a full face helmet.
So, after six months worth of exhaustive investigation on this unfortunate event and consultation with the best minds in the business it seems that we actually DO have definitive conclusions about what happened and what to do about it.
Although, obviously as a consequence of an oversight, there are no names attached to this document, we can make some no brainer assumptions about the individuals who authored it, were consulted in its preparation, approved it.
--- Mitch Shipley
Mitchell Shipley - 47131 - H4 - 1990/06/09 - Jim Woodward
- AT FL ST TAT TFL TPL TST 360 AWCL CL FSL RLF TUR XC
- ADV INST, AT ADMIN, PL ADMIN, ST ADMIN, TAND INST
Personable and fun, Dr. Mitch Shipley excels at flying - and at whatever else he decides to do, too. He's been hang gliding since 1987 and competed actively from 1995-2002. He flew more than 100 hours and 1000-2000 cross country miles each of those years, racking up numerous accolades and site records. He began flying tandem in 1997 so he could take his sons with him into the sky. He's introduced many others to the joys of hang gliding since, and is a gifted, empathetic and thorough instructor.
This overachiever graduated from the United States Naval Academy and completed a 21 year naval career in submarines and submarine related research. He rides dirt bikes, boasts 500 sky-dives and routinely crushes his age group in running and triathlon races.
He's also a devoted father who dotes on "his boys."
Are you surprised that he flies the tow plane, too? I didn't think so.
Well, I'm a LITTLE surprised that he flies the tow plane, too - seeing as how USHGA doesn't list him as being rated to do so.
But, wait a minute, Quest doesn't actually say he TOWS anyone with the tow plane - just that he FLIES it. How could I have been so stupid as to make a totally bogus assumption like that?
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).
Enjoy your posts, as always, and find your comments solid, based on hundreds of hours / tows of experience and backed up by a keen intellect/knowledge of the issues when it comes to most things in general and hang gliding AT/Towing in particular. Wanted to go on record in case anyone reading wanted to know one persons comments they should give weight to.
...the one person whose comments everyone should give the most weight to - tons of experience, keen intellect, knowledge of the issues when it comes to most things in general and aerotowing in particular.
James Rooney - 78142 - H4 - 2004/09/03 - Sunny Venesky
- AT FL LGO PL ST TAT TFL RLF TUR XC
- AT ADMIN, TAND INST, TUG PILOT
In the old threads there was a lot of info from a guy named Tad. Tad had a very strong opinion on weak link strength and it was a lot higher than most folks care for. I'd focus carefully on what folks who tow a lot have to say. Or Jim Rooney who is an excellent tug pilot. I tow with the "park provided" weak links. I think they are 130 pound Greenspot.
...130 pound Greenspot.
--- Steve Wendt
Steve Wendt - 19528 - H4 - 1984/02/06 - John Harris
- AT FL TAT TFL TPL TST AWCL CL FSL RLF TUR XC
- ADV INST, AT ADMIN, EXAM, PL ADMIN, ST ADMIN, TAND INST
The Master of the form is Steve Wendt at Blue Sky. http://www.blueskyhg.com/
Talk to him before you do ANYTHING.
...the master of the form...
Davis Straub - 2012/04/03 20:48:29 UTC
Steve Wendt is the man.
...the man. Really understands the extreme danger of...
Wills Wing / Blue Sky / Steve Wendt / Ryan Voight Productions - 2007/03
NEVER CUT THE POWER...
Reduce Gradually
Increase Gradually
...cutting the power - as well as the paramount importance of...
Blue Sky Scooter Towing
Scooter Tow Video
More Details on Equipment:
V-Bridle/Release System
But with the towline we use a standard weak link like we would for aerotow... Uh... This... In this particular case it's 130 greenline, 130 pound test.
...the standard 130 pound test greenline weak link we use for aerotow.
---- Bobby Bailey
Robert Bailey - 78665 - 2006/12/31 - H4 - Russell Brown - 2002/02/13
- AT FL PL RLF TUR XC
- AT ADMIN, TUG PILOT
The word most often associated with Bobby Bailey is genius. He's a gifted tow pilot, regarded as one of the best if not the best in the world. He's a gifted aircraft designer as well, building his first hang glider at the age of 18. He designed the Moyes-Bailey Dragonfly tug that sets the standard for towing hang glider pilots worldwide, and in 1995, received a Presidential Citation from the United States Hang Gliding Association - its highest honor - for his history of contribution to the sport of hang gliding through the development and promotion of aerotowing technology.
In 2003, he was inducted into the Rogallo Foundation Hall of Fame for his contribution for the betterment of safety, progress, recognition, promotion, growth and development of low speed flight and the design and development of the Moyes Bailey tug. In 2008, his homebuilt glider won the Red Bull Flugtag in Tampa.
Currently, he is partners with Bill Moyes in Liteflite and spends his winters in Australia.
Is applauded for his efforts to improve the safety of aerotowing by using the better weak link material...
Davis Straub - 2008/04/22 14:47:00 UTC
Hughenden Airport, Queensland
What material should be used for weaklinks?
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.
...which prevented Zack from achieving an even more dangerous pitch-up when he encountered the invisible bullet thermal.
Thought I already answered that one... instead of quoting myself (have a look back if you don't believe me), I'll just reiterate it.
I don't advocate anything.
I use what we use at the flight parks. It's time tested and proven... and works a hell of a lot better than all the other bullshit I've seen out there.
130lb greenspot (greenspun?) cortland fishing line.
In stock at Quest, Highland, Eastern Shore, Kitty Hawk Kites, Florida Ridge, and I'm pretty sure Wallaby, Lookout and Morningside.
Not sure what Tracy up at Cloud Nine uses, but I'll put bets on the same.
Did I miss any?
Is it clear what I mean by "We"?
I didn't make the system up.
And I'm not so arrogant to think that my precious little ideas are going to magically revolutionise the industry.
There are far smarter people than me working this out.
I know, I've worked with them.
(Bobby's a fucking genius when it comes to this shit... for example.)
Once the glider bounces off the ground, Robin is never able to get the glider lined up correctly behind Bobby Bailey and drifted continually to the left, locking out and crashing from a low altitude. If Bobby had released Robin at any time before the last two or three seconds he would likely not have crashed, at least not from a lockout.
Remember that Robin's bridle and weaklink failed. He attempted to release and was unable to do so.
...has also used a Dragonfly to tow a highly experienced and qualified hang glider pilot to a totally predictable death on shit Bobby Bailey designed equipment.
--- Mark Frutiger
Mark Frutiger - 21495 - H4 - 2003/04/24 - Doug Mossbrook
- AT FL TAT CL RLF TUR XC
- BAS INST, EXAM, TAND INST, TUG PILOT
Zack hit the lift a few seconds after I did. He was high and to the right of the tug and was out of my mirror when the weak ling broke. The load on the tug was not excessive as with a lockout, but I was not surprised when the weak link broke. I was still in the thermal when I caught sight of Zack again. I did not see the entry to the tumble, but I did see two revolutions of a forward tumble before kicking the tug around to land. The thermal was still active in the area that I had just launched from so I did a go round and landed on a runway 90 degrees cross to the direction we were towing in.
Excellent understanding of just how important the Rooney Link is in keeping both glider and tug from getting too far out of whack.
--- Bill Moyes
It all started with The Birdman himself - the legendary Bill Moyes, when in 1967 he astounded aeronautical experts by flying his wing to 1045 feet over Lake Tuggerah and set the first world altitude record - incredibly, only six weeks after he began flying.
Australian engineer John Dickenson had read of a wing NASA had developed to replace the steerable parachute for rocket re-entries and built the first flying wing that we fly today, with Bill as test pilot - at this stage being towed by a motor boat.
In 1968 Bill extended the altitude record to 2870 feet on Lake Ellesmere, New Zealand.
This may have been enough for some but Bill had always dreamed of running to a rock ledge and flying away with a pair of wings. He was convinced that it could come true. It was just a matter of finding the right set of wings.
So, in 1968, with the right set of wings, Bill foot-launched his glider from Mount Crackenback in the Australian Alps, setting the first world record for unassisted launched flight, and from that moment on pioneered and developed the sport of hang gliding we know and love today.
Bill never anticipated when he first flew off the mountains that it would explode as a sport, but it wasn't too long before friends began asking Bill to build them a hang glider. He made twelve gliders for friends in the first year, perfecting and refining as he went along and with twenty orders in the second year, Moyes Delta Gliders was born.
Throughout the 1970s, Bill continued to push the boundaries of flight, making the First Grand Canyon Flight in 1970. Then, having developed his wings further so they were capable of high speed, made the First Aeroplane Tow in 1971, setting a new altitude record of 8610 feet. And in 1972, after his water-tow altitude record had been broken by an American, Bill returned to New Zealand to raise the altitude to 4750 feet and regained the world record. He also won the North American Championships despite recovering from a broken pelvis from an earlier accident and still walking on crutches!
1973 saw Bill set yet another altitude record by being lifted with a hot air balloon and dropped from 10,700ft - then gliding for a record 13.7 miles.
Finally in 1974, Bill retired from the competition circuit, to focus his significant experience and expertise on glider design and development. He still flies recreationally and is invited to every international event - and is involved with the organisation of many of these.
Bill continues to influence the sport and has gained worldwide recognition for his incredible contribution to sport and aviation, including this prestigious list of honours:
1977 - Silver Medal - Queen Elizabeth Anniversary Medal
1978 - Bronze Medal - Russan Aero Club
1980 - Oswald Watt Gold Medal - Royal Australian Aero Club
1980 - Plaque - NSW Hall of Champions
1982 - Advance Australia Award - NSW Government
1992 - Associate Member - Australian Sports Hall of Fame
1995 - Hall of Fame - NASA Space Technology
1995 - Invention Award - Smithsonian Institute
1998 - OAM - Medal of the Order of Australia
2000 - Contribution to Sport - Australian Sports Medal
Where Quest and all of its crazy fun started is with co-founders and owners Russell Brown and Campbell Bowen. Russell is an ace tandem instructor and tug pilot as well as Quests's chief mechanic. Campbell, a past national hang gliding champion, tandem instructor and tug pilot, is still a fierce competitor who can usually be found at the top of a thermal.
Quest co-founders and owners, experts on crazy fun.
Russell Brown - 53035 - H4 - Rick Jacob - 1993/08/30
- AT PL ST TAT TFL TPL TST AWCL CL FSL RLF TUR XC
- AT ADMIN, AT SUP, PL ADMIN, ST ADMIN, TAND ADMIN, TAND INST, TUG PILOT
Dr. Trisa Tilletti - 2012/06
Russell Brown, a founder of Quest Air in Florida and a well-known Dragonfly tug pilot, is also a sailplane pilot, tug pilot, and A&P mechanic for a large commercial sailplane towing operation in Florida. He told us that, like us, he has never seen a sailplane weak link break, either. Russell owned the first 914-powered Dragonfly ever made--he helped us build the second one, which we still fly. He is the one who, many years ago, showed us the method for making a WT weak link and suggested we use polypropylene rather than Spectra for hang glider V-bridles.
Then again, Russell Brown had us double up behind him after six breaks in a row at Zapata. We couldn't figure out why we had so many breaks so quickly. Maybe just coincidence.
Knows how to get the job done when the chips are down.
Davis Straub - 2011/08/26 14:04:52 UTC
Russell Brown (tug pilot, tug owner, Quest Air owner) said go ahead and double up (four strands of Cortland Greenspot). He knows I used his Zapata weaklink in Big Spring (pilots were asked to tell the tug pilot if they were doing that).
(Just make sure you let him know that you wanna get the job done too.)
Campbell Bowen - 41614 - H5 - 1996/06/20 - Matthew Taber
- AT FL AWCL CL FSL RLF TUR XC
- PL SUP, TUG PILOT
Campbell knows all about the tops of thermals and, undoubtedly, the...
I got clobbered and rolled hard right in a split second. 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.
Understands that of all the equipment Quest Air has been perfecting for twenty years nothing is more important than 130 pound test fishing line. It's your only hope for getting off tow in a lockout at altitude.
--- Lauren Tjaden
Quest Air Hang Gliding - Eminently Qualified Tandem Pilot
Lauren Tjaden - 78079 - H4 - 2005/03/03 - Steve Kroop
- AT FL LGO TAT RLF TUR XC
- MNTR
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.
For whomever asked about the function of a weak link, it is to release the glider and plane from each other when the tow forces become greater than desirable -- whether that is due to a lockout or a malfunction of equipment or whatever. This can save a glider, a tow pilot, or more often, a hang glider pilot who does not get off of tow when he or she gets too far out of whack.
I rarely break weak links -- in fact, I believe the last one was some two years ago, and I have never broken one on a tandem (probably because I am light and also because I change them whenever they show any signs of wear). They are a good thing to have, though!!
Knows that the purpose of the weak link is to save a hang glider pilot who does not get off of tow when he or she gets too far out of whack but makes sure that it's changed whenever it shows any signs of wear so it will allow her to get a little bit out of whack without being inconvenienced before she can get back solidly in whack.
Lauren Tjaden - 2003/12/14
This fall at Ridgely, I had a weak link break at maybe fifty feet. I thought I was going to have to land in the soybeans - the very tall soybeans - when I looked at my angle. But, my glider stalled quite dramatically almost instantly (hard not to stall when you have a break), and dove towards the ground (a bit disconcerting from so low).
Your weak link comments are dead on. I have been reading the weak link discussion in the Oz Report with quiet amusement. Quiet, because weak links seem to be one of those hot button issues that brings out the argumentative nature of HG pilots and also invokes the "not designed here" mentality and I really did not want to get drawn into a debate. Amusement, because I find it odd that there was so much ink devoted to reinventing the wheel. Collectively I would say that there have been well over a 100,000 tows in the various US flight parks using the same strength weak link with tens of thousands of these tows being in competition. Yes I know some of these have been with strong links but only the best of the best aerotow pilots are doing this.
Should the tandem glider become unattached from the tug during this maneuver, the nose high attitude of the tandem glider attained while doing this will cause a very abrupt stall which will result in a much greater altitude loss than one would expect (possibly more than 750 feet). The most extreme cases may result in structural failure of the glider.
Towing tandems requires extra awareness on the part of the tug pilots, particularly in the early part of the tow to help the tandem pilot avoid the development of critical situations. Prior to the start of the tow, proper tow speeds based on the gross weight of the tandem glider should be determined. Greater total weight will require correspondingly higher tow speeds. It is CRITICAL to understand that the towed hang glider is at risk when the tow is slow and the glider is low. When towing a tandem glider, the tug pilot should fly the appropriate airspeed to keep the tandem glider in the proper position and if there is any doubt the tug pilot should fly slightly faster and avoid flying slightly slow. The tug pilot should avoid pulling up abruptly and leaving the tandem glider low. If the glider is low on tow, the tug pilot should attempt to speed up and to descend to the altitude of the towed glider, releasing the tow rope only as a last resort.
These points are crucial to the safety of aerotow tandem flight. However, this letter is addressed to all aerotow rated pilots and tug pilots, not just to tandem pilots. This is because in consulting with pilots about this issue, we found that this problem is exhibited under the same circumstances with solo gliders as well. Because of the lighter wing loading of the solo gliders, the reaction of a solo glider is not as severe, but can still be violent.
Flying with a tandem passenger is a special privilege which the FAA allows us to grant to qualified pilots. These pilots are supposed to be highly skilled. We expect tandem flights to be safer than solo flights, not more dangerous. Safety records do not currently seem to support this expectation. We expect tandem flights under the rules of the USHPA to be conducted in such a way that this expectation is realized.
--- Dr. Trisa Tilletti
USHGA Towing Committee Chairman
Tracy Tillman - 29852 - H4 - 1997/09/16 - Russell Brown
- AT FL LGO PL TAT TST VA AWCL CL FSL RLF TUR XC
- ADV INST, AT ADMIN, AT SUP, EXAM, INST ADMIN, ST ADMIN, TAND ADMIN, TAND INST, TUG PILOT
Lisa Colletti - 65433 - H4 - 1998/10/04 - Tracy Tillman
- AT FL LGO PL ST TAT PA VA AWCL CL FSL RLF TUR XC
- ADV INST, AT ADMIN, TAND INST, TUG PILOT
I'm Tracy Tillman, on the USHPA BOD, on the Tow Committe, and I am an Aviation Safety Counselor on the FAA Safety Team (FAAST) for the Detroit FSDO area. As a rep of both the USHPA and FAA, I would like to help you, USHPA, and the FAA improve safety in flying, towing, and hang gliding.
The FAA gets a lot of letters of complaint from a lot of yahoos. For best effect, I suggest that you describe in your letter (and also post to the skysailingtowing group and share with the USHPA Tow Committee) your areas of expertise (if any) related to this issue, and list your qualifiications, logged hours, and currency in certain categories, such as:
1. hang glider pilot rating and logged hours
2. hang glider aerotow rating, logged hours, and logged number of tows
3. hang glider tug pilot rating, logged hours towing, and logged number of tows
4. hang glider aerotow administrator appointment date
5. hang glider aerotow supervisor appointment date
6. hang glider tanderm instructor rating, logged hours of aerotow tandem instruction, and logged number of instructional flights
7. airplane pilot license ratings and logged number of hours
8. airplane tow pilot endorsement date, logged number of hours towing with airplane, logged number of tows
9. sailplane tow pilot license ratings, logged number of hours, logged number of tows.
10. sailplane instructor license date, logged number of hours of instruction, logged number of instructional tows
11. any other flying or engineering-related credentials that you may have as evidence of your competence to make these claims.
(BTW, if you have an AT hang glider rating or above the you would/should have received the USHPA Aerotow Guidelines as part of your instruction from the person who taught you to aerotow and/or gave you your AT rating, and you should currently have access to them via the packet that is accessible to you on the USHPA web site, if your AT or higher AT-related ratings and appointments are current.)
It would also be good for the FAA and USHPA to know what kind of ultalight or sport plane tug and airplane you use for towing hang gliders and sailplanes with at your operation (if any), along with a general description of your towing operation or who you provide towing and instructional services for (if any).
Additionally, if you want to really present a convincing argument, you should also: (a) get other experts to co-sign your letter, such as those who have some or most of the aerotowing-related credentials listed above, who have been doing this for many years with many students, and who support your argument; and (b) present reliable data based on valid research showing that there is a significant difference in safety with the changes that you recommend. Supportive comments from aerotow experts along with convincing data can make a difference. Otherwise, it may seem as if your perception of "the sky is falling" may not be shared by most others who have a wealth of experience and who are deeply involved in aerotowing in the US.
This information would also be very helpful in convicing the USHPA and others to take your complaint seriously. Most of the individuals who serve on the USHPA Towing Committe have most of the credentials listed above, so it will be great for you to let them know about your similar credentials and depth of experience, too. If you do not have those credentials, it will be a simple matter for the USHPA Tow Committee to respond to the FAA to discount your complaint, so it will be very important for you to present this information in your letter to the FAA and to others now.
The best way to make change is to get involved, and join the Tow Committee at its meetings. That's what people who really care do to make change. Such is the nature of the great opportunities we have to make a difference in the US (although it means having to spend time, money, and effort, compared to the ease of just sitting in front of a computer.)
Good luck with your endeavor, and regards,
Dr. Tracy Tillman
USHPA Director, Region 7
FAA Detroit FSDO FAAST Aviation Safety Counselor
Author of the "Higher Education" series of magazine articles on...
Did anyone here bother to read Drs. Lisa Colletti and Tracy Tillman's thirteen page idiotic article in the June issue of USHPA's worthless magazine?
NMERider - 2012/06/06 03:25:09 UTC
You are being much too complimentary IMHO. I got so nauseated reading it I had to take a breather. Do you mean to tell me they wrote an article that wasn't insipid and self-congratulatory to the extreme? I've found their entire series on aerotowing to come off rather poorly to say the least. A sad waste of such exalted and highly qualified medical professionals. How do I know this? Well they won't stop patting each other on the back about how great they both are. Pardon me while I puke.
Larry Jorgensen - 2011/02/17 13:37:47 UTC
Air Adventures NW
Spanaway, Washington
It did not come from the FAA, it came from a USHPA Towing Committee made up of three large aerotow operations that do tandems for hire.
Appalling.
...aerotow operation that does tandems for hire.
--- Dr. Lionel D. Hewett
Dr. Trisa Tilletti - 2012/06
Dr. Lionel D. Hewitt, professor of physics and developer of the 2-to-1 center-of-mass Skyting bridle for surface towing, is well respected for his knowledge of towing, bridles, and weak links. His position on weak link strength for aerotowing of hang gliders seems to be consistent with ours. He has acknowledged that we especially need to avoid inadvertent weak link breaks while aerotowing, because much of aerotowing takes place over unlandable terrain. That, along with recognizing that towing pressures vary considerably while on aerotow, has led him to suggest the use of a weak link that breaks in the neighborhood of 1.5G of towline pressure. This is near to what actually results when a USHPA-recommended nominal 1G weak link is placed at the top end of a V-bridle used for aerotowing.
Well respected for his knowledge of towing, bridles, and weak links.
His position on weak link strength for aerotowing of hang gliders seems to be consistent with Dr. Trisa Tilletti's.
He has acknowledged that we especially need to avoid inadvertent weak link breaks while aerotowing, because much of aerotowing takes place over unlandable terrain - like this:
That, along with recognizing that towing pressures vary considerably while on aerotow, has led him to suggest the use of a weak link that breaks in the neighborhood of 1.5 Gs of towline pressure - is near to what actually results when a USHPA-recommended nominal 1G weak link is placed at the top end of a V-bridle used for aerotowing and half a G over what Zack was using with his pro toad bridle.
And...
Donnell Hewett - 1980/12
Now I've heard the argument that "Weak links always break at the worst possible time, when the glider is climbing hard in a near stall situation."
...Donnell has heard the argument that "Weak links always break at the worst possible time, when the glider is climbing hard in a near stall situation."
--- Felipe Amunategui
USHGA Towing Committee Chairman
Felipe Amunategui - 34743 - H4 - 1994/06/03 - Mike Del Signore
- AT FL PA AWCL CL FSL RLF TUR XC
- AT ADMIN, AT SUP, EXAM, TUG PILOT
Felipe Amunategui - 1996/12
A Tribute To Mike Del Signore
The day before the accident was clear, and in the still air sunrise Bill towed me to 4,000 feet AGL. It was a beautiful and peaceful ride down. We spent the rest of the day towing, and at the end of the day Bill, Mike and I discussed tandem tow procedures and regulations. We also practiced the whole procedure simulating the tow by hanging from a tree. I had things to do the next day, so I would not make my tandem flights until the next weekend. That evening was the last time I saw of my friends Mike and Bill. The following evening things changed horribly for all of us whose lives had been touched by them.
It took a while before I could get under a wing again, and some of our fellow pilots may never do so after this. We all react to tragedy in our own way. I knew Mike well, and I am certain that he would have never wanted to discourage others from flying safely, yet I know he would have respected each one's decision and ways of dealing with the pain. Also, I am certain that Mike would want us to learn how to avoid a similar tragedy. We owe it to Mike and Bill to further refine aerotowing in general and tandem towing in particular. Mike left us a legacy in the form of a community of hang glider pilots where there had been none, a community that helped its members ease the pain of his departure. We owe it to him to keep it alive.
A few weekends ago I flew Mike's personal glider from Spruce Knob, Bill's home site. Throughout the flight Mike and Bill were foremost in my mind. Circling in light lift over a majestic fall landscape I was saddened by the realization that the skies are lonelier without my friends. I took comfort in knowing that through Mike's legacy I will always be able to visit the sacred space he made accessible to us.
Tireless advocate of increasing aerotowing safety.
--- Bruce Weaver
Kitty Hawk Kites
- Hang Gliding School Manager
- Vice President of Recreation
This past weekend, Zack Marzec, a beloved hang gliding instructor at Kitty Hawk Kites passed away in a hang gliding accident in Florida at the age of 27. Zack had been with the company for nearly four years and was planning to return this coming season.
Zack Marzec started his career with the company as a dune hang gliding instructor and worked his way up to a tandem hang gliding instructor. Zack's positive attitude and passion for flying impacted many of the instructors and the students he taught during his time at Kitty Hawk Kites. Zack was the type of person who never met a stranger and always encouraged people to try new things. His love of flying and teaching was an inspiration and an example for those new to the sport.
Bruce Weaver, Vice President of Recreation and Manager of Kitty Hawk Kites Hang Gliding School said, "Zack started teaching hang gliding for us in 2009, when he won the title "Rookie of the Year". He spent the next three years teaching and flying, most recently as a tandem instructor at the airport and at Morningside Flight Park in Charlestown, New Hampshire. He had a passion and a gift for flying and teaching and truly lived his life to the fullest. His positivity and enthusiasm were contagious and he enriched the lives of the thousands of people he taught and of all those who knew him. We will miss him greatly."
Our deepest sympathies are sent to the family and friends of Zack Marzec. We have lost an amazing member of our team this weekend and we hold onto the many memories Zack gave us during his time at Kitty Hawk Kites. Fly, Fly, Fly.
Pilots 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.
Competitors must use appropriate aerotow bridles as determined by the Meet Director and Safety Director and their designated officials.
Weaklinks
Pilots 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.
For a couple of years I have flown with a doubled weaklink because, flying with a rigid wing glider, I have found that there is little reason to expect trouble on tow, except from a weaklink break.
Flies with a doubled weak link because he's found that there is little reason to expect trouble on tow - except from a weak link break.
Davis has been at an around all this plenty long enough to understand what's what and who's who.
--- Dennis Pagen
Coauthor of the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden. Top authority on the focal point...
Towing Aloft - 1998/01
A weak link is the focal point of a safe towing system.
A weak link is a very simple device--typically a loop of line--that is intended to break in the event towline tensions exceed a safe or desired threshold.
A weak link is required that will not break needlessly in response to moderate thermals, or pilot inputs, yet will break at a low enough point to avoid disaster or excessive pilot panic.
"It is infinitely better to have a weak link break too soon rather than too late."
-- Towing Proverb
A weak link is a fuse that protects the equipment--your body!--on an overloaded circuit.
Always use a weak link when towing--WEAK LINKS SAVE LIVES.
Of course, your weak link should break before the lockout becomes too severe, but that assumes a properly applied weak link.
...of a safe towing system.
Expert on conditioning the tug pilot...
Pro Tip: Always thank the tug pilot for intentionally releasing you, even if you feel you could have ridden it out. He should be given a vote of confidence that he made a good decision in the interest of your safety.
...to always act in the interest of our safety.
Excellent understanding of...
Lockouts do not just magically happen to snatch a glider from the sky. They are generally progressive events originating from situations that can usually be terminated. The pilot and tow team must recognize these situations and the potential for acceleration into full lockout conditions so they can take appropriate corrective action prior to occurrence. To recognize the potential conditions for a lockout, we need to understand how they work.
...lockouts...
Bill Bryden - 2000/02
Dennis Pagen informed me several years ago about an aerotow lockout that he experienced. One moment he was correcting a bit of alignment with the tug and the next moment he was nearly upside down. He was stunned at the rapidity. I have heard similar stories from two other aerotow pilots.
...and their progression and how to avoid them.
Solid background in pro toad bridles...
Hang Gliding - 2005/01
Dennis Pagen - SUMMER 2004 ACCIDENT REPORTS
FATAL TOWING ACCIDENT
The first accident occurred in Germany at an aerotowing competition. The pilot launched with his Litespeed and climbed to about forty feet when he encountered a thermal that lifted him well above the tug. After a few moments, the glider was seen to move to the side and rapidly turn nose down to fly into the ground, still on tow, in a classic lockout maneuver. The impact was fatal.
This pilot was a good up-and-coming competition pilot. He had been in my cross-country course three years ago, and this was his second year of competition. What happened to him is not too unusual or mysterious. He encountered so much lift that although he was pulling in the base bar as far as he could, he did not have enough pitch-down control to get the nose down and return to proper position behind the tug. This situation is known as an over-the-top lockout.
I am personally familiar with such a problem, because it happened to me at a meet in Texas. Soon after lift-off the trike tug and I were hit by the mother of all thermals. Since I was much lighter, I rocketed up well above the tug, while the very experienced tug pilot, Neal Harris, said he was also lifted more than he had ever been in his heavy trike. I pulled in all the way, but could see that I wasn't going to come down unless something changed. I hung on and resisted the tendency to roll to the side with as strong a roll input as I could, given that the bar was at my knees. I didn't want to release, because I was so close to the ground and I knew that the glider would be in a compromised attitude. In addition, there were hangars and trees on the left, which is the way the glider was tending. By the time we gained about 60 feet I could no longer hold the glider centered--I was probably at a twenty-degree bank--so I quickly released before the lockout to the side progressed. The glider instantly whipped to the side in a wingover maneuver. I cleared the buildings, but came very close to the ground at the bottom of the wingover. I leveled out and landed.
Analyzing my incident made me realize that had I released earlier I probably would have hit the ground at high speed at a steep angle. The result may have been similar to that of the pilot in Germany. The normal procedure for a tow pilot, when the hang glider gets too high, is to release in order to avoid the forces from the glider pulling the tug nose-down into a dangerous dive. This dangerous dive is what happened when Chris Bulger (U.S. team pilot) was towing John Pendry (former world champion) years ago. The release failed to operate in this case, and Chris was fatally injured. However Neal kept me on line until I had enough ground clearance, and I believe he saved me from injury by doing so. I gave him a heart-felt thank you.
The pilot in the accident under discussion was an aerodynamic engineer. He had altered his glider by lengthening the front cables and shortening the rear cables to move his base tube back. The amount was reportedly ten centimeters, or about four inches. This is well within the acceptable range, according to Gerolf Heinrichs, the Litespeed designer. Why the pilot altered his bar position in this manner is anyone's guess, but my guess is that it was because he felt the bar was too far out on the glider with the VG off. This Litespeed was the pilot's first topless glider and I expect he wasn't informed that most of the new topless gliders experience a great movement of the base tube as the VG is pulled through its range. The result is that the bar is so far out and the pitch pressure so strong that with the VG off, that the standard procedure is to take off and land with at least a quarter VG. If the pilot didn't know this he would have been tempted to move the bar.
Factors that attributed to the accident in various degrees were the pilot's experience, the conditions and the alteration of the base tube. To begin, he wasn't greatly experienced in aerotowing, although he had learned and spent much of his flying with surface tow. It is difficult to assess the effect of the turbulence, but suffice it to say that it was strong enough to project him upward, well above the tug. Finally, the alteration of the basetube position could have been a contributing factor because he certainly would have had more pitch authority if he hadn't done that. It is impossible to tell, but perhaps the thermal that lifted him would not have done so as severely if he had had a bit more pitch travel.
What We Can Learn
To begin, alteration of our gliders should not be done without full agreement and guidance from the factory or their trained representatives. Even with such approval, be aware that the factory might not know how you will be using your equipment. Changing the pitch range of a glider is a fairly serious matter and should only be done with full understanding of all the effects.
Secondly, over-the-top lockouts are not frequent, but common enough in big-air towing that tow pilots should all have a plan to deal with them. Think about this: When we are lifted well above the tug, the tow system forces becomes similar to surface towing, with the limit of tow force only being the weak link. The susceptibility to a lockout is increased in this situation.
My experience leads me to believe that a strong thermal hitting when low can push you vertically upwards or sideways before you have time to react. If this happens when I am low, I fight it as hard as I can until I have clearance to release safely. If I am high above the tug, I stay on line with the bar pulled in as far as possible and keep myself centered if at all possible. I fully expect the tug pilot to release from his end if necessary for safety, but in the case of a malfunction, I would release before endangering the tug.
We are taught to release at the first sign of trouble, and I fully support that general policy, but in some cases, the trouble happens so fast and is so powerful that a release low would have severe consequences. In my case, I was instantly high above the tug with a strong turn tendency and a release at that point would have been ugly. The main point for us to understand is that we must gain our experience in gradually increasing challenges so we can respond correctly when faced with different emergencies. It should be made clear again that a weak link will not prevent lockouts and a hook knife is useless in such a situation, for the second you reach for it you are in a compromised attitude.
Thirdly, experienced pilots should be aware that towing only from the shoulders reduces the effective pull-in available to prevent an over-the-top lockout. Like many pilots, I prefer the freedom of towing from the shoulders, but I am aware that I must react quicker to pitch excursion. Sometimes reactions aren't quick enough and emergency procedures must be followed. It seems to me that we shouldn't be overly eager to encourage lower airtime pilots to adopt this more advanced method of aerotowing.
...in low level thermal blasts.
---
So Jim...
- Mitch Shipley
- Jim Rooney
- Steve Wendt
- Bobby Bailey
- Mark Frutiger
- Bill Moyes
- Russell Brown
- Campbell Bowen
- Paul Tjaden
- Lauren Tjaden
- Steve Kroop
- Dr. Trisa Tilletti
- Dr. Lionel D. Hewett
- Felipe Amunategui
- Bruce Weaver
- Davis Straub
- Dennis Pagen
Pioneers, designers, inventors, fucking geniuses, test pilots, tug drivers, flight park owners and operators, eminently qualified tandem instructors, regional directors, committee chairmen, crack investigators, world renowned hang gliding writers...
Every single one of them deeply concerned about this tragedy and motivated beyond any description to determine what went wrong and fix the problem to prevent it from happening again.
No fuckin' way would any of them have:
- failed to provide his take on the incident
- remained silent if he disagreed with the findings of the published report
2013/02/08 - Zack Marzec
Zack Marzec (27), an H-4 Pilot with Aero Tow and Tandem Aero Tow proficiency as well as Advanced Instructor and Tandem Instructor appointments, and a USHPA member since 2009, suffered fatal injuries when when his glider tumbled during an aero tow launch. During the launch, at an altitude of 150 AGL, the pilot encountered an invisible bullet thermal which pitched the nose up, causing the weak link to break. Upon the breakage of the weak link, the glider whip stalled and then tumbled twice. The pilot and glider's leading edge hit the ground simultaneously. The pilot was utilizing his own pro-tow style tow harness, this own high performance glider with VG on, and was not wearing a full face helmet.
- highly qualified aerotow pilot
- no inappropriate or delayed response prior to, during, or after the encounter with the invisible bullet thermal
- high performance glider
- VG on
- pro toad bridle
- state of the art release systems on both ends of the tow
- standard aerotow weak link
- glider pitched up in thermal
- pitch-up caused standard aerotow weak link to break - as it's supposed to
- upon breakage glider whipstalled, tumbled twice, crashed
- open face helmet
Zack Marzec (27), an H-4 Pilot with Aero Tow and Tandem Aero Tow proficiency as well as Advanced Instructor and Tandem Instructor appointments, and a USHPA member since 2009, suffered fatal injuries when when his glider tumbled during an aero tow launch. During the launch, at an altitude of 150 AGL, the pilot encountered an invisible bullet thermal which pitched the nose up, causing the weak link to break. Upon the breakage of the weak link, the glider whip stalled and then tumbled twice. The pilot and glider's leading edge hit the ground simultaneously. The pilot was utilizing his own pro-tow style tow harness, this own high performance glider with VG on, and was not wearing a full face helmet.
- He locked BOTH of the active discussions on this crash - and threatened to ban people.
- The usual reason... The discussions were progressing towards resolutions that would've fixed the problems for which he and his sleazy Flight Park Mafia buddies are responsible and would've revealed them all as incompetent serial killing assholes.
SkyTribe - 2013/09/11 22:00:20 UTC
What the hell is with you Michael170. You seem obsessed with accidents?
- Try swapping the period and question mark and see if those two sentences don't read a little better.
- What ACCIDENTS? This was NO WAY IN HELL an ACCIDENT. This was as much negligent homicide as the Eleni Zeri and Lenami Godinez-Avila fatalities were.
You are a very strange man.
- So you keep saying - over and over and over and over and over and over.
- Note that when Michael bumped this thing out of the Page 31 basement dust it had was packing 128 posts by 45 participants and had racked up over twelve and a half thousand hits.
- What's REALLY strange - or should be anyway is:
-- Davis locking down:
--- the most interesting, active, popular, productive, worthwhile, necessary threads
--- his forum to all but registered users
-- that carefully crafted farce of a fatality report USHGA issued
-- YOU - motherfucker
- On that last point... You are VERY OBVIOUSLY not a real person. And I know EXACTLY what you ACTUALLY are. You're an Industry plant.
Hang glider towing has, for over three decades, been a global house of cards built up on a loop of fishing line replacing a human Pilot In Command and a release that can be actuated in an emergency. And this fatality just blew up in the faces of all the Pagen/Davis/Trisa/Tjaden caliber quacks, frauds, sleazebags, and serial killers that have been running this scam.
There is NOTHING any of these motherfuckers can say about this one without revealing themselves to be the total assholes they are. So their best/only hope is to put out as much disinformation as possible and sabotage the discussions to the maximum extent possible.
Two things I'm sure of - death and taxes.
And one of the factors that goes into the first thing...
When you lose tow tension your angle of attack goes way up.
And if your angle of attack was way too high to begin with, your hang glider may not ever again be of any use to you or anyone else.
Jack Axaopoulos - 2009/07/04 12:13:01 UTC
Bullshit.
a) only the pilot can let the angle of attack increase when you lose tension. Thats 100% on the pilot. You are simply wrong and misleading again.
b) "And if your angle of attack was way too high to begin with..." Which should never be the case or youre making a pilot error. Again, you are misleading people.
This is the problem I have with you. You attempt to fallaciously attribute pilot errors to issues of mechanical towing devices or other things.
Sorry... but if you suddenly lose power, your nose just doesnt pop
Jack Axaopoulos - 2009/07/04 13:48:47 UTC
Really sick of this bombastic, grandstanding, arguing style I come to my own forum each day and get pissed off. Time to end this.
michael170, can you share any personal flying stories? What's your story?
- He spelled his name with a *"K"*.
- He is not RESTING. He is DEAD. He will not wake up, he will not be making any more totally awesome videos with spectacular flying and cute puppies, and he doesn't look like THIS:
- The reason he's currently decomposing six feet under the ground instead of shooting for cloudbase six thousand feet over it is because he was STUPID and had scores of STUPID vacuous "friends" - like you and all of your Jack Show buddies - who would rather talk about how much fun you had last weekend coring boomers and nailing spot landings than learning some of the fundamentals of aviation that Wilbur and Orville had worked out pretty thoroughly at the beginning of the previous century.
- So if you're more interested in flying stories and how many hours somebody's racked up so far this season there are plenty of existing threads you can join or you can start one of your own. But please stay the fuck out of this one so we can more efficiently cut Davis's balls off and shove them down his throat.
A PIO is a PILOT Induced Oscillation. It is an oscillation induded by the PILOT.
P.S. Did you notice how the:
- tug:
-- wasn't the least bit inconvenienced by anything that was going on behind it?
-- didn't fix whatever was going on back there by giving the glider the rope?
- Rooney Link focal point of his safe towing system didn't do shit to increase the safety of the towing operation?
- only reason this guy is still alive is because he HAPPENED to have just enough altitude to pull out?
Let me describe a similar occurance, that Davis and many others witnessed when I towed at Hay in about 2002. I was towing a Litespeed 4 behind a Dragonfly.
Shortly after launch the tug pretty much went out of sight vertically upwards, then came down again as I shot upwards - I pulled on all I could and ended up vertically above the tug with a totally slack rope. During all this I didn't feel out of control or in any risk of stalling or anything like that - just frustration at not being able to maintain position behind the tug. I tried to S turn and dive to match speed with the tug but inevitably it shock loaded and broke the weak link.
I looked at my altimeter which said eight hundred feet AGL.
I turned back to seek out the strong if turbulent lift to try to get up, and it was on the way back to the launch point anyway.
I seemed to have glided further than expected through strong sink to find the lift, and then without warning the glider pitched vertically upwards before I could react. There was a pause where I was positioned straight up looking forward at the horizon and holding the base bar thinking pulling it wasn't really getting me over the bar at all... I became aware of debris travelling up past me (the lift had contracted into a dusty and had now picked up dust that I hadn't seen on approach). Then there was lots of clatering as I tumbled.
Witnesses didn't know if it went forward of backward or how many times it rotated. When it stopped I threw my chute first and then assessed the situation. The glider picked up speed vertically downward and as I considered tying to get it to level out the chute deployed and put me down quite gently.
I dragged on the grouhd a little becuase averyone at the launch line was hanging onto their gliders as the duisty went through.
The glider had a few bent battens and one main sprog bent forty degrees, so it may not have pulled out. The chute was open about four seconds or so, an APCO Mayday 18 which it is currently popular to say is too small. It was big enough that day. I jumped in a friends harness and glider and flew to goal about half an hour later.
So turbulence can push you nose up so quickly that you can't control it, wether you are on the tow or not. Being on the tow might help, but once you exceed a certain angle of attack you lock out and diverge in pitch. The rope isn't going to pull you back down. You are going up pulling the tail of the tug up so it is going down and you can't get it back in line. I can understand how towing through dust devil could leave you pitched up and vulnerable to tumble.
Once the glider stops or goes backwards you cannot prevent a tumble, you might be lucky but you probably won't.
The Moyes Xtralite is a kingpost glider with luff lines and no outboard dive sticks (top rods). I never heard of them having any stability issues. Some other gliders at the time had quite an issue with lost stability due to sail stretch and line stretch, notably the K series from Airwave.
I've not come accross the idea of making the weak link stronger, and relying on a mouth release. You have to be sure the realease is fail safe and there is no chance of staying attached if the pilot is incapacitated in some way, such as dragging along the ground. I suppose the mouth release should work for that.
Even if we are not on tow, it is possible to fly into something that will stand your glider straight up and tail slide - if a glider tail slides it is very likely to tumble.
Zack hit the lift a few seconds after I did. He was high and to the right of the tug and was out of my mirror when the weak ling broke. The load on the tug was not excessive as with a lockout, but I was not surprised when the weak link broke. I was still in the thermal when I caught sight of Zack again. I did not see the entry to the tumble, but I did see two revolutions of a forward tumble before kicking the tug around to land. The thermal was still active in the area that I had just launched from so I did a go round and landed on a runway 90 degrees cross to the direction we were towing in.
I would be more than happy to answer any questions pertaining to what I saw and experienced, but I prefer not to engage in speculation at this point.
Paul Tjaden - 2013/02/07 23:47:58 UTC
The launch started on the main runway at the north end (2,000 feet long) and was normal until at approximately 50 feet in altitude when the tow plane hit extremely strong lift elevating it quickly and abruptly. Because of the length of the tow line, it was a few seconds later when Zach's glider entered the same strong lift and he was at an estimated 100 to 150 feet in altitude at this time.
When the lift/turbulence was encountered, the weak link on the tow line broke as the nose of the glider pitched up quickly to a very high angle of attack. Apparently, the glider stalled or possibly did a short tail slide and then stalled and then nosed down and tumbled. Eye witnesses said the glider tumbled twice and then struck the ground with the base tube low. Due to the extremely low altitude, there was no time for the pilot to deploy his reserve parachute.
Beyond these facts anything else would be pure speculation. I have personally had numerous weak link breaks on tow, both low and high, after hitting turbulence and have never felt in danger of a tumble. I have witnessed countless others have weak link breaks with no serious problems. We train aero tow pilots how to handle this situation and I am certain that Zach had also encountered this situation many times before and knew how to react properly. Apparently, Zach simply hit strong low level turbulence, probably a dust devil that could not be seen due to the lack of dust in Florida, the nose went too high and he tumbled at a very low altitude.
I wish I could shed more light on this accident but I am afraid this is all we know and probably will know.
William Olive - 2013/02/09 23:51:20 UTC
I'm making NO assumptions about the accident or its causes, because I just do not know what happened, but if we're going to discuss weak links and their relative strengths and merits we should be doing so from a factual basis.
Davis Straub - 2013/02/13 15:45:22 UTC
IMHO aerotowing is relatively safe compared with foot launching. I would certainly like to make it safer. What we would all like to know is what could we do to make it safer.
We have no agreement that a stronger weaklink would make it safer (again, I fly with a slightly stronger weaklink).
Wow...
So you know what happened then?
OMG... thank you for your expert accident analysis. You better fly down to FL and let them know. I'm sure they'll be very thankful to have such a crack expert mind on the case analyzing an accident that you know nothing about. Far better data than the people that were actually there. In short... get fucked.
Again, tell me how all this nonsense is about "safety"?
So, a stronger weaklink allows you to achieve higher AOAs... but you see high AOAs coupled with a loss of power as *the* problem? So you want something that will allow you to achieve even higher AOAs?
Are you NUTS?
I'm tired of arguing with crazy.
As I said many times... there are those that listen with the intent of responding... you unfortunately are one.
You've done a great job of convincing me never to tow you.
Thank you for that.
Mission accomplished.
Like the rest of us, you have no idea what really happened on that tow.
We probably never will know.
Jim Rooney - 2013/02/28 01:17:55 UTC
Well said Billo
I'm a bit sick of all the armchair experts telling me how my friend died.
Ah but hg'ers get so uppity when you tell them not to speculate.
...is this no brainer Zack Marzec incident such a big inexplicable fucking mystery? Could it possibly be because it was precipitated by a Rooney Link and the front end / commercial operator sleazebags controlling these discussions are desperately trying to make it a big inexplicable fucking mystery to preserve their paper thin veneers of competence and shield themselves from accountability?
Take the time to put your hand on your deployment handle from time to time, and do a practice deployment hanging in your harness. This might mean you can deploy a chute remarkably low. Its been done before.
This is total fucking bullshit.
- The chances that someone's ever gonna be done in a tow situation at a halfway competently run operation are worse than getting hit by an asteroid. It's never happened - and won't.
- People in Bob Buxton and Mike Haas aren't even capable of letting go of the basetube with one hand to blow a release "within easy reach" without making the situation worse - even when the inevitable consequences of keeping both hands engaged in fighting for control will be severe brain damage or instant death.
- And when you get released from tow you've got a good idea what's gonna be happening in the immediate future. That's far from the case when a decision to toss a chute is made.
- It's ten thousand times easier to avoid getting into critical situations on tow...
-- competent pilots
-- runway streamers
-- launch dollies
-- two point bridles
-- one and a half G weak links
-- releases that don't stink on ice
...than it is to get out of them using parachutes.
- And you can't cite - from anywhere in the entire history of hang glider towing - any examples from a halfway competently run tow operation in which a parachute was or could have been of any possible use.
I wrote the piece very soon after the incident (Davis will witness that)...
Is that the most trustworthy source you can cite?
...so the altitude numbers must be right. Over the years I had come to think I was higher. I'm a bit shocked now read how low the deployment altitude must have been... how lucky I was!
Good thing it didn't happen at one fifty, huh? We can't afford to get into situations in which our survival is dependent upon luck. Luck is winning a round of Russian roulette with five bullets in the cylinder.
It does seem that drier air is likely to have more shear and the thermals have sharper edges and are more "tippy". You don't seem to get dusties with high humidity - its not lack of dust its the viscosity of the air I think.
Bullshit. Humid air is lighter/thinner air. Upping the humidity has exactly the same effect on the glider as upping the altitude.
The reasons you get better soaring / more dangerous flying conditions with dry air:
- more:
-- overnight heat radiation back into space
-- daytime surface heating
- higher:
-- lapse rates
-- cloudbases
For the record, having attended big towing comps and big mountain comps... Crashes while launching are the same frequency in both, if anything a little more common on mountains.
What percentage of the tow launch crashes you're seeing are NOT...
Pilots 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.
Hahahahahahahahaha
Oh that's just rich!
Riiiiiight... it's my attention span at issue here....
and I'm the one that's arrogant!
HAHAHAHAHAHAHAAHAHA
No, I'm not being nice. No, I do not feel the need to be nice. You're trying to convince people to be less safe. I don't want to be on the other end of the rope when someone listening to this drivel smashes in.
I've heard it a million times before from comp pilots insisting on towing with even doubled up weaklinks (some want no weaklink). I tell them the same thing I'm telling you... suck it up. You're not the only one on the line. I didn't ask to be a test pilot. I can live with your inconvenience.
Please tell me again what's wrong with the wheel? Why you keep trying to reinvent it?
Yes, please fall back on the "I'm just saying they could be stronger" bull when you've made it quite clear that anything lower than cable (1200lb) is acceptable.
The simple fact is that you're not improving the system.
You're trying to make it more convenient and trying to convince yourself that you should be towing with a stronger weaklink.
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).
Then again, Russell Brown had us double up behind him after six breaks in a row at Zapata. We couldn't figure out why we had so many breaks so quickly. Maybe just coincidence.
I am more than happy to have a stronger weaklink and often fly with the string used for weaklinks used at Wallaby Ranch for tandem flights (orange string - 200 lbs). We used these with Russell Brown's (tug owner and pilot) approval at Zapata after we kept breaking weaklink in light conditions in morning flights.
I took the opportunity to get Betinho's and Ollie's computers operating on the Internet. In return I got some copies of a few of the photos that Ollie took last year at Hay. Ollie hadn't made an electronic version of his most famous photo though.
This is a classic shot of a pilot flat on the ground (he was unconscious for a few seconds). He had just come off the dolly and broken a weaklink. The glider is nose down on top of the pilot with its nose planted on the pilot's helmet. On the top of the glider it states next to a large line drawing of Albert Einstein with his tongue out: "Are you going Litespeed?" The obvious retort was, "Who's going Litespeed, now?" Ollie was strongly discouraged from ever publishing this photo, for obvious reasons.
Davis Straub - 2008/04/22 14:47:00 UTC
Pilots 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.
The link will take you to a website that is mostly the raintings by a couple of outspoken, ill-manndered individuals who denounce everyone else as idiots.
For example: "Most folk who fly hang gliders are idiots who have no business modifying critical systems they don't have a snowball's chance in hell of understanding." A typical post by one of those individuals.
Validated by Zack Marzec, Mark Frutiger, and the other good folk at Quest on 2013/02/02.
Dennis Wood - 2012/08/13 17:54:59 UTC
Suffolk, Virginia
...to 154. You're good. The cool thing about 130 pound Greenspot is that no matter what strength you're told is ideal for you and your glider, within a range between 100 and 360 pounds...
I'm thinking about doing a bit more testing as there seemed to be some disagreement around here about what the average breaking strength of a loop of Greenspot (or orange) weaklink was.
...you can find some aerotow professional who will give it to you.
Davis Straub - 2012/08/13 18:08:42 UTC
Used to do 130 lbs. Now do 200 lbs.
Yeah, but...
Davis Straub - 2013/03/06 18:29:05 UTC
You know, after all this discussion I'm now convinced that it is a very good idea to treat the weaklink as a release, that that is exactly what we do when we have a weaklink on one side of a pro tow bridle. That that is exactly what has happened to me in a number of situations and that the whole business about a weaklink only for the glider not breaking isn't really the case nor a good idea for hang gliding.
I'm happy to have a relatively weak weaklink, and have never had a serious problem with the Greenspot 130, just an inconvenience now and then.
A weak link connects the V-pull to the release, providing a safe limit on the tow force. If you fail to maintain the correct tow position (centered, with the wheels of the tug on the horizon), the weak link will break before you can get into too much trouble.
...Allen? Maybe if you and a few dozen of your smartass buddies had figured out what was going on and done something of substance at that point that stupid little kid wouldn't have ended up splattered all over the runway less than six months later.
Paul Hurless - 2012/08/14 07:26:51 UTC
About the above posted link, over there it would seem that even though a certain volatile individual was banned from the .org, he still reads it as a visitor. I guess he can't live without us. His latest rants are very amusing.
Stay tuned, asshole. This Certain Volatile Individual's rants are getting more and more amusing all the time.
