Weak links

[Tad Eareckson]

http://www.wibw.com/content/news/Rossville-man-dies-in-hang-gliding-accident-400295171.html
Rossville man dies in hang gliding accident

Natalie Dattilio 2016/11/07 14:06 CST
Updated: 14:16 CST

TOPEKA, Kan. (WIBW) - A Rossville man has died in a hang gliding accident.
On November 5th at approximately 3:30 p.m., Shawnee County Sheriff's Office deputies responded to the 3700 block of NW Davis Road for a report of a hang gliding accident.
When officers arrived they found an unresponsive man lying in a field, wearing a harness attached to a hang glider.
Officers attempted CPR but the individual died of his injuries.
He was identified as 50-year-old Jeffrey L. Glidewell.
The Sheriff's Offices says the incident is still under investigation.

Jeff Glidewell - 25340 - H4 - 1981/03/01 - T. Dolsky - FL AWCL CL TUR - Exp: 2011/01/31

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

Jay Glidewell - 2016/11/09 19:56:13 UTC
Topeka
2016/11/09 - Joined

Jeff Glidewell crash witness

My Name is Jay Glidewell and I was with him at the time, I've had a private piolit lic since 93 so I have some knowledge of flight myself but never hang glided. After thinking about it a little more here is what happened. Jeff had been working on a tow winch for several years by making a double rim wheel to put on his corvair for use as a reel. (stationary with the wheels jacked up) He had 5000' of rope on the spool and had it stretched out to the launch site. I was at the launch site talking to the guy in the car. The wind got right and he went, It was perfect how he went up. He went out about 1/2 mile and was up about 120' approx. He released from the tow line and it shot out and the parachute came out attached to the tow line, There was no "lockout" the tow was 110% perfect. As soon as he released he went into a left turn steepening up to maybe 45 degrees, He came out of the turn at about 180 degrees and went into a dive into the ground. From release to impact seemed like maybe 2 seconds. The way the cord shot out on release tells me that he drastically slowed, stalled out and started to spin Brought it right out of the spin and got the nose down just like you should but wasn't quite able get the nose up in time to avoid the ground, The wind was fairly light and may have been 5-10mph. If he would have dropped the nose and got enough speed up to take the pressure off the rope before release he would be here now telling everyone all about it. It was much like running with a kite string then suddenly letting go. He didn't suffer and he could never have been happier that this thing worked so well. I have the flight but not the crash on video and right before he released I said "man, I might have to try that." There will be a meet and greet thing at Rossville city park Sun 11-13-16 1-3pm for anyone that wants to come.

Manned Kiting
The Basic Handbook of Tow Launched Hang Gliding
Daniel F. Poynter
1974

"The greatest dangers are a rope break or a premature release." - Richard Johnson

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"...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links

Jim Rooney - 2007/08/01 19:49:30 UTC

It's more of this crappy argument that being on tow is somehow safer than being off tow.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?

Jim Rooney - 2011/08/26 02:44:10 UTC

The "purpose" of a weaklink is to increase the safety of the towing operation. PERIOD.

Probably using one of those Tad-O-Links that allows the glider to climb too steeply.

P.S. Thanks, Jonathan.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

David Botos (dbotos) - 2016/11/09 21:28:25 UTC
Southwest Virginia

Jay - sorry to hear about Jeff. Have you or anyone else submitted an accident report to USHPA? Sharing the details of the accident as you have done here could help save another pilot.

And that's u$hPa's primary mission: compile and freely distribute all possible relevant details of incident reports - especially fatalities in which the pilot suffers fatal injuries - and identify the critical issues in order to make the sport as safe as possible for all participants.

It sounds like the pitch of the glider at release may have been a major factor. My hypothesis is this: upon release, tow line tension...

PRESSURE - asshole. Didn't you bother to read his post?

...on glider/pilot (forward and slightly down) goes away. Now, without the forward component of tow line tension, the only fore/aft force on the glider is drag, which comes on suddenly (due the nature of releasing a tow line). The sudden drop in airspeed combined with a high pitch angle could easily lead to a stall.

Which, in hang glider towing, is referred to as a totally benign inconvenience which increases the safety of the towing operation.

Your description of the left turn after release (assuming the 45 degrees mentioned is bank angle), suggests that the left wing may have stalled first and caused the turn/dive.

Asymmetrical inconvenience. Make sure you get proper training to learn how to deal with it.

Does anybody remember when Robert V. Wills was the national organization's Accident Review Committee Chairman and the way he'd compile and publish every scrap of info on every crash that made the news from anywhere around the planet that he could get his hands on? And now a solid pilot eyewitness (probable brother of the victim) of a fatal crash gets posted on the most mainstream glider forum on the planet and nobody from u$hPa will touch it. Instead Jay's supposed to send u$hPa a copy so Tim Herr can read and immediately shred it.

Jay Glidewell - 2016/11/09 22:08:52 UTC

I don't know how to report it...

You already have.

It is the same glider and yes he had a weak link, Three or six strands of string line he said tested out to like 225#.

See?

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks

Jim Rooney - 2013/03/05 21:40:02 UTC

You want MORE.
I want you to have less.
This is the fundamental disagreement.
You're afraid of breaking off with a high AOA? Good... tow with a WEAKER weaklink... you won't be able to achieve a high AOA. Problem solved.

I'm sorry that you don't like that the tug pilot has the last word... but tough titties.
Don't like it?
Don't ask me to tow you.

Go troll somewhere else buddy.
I'm over this.

Tad-O-Link.

They were not broke. Like i said everything looked great up to and including the release seemed perfect to me the 2 quick release buckles had been released by him also. The other release was two small straps that one had a safety pin looking kind of thing that went in a little tube connected to a rope he pulled to release it..

Well, whatever it was it sounds like it worked great. Obviously nothing homemade with a short track record.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34646
Are you satisfied with flex wing handling qualities?

Ryan Voight - 2016/08/22 20:14:50 UTC

The reason this is a trick question, is the same reason it should be irrelevant that the Lookout release has less mechanical advantage, and may be difficult to use during the high tension of a lock-out. There are other releases (no so common anymore, thankfully) that could become full-on inoperable when the tension increased...

So... are you willing and able to manually release when you believe you are entering an unrecoverable lockout? Hint- if you are *entering* an unrecoverable lockout... you should have already A) steered yourself back where you belong, and if you were unable to do A then do B) release before before BEFORE entering an unrecoverable lockout situation.

Failing to fly the glider where you want it to fly is a serious situation... a lockout is an even more serious situation, but it is a symptom that follows that first problem. Failing to recognize the first problem, and remedy or escape *BEFORE* the following lockout ensues... THAT is what people seem not to get here.

Davis wrote pretty extensively about this when the comp-fatality happened, and even shared how the comp rules were written to ENCOURAGE "when in doubt, just get out". Frankly, a lockout should never happen... it's not a single failure, and it's not a problem with the equipment or with the mechanics or physics of what is being attempted... a lockout can only happen as the result of operator error(S)... plural...

Here we have a good account of a Hang Four surface tow fatality from a pilot eyewitness with a video of everything prior to impact.

His observation, logical and disputed by NO ONE, is that upon release from a "110% perfect" tow in totally benign conditions the glider entered a fatal inconvenience stall simply because the pilot didn't pull in before releasing - a control pretty much off the table with a release that...

53-35610
http://c2.staticflickr.com/6/5606/30403885096_339d71016d_o.png


...stinks on ice.

But according to Ryan Instant-Hands-Free-Release Voight one should be able to blow his easily reachable release in any situation that befalls anyone with enough brains to abort before the glider progresses to an eighty degree roll and whatever equipment one is using - save for Rube Goldberg crap from T** at K*** S****** - will be perfectly fine.

13-22509
http://c1.staticflickr.com/9/8152/29072298334_eb6b25ae20_o.png

15-22604
http://c1.staticflickr.com/9/8039/29072297944_47720ef003_o.png

17-22705
http://c1.staticflickr.com/9/8245/29072297624_4ea198fc0f_o.png

22-22806
http://c1.staticflickr.com/9/8480/29074013803_7b589eb0cd_o.png

27-23302
http://c1.staticflickr.com/9/8109/29074011143_b58df36d10_o.png


Ryan and his Industry dickhead buddies are further majorly screwed by this one.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

Dave Gills - 2016/11/10 01:13:09 UTC

Over the top, thermal induced, lockout?
If so, these things require a VERY fast release.

How fast? What's a good reaction time to blow tow when one's standing on one's tail?

One such as this recently killed an exceptionally skilled...

And terminally stupid.

...pilot.

Cool dude pro toad dope on a rope. His standard aerotow weak link didn't break quickly enough.

Sad news

Oh well. More inconvenience truth about the actual physics of glider towing thrown into everybody's faces.

Jay Glidewell - 2016/11/10 01:20:05 UTC

No lockout, Tow was100% perfect...

- Like your writing.
- Oops. We seem to have slipped ten percent since two Jay posts ago.

...including release, When the cord released he lost his forward momentum and stalled , Not quit enough room for a recovery I guess.

- Nope. Almost, but not quit.
- Then it should be kinda hard to make the case that the release was 100 to 110 percent perfect, shouldn't it?

...It was just like running with a kite on a string in low wind then stopping.

Instant total loss of thrust a BAD thing? Are you SERIOUS?

David Botos - 2016/11/10 12:12:10 UTC

This safety notice mentions the same phenomenon with tandem aerotowing:

Yeah, it's very specific to TANDEM aerotowing. The physics, aerodynamics involved are totally different when you've got a student under the wing and along for the ride.

If the pilot of the tandem glider finds that he/she is too low behind the tug and slow enough that the glider will not climb without pushing out past trim, then the pilot should pull in and release rather than trying to push out and climb to the tug altitude. Though pushing out to climb to the tug altitude has been a common practice usually accomplished without incident, there is a deep underlying danger in 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 ft.) The most extreme cases may result in structural failure of the glider.

http://www.ushpa.org/page/hg-tandem-aerotow-operations

If the pilot of the tandem glider finds that he/she is too low behind the tug and slow enough that the glider will not climb without pushing out past trim...

- Who's the pilot of the tandem glider? Can he/she be the designated Pilot In Command if he/she's the student?

- Seems to me that whenever there's a fatal tandem crash - Bo Hagewood / Michael Elliot, Bill Bennett / Mike Del Signore, Arlan Birkett / Jeremiah Thompson - u$hPa and its Operatives always bend over backwards to assign responsibility to the individual with the mostly empty card. Fuckin' AMAZING that they didn't try to dump the 2015/03/27 on...



...Kelly's tandem student. Maybe sue his family out of existence.

- If you have an instructor and a STUDENT on a fucking tandem flight - which, by definition, is the only combination legally possible - shouldn't it be fucking obvious to BOTH parties when their plane is being dangerously compromised?

...then the pilot should pull in and release rather than trying to push out and climb to the tug altitude.

- I guess not. The assholes you're certifying to be top notch flight instructors are all too fuckin' clueless to have an awareness that their aircraft is one magic fishing line pop away from unimaginable disaster.

- What's the fuckin' tug pilot - the guy Jim Keen-Intellect Rooney, the best of the best of your certified drivers, assures us is the legal Pilot In Command of BOTH aircraft - supposed to be doing while the tandem's wallowing around low on the back end of his rope? Nothing, I guess. 'Cause we only want the dead guys to have been responsible for the factors contributing to the crash.

Though pushing out to climb to the tug altitude has been a common practice usually accomplished without incident...

Like making easy reaches to Industry Standard releases and running off ramps after confirmation of hook-in status via a hang check in the set-up area five minutes ago.

...there is a deep underlying danger in doing this. Should the tandem glider become unattached from the tug during this maneuver...

What are the odds of THAT happening with a tandem glider wallowing low behind a tug? It just BECOMES UNATTACHED for no reason whatsoever? Somebody quote me anybody from the entire history of hang glider towing a driver, glider pilot, observer reporting that a glider "BECAME UNATTACHED" from a tow.

...the nose high attitude of the tandem glider attained while doing this will cause a very abrupt stall which will result in a...

...severe inconvenience.

...much greater altitude loss than one would expect (possibly more than 750 ft.)

- Whoa! No fuckin' way would one expect a much greater altitude loss than one would expect!
- How 'bout a solo pro toad tumble from 150 feet? Would that be an option?

The most extreme cases may result in structural failure of the glider.

Suck my dick. Nobody's EVER lost 750 feet and/or broken a glider prior to impact in any towing incident.

So how come you posted this? There's not a word in what you quoted of the advisory that indicates any relevant issues for SOLO gliders. And this topic concerns a SOLO tow fatality.

Bill Jennings - 2016/11/10 12:41:32 UTC
Chattanooga

Is this a situation that puts more stress...

Pressure.

...on the weak link...

Focal point of one's safe towing system.

...when the glider is low on the tug and pushing out aggressively to try to climb back to the tug?

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"...

IOW, a time when a weak link break...

An increase in the safety of the towing operation. Period.

...is more likely?

- I dunno... Try asking Bill Bennett / Mike Del Signore, William Woloshyniuk / Victor Cox, Arlan Birkett / Jeremiah Thompson.

- Who gives a flying fuck? It's a mere inconvenience at worst - by definition.

- How 'bout the...

http://ozreport.com/5.126
Flytec Dragonfly

USAFlytec - 2001/07/14

Steve Kroop - Russell Brown - Bob Lane - Jim Prahl - Campbell Bowen

The tail section of the Dragonfly is designed so that it can accept in-line as well as lateral loads. Furthermore the mast extension, which is part of the tow system, is designed to break away in the event of excessive in-line or lateral loads. The force required to cause a breakaway is roughly equivalent to the force required to break the double weaklink used on the tail bridle. More simply put, the mast would break away long before any structural damage to the aircraft would occur.

http://groups.yahoo.com/group/skysailingtowing/message/4633
Weaklinks and aerotowing (ONLY)

Steve Kroop - 2005/02/10 04:50:59 UTC

To: Davis Straub; Tow Group
Cc: Rohan Holtkamp; Paris Williams

Davis,

Your weak link comments are dead on. I have been reading the weak link discussion in the OR 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.

You are completely correct about weak links and lockouts. If I can beat the horse a little more: Weak links are there to protect the equipment not the glider pilot. Anyone who believes otherwise is setting them selves up for disaster. The pilot activating his or her releases is their way to save themselves. A perfect analogy is the circuit breaker in your home, it is there to protect the wire not what you plug into the wall socket. If anyone does not believe me they can plug their car retrieve 2-way radio into the wall socket and watch it go up in flames with the circuit breaker cumfortably remaining in the on position (I hope no one really tries this .

A discussion of the strength of weak links is incomplete without a discussion of the tow bridal. I hear (read) strengths quoted with respect to the combined pilot and glider weight yet this is meaningless info with out knowing what bridal configuration is used and where it is placed in the bridal system. For example, a 200# weak link can allow between 200# and 800# of towline force depending on where it is placed within the various popular bridal configurations.

On the tow plane we use 1-1/2 loops (3 strands) of 130# line. The weak link is placed in the top of a V-bridal which would yield a maximum nominal towline tension of around 780#. However, due to the fact the knots (two are required since there are three strands) are not "buried" the maximum towline tension is greatly reduced. I do not know the exact tow line tension required to break this weak link but the value is somewhat moot since the weak link is not too strong so as to cause any damage to the tow plane and it is not too weak to leave the glider pilot with the towline.

Summary

Do not attempt to aerotow unless you have received proper training
Do not attend an aerotow comp if you do not have considerable experience flying a comp class glider in comp class conditions
Weak links are there to protect the equipment
Weak links do NOT prevent lockouts and no amount of weak link rules will prevent lock outs
In the event of a lock out releases are there to save the pilot

Best regards, Steve - Flytec USA

...Dragonfly tow mast breakaway protector? 'Specially now that weak link strengths and descriptions are heavily guarded Industry secrets?

And still no words of wisdom from the likes of either Ryan Instant-Hands-Free-Release Voight or Jim Keen-Intellect Rooney. Both smart enough to shut the fuck up regarding incidents that can't be shoehorned into u$hPa/Industry towing theory.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

Tom Lyon - 2016/11/10 15:59:01 UTC

Thank you for your explanation, Jay. With surface towing, the very steep attitude of the glider transitions virtually instantly to a steep angle of attack and loss of speed upon release of the line supplying the power.

- Got news for ya, idiot. A pound of aero tension translates to a steeper attitude than a pound of surface tension - once one's measurably off the ground.

- Bullshit.

http://www.hanggliding.org/viewtopic.php?t=11497
Aerotow release options?

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

My second sentence describes what im trying to say better.

Agree on the power versus non-power. Just never had an issue cuz I know how to fly a glider. If you dont instinctively know how to set your proper angle of attack in any given scenario, you shouldnt even be flying. Any sudden loss of bar pressure should trigger a response from the pilot.

What I was trying to address is AT's original quote:

There IS NO SUCH THING as "the limit for safe operation" with respect to tow line tension 'cause you can get killed BECAUSE you have ZERO tension

Its nonsense and more grandstanding. You can get killed BECAUSE you ran out of gas in your car. You can get killed BECAUSE you stop pedaling your bicycle.

Guess what, I can fly a glider all over the sky with a towline attached to the nose and nothing on the other end, and guess what??? It still flies! WOW!

Really sick of this bombastic, grandstanding, arguing style I come to my own forum each day and get pissed off. Time to end this.

It appears to me that this is what you are describing.

Manned Kiting
The Basic Handbook of Tow Launched Hang Gliding
Daniel F. Poynter
1974

"The greatest dangers are a rope break or a premature release." - Richard Johnson

We're all so terribly sorry for your loss.

And we're obviously speaking on behalf of us all and will all take steps to minimize the possibility of anything like this ever happening again.

Continuing deafening silence from Ryan Instant-Hands-Free-Release Voight.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

Dave Gills - 2016/11/10 01:13:09 UTC

Over the top, thermal induced, lockout?
One such as this recently killed an exceptionally skilled pilot.

http://ozreport.com/forum/viewtopic.php?t=30971
Zach Marzec

William Olive - 2013/02/27 20:55:06 UTC

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.

http://ozreport.com/forum/viewtopic.php?t=31052
Poll on weaklinks

Jim Rooney - 2013/03/05 19:42:58 UTC

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.

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.

Note the complete and totally deafening absence of dissent in response to Dave's statement of simple and blindingly obvious fact regarding the Zack Marzec fatality. (Also note that there is no other incident with which that one can be confused by any stretch of any imagination.

Nobody's selling the inconvenience snake oil any more. An ill timed increase in the safety of the towing operation can be deadly no matter who the fuck it was who was on tow a millisecond ago. And the reputations of all the salesmen are TOAST - irrevocably. Major historical shift.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

Jim Gaar - 2016/11/09 21:38:42 UTC

Thanks Jay. Sorry to hear about Jeff. I met him years ago at small airport NW of Lake Pamona. Nice guy. I believe he was flying a Pliable Moose then with "Easy Rider" on the wings.

Hay, what kind of wing was he flying? Do you know what kind of release he used?

Something within extremely easy reach.

Do you know if he was using a weaklink?

- Undoubtedly the one with the best known and accountable safety record (in my personal books anyway).
- Why are you asking? What possible relevance could it have had with respect to this incident?

I'm sure the pilots here...

In Jack's Living Room - and not on any other forum.

...would like to know as much as we can so that we can remain safe.

So that you can REMAIN safe? If you're all already safe - and you all so very obviously ARE - why do you need to know anything about this crash?

It sounds like Jeff would be the kind of guy that would be happy to share.

And we had so much sharing from him BEFORE the fatal crash.

Again, sorry for your loss.

Chin up, good man.

Sam Kellner - 2016/11/10 14:45:27 UTC

Re: Jeff Glidewell crash witness

My Name is Jay Glidewell He went out about 1/2 mile and was up about 120' approx. .

Hello Jay, So sorry for the loss of your bro.

How do you know it was his bro?

Thanks for posting here.

Where so many others can't - and those who can are under constant threat of having their topics locked down and posts deleted if Jack doesn't find them suitable for his Living Room.

It could help many of us.

http://farm9.staticflickr.com/8143/7462005802_bbc0ac66ac_o.jpg

I never met Jeff but remember the name.

The quote/ portion of your report that don't add up to me.???

I didn't think his name was really Jay Glidewell either.

Usually, being 1/2mi out, the glider is well above 120'.

Yeah, usually when the glider's a half mile out from a stationary winch the glider's MUCH higher.

Can you describe how the tow line was attached to the glider?

http://www.ushawks.org/forum/viewtopic.php?f=17&t=1081
Platform towing /risk mitigation / accident

Sam Kellner - 2012/07/03 02:25:58 UTC

No, you don't get an accident report.

Was it attached only to the pilot?
Was it attached to the pilot and to the keel of the glider?
RIP Jeff.

Thanks again.
Sam

Suck my dick, Sam.

2016/11/10 15:10:30 UTC - 3 thumbs up - Jim Gaar

Figures.

Jim Gaar - 2016/11/10 15:09:49 UTC

In this accident the pilot was towing behind a static wench, as described by Jay to be a home made spool attached to the drive wheel of a car on a jack stand. I assume there were no tension devices or pressure gauges.

Gotta make sure the tensions and pressures are right...

029-04917
http://farm4.staticflickr.com/3735/13746338404_0b90a8007d_o.png


...for a really safe tow.

This is a whole 'nuther ball game in the towing world. Let's not compare apples to bowling balls.

The wing was a Pliable Moose. It's at least a 30 year old wing. I think it's even cantilevered. I can't find a picture of one. Ken?

There was 5000 feet of towline. How many feet were on the ground at the beginning of the tow? What was this towline made of?

Something nice and stretchy to help keep the tension constant.

Is this picture getting clearer for you all?

Jay it sure would be good to see the launch video.

flakey - 2016/11/10 15:42:51 UTC
Huntington Beach

Sorry for your loss

40 year old modified standard wing.

I'm guessing nothing to write home about with respect to energy retention.

David Botos - 2016/11/10 17:56:03 UTC

Aerotow and surface tow are no doubt different animals, each with some of their own unique characteristics...

Yeah, a Tad-O-Link won't kill a surface driver. Absolutely deadly to Dragonfly drivers however - if it's on a SOLO glider. It pretty much guarantees that the front end release will be rendered inoperable and the tug will be stalled if he tow's straight or have it's tail pulled around out of control when the glider's flying away from the tow with its pilot trying to fix a bad thing instead of actuating his easily reachable bent pin pro toad release.

...but the phenomenon of suddenly going from towed flight to free flight at a pitch attitude that causes a stall in free flight seems largely the same.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?

Jim Rooney - 2011/08/28 10:15:12 UTC

Oh, in case it's not obvious (which it doesn't seem to be), once someone starts telling me what the "sole" purpose of a weaklink is, I tune them out as they have no clue what they're talking about.

Weaklinks are there to improve the safety of the towing operation, as I've stated before.

Any time someone starts in on this "sole purpose" bullshit, it's cuz they're arguing for stronger weaklinks cuz they're breaking them and are irritated by the inconvenience. I've heard it a million times and it's a load of shit. After they've formed their opinion, then they go in search of arguments that support their opinion.

Jim Gaar - 2016/11/10 18:15:19 UTC

Not when the wing is a cantilevered 30+ year old hang glider on a static wench with no pressure or tension gauges and inexperienced "wench" operators.

I love that we can all go fly as we wish here in the US. I just wish Jeff had reached out to some one with more experience so that he could be doing what he wants and still have a beer with his brother after he's done.

Like Sam Kellner, Quest, Lookout, US Hang Gliding, Inc., Mission Soaring Center, Davis's Risk Mitigation Committee, Peter Birren, Steve Exceptionally-Knowledgeable Wendt, Dr. Trisa Tilletti... Lotsa these fine operations and individuals who are always weighing in after all these tragedies and setting everybody straight on things.

Brian Scharp - 2016/11/10 18:35:26 UTC

http://en.mimi.hu/aviation/cantilever.html

Jay Glidewell - 2016/11/10 18:38:36 UTC

only the pilot, up by his shoulders and then under the bar and attached to his crotch area. He was talking about how you undo one first then the other because of how it changed your pitch or angle of the line or something.

Good thing he wasn't using one of those Koch two stage chest crusher jobs. He could have had his chest crushed.

He was certified in it...

Really?

Jeff Glidewell - 25340 - H4 - 1981/03/01 - T. Dolsky - FL AWCL CL TUR

By whom?

...and apparently was well acquainted with the methods.

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?

Jim Rooney - 2011/08/24 16:26:09 UTC

Welcome to towing.
We've been doing this a long time and are quite familiar and comfortable with our processes.

http://4.bp.blogspot.com/-bRrpHNa68iY/UQ6Pv9gRZyI/AAAAAAAAjTg/Hc22bx5122Q/s2048/20943781_BG1.jpg

He had a pull string release that was out 4 or 5 feet then also the two quick release points mentioned earlier. Seemed to unhook great.

Yep, just as effectively as a standard aerotow weak link.

Both latches open quick release out front had worked and the break point strings looked great.

Not seeing any problems then. Can we talk about something else now?

Dave Pendzick - 2016/11/10 18:43:11 UTC

So the tow line was not attached to the glider in any way, only to the pilot & in two locations? I am not familiar with that method.

The glider's NEVER connected in surface tow operations - save for skimming training stuff.

Jay Glidewell - 2016/11/10 18:48:51 UTC

He had a scale on some pulleys to tell what to hold it at. I think there was a camera on that too and I will try to get a copy of that. He had some white rope and some yellow, Braided and made the loops by taking the ends and sticking them back up the middle of the rope a foot or more to hold them...

Almost certainly polypro.

He had out about 4400 feet of line I think. He was getting all this from somewhere he wasn't just dreaming it up.

Sounds like heavy Hewett influence.

I'll try to get the video's on here where they can be seen. Like I said, I don't have the release or crash but that might be good because I sure didn't need to see that twice.

If we'd had a video of Zack Marzec buying the farm at the conclusion of his inconvenience whipstall and tumble our job would've been a thousand times easier.

Jay Glidewell - 2016/11/10 18:51:21 UTC

It's a 16 min video and at the rate it's downloading it will probably be tomorrow before I can put it out.

Well, tomorrow's come and gone.

Jay Glidewell - 2016/11/10 19:03:25 UTC

Yes Dave, Correct

How's it feel to be right about something, Dave?

David Botos - 2016/11/10 22:08:21 UTC

I don't know the flying characteristics of the older glider to be able to comment on that in relation to more modern gliders.

Crap performance / energy retention. That was a major factor here.

My point was that when releasing from tow (be it aerotow or surface tow) at a pitch angle that would cause a stall in free flight, the sudden onset of drag (since the tow line force is no longer there to counteract it) and the subsequent reduction in airspeed and resulting stall would be largely the same.

Well yeah, but that's totally different from the effect of a weak link always breaking at the worst possible time, when the glider is climbing hard in a near stall situation. That's just an ARGUMENT Donnell has heard and a weak link break always increases the safety of the towing operation - PERIOD. Otherwise you're just making more of this crappy argument that being on tow is somehow safer than being off tow.

One difference with surface towing, you have some downward component to the tow line tension that goes away upon release, changing the effective wing loading (which was artificially high when the downward component of tow line tension was present).

So what? No aircraft ever got in trouble for dumping ballast - 'cept for losing capability to penetrate out from a ridge in a strong headwind, which isn't a relevant issue here.

But, that is a bit apples-to-oranges since one is a wing loading in towed flight and the other is a wing loading in free flight.

It's a total nonissue. Down vector is just the inevitable waste of towline tension one must accept with surface towing.

I think the big take away here is that while towing, you need to fly in such a way that you would keep flying in free flight, whether that transition to free flight happens expectedly (normal release) or unexpectedly (emergency release, weak link breakage).

Everybody knows that...

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question

Jim Rooney - 2008/11/22 22:31:35 UTC

Nail on the head Brian!

The simple fact is this. The only reason anyone even gives Tad the time of day is that they want to believe him. Why? Because they don't like to be inconvenienced by a weaklink break. That's it.

Sure, everyone digs around for other reasons to believe, but at the heart of it, it's convenience.
No one is actually scared to fly with a standard weaklink. They may say they are, but deep down inside, they're not.

Tad loves to speak of himself as a scientifically minded person. Yet he ignores a data pool that is at minimum three orders of magnitude higher than his. It is thus that I ignore him.

INSTINCTIVELY.

Jay Glidewell - 2016/11/10 22:34:53 UTC

Yes, That was mine too, Maybe he was being towed kind of on the slow side since it was the first time with this tow set up.

The more slowly he was being towed the less consequence coming off tow would've had.

At least be ready to yank that bar back if you get a break...

EVERYBODY's *READY* to yank the bar back. This asshole:

06-03114
http://farm4.staticflickr.com/3728/9655895292_f4f808fb0e_o.png


already has the bar yanked back almost as far back as possible just coming off the cart. Problem is that's not always gonna be enough to do the job. Not every abrupt and total loss of thrust is survivable for an aircraft of any flavor in all circumstances.

And the thought now occurs to me that this was quite likely a foot launch. (A launch cart isn't a factor in a safe towing system under the Twelve Steps of Donnell's Skyting Criteria.) So one must wonder if Jeff was still flying from the control tubes. I doubt it but one must also wonder why he elected to release at 120 feet with 4400 feet of line still out in brain dead conditions with everything going great.

...and if releasing, Build up your speed and take the tension off the rope before releasing.

Dennis Pagen - 2005/01

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 20-degree bank--so I quickly released before the lockout to the side progressed. The glider instantly whipped to the side in a wingover maneuver.

[Tad Eareckson]

http://ozreport.com/20.226
The accident report on the flying with the dolly

Davis Straub - 2016/11/10 22:45:35 UTC

At Cowboy Up

http://ozreport.com/docs/Launchdolly.pdf

Richard Thorp

Launch Dolly Caught on Harness Zipper Line and Taken Aloft
Wharton, Texas Sunday 30 October 2016

First:
Get a hook knife if you do not have one!
Check for loose lines before launch
if you are flying and climbing, continue - it gives thinking time and if needed, parachute opening time.

Following is a summary of the incident last Sunday where a launch dolly caught my Wills Wing Z5 harness and was taken aloft. No injuries - in no small part to the fantastic flying of Tiki who saw the situation and carefully pulled me to a safe height where I could deal with it.



Pilot Narrative:

After a normal ground run, into a slightly crossing wind, I felt some significant bumps on the boot of the harness as the glider left the dolly - and something significant tugging at me. The glider remained under control, although at this stage there was clearly something strange - it felt exactly as it was, a weight that would swing like a pendulum a few seconds after a weight shift was applied. At 50 - 100ft I looked down and saw the dolly hanging below me from the boot of the harness, hanging from the zipper line. Given that the glider was flying, I had reasonable control over it, and we were climbing I simply focused on following the tug. Luckily the air was fairly smooth - and provided I was not too aggressive with the weight shift the main effect of the dangling dolly was to apply a delayed yaw to my harness - the process was: weight shift - glider responds, relax to stop the delayed swing of the dolly shifting my CG and just let it rotate my body about the hang strap. It got a little more complicated if I needed multiple inputs and rough air would have been a big problem. I was also concerned not to break the weak link, I really wanted some height, so the focus was to just climb with the tug with as little drama as possible.

I could see the dolly was hanging by the zipper cord just caught round one of the small bolts that protrude from the bottom of the side rail - and a little concerned that it would fall on something / someone - as well as hoping that it would just fall ...

Once above 2000ft- I started to gently experiment with possible solutions - the climb gave me time to think it through - and generate a bit of a plan. There were 3 options. I had a hook knife and provided I could reach to the boot of my harness I could cut the line. I could also pull the zipper tab - with great effort as I had to lift the dolly and get to the line or knot - that would take 2 hands but at least was theoretically possible. I could also use my chute. Since we were still climbing, and I was in control I tried to think through the consequences - if I cut the line in the wrong place and it hung up again and jerked the glider what would happen? - could I reach the boot? What would happen when you unload the glider by 100lb suddenly? Should I release then try or stay on tow and try? I also was trying to see what I could reach - which tended to put me out of position but gave me a good idea what was possible, and after some rehearsals I was feeling fairly confident I could shed the dolly - we were at around 5000ft by then.

My plan was - try to hook knife the cord at the boot - if not then release and use 2 hands to cut the knot at the draw tab and if I ended up below 2000ft, pull the chute.

The first option went without a hitch.

Analysis - Pilots action

1. The discussions / chit chat I had had with many people had included the actions to take if you end up taking a cart aloft. Therefore the thought of releasing or anything else except carry on climbing with the tow did not occur.

2. The time spent climbing was massively valuable - it took a while to build a plan and rehearse it.

3. I missed an easier option - the line is exposed all the way down the harness on the left side, from toggle to boot - see pic below of Alex's Z5. I could have cut it at my waist much more easily. This was out of sight... but would have been easier.

http://c2.staticflickr.com/6/5825/22761928668_57e03df835_o.png


4. Low down, early in the tow the only option would have been the chute. Betty' class told me that. It was clear that to land with the cart dangling and attached to the harness would have pitched me face down.

Analysis - What more could have gone wrong?

1. There were 3 significant factors that enable a good outcome:

-a. I had an accessible hook knife (if you have not got one - or it's tether is not long enough to reach everywhere you can reach (I use 1/8" bungee for the tether) please get one!

http://c2.staticflickr.com/6/5544/30851998081_5e97343263_o.png


-b. The air was smooth. Rough air would make control more marginal and more importantly with the extra weight of the dolly and compromised control may cause a rapid low height weak link failure. I use the light greenspot weak link and protow. I do not get breaks but I will change to the heavier green line like many others.

-c. I was over terrain that could safely accept a dolly.

Analysis - Immediate Cause

The immediate cause was the loop of zipper line that is at the boot of the harness. It is just visible in the pic below. Most times I will pull this up to the waist. I failed to do so this time. It caught on the bolt that protruded below the upright, where the threads were approx 1/8in exposed above the nut (circled)

http://c2.staticflickr.com/6/5448/22761928428_e190f4f0da_o.png


Here you see the loop at the boot of the harness. The white line is my cut line, the black one is another Z5 harness.

http://c2.staticflickr.com/6/5780/22761927938_069f11c712_o.png


My hypothesis is that the combination of the wind blowing it back and the harness boot swinging close to the dolly caused it to hook onto a small bolt underneath the V cradle upright. As the rear of the dolly was slightly lifted by this it rotated tail over nose, thereby wrapping the loop a half turn around the tube, making it very unlikely to fall off.

Analysis - Prevention:

1. By checks

-a. Sloppy preflight checks by me - I often pull the zipper line up - but it is not really in the preflight check - it is more of a "let's get tidy before launch" action. Easily forgotten

-b. Organise the zipper line inside the harness boot before laying down in the harness

-c. Ground crew: It is practically hidden from the front - so it is unreasonable for the GC to see it unless it is built into the hang check as part of 'lines'. We could do this, along with the release check

2. By design

-a. Remove or tape over or otherwise minimise all sticking out catch points (I will do this at the earliest opportunity!)

-b. Fit a smooth cup in the vee of the rear of the dolly (imagine a bucket cut to cradle the harness boot and keep it clear of all metalwork and rotating wheels

-c. Fit a weak link to the zipper line

-d. Extend the dolly wheelbase to give greater clearance between boot and frame

-e. Design the harness with no loose lines at the boot

Safe flying
Richard

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34876
Jeff Glidewell - R.I.P.

David Botos - 2016/11/10 17:45:25 UTC

If you do something to increase drag on the towed aircraft (glider), such as a pitch attitude corresponding to increased drag, while the tug pilot tries to maintain their airspeed, then the tow line tension should...

WILL.

...increase. Think of one car towing another with a rope/strap and the rear car starts lightly applying its brakes while the front one tries to keep going.

You'd have to take into account all the variables of the particular situation (tow line length, altitude difference between tug and glider, bridle geometry, glider drag at given pitch attitude, etc.) to determine if you're getting into the neighborhood of weak link breakage.

What if you used a weak link to...

Tost Flugzeuggerätebau

Weak links protect your aircraft against overloading.

...protect your aircraft against overloading, the way they do for sailplaning? Then you'd never get anywhere NEAR the neighborhood of increase in the safety of the towing operation in ANY situation that wasn't...

Dr. Trisa Tilletti - 2012/06

You and I have flown sailplanes for almost as long as we have flown hang gliders. We own two sailplanes and have two airplanes that we use for towing full-size sailplanes. In all the time that we have flown and towed sailplanes, we have not experienced or even seen a sailplane weak link break.

It's not that it doesn't happen, but it is a rare occurrence. 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.

...totally tits up - from which any moron should've actuated his easily reachable release a long time ago.

It's sounds like something you don't want to determine experimentally unless you've got the altitude to recover from a potentially sudden stall.

Oh. You mean like it says in the u$hPa AT rating requirements for...

The United States Hang Gliding and Paragliding Association, Inc. - 2016/10/22
Standard Operating Procedure
12. Rating System
02. Pilot Proficiency System
11 Hang Gliding Special Skill Endorsements
-A. Special Skills attainable by Novice and above (H2-H5).
05. Aerotow (AT)

-f. Must demonstrate the ability to control the glider position within the “cone of safety” behind the aerotow vehicle. The candidate must also demonstrate the ability to properly react to a weak link/tow rope break simulation with a tandem pilot, initiated by the tandem pilot at altitude, but at a lower than normal release altitude. Such demonstrations should be made in smooth air.

...simulating an increase the safety of the towing operation? (And make sure you don't forget the smooth air part. We all saw what happened to Zack Marzec the better part of four years ago when he suffered an increase the safety of the towing operation in abruptly good soaring conditions.)

USHPA weak link recommendations for aerotow:

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 glider pilot and glider combination. The weak link at the tow plane end of the towline should break with a towline tension approximately 100 lbs. greater than the glider end. Weak links must be used in accordance with 12 CFR 91.309(a)(3). The 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 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 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.

From SOP 12-10.04 section B4:
http://www.ushpa.org/legacy/documents/sop/sop-12-10.pdf

And here's what the fucking geniuses at u$hPa originally said about AT weak links when they were obtaining their exemption:

USHGA Aerotow Guidelines - 1985/07
from the USHGA Safety and Training Committee

II AEROTOWING EQUIPMENT

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.

Short translation... Not enough to be able to get a glider airborne. A Rooney Link would be illegally overstrength on ANY glider - including tandem.

So tell me how aerodynamics, glider certification standards have changed, evolved over the past three decades to account for the revision.

Also... Show me:
- one single word of explanation for one single u$hPa motherfucker regarding WHY u$hPa recommends what it does
- how any u$hPa AT operations are complying with the regulations and adhering to the recommendations

[Tad Eareckson]

The United States Hang Gliding and Paragliding Association, Inc. - 2016/05/11
12. Standard Operating Procedure
10. Towing Administration

03. Weak Links

A. A Weak Link is a breakaway point between the towing device and the towed aircraft. The purpose of the weak link is to protect against structural damage and might not prevent lockouts or other abnormal flight conditions. Pilot's under tow need to be prepared for all emergency situations due to, but not limited to, the early breakaway or non-breakaway of the weak link.

A Weak Link is a breakaway point between the towing device and the towed aircraft.

Where? Is it OK to have it 250 feet upwind at the towing device's tow mast breakaway protector? The way most gliders flying u$hPa's recommended AT weak link on their end do? Is a glider which has just gone into emergency mode OK trailing close to a football field's worth of two thousand pound Spectra no longer need weak link protection?

The purpose of the weak link is to protect against structural damage and might not prevent lockouts or other abnormal flight conditions.

But it MIGHT. So you really can't go wrong...

http://ozreport.com/forum/viewtopic.php?t=24846
Is this a joke ?

Jim Rooney - 2011/08/28 10:40:24 UTC

Is a weaklink going to save your ass? Who knows? But it's nice to stack the deck in your favour.

...stacking the deck in your FAVOUR.

Pilot's...

Pilot's WHAT - you semiliterate incompetent douchebags.

...under tow need to be prepared for all emergency situations due to, but not limited to, the early breakaway or non-breakaway of the weak link.

- So both being under tow or not under tow is an emergency situation. So much for responsible flatlands flying.

- If:

The purpose of the weak link is to protect against structural damage...

...and one is using a weak link of five Gs or under then how is it physically possible to have a "non-breakaway"? Do we have an example of a non-breakaway from anywhere in the history of aviation?

- At Quest on 2013/02/02 one of your Hang Four pro toad tandem aerotow instructors benefitted from an early breakaway of one of your standard aerotow weak links at 150 feet, whipstalled, tumbled, and died. Nobody has ever expressed a subatomic particle's worth of doubt that the motherfucker ever had the bar very far out of full stuff position at any point in the tow. So what was he supposed to have done differently to obtain different results?

- At Quest on 2016/05/21 a Hang Four pro toad comp/airline pilot at the end of a long abnormal flight condition immediately after his late breakaway of his Tad-O-Link. The author of the:

Risk Mitigation Plan for the Quest Air Open

under which he was operating stated:

http://ozreport.com/forum/viewtopic.php?t=48425
Oregon flying on the edge

Davis Straub - 2016/07/12 19:25:33 UTC

I am thinking that perhaps the conditions had little to nothing to do with this accident. I'm thinking that the pilot made a mistake, letting go of the bar with one hand. and the pitch became far too great far too fast.

This comes from what Russell told me, what April told me and what the first responders told Belinda.

What are you recommending he should've done differently in order to have been better prepared for the late breakaway of his Tad-O-Link?

- Would flying with a two point release that doesn't stink on ice fall under the heading of being better prepared for the late breakaway of the focal point of one's safe towing system? If so can you point us to any of your instructors teaching this or quote anything from your official towing manual - the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden - that supports this?

Total fuckin' u$hPa/Industry bullshit. Identical to instructions for successful playing of Russian roulette. Players engaged need to be prepared for that one-in-six event when... Blew his brains out the other side of his head? Obviously wasn't properly prepared - despite our high quality SOPs, instruction programs, risk mitigation plans.