Towing Aloft

General discussion about the sport of hang gliding
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Tad Eareckson
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Re: Towing Aloft

Post by Tad Eareckson »

Safety Tip: Beware of threading a string release directly through a weak link or loop in the end of a small diameter rope. Do not thread a large diameter cord through a loop made with a much smaller diameter cord. Under tension, the smaller diameter cord can pinch the larger diameter material enough that it may fail to release.
Yeah kids, NEVER thread a string release directly through a weak link. That would be unbelievably stupid and dangerous. That's the sort of thing that got Shane Smith killed on 2011/01/15.

And if you wanna see EXACTLY HOW *NOT* TO DO IT, check out Figure 7-24 - in which these morons illustrate a recommended one point aerotow configuration.
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Tad Eareckson
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Re: Towing Aloft

Post by Tad Eareckson »

HAND TOWING AND TETHERING - CAUTION!

Sometimes pilots get the idea of towing aloft - with or without wind - by hooking up a rope - with or without a release - to their glider and having friends pull on it.
Whereas if the glider is being pulled by a winch, boat, truck, or tug these variables are - by definition - absent from the equation.
This is especially attractive to paraglider pilots with the slow speeds and seeming simplicity especially attractive to paraglider pilots with the slow speeds and seeming simplicity of their craft. However, we highly discourage this practice outside of the school situation for two reasons: First, with several persons pulling the rope (one person isn't strong enough), THERE IS NO WAY TO DETERMINE OR SET A DEFINITE LIMIT ON THE TOW FORCE.
MY GOD!!! YOU'RE RIGHT!!! If only there were some way to determine or set a definite limit on the tow force. Maybe some kind of link at the end of the tow line that was weak enough to blow at a certain definite limit on the tow force. Lemme think about this one for a while. I'll get back to you if I come up with anything - but don't hold your breath.
If an emergency such as a lockout occurs, the pullers may not recognize it in time since they are preoccupied with their exertions. Even if they decide to let go, they may not all do so at once.
Whereas a winch, boat, truck, or tug driver will ALWAYS be giving you his complete and undivided attention so you can go up with any of the zillions of shitrigged releases described and illustrated in this stupid book and ALWAYS count on him to make the right call at the right time and do your job for you (whether you want him to or not).
Secondly, the short length of the ropes usually used in this practice leads to a dangerous situation because of the steep tow rope angle while the pilot is near the ground (see figure 1-6). The situation is more likely to produce lockouts, and when a lockout occurs it happens faster with less recovery time that with a longer towline that carries the pilot high before the steep towline angles or reached.
So much for platform launching.
There have been fatalities in both hang gliding and paragliding with hand towing due to lockouts.
Whereas nobody towing anything behind a winch, boat, truck, or tug has ever gotten so much as a scraped elbow.
Our best advice...
Yeah. Go ahead and impress me this time.
...is don't do it without expert guidance.
Yeah, somebody with a master's degree and is board certified in hand towing. (Or maybe someone with a little common sense who once flew a kite as a ten year old kid.)
If you insist on trying it with a paraglider, you should use a proper bridle and release system and proper towing techniques (see Chapter 4). Also, limit you altitude to twenty feet so tow angles are not steep.
Yeah. Definitely keep things low and safe on a short towline.
If you insist on trying it with a hang glider, limit the number of towers to three so as to limit the tow force. For both paragliding and hang gliding, do not fly in gusty winds or winds stronger than 2/3 the stall speed.
Let's call stall speed for a hang glider 21 miles per hour. So after fourteen I hafta call it a day. Yeah, sounds like loads of fun. Would it be OK if I got my third third of stall speed wind back in exchange for a third of my allotment of towers?
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Tad Eareckson
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Re: Towing Aloft

Post by Tad Eareckson »

While step towing, a pilot ignoring warnings from the winch crew, pulled the line all the way off the winch. Worried about the line snagging, he then released the line and draped 7000 feet of Spectra over the small town he was instructed to avoid. One can only imagine the damage and danger steel cable would have caused going over houses and several dozen power lines.
Ignored warnings from the winch crew? Pulled the line all the way off the winch? Out of cowardice and apathy dropped the line over a small town he had been instructed to avoid? What an INCREDIBLE ASSHOLE this guy must've been!!!

And here's what really happened.

I was a STUDENT at a step tow clinic run by Mike Robertson - or Greg Black. I could never really figure out who was running the show and it didn't look like they could either. Probably didn't matter much 'cause I thought they both sucked at it. Mike would tell me to do one thing and then stand by while Greg chewed me out for doing it.

On my first "step tow" - 1994/06/08 - I foot launched my HPAT 158 with Ray Jarvis coaching and Mike on a four cylinder winch three thousand feet away. I got off OK and was floating along at four feet waiting for Mike to pull me up. But Mike decided to keep me safe and dump tension. So he and Greg got to bill me for a tow and I got to replace a seventy dollar VG side downtube.

For my second "step tow" - the next day - there wasn't any air, 3 mph, so it was just a regular stationary winch foot launched tow to five hundred feet.

My third - that evening - the wind howled in at twice that and I dolly launched and got a few actual steps in - despite the towline snagging a runway light and the winch having to back off to deal with it - and made it all the way up to a whopping eleven hundred - where I released upon radioed instructions.

My fourth - the next day - was ninety cross strong enough to be iffy and there were dust devil conditions. I had jumped out of the car and stood next to a really cool one in a parking lot in town a short time before. I got gusted from the side as I was coming off the cart and my right/upwind wing came up. Mike, the same Mike who had previously dumped me when I really needed power, figured that this would be a really good time to hit the gas. I groundlooped and crashed pretty hard, taking out the new VG side downtube and banging a wrist or something pretty hard. (And I'm almost starting to wonder if he didn't do that deliberately.) I have now used up eighty percent of the step tows I was supposed to get for the price of the clinic.

(And this is another real good example of a pilot not being able to release in a low level lockout situation when the actuator isn't in hand or teeth.)

So that evening I'm back in gear and the winch "crew" was Ray Jarvis. I'm on the cart, the wind is lined up with the runway (NE) at six, and Mike and Greg are at launch.

- I radio Ray and tell him I wanna max out my steps and will turn on his call if that's OK. He says cool.

- I get a reasonable first climb and turn and run. He says turn back, I turn back.

- I get pulled in, make it to thirteen hundred, turn, and run.

- I don't hear anything for a long time and I AM getting a little suspicious.

- Then Mike comes on and tells me something to the effect of "Better turn it back now, Tad." I say roger and IMMEDIATELY start a 180.

- I get halfway through and feel this TREMENDOUS jolt. The glider rolls beyond ninety I think.

- Mike tells me the other end of the rope's off the winch and asks if I can bring mine back to the runway. I bring it back over the runway. I bring it back over the runway until he tells me to drop it. I take a swat at my two stage levers and think I've dumped it. He tells me I didn't get it so I take another swat and score that time.

I'm feeling about two inches tall.

Things and people are spread out. We have the winch end of the line still at the runway and engage it to the winch for a rewind. Mike radios Greg and tells him to cut the retrieval chute off the other end. Greg cuts the retrieval chute - but not the eye splice - off the other end. That may or may not have contributed to the disaster of the rewind but it sure didn't help any.

By the time that's off the to do list it's quite dark and I'm feeling about one inches tall.

I fucked up. I should've realized something was wrong and radioed back to the winch to see if everything was OK and turned around when I didn't hear anything. So, lemme repeat, I fucked up - and was stupid.

BUT...

- Even though I was a Hang Four at the time I was a STUDENT for the purposes of the clinic and it was a total shitrigged operation.

- You've got people launching three thousand feet away from the winch operator. The winch operator can save or kill the glider by dumping, easing, maintaining, or increasing tension. You NEED bulletproof communications between launch and the winch.

- The reason I didn't hear from Ray was 'cause he had put the handheld two meter down on the winch and it had vibrated off and fallen to the ground. And Ray deemed it too dangerous to abandon the winch controls to recover it.

That was ONE HUNDRED PERCENT INEXCUSABLE.
...a pilot ignoring warnings from the winch crew...
BULLSHIT.

- Crew? That's a rather dignified term for one person who hasn't been trained to keep the radio clipped to his belt and a headset on for the duration of the tow.

- And the other half of the ground "crew" - the observer - wasn't busy warning me about - or even watching - ANYTHING. Mike was busy gabbing with Greg. And Mike should have been and said he should have been watching me.
RADIO COMMUNICATION

Communication between the tow operators and pilot is essential, especially with long towlines. Using radios is the only way to communicate in these situations.

The importance of good radio equipment can not be over-stressed.
Yeah, as long as you've got good radio equipment it doesn't matter if it's lying on the ground or hanging on the belt of someone who's out to lunch.
Worried about the line snagging...
BULLSHIT.

Well, actually, I WAS worried about the line snagging. But that didn't influence my actions.
...he then released the line...
BULLSHIT.
...and draped 7000 feet of Spectra over the small town...
BULLSHIT.

The seven thousand feet of Spectra was draped in a J from the runway to the woods south of the runway and back to the runway.
...over the small town he was instructed to avoid.
BULLSHIT.

There were NEVER any instructions to avoid the town. (Or the prison off the other end of the runway. A couple of guards had paid us a visit 'cause the retrieval chute had been seen popping open after a tow and was believed to have been something (drugs, guns) being dropped into the yard.) I actually DID get over the town but the line never came anywhere near it.
One can only imagine the damage and danger steel cable would have caused going over houses and several dozen power lines.
Ya know what?

- It's been a while but I don't recall ANY houses OR power lines (and when you're that humiliated you tend to remember those sorts of things).

- Several dozen power lines? Let's call several "two". Ya think I coulda hit twenty-four power lines with 1.32 miles of towline if I was really good and trying for a world record?

Alternate Scenario One.

We were releasing on radio instruction from the winch. I do everything right this time. The radio winds up on the ground near the end of what was supposed to have been my last upwind run. I still pull all the line off the winch. There's a retrieval chute on the top end. If I dump the line it DOES end up on the ground draped from the airport to the town and beyond - and it's in the approach pattern while it's coming down. If I keep the line and work on neatly depositing it at the airport it's in the approach pattern longer.

Alternate Scenario Two.

Ray could've locked up the winch while I was running. Granted, that would've started me in a dive but:
- I was high and had a good two stage release.
- He coulda backed off again if I didn't get the message.
- It was no picnic when the line separated as it was. And that was when I was as low as I was gonna get. And - as it happened - sideways.

Alternate Scenario Three.

I don't think they/we were using weak links for two reasons...
- I don't have anything about weak links recorded in my log.
- The jolt I got when the line came off was like nothing I had experienced before or since.

If this had not been the shitrigged operation it was there would've been something on the pulled end which would've blown before something on the pulling end - the way they do in REAL aviation for sailplane aero (and the way we're supposed to do for hang gliding aero - but don't). That way no matter what the glider did there would be a normal line retrieval.

Alternate Scenario Four.

Any time you're running a step tow operation the only thing that's keeping the glider - and maybe airport and/or town - from ending up with a mile or more of rope is the towline not failing near the end of the spool.

And according to Ray at the time I was far from being the first person to pull all the line off their winch.
One can only imagine the damage and danger steel cable would have caused going over houses and several dozen power lines.
Maybe there are some real good reasons why it's a lot more common to find people launching 250 feet from Dragonflies than 3000 feet from winch operators with over twice that much line at their disposal.

For nearly seventeen years now I've felt pretty stupid and guilty about that one but... Nah.
- I was a student.
- Mike crashed me on my first flight all by himself.
- Mike put me up into marginal conditions on my fourth and powered me into a lockout when I had a problem.
- The string fiasco wouldn't have happened if:
-- Ray had told me no go on the turn on radio command request;
-- Mike wasn't totally stupid on the radio protocol for his winch drivers;
-- The official observer for the flight - Mike - hadn't been asleep at the switch;
-- Mike had established a common sense weak link protocol for his system.

And in the course of responding to this condensed work of fiction it finally occurred to me that if *I* had been running this operation I'd have considered myself ONE HUNDRED PERCENT RESPONSIBLE for what happened and would've worked very hard to take the heat off the ropee.

And after I read - in horror - this convenient and grotesque distortion of the incident and asked Dennis, face to face, if I was the subject - he lied. Same way he lied here...
pagenbks@lazerlink.com
2006/08/18 13:43:32 UTC

T,
I am in Switzerland for the World aero meet. Will be back on the 29th. I wont stiff you on the money. I just want to talk about some things. No wildlife here except swans...
Dennis
(And I don't mean about the swans.)

Furthermore...

This was a major pain in the ass but the only person who was ever put at any kind of risk was me and only because:

- I (almost certainly) wasn't provided with a weak link (there could've been a line dig or other winch malfunction that could've given me a much nastier jolt - especially if I had been pointed downwind); and

- I cooperated (quite willingly) in flying my end of the towline back to the runway.

Compare/contrast...
Hang Glider Foot Launch Checklist

Check:
01. To assure the launch procedures and flight plans have been reviewed with the tow team.
02. The protective equipment including helmet, gloves, eye protection, hook knife, etc. to make sure they are adequate and in place.
03. To assure the preflight inspections have been completed.
04. The harness for leg straps and locked carabiner.
05. Perform a hang check.
06. The tow bridle, release and fresh weak link for integrity and proper connection.
07. The towline retrieval chute, if used, for proper rigging.
08. To assure the tow team checks have been completed and the team is ready.
09. The air traffic. The marshal and other pilots should help here.
10. The conditions. Make sure the wind is light enough, smooth enough and straight enough for a safe tow.

When ready, issue the command, "clear" or "all out."
Hang Gliding - 1992/09
Tad Eareckson

In the period from 1980 to the present there have been reported four fatalities resulting from total failure to clip into anything and one from failure to step through either of the leg loops (the same problem on the other end).

In doing a traditional hang check there are several obligatory operations between the check and the launch. One must regain one's footing, stand up with the glider, and possibly walk a few steps to launch position. This delay between the check and the launch has been a factor in fatal accidents in the past. Additionally, hanging from the straps does nothing to ensure that one has found his or her way through the leg loops. A secondary visual or tactile inspection must be made.

My hang check method consists of simply lifting the glider immediately prior to launch until I feel the suspension and leg straps tighten. The delay is eliminated and the secondary check is made automatically.
I witnessed a tug pilot descend low over trees. His towline hit the trees and caught. His weak link broke but the bridle whipped around the towline and held it fast. The pilot was saved by the fact that the towline broke!
Hang Gliding - 1997/02
Tad Eareckson

To further address the danger of a primary release failure, a secondary weak link, of strength somewhere between significantly stronger than and double that of the primary, should be installed at the other end of the primary bridle. Note that a double strength link will fail at a somewhat higher tow tension than is allowed by the primary, as the primary bridle has ceased being a bridle and is now an extension of the towline (as explained in Dennis Pagen's and Bill Bryden's November article), but you'll still be in a reasonable ballpark. Also note that this secondary link may make the effects of the snagging of a trailed primary bridle (the potential for which is illustrated on the December issue's cover) a lot easier to live with.
You dumb sonsabitches couldn't have let either or both THOSE be my contribution to your stupid book?
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Tad Eareckson
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Re: Towing Aloft

Post by Tad Eareckson »

Performance Flying - 1993/04

Release Criteria

The trigger line should always be connected to a shoulder strap or some other appropriate easy to reach place on the body. It should not be connected to the pilot's wrist, for a severe stall while on tow can result in an inadvertent release as shown in figure 10-15. Once you are hooked into your bridle, it should be moved in all extreme positions to make sure it doesn't release on its own.
On 1990/03/29 - three years and two days prior to publication of this book - Brad Anderson, a 24 year old Oregon pilot, was truck towing and was OBVIOUSLY using this unbelievably stupid configuration. There was a bullshit fatality report submitted by the assholes who set him up that way who alleged that he "Pushed out hard enough to release and continued to push out after release."

On 1990/07/05 - ninety-nine days later - Eric Aasletten, another 24-year-old flying on Day One of the Hobbs Hang Gliding Festival - was configured and killed the SAME WAY (big fucking surprise).

The incredible douchebags who put out the 1990/10 issue of Hang Gliding magazine had a spectacular COVER PHOTO of a glider coming off the back of a truck with THE SAME RELEASE CONFIGURATION THAT HAD JUST KILLED THESE TWO PILOTS INSTANTLY and included an idiot article by Jerry Forburger - whom Dennis identifies as a "tow guru" but is, in fact, a total asshole - about how we need to TEACH pilots not to release when they're standing on their tails after being blasted by dust devils (but it's still totally cool to put the lanyard on your wrist 'cause that's the way most people do it).

Figure 10-15 shows EXACTLY what these two guys looked like four seconds before they whipstalled back into the runway.

So let's jump ahead to four years and nine months...
Towing Aloft - 1998/01

RELEASE LINES

Some pilots prefer tying a loop in the end of the release cord and placing this around one wrist. The benefit is they need not reach for the line and only have to yank their arm back to effect a release. There are problems with this practice. For example, if the pilot enters a strong turn on launch, it is unnatural and contrary to most survival instincts to remove a hand from an upright on the low side to activate the release. If the release line is tied to this wrist, you tend not to release when you should. Again, heed the voice of experience--we've been there! The second consideration is possible injury to the pilot's wrist. If the bridle snags while flying with the line attached to the wrist, you can suffer a bad injury. Additionally, if for some reason (say a release failure) the pilot needs to use his knife to cut the bridle free, he must first remove the cord from his wrist. If you insist on a wrist attachment, it should be done with a Velcro band or with a weak link that will free the line if 30-40 pounds of force are on it.
UN FREAKING BELIEVABLE.

I don't think Bill could figure out which way was up if he sat down on a land mine but an least Dennis KNOWS what WILL HAPPEN when someone gets hit.

So just what the fuck is going on here?

GOT IT!!!

USHGA has NEVER been interested in making hang gliding safe or sane, it's interested only in attracting participants and protecting itself and the establishments that feed them in.

- The idiots that "teach" this crap, rate students, send them to USHGA to buy proficiency cards, magazines, mugs, and T-shirts have always put lanyards on wrists (and levers on downtubes) and always will and USHGA's not gonna identify these things as the death traps they are 'cause that'll piss off assholes like Steve Wendt and open them - and USHGA - up to liability, and cut the income from new recruits.

- Dennis sells books. Dennis sells books through flight schools, tow parks, and USHGA. Dennis isn't gonna gonna publish in his books that what the USHGA certified flight school that's selling his books is "teaching" is likely to get the student killed. If he does, the flight school won't sell his books.

- And basically, neither USHGA nor any of its rotten corrupt tentacles want anybody, members, participants, potential recruits, the general public, the FAA... to think this game is dangerous. And it's just so much easier to suppress accident information and data, put lipstick on shitrigged equipment, procedures, and instructors, tell people not to worry 'cause their weak links will save them, and paint dead and crippled pilots as incompetent losers who had it coming anyway to give the ILLUSION that it's safe - than it is to fix the problems and actually MAKE it safe.

AND NONE OF THAT IS *EVER* GONNA CHANGE.
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Tad Eareckson
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Re: Towing Aloft

Post by Tad Eareckson »

Towing Aloft - 1998/01

You should ALWAYS hook your harness into the glider before you hook up the towline. This procedure is very important to prevent the dire consequences of forgetting to hook into the glider if you ever foot launch.
Right kids. You should ALWAYS hook your harness into the glider before you hook up the towline because this procedure is very important to PREVENT the dire consequences of forgetting to hook into the glider if you're not using a platform or dolly.
Donnell Hewett - 1985/04

Note that there was one out of four towing fatalities this year which resulted from failure to hook in. In the case of tow launching, the rule is: ALWAYS HOOK-IN BEFORE YOU HOOK-ON. In other words, make it a habit never to HOOK-ON to the towline before you HOOK-IN to the glider.
Follow this rule - ALWAYS. Make it a HABIT. Do it that way EVERY TIME so by the time stomp your foot to signal the driver that you're ready for him to hit the gas you can be ABSOLUTELY SURE you're hooked in.
Donnell Hewett - 1985/04

For example, I can understand why someone failing to hook-in will hold on to the glider when he is running off a ramp or cliff, but why would he hold on when tow launching from level ground? (I - yes, I, too - have failed to hook-in on tow launch, but I never kept holding on to the glider when it lifted off without me.)
And, as previously noted in the second post of this thread, Dennis screwed this pooch bigtime slope launching at Morningside on 1993/09/28 four years and three months before publication of this stupid book, very belatedly found hook-in check religion, and published an article in Hang Gliding magazine about how to reprogram yourself using post-hypnotic suggestion.

And, as previously noted in the second post of this thread, there's not a single solitary reference in this entire stupid book to a hook-in check.

And in a bit less than ten years after publication of this stupid book Bille Floyd's gonna by lying on a dry lake bed with splinters of his shin bones sticking six inches out of the bottoms of his shoes 'cause he was ABSOLUTELY SURE he was hooked in because of the procedure he follows EVERY TIME while he's preparing for launch.

So isn't it a bit odd that four years after Dennis's magazine article there are absolutely no mentions of hook-in checks?

Not when you understand what these bastards are doing and why (see previous post). Matt Taber and Steve Wendt don't comply with USHGA regs and teach hook-in checks, Matt and Steve have students who break their backs and kill themselves launching unhooked, and Matt and Steve sell books.

And Towing Aloft thus describes only what people are doing - and carefully avoids describing what people SHOULD BE doing.

This pattern is starting to fall into place very nicely. Stay tuned.
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Re: Towing Aloft

Post by Tad Eareckson »

Towing Aloft - 1998/01

COMMENCING THE LAUNCH--PLATFORM LAUNCHES

You will likely encounter some pilots possessing passionate convictions about the appropriate tensions for launch. That is fine, and for their equipment, conditions, tow site, etc. those tensions may be warranted. Before deciding to tow, just watch some of their tows. If, after their typical launches, the glider hovers and dawdles behind the vehicle on a short leash is not safe. If the spectacle of their launches and climbouts remind you of the Space Shuttle, be equally wary. A weak link break or slight roll during nose release can be traumatic and damaging to people and things. There are many schools of thought about launch tensions, speeds and techniques. We have tried to integrate what we believe are the best aspects of the different philosophies with our own towing experience to provide these recommendations.
Zack C - 2011/03/04 05:29:28 UTC

As for platform launching, I was nervous about it when I started doing it. It looked iffy, like things could get bad fast. I've since logged around a hundred platform launches and have seen hundreds more. Never once was there any issue. I now feel platform launching is the safest way to get a hang glider into the air (in the widest range of conditions). You get away from the ground very quickly and don't launch until you have plenty of airspeed and excellent control.
A platform launch is the towing equivalent of what USHGA refers to in its Special Skills listings as an "Assisted Windy Cliff Launch".

An Assisted Windy Cliff Launch makes people nervous and looks iffy but when you've got a pilot and crew - particularly the latter - who know what they're doing and the air is strong but not ridiculous and reasonably predictable it's the safest way to get a glider into the air without using a string.

Get the glider positioned properly on the ramp, level, trimmed, pick a cycle... The glider's going up. The pilot doesn't hafta run and isn't given the opportunity to screw anything up before he's at least thirty feet over the ramp.

Platform launch...

- The pilot starts prone with both hands on the basetube - just like the way things were configured when the glider was certified.

- None of the hang checkers and Aussie Methodist douchebags who refuse to do hook-in checks have the option of NOT doing a hook-in check.

- It's impossible to start too for back from the edge.

- There:
-- are no options for starting off with the glider rolled and no easy ones for screwing up the pitch
-- tend not to be really big rocks around the launch area
-- is no:
--- back to get blown over
--- possibility of anyone letting go of a sidewire to soon or late
- You can dial in whatever wind speed and upward deflection angle you want with a combination of the airspeed indicator, gas pedal, and pressure gauge.
There are many schools of thought about launch tensions, speeds and techniques.
This is a little like talking about the ideal wind speed and slope grade for a ramp launch. The glider - and pilot - can handle a wide range but, to a point, the more airspeed and lift the merrier.
If the spectacle of their launches and climbouts remind you of the Space Shuttle, be equally wary.
When the Space Shuttle's going up like the Space Shuttle everybody - astronauts, engineers, people in the control room staring at monitors - is very happy.
A weak link break or slight roll during nose release can be traumatic and damaging to people and things.
- A weak link break can be a BAD THING? BULLSHIT. Just read Towing Aloft:
Fortunately, we have good defenses against lockouts. These defenses include limiting the tow forces by using weak links and pressure gauges, proper distribution of the tow forces and proper training of pilots.
Structural failure under tow is a thing of the past due to our systems to limit the tow force (weak links and pressure gauges).
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.
Weak links have greatly improved the safety of towing over the years.
Weak links very clearly will provide protection from excessive angles of attack, high bank turns and the like for this form of towing (speed controlled).
If they differ by more than ten percent you do not have a reliable and predictable weak link system. The hazard of having a link breaking at much higher tensions is obvious.
The selection of the breaking threshold is not an exact science. Rather it is a subjective decision based upon the method of towing, the tow tensions being used, the loading on the glider and simply the comfort level of the pilot.
A weak link provides a measure of additional safety in all towing situations.
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.
Three recent aerotowing accidents have occurred--one fatal. The common thread in all three was a lockout and the use of a much too heavy weak link.
Your glider and life are not cheap; don't tow without a safe weak link.
"It is infinitely better to have a weak link break too soon rather than too late."
-- Towing Proverb
A second procedure sometimes advocated is for the tow crew the crank up the tension and break the weak link for the pilot.
A weak link is an integral part of any towing system in order to prevent overloading and lockouts.
A weak link is a fuse that protects the equipment--your body!--on an overloaded circuit.
In the case of lockouts or turbulence, the weak link breaks as designed and should not be increased in strength.
Aerotowing Weak Link Lore

Use an appropriate weak link to break at a low tow force about equal to combined glider and pilot weight.
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.
Weak links are an essential part of the safe towing formula.
And OBVIOUSLY the lighter it is the fewer lockouts, structural failures, dangerous towing systems and formulae, unsafe and undesired thresholds, years of dangerous towing, excessive angles of attack, high bank angles, obvious hazards, disasters, uncomfortable and panicking pilots, fatalities, broken gliders and bodies, late releases, proverb and lore contradictions, overloading incidents, and people flying through turbulence you're gonna have and the easier you're gonna make it for assholes who fly with shitrigged releases to blow tow when they fail.

Can't USHGA revoke your rating for for spouting dangerous subversive remarks like that?

- Slight roll coming off the truck. Terrifying. I've had so many friends maimed and killed that way.

Meanwhile, back at reality...

In REAL aviation - and even slope launch hang gliding - the idea is to build up tons of airspeed and blast off the runway with all the power you can muster. But in tow launch hang gliding you've got a weak link to keep you safe and...
As the towline wears from abrasion and UV exposure, its breaking strength diminishes. Typically pilots continue using a line until it begins to break on a regular basis at normal tow tensions. Given the general tendency by pilots to save money, it is probable that you will experience a line failure during a towing career.
...some cheap stupid asshole that doesn't understand and/or care that a frayed towline can - under the right circumstances - kill you just as dead as frayed sidewire.

So we've gotta dial the tension down and stay in the kill zone a little longer for the sole reason that the douchebags conducting this sport are totally incapable of understanding THIS:
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
and doing anything about it.
Caution: The slower you fly, the more likely lockouts are to occur. The slowest possible flying speed on tow should only be used in smooth conditions once you have gained experience tracking the towline.
But we can't fly fast near the ground 'cause our fucking weak link might blow to keep us safe.
Paragliders have less total weight than hang gliders, so it is logical that their weak link breaking strengths should be lighter. In addition, as we shall see in later chapters, a paraglider can be towed too fast or with too much force so that the pilot is well in front of the canopy. In such a situation, there is a great danger of canopy surge and collapse if the weak link breaks. If such an event happens close to the ground, the results could be disastrous. The only defense in this case is to use less tow force and a weak link that will break BEFORE the tow force gets too great. Thus, we recommend a weak link that is 75% or less of the total weight of pilot and glider.
In any case, remember: aerotowing requires a much lighter weak link than surface towing. Also, most ultralight sailplanes use a direct hookup (without a bridle), so all the towline force will be taken by the weak link. Finally, be aware that a low separation from the tow line is more of an emergency with an ultralight sailplane than a hang glider or paraglider because of landing area requirements. Thus, more care should be given to weak link selection so as to minimize premature breaks, and still maintain a low upper breaking limit.
MINIMIZING WEAK LINK FAILURE

Weak links often break near the beginning of a tow, when the glider is still low and the resulting release is typically uncomfortable for the pilot. To reduce these failures, follow the following suggestions.

- Remove slack between the glider and tow vehicle or winch to reduce shock loads when the tow begins.

- If launching from a dolly, be certain the wheels or straight, not in a hole and consider having an assistant provide a gentle push as the tow begins, to overcome the initial friction and inertia.

- If launching from a platform, be pulled in aggressively as the nose is released to reduce the sudden blast-off from the platform.
The chest or shoulders area bar position should yield an airspeed well above trim, if not, then pull in a bit further during the ground roll. You want to have plenty of airspeed to help carry you away from the dolly should a premature release or weak link break occur just after launching. It is not fun landing knowing a rolling dolly is about to clip your heels and legs from behind. The extra airspeed allows you to fly further away before landing.
Flying at a speed similar to best glide provides more margin for corrective action and avoids a low altitude stall should the weak link break or the release prematurely disengage.
As you become more experienced and tow in a wider variety of weather related conditions, you'll probably want to increase your launch speed to approximately 30 mph or moderately more. The increased airspeed improves your ability to manage gusts and crosswinds. It also provides more time and room to land if the weak link breaks or the release disengages. However, higher release airspeeds will exaggerate poor technique and make launches more violent as well as increase the potential for weak link breaks or even mild whip stalls after launch.
In addition, the tensions should still be kept low for the launch and increased only after sufficient altitude is achieved (at least 100 feet). The dangers of releasing or breaking a weak link and surging due to high forces when you are low should be apparent. Remember: there is safety in altitude. The converse of this rule means the greatest risk occurs near the ground, so tow gently when down low.
With a paraglider, the problem isn't so much maximizing climbout as it is avoiding over-climbing. With a reel-in or payout winch, the operator must be very careful to avoid towing the paraglider too fast as this action will pull the pilot in front of the canopy (see next chapter). The result will be too high an angle of attack, which in turn causes loads on the canopy to rise and increase the risk of lockout or canopy collapse if the weak link breaks.
If the weak link breaks or you release under high tension, especially when towing low, the canopy will surge more violently.
The tow site must not have trees, power lines or other obstacles close to either side of the tow path. Crosswinds will cause an airborne glider to drift downwind of the tow path and obstacles could present a hazard to the glider or snap a towline. Obstacles upwind can create turbulence. This may interfere with safe launching or landing if the release disengages or weak link breaks before enough altitude has been achieved to reach a clear area.
As discussed earlier in this chapter, a paraglider pilot should use as little brake as possible to minimize a forward surge should the release disengage or weak link break. Similarly, if these events occur to hang glider pilot, he or she will more likely stall before lowering the attitude of the glider. Such risky flying must be avoided at low altitudes.
LINE BREAKS

The use of lighter tensions until some altitude has been achieved greatly reduces the probability of this occurring immediately after launch. The event is similar to a weak link break or release disengagement. Recover as you would with those occurrences.
The more serious tension control failure is when the tow force climbs beyond normal or desired levels. You will find yourself climbing like a rocket ship and it is very unnerving. If the glider is in line with the tow force and flying straight and level, just stay with it and radio the tow crew to reduce tension. Pulling in aggressively on a hang glider or pushing the speed bar on a paraglider is wise. The weak link may likely fail at any moment and having the extra speed can reduce the high potential of a stall or surge when it lets go. It is generally not wise to release unless the glider begins to turn or bank away from the line. The longer you hang on the more altitude you gain which affords a greater safety margin as well.
A weak link break or slight roll during nose release can be traumatic and damaging to people and things.
In the old days, "deep water" starts were common. The glider floated on the water with the pilot wearing water skis hanging below. The launch was effectively equivalent to a water ski start. Tow forces required to get the glider and pilot moving through the water and up were rather high, potentially beyond the breaking point of the weak link.
When gliders are returning and landing on solid ground, do not be tempted to avoid the use of appropriate flotation. A weak link break or premature release could easily precipitate a landing in the drink.
Momentary variances of 30 to 40 pounds are certainly noticeable to the pilot but are generally not a problem at all. However, definitely avoid variances which increase the tension excessively and may break the weak link.
While aerotowing, the weak links break most often when the launch begins on a dolly or during a lockout or turbulence. In the first case, you can relieve unwanted breaks by making sure the towline is tight before the tug pilot adds power and having an assistant push the dolly to help overcome friction and inertia as launch begins.
Inadvertent weak link breaks slow a group operation down and may compromise safety if they happen critically low.
- Get the goddam weak links up to one and a half Gs and every one of those problems virtually disappears. Eliminate the goddam things altogether and every one of those problems totally disappears.
Weak links have greatly improved the safety of towing over the years.
- Yeah, right.

- Nowhere in this entire stupid book is there a single example of weak link doing the job for which it's ACTUALLY intended - to keep the plane from being overloaded.
I witnessed a tug pilot descend low over trees. His towline hit the trees and caught. His weak link broke but the bridle whipped around the towline and held it fast. The pilot was saved by the fact that the towline broke!
- And when one of the morons running one of the operations from which the morons writing the book learned everything they know actually DOES REALLY NEED a weak link he doesn't have one 'cause he's too stupid to grasp the "ends of the towline" concept.
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Tad Eareckson
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Re: Towing Aloft

Post by Tad Eareckson »

Watch the chronology.

Back when dinosaurs ruled the planet...
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
...people understood from reading the fatality reports...
1977/09/25 - M. Horvath - 38 - Lake Eppilock - Victoria

Boat tow. Line broke or was released prematurely. Dived in from 200 feet.
1978/04/06 - Bill Flewellyn - 31 - Moyes Stinger - Toowoomba - Queensland

Vehicle tow during exhibition. Rope broke at 100 feet. Dived in. Hang IV pilot. Had flown over Mount Fuji, balloon-dropped from 23,000 feet.
1978/06/06 - John Walbert - Martha Galvis - Seagull III - Lahaina - Maui

Boat tow. New driver. Too fast. Splice in towline snapped at high angle of attack. Tandem flight. Both died.
...and using a billionth of their brains' processing capacities that when the string pulling a kite into the air breaks the kite is definitely gonna go back down and probably crash. So EVEN WHEN PEOPLE WERE TOWING FROM THE CONTROL FRAME and were thus HIGHLY PRONE TO LOCKOUTS and the gliders were put together with bamboo, plastic sheeting, and duct tape people recognized that STILL:
The greatest dangers are a rope break or a premature release.
The releases were excellent and the actuators were located such that you could follow this rule:
"Never take your hands off the bar." - Tom Peghiny
...so lockouts could be easily preempted most of the time and, even though weak links weren't used at all, a halfway competent driver wasn't gonna tear your chintzy glider apart.

But hang gliding has never been real comfortable basing anything on data, thought processes, or common sense so...

Enter religion and shitrigged releases.
Donnell Hewett - 1981/04

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," and that "More people have been injured because of a weak link than saved by one." Well, I for one have been saved by a weak link and would not even consider towing without one. I want to know without a doubt (1) when I am pushing too hard, and (2) what will break when I push too hard, and (3) that no other damage need result because I push too hard.

In skyting we use a simple and inexpensive strand of nylon fishing line which breaks at the desired tension limit. There is no possible way for it to jam and fail to release when the maximum tension is exceeded. Sure, it may get weaker through aging or wear and break too soon, but it cannot get stronger and fail to break. If it does break too soon, so what? We simply replace it with a fresh one.
Ignore any data that you don't like, use whatever cheap inaccessible dangerous crap you want for a release, and pretend that nothing bad can happen to anyone as long as he rigs his towline to blow every time the tension gets five or ten pounds over normal.

Frequent abrupt, total, and irretrievable loss of thrust on takeoff is - for the first time in the history of aviation - now and forever afterwards a GOOD THING. Marginal tow tension, releases that autoblow when the nose comes up, trigger-happy tug drivers, fuzzy string weak links - NOTHING TOO GOOD TO KEEP US SAFE and protect us from the unknown horrors of climbing out quickly and smoothly.
Performance Flying - 1993/04

Lockouts

Next to a low stall and line break due to a gust, the event most likely to maim on tow is a lockout.
Oops. A little hint of residual sanity. Even after a dozen years of the ravages of Skyting "Theory" Dennis lets slip that losing the tow is still more dangerous than a lockout. He's still saying the same thing...
The greatest dangers are a rope break or a premature release.
...that was quoted in Manned Kiting nineteen years prior.

But notice that you can get maimed ONLY as a result of a "line break" "due to a gust".

- You're still in GREAT SHAPE after a WEAK LINK BREAK due to a gust or, obviously, a thermal, dust devil, tension surge, or lead footed driver. 'Cause a weak link break is - remember - ALWAYS a GOOD THING.

- And the worst thing that can happen to you towing - either as consequence of a line break or lockout - is a MAIMING. NO WAY can you get KILLED. 'Cause the idea is to attract as many participants (customers) as possible - not to educate and make the environment safe for them.

Forward to Towing Aloft - 1998/01...
As the towline wears from abrasion and UV exposure, its breaking strength diminishes. Typically pilots continue using a line until it begins to break on a regular basis at normal tow tensions. Given the general tendency by pilots to save money, it is probable that you will experience a line failure during a towing career.
Now you can no longer get even MAIMED by a line break due to a gust - or anything else. Now a line break is NEVER a BFD. The reason being, of course, that a bunch of shitrigged tow operations wanna keep as much dangerous substandard equipment in operation as long as possible to minimize operating costs.
The United States Hang Gliding and Paragliding Association, Inc.
Standard Operating Procedure
12. Rating System
02. Pilot Proficiency System
10. Hang Gliding Aerotow Ratings
-B. Aero Vehicle Requirements

08. The tow line must be at least twice as strong as the weak link in use.
Yeah, right. Like anybody's even gonna bother to READ - let alone adhere to or ENFORCE - any safety regulations in hang gliding.
In such a situation, there is a great danger of canopy surge and collapse if the weak link breaks. If such an event happens close to the ground, the results could be disastrous.
Finally, be aware that a low separation from the tow line is more of an emergency with an ultralight sailplane than a hang glider or paraglider because of landing area requirements.
Weak links often break near the beginning of a tow, when the glider is still low and the resulting release is typically uncomfortable for the pilot.
You want to have plenty of airspeed to help carry you away from the dolly should a premature release or weak link break occur just after launching. It is not fun landing knowing a rolling dolly is about to clip your heels and legs from behind.
Flying at a speed similar to best glide provides more margin for corrective action and avoids a low altitude stall should the weak link break or the release prematurely disengage.
The increased airspeed improves your ability to manage gusts and crosswinds. It also provides more time and room to land if the weak link breaks or the release disengages. However, higher release airspeeds will exaggerate poor technique and make launches more violent as well as increase the potential for weak link breaks or even mild whip stalls after launch.
The dangers of releasing or breaking a weak link and surging due to high forces when you are low should be apparent.
With a reel-in or payout winch, the operator must be very careful to avoid towing the paraglider too fast as this action will pull the pilot in front of the canopy (see next chapter). The result will be too high an angle of attack, which in turn causes loads on the canopy to rise and increase the risk of lockout or canopy collapse if the weak link breaks.
If the weak link breaks or you release under high tension, especially when towing low, the canopy will surge more violently.
Obstacles upwind can create turbulence. This may interfere with safe launching or landing if the release disengages or weak link breaks before enough altitude has been achieved to reach a clear area.
As discussed earlier in this chapter, a paraglider pilot should use as little brake as possible to minimize a forward surge should the release disengage or weak link break. Similarly, if these events occur to hang glider pilot, he or she will more likely stall before lowering the attitude of the glider.
Pulling in aggressively on a hang glider or pushing the speed bar on a paraglider is wise. The weak link may likely fail at any moment and having the extra speed can reduce the high potential of a stall or surge when it lets go.
A weak link break or slight roll during nose release can be traumatic and damaging to people and things.
Tow forces required to get the glider and pilot moving through the water and up were rather high, potentially beyond the breaking point of the weak link.
A weak link break or premature release could easily precipitate a landing in the drink.
Momentary variances of 30 to 40 pounds are certainly noticeable to the pilot but are generally not a problem at all. However, definitely avoid variances which increase the tension excessively and may break the weak link.
While aerotowing, the weak links break most often when the launch begins on a dolly or during a lockout or turbulence.
Inadvertent weak link breaks slow a group operation down and may compromise safety if they happen critically low.
So you may experience disastrous results, suffering from inadequate runway problems, discomfort, dolly attacks, low altitude stalls, mild whip stalls, violent canopy surges and collapses, dangerous launches and landings, trauma and damage to people and things, unplanned water landings, slowed group operations, and compromised safety and inability to launch from water, get a dolly rolling without assistance, and survive tension fluctuation.

But most of this will be YOUR FAULT for trying to tow with enough tension to climb through the kill zone quickly, flying in thermal conditions, failing stuff the bar fast and far enough when you get hit, not using strong enough dolly launch assistants, and attempting to boat tow from anything but a platform or beach.

But DON'T EVEN THINK about going to one and a half Gs 'cause that exceeds the Sacred Range of 0.2 to 1.2 revealed by God to Saints Dennis and Bill by anywhere from 0.3 to 1.0. 'Cause if you do you will instantly lock out and die - and probably take a tug driver with you - especially if you wanna continue flying with your cheap shitrigged release.

And, besides, he doesn't actually say anything about maimings or killings - so what the hell.

Forward seven years...
Dennis Pagen - 2005/01

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.

Analysis

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 sixty 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. 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.
- As we've seen above, Towing Aloft is oozing with descriptions of "mild whip stalls" and other petty annoyances that can result from "required" 0.8 to 1.0 G aerotow weak links.

- I know for an absolute fact that Dennis is a 130 pound Greenspot clone 'cause I rigged him up with one of my one point assemblies at Ridgely the following year.

- His flying weight - as he reports in the 1996/11 issue of Hang Gliding - is 255 pounds.

- I don't know anyone who hooks in at much over a hundred pounds when the sun is more than five or ten degrees above the horizon who isn't holding his or her breath the entire tow and praying the 130 pound Greenspot holds.

http://www.chgpa.org/forums/viewtopic.php?f=2&t=3600
Weak link question
Danny Brotto - 2008/11/04 12:49:44 UTC

I had the Axis on the cart with the AOA a bit high, launching to the west, with a moderate 90 degree cross from the left. I came out of the cart rolled and yawed to the right with the upwind wing flying and the downwind wing stalled. It was rather dramatic. If I had released or if the weak link had broken, the downwind wing would have further stalled and I would have cartwheeled into terra firma in an unpleasant fashion. I held on tight gaining airspeed until the downwind wing began flying, got in behind the tug, and continued the flight.

Sunny later told be he was about to give me the rope and I thanked him to no end that he didn't.
- Danny's flying weight is 235 pounds.

- Dennis gives Neal a heart-felt thank you for not making a good decision in the interest of his safety.

- Danny thanks Sunny to no end for not making a good decision in the interest of his safety.

- Danny knows he's definitely royally screwed if his 130 pound Greenspot blows. Dennis knows he's probably gonna be dead - à la Brad Anderson and Eric Aasletten - if his 130 pound Greenspot blows.

- Dennis doesn't know this while his glider's standing on its tail? Bullshit.

- Dennis doesn't know this while he's writing this report and analysis for the USHGA magazine? Bullshit.

The reasons that a single mention of the term "weak link" is so conspicuously absent in this article are because...

- This fatality:
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.
...and this near fatality:
Soon after lift-off the trike tug and I were hit by the mother of all thermals. 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. By the time we gained about sixty 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.
...make ABSOLUTE and TOTAL ROT out of this moronic statement:
Aerotowing is clearly in this category as the tug needs to maintain a minimum speed to prevent stalling. Weak links very clearly will provide protection from excessive angles of attack, high bank turns and the like for this form of towing.
...in his moronic book and completely undermine the foundation:
A weak link is the focal point of a safe towing system.
...of everything in it - cover to cover.

- It's long since past the time at which it's permissible to publish anything negative about light weak links in USHGA's official rag anyway.
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Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Towing Aloft

Post by Tad Eareckson »

And watch this chronology.

Dave Broyles goes almost as far back in hang glider towing as anyone.
Manned Kiting - 1974

Jack Hinson and Dave Broyles dock start on a Bennett Duo-Delta.
Harry Robb - 1975/09
Clearwater, Florida

No flight should ever be made with a knot in the tow line. Aside from the abrasion caused by the knot rubbing on itself, the tensile strength is decreased by as much as fifty percent. Lines require constant inspection - prior to the first flight of every day by every flyer. In a tournament, the Lineman Starter can inspect some portions of the line on each flight, and the Safety Inspector will inspect the entire line slowly, foot-by-foot, two or three times daily. The tow line is a life line and must be treated with utmost respect.

The tow line safety release mechanism, an essential item of safety equipment is a stainless steel hook, hinged to open and close with a spring-loaded base housing that is attached to the tow line. It is activated with a motorcycle type release handle mounted on the control bar conveniently near the normal position of the hands on the control bar for takeoff. A cable in a housing from the handle to the release mechanism activates the release of the hook holding the tow line. The safety release with the hook is mounted at the forward apex of a triangular stainless steel frame welded to the control bar. When a V safety bridle is used, a second release is mounted at the top of the control bar frame near the point of its attachment to the cross spar and keel spar.

The three most used brands - home made models are not recommended due to lack of knowledge about their strength factor - are on Bennett Delta Wing gliders, on Moyes gliders, and the more recently available Schweizer sailplane release used by David Broyles and by Jack Hinson of Dallas, Texas on their conversion control bars for hang gliders. The Schweizer is rated at 1200 pounds deformation strength, as stamped on the release hook.
What barbarians!

- A knot in a line is considered a BAD thing!
Towing Aloft - 1998/01

A common weak link in this case is a loop of 130 pound test braided fishing line or a loop of 205 leech line with an overhand knot in it to weaken it. These weak links break around 120 pounds due to the knots and effect of rings or releases.
- They're using a Lineman Starter to inspect portions of the line on EACH FLIGHT!
Towing Aloft

After every couple hundred tows, inspect the length of the rope.
- They're using a SAFETY Inspector to inspect the entire line slowly, foot by foot, TWO OR THREE TIMES DAILY!
Towing Aloft

If a rope begins to break with a degree of regularity, inspect the line and replace all splices. If the line continues to regularly break, it is time to replace it.
- They consider the towline to be a LIFE LINE and to be treated with utmost RESPECT!
Towing Aloft

As the towline wears from abrasion and UV exposure, its breaking strength diminishes. Typically pilots continue using a line until it begins to break on a regular basis at normal tow tensions. Given the general tendency by pilots to save money, it is probable that you will experience a line failure during a towing career.
- They consider the release to be an "essential item of safety equipment" when we all KNOW that...
A weak link is the focal point of a safe towing system.
...a piece of string with a knot in it is your ticket to a long and happy towing career.
- They're putting the lever on the BASETUBE instead of safely out of the way on the downtube like on the back cover of Towing Aloft.
I tried to release but my body was off centered and could not reach the release.
- They're using FAA certified sailplane releases - good for 1200 pounds - instead of bent parachute pins and chunks of old washout tubing.
But I've had it once where the pin had bent inside the barrel from excessive tow force.
Think of all the hook knives you could buy with the money you save by doing it the right way!
Dave Broyles - 1990/11
Allen, Texas

As a pilot who learned to hang glide under tow back in 1972, and who wrote a major article on towing in the May and July 1977 issues of Hang Gliding, I believe my credentials are in order for commenting on Brad Lindsay's article on towing.

Brad said in his article that it was prompted by the fatality at Hobbs. Brad left Hobbs soon after Eric Aasletten was killed. I investigated the accident and supplied the accident report on which the comments by Doug Hildreth were based. I believe the primary cause to be an invisible dust devil which pitched up Eric's glider just as he released at launch. This problem must be considered in any tow situation which has strong thermal activity, with or without associated strong winds. Unless the possible consequences of encountering such turbulence is made extremely clear, it is liable to happen again.

The North Texas Hang Gliding Association met on October 5 and discussed Lindsay's article. Between us we have a bunch of towing experience of all types. We have five tow rigs represented in the club, three private and two club owned. Two are ATOL and three are trailer rigs. We tow a lot. We came to a consensus about a number of things that directly dealt with Brad's article.

The weak link breaking strength should be between 100% and 150% of the combined weight of the glider and pilot (the gross load) being towed, but each pilot should be totally responsible for his own weak link.

First and foremost, we believe that the weak link should be weak enough to protect the glider against structural failure and weak enough so that a weak link break will not cause a dangerous reaction of the glider during the course of a normal tow, but no weaker. In the opinion of the great majority of our club members, a light weak link break is as likely to endanger the pilot as to help him.

I talked to a lot of pilots at Hobbs, and the consensus was that in the course of Eric Aasletten's accident, had a weak link break occurred instead of the manual or auto release that apparently did occur, the outcome would have been the same. Under the circumstances the one thing that would have given Eric a fighting chance to survive was to have remained on the towline.
- Dave gets it right that it's gonna happen again. Arlan Birkett and Jeremiah are gonna be killed just as instantly 'cause a bit over fifteen years after Brad Anderson and Eric Aasletten eat runway we still can't understand that a glider should only come off tow upon the decision and deliberate action of the freakin' pilot - not some stupid auto release mechanism or goddam piece of string with a knot in it.

- There's enough intelligent life in that part of the country for people to realize that light weak links can be dangerous.

- There's not enough intelligent life in that part of the country for people to realize that light weak links ARE dangerous.

- There's not enough intelligent life in that part of the country for people to realize that weak links don't help pilots.

- The business about weak links CAUSING dangerous reactions of the glider is total bullshit. You can live or die because you came off or stayed on tow and it's IMPOSSIBLE to make predictions about what's gonna happen until you know the situation. That's why you use a pilot and a release to determine on/off status and the goddam weak link ONLY for its ONLY purpose - to protect the glider from overloading.

- This is - as far as I can tell - the LAST time we're gonna see a recommendation in Hang Gliding magazine to beef up the weak link to something approaching a safe and sane rating - 1.5 Gs.
2004/06/26 14:00 - Hang Glide Chicago - Cushing Field - Sheridan, Illinois - W 5 mph, thermally
- Mike Haas - 53 - Advanced - Moyes Litesport 147
- Arlan Birkett - Kolb pilot

Highly experienced mountain pilot aerotowing a newly-purchased glider experienced a lockout at low altitude. Witness reports indicate that the glider began oscillating immediately after leaving the launch dolly. The weak link broke after the glider entered a lockout attitude.
2005/09/03 18:30 - Hang Glide Chicago - Cushing Field - Sheridan, Illinois
- Arlan Birkett - 47 - H-4, advanced tandem instructor, AT administrator
- Jeremiah Thompson - 32
North Wing T2 - over/under harnesses
http://www.chgpa.org/forums/viewtopic.php?f=2&t=988
Another HG tragedy
Paul Tjaden - 2005/09/05 23:55:24 UTC

One witness said the glider fluttered and spun to the ground from two hundred feet up like a wounded bird...
http://ozreport.com/forum/viewtopic.php?t=865
Tandem pilot and passenger death
Mike Van Kuiken - 2005/10/10 18:44:27 UTC

I watched the glider come almost straight down from about 250 feet. I saw that Jeremiah was doing the take off right from the start and I watched him get pretty low on the tow as the tug crossed the road at the end of the runway. I looked down for a few seconds and when I looked back up, they were released, and going into what looked like a whip stall. After the wing dropped they were in an almost straight down nose dive and they couldn't pull out. The weak link broke from the tow plane, I'm guessing from the increasing pressure from being that low on the tug. My personal opinion is that the glider was just being pulled through the air in a stalled position and they were trying to push out to get back into position behind the tow plane which slowed them down even more, the weak link broke, they didn't have enough airspeed to fly safely yet, and then a whip stall.
Mike Van Kuiken - 2005/10/13 19:47:26 UTC

The weak link broke from the tow plane side. The towline was found underneath the wreck, and attached to the glider by the weaklink. The glider basically fell on the towline.
Chicago Sun-Times - 2005/10/06

Family's suit seeks answers in deadly hang-gliding crash

Steve Patterson - Staff Reporter

Four weeks after a horrific hang-gliding crash killed two people in LaSalle County, one victim's family is demanding answers.

Jeremiah Thompson was killed Sept. 3 while on a tandem hang glider, learning the hobby from Arlan Birkett, owner of Sheridan-based Hang Glide Chicago.

An airplane towed the hang glider into the air, with plans to reach 3,000 feet before the cable was released and their tandem hang glide began, an attorney said.

But two hundred feet into that ascent, the cable snapped, and the hang glider plummeted to the ground, smashing to pieces and instantly killing Thompson and Birkett.

On Wednesday, Thompson's family filed a negligence lawsuit against the company, demanding unspecified damages but also hoping to find out how the crash happened.

"They're two hundred feet in the air, and while normally they would glide to the ground, this hang glider nose-dived to the ground," attorney Matthew Rundio said. "We need to find out why that happened."

Rundio is now collecting witness accounts of the crash, including a possible videotape of it happening.

Thompson's family said, in his obituary, that he died in "the last of a series of lessons" with Birkett.

Birkett, 47, had been hang gliding since 1987, according to his obituary, and was certified by the U.S. Hang Gliding Association as an advanced hang-glider pilot and as a tandem instructor.

Thompson, 32, was a Montana native who came to Chicago to work as a computer programmer at Epiphany Capital Management.

In his obituary, his family said he was a member of the U.S. ski team and was nominated as a Rhodes Scholar before graduating from Dartmouth College.
We need to find out why that happened.
We KNOW EXACTLY why that happened. We just wanna make real sure nobody else does.
Manned Kiting
The Basic Handbook of Tow Launched Hang Gliding
1974

"A bad flyer won't hurt a pin man but a bad pin man can kill a flyer." - Bill Bennett
"The greatest dangers are a rope break or a premature release." - Richard Johnson
Safety Notice

HG Tandem Aerotow Operations
Date of Notice:
2006/03/15

It was noticed over a number of years there have been a number of fatalities to participants in hang glider aerotow instruction. The president of the USHPA, therefore, formed an Ad Hoc Joint Committee of the chairs of Safety and Training, Tandem and Towing to investigate this, appointing the Chair of Safety and Training to preside. Tandem instructors, Matt Taber and David Glover were invited to participate.

This committee reviewed a number of possible causes for aerotow tandem fatalities. One particular possible cause stood out as predominate. This was the common belief that when a glider gets low on tow the pilot can safely push out and let the glider climb up to the level of the tow plane safely because the glider will not stall under tow.

This issue is so important that this committee and the towing committee have recommended that the following message be sent to all aerotow pilots and all Aero-Tug pilots with a particular emphasis to aerotow tandem pilots.

Experiences in hang glider tandem flight using aero-tow launch along with analysis of accidents and incidents that have occurred during such flight strongly suggest, for safety reasons, the following cautions be observed.

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 pass 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 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.

To insure that all AT rated tandem pilots are notified, we are asking that the AT-rated tandem pilots sign on to the USHPA web site (http://www.ushga.org) and fill out a form that states that they have read and understand the safety notice. If you are an AT-rated tandem pilot and do not have computer access (ie. no email address) you will be sent the form to fill out and sign, and a USHPA addressed, stamped envelope. Understand that we are not asking if you agree with the safety notice, but that you have read it and understand what it says. You will need to do this in order to have your tandem rating renewed.

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.

David G. Broyles, Chairman of Safety and Training Committee
Steve Kroop, Chairman of Tow Committee
Paul Voight, Chairman of Tandem Committee
Three glider pilots - a twenty year Hang Four and a one-landing-short-of-solo student with his tandem instructor - die at the same flight park in a period of one year, one month, and nine days after weak link failures.

And there is NOT ONE mention of weak links in the entire idiot advisory.
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.)
Should the tandem glider become unattached...
That's code for weak link failure. But you're not allowed to call it a weak link failure 'cause all of the USHGA scumbags on this committee - with the possible exception of Dave Broyles - have built their organization, reputations, and businesses and careers on the premise that only good things can come from weak weak link failures.

But don't worry, kids. This is mostly a tandem issue so all you solo guys will always be just fine on 130 pound Greenspot.
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Towing Aloft

Post by Tad Eareckson »

http://www.hanggliding.org/viewtopic.php?t=21897
Hang Gliding Books
Dustin George (AcTiOn!JaCksOn) - 2011/05/15 21:06:02 UTC
Front Royal, Virginia

Hello everyone. What are some good books on Hang Gliding and meteorology? I have a book called "Hang Gliding training manual" that I got from a beginner hang gliding package, it is really good. Is there anything else worth while reading? What about DvD's?

- Dustin

Working on my H2 @ Blue Sky
Tim Dyer - 2011/05/15 22:01:07 UTC
Las Vegas

Understanding the sky
also by Dennis Pagen
Dustin George - 2011/05/17 12:36:09 UTC

I will check it out. Love Pagen's Training manual so far.
Grant Bond - 2011/05/17 13:02:39 UTC
Perth

I got myself Dennis Pagen's Proformance Flying which has a few "ah ha" moments, a good read while sitting on the hill hang waiting. If it has his name on it you can't go wrong.
Yeah. How could you POSSIBLY go wrong with Dennis? And good luck with Steve Wendt too!
User avatar
Tad Eareckson
Posts: 9161
Joined: 2010/11/25 03:48:55 UTC

Re: Towing Aloft

Post by Tad Eareckson »

Hang Gliding - 1999/01

Incident Reports
by USHGA Accident Review Chairman Bill Bryden

1998/10/25 17:45 - Jamie Alexander / Frank Spears, Jr.

There are a couple of aerotowing accidents...
Accidents? I thought this discussion was gonna be about incidents.
...to report and discuss this month. The first tragically involves tow fatalities on a tandem flight. An instructor, Jamie Alexander and student pilot Frank Spears, Jr., died in the accident. We extend our thoughts and prayers to them and their families.
Yeah, we always do - frequently.
The accident occurred October 25, near Groveland, Florida.
Groveland? This wouldn't be Quest you're talking about?
It was an evening flight, approximately 5:45 PM, and was the last of numerous tandem and solo aerotow flights occurring that day.
Really? They had another forty-five minutes to go before sunset. I'm surprised they weren't able to get another ten hops off the ground before they were legally required to pack it up. Where's Davis when you really need him?
Conditions were mellow with a light two-to-five mph wind. Conditions had been stronger earlier in the day, 15 to 18 mph with gusts to 20.

The glider was equipped with tricycle landing gear consisting of castering wheels mounted to the control bar, and aft, a tailwheel assembly supporting the keel. This widely used system allows the glider to launch and land rolling on the gear, eliminating the need for a launch cart.
And a lot of broken downtubes and arms and dislocated shoulders... but I digress.
The harness was the over/under style tandem harness that is used in a number of tandem operations around the country. The 175-pound instructor was in the top harness and the 198-pound student was in the lower harness.

This was the student's tenth instructional flight and his training was progressing normally. On this flight the student was flying the glider, hands on the basetube with the instructor at the "ready" position on the downtubes. After launching and becoming airborne the glider popped up a bit high behind the tug, but the position was soon corrected.
BFD.
This suggests that the student was controlling the glider with the instructor initiating the correction either verbally or physically.

Shortly thereafter, the glider began oscillating in roll and yaw, again suggesting the student was piloting and over-controlling the glider.
It might also suggest that there were twice as many Pilots Inducing Oscillation as is the case in a solo tow.
At a point just before things went bad, the tug climbed...
Oh. Things didn't really get bad until the tug climbed. How very interesting. (Just got a weird deja vu sensation.)
...and the glider got low behind the tug.
Oh. The glider got low behind the tug. Obviously by pulling in. When what it SHOULD have been doing, of course, was pushing out to stay level with the tug. Sounds like it was a really bad idea to let this student have this much control over the flight.
At about 75 feet AGL...
Glad you clarified that. I was thinking MSL.
...one of the oscillations progressed into a left turn that quickly accelerated into a bank of approximately 80 or 90 degrees...
- Well obviously then...
Quest Air

The strength of the weak link is crucial to a safe tow. It should be weak enough so that it will break before the pressure of the towline reaches a level that compromises the handling of the glider but strong enough so that it doesn't break every time you fly into a bit of rough air. A good rule of thumb for the optimum strength is one G.
Towing Aloft - 1998/01

Weak links very clearly will provide protection from excessive angles of attack, high bank turns and the like for this form of towing.
...the problem was that they either were using a weak link WELL in excess of one G or weren't using one at all. From the pros at Quest no less. Go figure.

- Isn't that phenomenon usually referred to as a "lockout"?
...at which time the rope was released from the glider. The glider then slipped/dove into the ground impacting on the left leading edge, then nose, finally rolling over on the right leading edge and kingpost. The occupants impacted the ground with major injury to the head, neck, back and internal organs of both. Frank died at the site and Jamie the next morning at the hospital.
Angelo Mantas - 2005/08/30

The glider continued rotating left and dove into the ground, first hitting the left wing tip, then nose. The glider's pitch was near vertical on impact, confirmed by the fact that the control bar, except for a bend in one downtube, was basically intact, whereas the keel and one leading edge snapped just behind the nose plate junction. Mike suffered a broken spinal cord and was probably killed instantly.
This just happens over and over and over! What have we gotta do to get people to use properly applied weak links? The solution is SO SIMPLE! I repeat... Where's Davis when you really need him? Or, failing that, Bobby?
INVESTIGATOR COMMENTS
WHAT investigator? And what was his relationship with the tug driver? (Assuming he wasn't the tug driver.) And what was his relationship with Quest?
While there may have been a wind gradient at about 75 feet, it is not believed that the conditions were a main contributing factor. In the investigator's opinion, the student was probably allowed to fly the glider too much at the critical time near the ground.
- Sounds to me a lot more like the goddam tug driver was allowed to fly the Dragonfly too much at the critical time near the ground - à la Gates Field 1996/07/25 and Hang Glide Chicago 2005/04 and 2005/09/03.

- By the way... How come we don't have a name on the goddam tug driver?
With the student having more body mass and possibly being stronger, and being in the lower harness position which affords more control and leverage, it is possible that the student's control efforts overpowered the instructor's.
Yeah, I'll bet it was that stupid oaf of a student who overpowered Jamie and forced the glider to get low behind the tug while Jamie was doing everything he could to push out and climb into proper position.
Earlier in the day the student had flown with an instructor who outweighed him and likely would have remembered the amount of control effort required then, which would be excessive with the much lighter instructor.
And I'm guessing that the instructor had no experience in dampening out the control inputs to get them back to something a little smoother.
OTHER INCIDENTS

Given the vast number of aerotows that take place each year and the tremendous growth of this towing method, the small number of accidents...
The ones that are so spectacular that the flight parks have a hard time covering them up anyway...
...does bode quite favorably for the safety of aerotowing. However, we have seen a few other aerotowing incidents this year as follows.

A student who had completed numerous tandem flights and extensive training hill instruction with an experienced instructor in radio contact. Soon after clearing the launch dolly, the glider began a gentle left turn and the instructor commanded more right input via the radio. This corrected the problem, but as soon as the pilot ceased correction the glider again began turning left. Instructions for corrective action were radioed but the turn progressed and the instructor commanded "release." The weak link broke. The glider continued turning left and impacted on the left wing. The pilot suffered a mid-back vertebral fracture requiring surgery.
- How odd. I've always understood that the weak link will break before you can get into too much trouble. OH, RIGHT! It did! Maybe we should spend more time discussing how much trouble you can get into AFTER the weak link breaks.

- What's going on with the glider such that it requires constant right input to prevent it from locking out to the left?
A student pilot was making his 13th solo aerotow and expressed a high degree of concern about it being number 13. The pilot launched, cleared the launch dolly and began a left turn. Observers commented that there was absolutely no input from the pilot to correct. The turn progressed and the tug pilot released the towline.
Sounds like a bad move to me. The tug driver should never release the glider if it's not in much trouble and the weak link will break before the glider can get into too much trouble. Therefore we KNOW that this glider wasn't in much trouble at the time he was released.
The glider continued turning, making almost a full 180-degree turn with no discernible pilot correction, impacting on the left wing and injuring the pilot.
Same glider?
It is not known why the pilot failed to initiate proper correction but there is suspicion that a previous medical condition may have been a factor.
Triskaidekaphobia maybe? The "pilot" had already visualized what would inevitably happen to him on this flight and - big surprise - things unfolded exactly as he was expecting them to?
DISCUSSION

As we have seen with previous aerotowing incidents, the launch and initial climbout are intensely critical. Over the years, numerous lockouts and similar events have occurred while aerotowing, at altitude, but these were basically non-events since the glider and tug separated and both continued flying with no adverse consequences.
And thus we can treat them as non-events, talk about our sterling safety records, and keep telling people that we have backup releases, weak links, and hook knives that will keep them safe and feeding them lies about releases within easy reach.
However, problems encountered during the first hundred feet of tow can produce extreme consequences.
No shit.
We cannot stress enough the need for both glider and tug pilots to exercise the utmost caution and respect for the first 200 feet of a tow -- any kind of tow for that matter. Situational awareness is critical. In the opinion of the fatal accident investigator (and I concur), we need to teach more about situational awareness.
- To which pilots? Glider or tug?

- BULLSHIT.

-- Incident 1

The student just had no idea how critical the launch was which is why he thought it would be OK to experiment with exaggerated control inputs - and the instructor was preoccupied thinking about the Hail Mary pass on the final play of last night's Dolphins/Cowboys game?

-- Incident 2

IF ONLY someone had taken the time to emphasize that a glider must be flown by a pilot once in a while during an aerotow launch.

-- Incident 3

Obviously that student should've been told just how deadly that first hundred feet could be so he would've been less resigned to the outcome predetermined by the number Thirteen.
When aerotowing this means that, especially during the first several hundred feet of the tow (the most critical), the pilot should have a plan in mind for exactly what he would do for any category of problem.
- If you're:
-- stalling, pull in
-- oscillating, fly the glider straight
-- locking out, try to go the other way
-- locked out, let go of the basetube and try to hit the lever without spinning it around the downtube then blow a good-bye kiss to your ass

- When your primary release malfunctions and your backup is overloaded pretend you have enough time for your hook knife to be of some more practical function than for the recovery crew to cut your body loose from the wreckage.

That about cover it?

Oops, forgot this one...

http://www.hanggliding.org/viewtopic.php?t=14230
pro tow set-up
Ryan Voight - 2009/11/03 05:24:31 UTC

Have you never pondered what you would do in a situation where you CAN'T LET GO to release? I'd purposefully break the weaklink, as described above. Instant hands free release Image
Thanks, Ryan.
He must know exactly where he is and what plan he would immediately implement should a problem occur.
http://groups.yahoo.com/group/skysailingtowing/message/6726
Weaklinks
Peter Birren - 2008/10/27 23:41:49 UTC

Imagine if you will, just coming off the cart and center punching a thermal which takes you instantly straight up while the tug is still on the ground.
If he's too stupid to use ribbons along the runway he should think about what he's gonna do if he center punches a thermal which takes him straight up while the tug is still on the ground. But if he hits the thermal off center a bit there's probably not a whole lot of point in knowing where he is and trying to implement some sort of "plan".
Know what happens?
Yeah, Peter, I actually do.
VERY high towline forces and an over-the-top lockout. You'll have both hands on the basetube pulling it well past your knees but the glider doesn't come down and still the weaklink doesn't break (.8G).
http://www.hanggliding.org/viewtopic.php?t=14230
pro tow set-up
Ryan Voight - 2009/11/03 05:24:31 UTC

It works best in a lockout situation... if you're banked away from the tug and have the bar back by your belly button... let it out. Glider will pitch up, break weaklink, and you fly away.
Just let the bar out a little, break the weak link, and you fly away - just like the head off an ax handle.
So you pull whatever release you have but the one hand still on the basetube isn't enough to hold the nose down and you pop up and over into an unplanned semi-loop. Been there, done that... at maybe 200 feet agl.
And if he's too stupid to have ribbons up along the runway it's a no brainer that he's also too stupid to have a release actuator on his basetube - so he should plan on popping up and over into an unplanned semi-loop and pulling out of it before he slams in and breaks his stupid fucking neck.
For example, a common type of problem is to suddenly lose tow force. This could be due to a release malfunction, pilot error, a weak link break, or whatever.
OH! A weak link break can be an actual PROBLEM? Get out of here! Sounds like more of this crappy argument that being on tow is somehow safer than being off tow.

What's that it says in Towing Aloft?
"It is infinitely better to have a weak link break too soon rather than too late."
-- Towing Proverb
You should read it sometime. There's some really useful stuff in there.
The pilot should know exactly which way to go and how he will land in those situations BEFORE the event potentially transpires. Altitude is minimal and you simply do not have the time for much evaluation and decision-making after the problem occurs. What if the tug suddenly loses power? What is the plan to land from 100 feet? Which way will the tug pilot turn and the glider pilot turn so they do not collide while scrambling to effect safe landings? Until what altitude does the pilot just continue forward and land versus trying to turn and land?
- The tug's gonna hafta land where it has to land and the glider's gonna hafta not fly into the tug.

- How is this relevant to any of the incidents on which you just reported?

- Is this scenario common and problematic enough to be worth talking about - given all the real life deadly shit on which we should be focusing?
Situational awareness is the process of mentally going through "what if" scenarios and knowing exactly what you would do for any given problem, at any given altitude, during every single flight.
- Incident 1

If you lock out low - release, pull in, and wait to die. If you're flying tandem try to use the other person's body to cushion the impact enough so that you don't die until the next morning.

- Incident 2

If you notice the tug not turning to the left you should also not turn to the left.

- Incident 3

If you notice the tug not turning to the right you should also not turn to the right.

Failing that you should fly and land the glider after separation instead of not flying and not landing the glider after separation.
As we saw with this tandem accident and others, at low altitudes instructors must take over control of the glider at the first sign of improper flying by the student.
Unlike Jamie who was just hanging there the whole time, waiting to see what would happen next, and doing NOTHING.
This was the student's tenth instructional flight and his training was progressing normally.
This was the student's tenth instructional flight and his training was progressing normally. Normally the student's flying from the bottom position at this point. Normally students make small mistakes and get the opportunity to fix them without the goddam instructor taking over control of the glider at the first sign of improper flying. This is how students learn to take off and fly.
At a point just before things went bad, the tug climbed...
THINGS DIDN'T GO BAD UNTIL THE GODDAM TUG CLIMBED. AND YOU'RE NOT TALKING ABOUT THE GODDAM TUG AND ITS RESPONSIBILITY FOR WHAT HAPPENED NEXT.
Allowing students too much opportunity to "fix" problems at low altitude risks getting into a situation in which the low altitude does not permit recovery. When near the ground your methods must be as close to 100% as possible, and giving too much control and correction responsibility to students can seriously compromise that.
Bill, you'd hafta work your ass off for the next two hundred years just to make it up to the level of off the scale stupid.
While more data is needed to draw firm conclusions...
Yeah, if you have total shit for brains. Otherwise you can just use common sense and don't need any data whatsoever.
...it appears that there may be a correlation between a glider getting low behind a tug and bad things happening.
Listen real carefully this time, douchebag...

GLIDERS DO NOT GET LOW BEHIND TUGS. TUGS GET HIGH IN FRONT OF GLIDERS.

Read what you said:
At a point just before things went bad, the tug climbed...
- THE TUG CLIMBED. The tug's the one with the engine. The tug's the one who determines how high he is in relation to the glider. Yeah, a thermal can temporarily blast him up above the glider but that wasn't the case with this driver or the one who killed Bill and Mike and the one who's gonna kill Arlan and Jeremiah.

- If the goddam tug DOES climb the ONLY safe option the glider has is to pull in and get and stay fast and low.
There have been similarities in several incidents in which the glider got low...
...TUG GOT HIGH...
...and similar problems and consequences have occurred.

When low behind a tug, a glider risks entering the prop wash and wing tip vortices from the tug. This turbulence can be difficult to counter.
Yeah. That's why you can't have total idiots flying tugs and and not understanding that they've got other lives dependent upon their actions.
In addition, the pilot is typically flying slower, maybe even pushing out and control may be significantly diminished because of the low airspeed.
Dave Farkas - 1996/08/02

I was checking the glider in the mirror as we climbed out and it appeared a little low, but not way off. Mike seemed pushed out, but not all the way.
So if they're typically flying slower, maybe even pushing out, how come we've gotta keep listening to this lunatic crap about gliders getting low behind tugs from you morons?
Being yawed or rolled are potential events which compound the control issues already facing the pilot.
No shit.
This heightens the importance for a pilot, and when flying tandem for the instructor, to be especially intolerant of positional errors behind the tug.
What about the goddam tug driver? How come we're not talking about HIS positional error? 'Cause in hang gliding it's just so much more convenient to lay all the blame on the dead guys?
However, if the glider does get low...
This is the fifth time you've talked about the glider being low while totally ignoring the issue of why it's in that relative position.
...what should the pilot do? Pulling in aggressively and releasing is one option that deserves more consideration and that is probably under-utilized.
What's the other option, Bill? Trusting that the idiot who just outclimbed you will suddenly evolve into a competent pilot and start doing his job?
Conventional wisdom...
Right. You can use those two words consecutively in hang gliding.
...in some parts of the country recommends that if you are low behind the tug you should push out -- push out as much as desired because the glider can't stall.
Hang Gliding - 1997/05

Aerotowing
LEARNING HOW TO DO IT -- LEARNING HOW TO OPTIMIZE IT
by Austin Scott Collins, USHGA Aerotow Pilot
photos courtesy Wallaby Ranch

Your hang glider will fly at an artificially high angle of attack while under aerotow. It is virtually impossible to stall while being towed. If you push out you will not stall, you will only climb. If you get low (if the tug's wheels are above the horizon) you may have to push out hard to get back up. Do not be afraid to do this. You will climb, not stall.
Yeah, you assholes publish this crap in the NATIONAL MAGAZINE nineteen months before before Jamie and Frank are killed (less than twenty-two miles from Wallaby - speaking of "some parts of the country") and then have the gall to talk about "conventional wisdom"? Does USHGA have anybody with an IQ of 25 or better who can vet anything? Or is Tracy the best you can do?

And a zillion times more unbelievable... You assholes published this crap in the national magazine NINE MONTHS *AFTER* Bill and Mike are killed.
Aerotowing operations in other parts of the country eschew this advice, which involves hazards at low altitude as we'll discuss.
But USHGA lets everyone teach whatever the hell he wants 'cause the only safety issue it's really concerned with is making sure all its pilots can do no-steppers inside of fifty foot spots so they can land in narrow dry riverbeds with large rocks strewn all over the place and fields filled with seven foot high corn.
It is not known if the pilots in the tandem accident mentioned above were aggressively pushing out, trying to climb back up to the tug. However, it is reasonably certain that this is what happened in a fatal aerotowing accident a couple of years ago.
It wasn't quite a couple of years ago - it was seventeen months before this stupid "accident" report of yours.
Luen Miller - 1996/10

We have two more fatalities because of a glider that couldn't be released from tow.
Great job:
- getting good information out to the pilot community.
- condemning the Wallaby article in no uncertain terms.
There are a couple of fundamental issues when a pilot pushes out aggressively in an attempt to climb up to a tug. From physics...
Physics? Since when does USHGA do physics?
...we know that to increase a glider's climb rate, the force taking it upward (lift) must be increased. Basic aerodynamics states that if lift is increased, drag will increase. More drag means the towline tension will increase. If you remember last month's discussion about weak links, we discussed briefly how aerotowing employs a reasonably constant speed, the tug's airspeed, and consequently line tension varies dramatically in response to pilot input, wind, thermals, etc. So, when aero-towing, if a pilot pushes out he will increase line tension. This increases the potential for breaking the weak link.
Yeah. Especially since none of you shitheads knows what a weak link is and you always try to get it as close as possible to normal smooth air tow tension without considering the fact that the line tension varies dramatically in response to pilot input, wind, thermals, etc. and the possibility of any downsides WHEN the goddam thing blows when any of this crap is going on.
Remember that this does not occur with most surface-based towing employing tension-control systems. With these systems the speed of the tow system (vehicle speed, winch speed, etc.) will change dramatically in response to pilot input, wind, etc., and weak links will generally not break.
A weak link is the focal point of a safe towing system.
And thus your primary defense against lockouts is almost completely useless and the safety of your towing system has no focal point. You really oughta outlaw tension controlled surface based towing.
When towing -- any form of towing -- if a weak link breaks or release occurs at high tension, the glider may stall if the pilot does not instantly pull the bar in, changing the nose-high attitude (position relative to the horizon) of the glider to an attitude and consequently an angle of attack normal for free flight. Failure to promptly perform this can result in a stall similar to a whip stall.
- Whereas if a weak link break or release occurs at LOW tension, there's no possibility of the glider stalling if the pilot does not instantly pull the bar in.

- Just like there's no possibility of the glider stalling if the pilot does not instantly pull the bar in when he's free flying.

- Just like there's no possibility of the glider stalling if the pilot DOES instantly pull the bar in under any circumstances.

- And OBVIOUSLY if the pitch attitude is low the angle of attack will also be plenty low enough for normal free flight.

- Who ever heard of a glider with its nose down plummeting in a whipstall to a fatal impact?

- But even if you fail to stuff the bar promptly the resulting stall will only be SIMILAR to a whipstall. It can't actually BE a whipstall so your chances will be a little better.

- Did you READ what you just WROTE about Jamie and Frank? They blew tow at below weak link and probably not that much over normal tension and you don't think there was two pairs of hands instantly stuffing the bar for all they were worth all the way to five feet before impact? What do you think they could have done better after the onset of the lockout?

- Asshole.
So, pushing out increases aerotow line tension and increases the probability of a weak link break.
And ya know what DECREASES the probability of a weak link break? A heavier weak link. But...
Towing Aloft - 1998/01

In any case, remember: aerotowing requires a much lighter weak link than surface towing.
It's REQUIRED. It's IN THE BOOK. So what are ya gonna do?
In addition, the pilot must remember to immediately and aggressively pull the nose of the glider down to avoid a potential stall after a sudden loss of high tow tension. At altitude these are minor issues. However, at fifty feet above the ground the risks should be obvious.
http://www.chgpa.org/forums/viewtopic.php?f=2&t=3648
Oh no! more on weak links
Carlos Weill - 2008/11/30 19:24:09 UTC

The tug weak link broke off at 1000ft, in less than a second the glider was at 500ft.
A second hazard with the "push out" advice is that the glider actually can stall in some unique situations.
But, of course, NEVER in normal situations.
Recall that near the ground there can be significant wind gradients. These may be as much as 10 mph or more above just 50 to 75 feet. Tow operations generally commence into the wind, so a tug that is substantially higher than a glider may be in significantly stronger winds. If the tug flies slowly, the lower glider could stall if the pilot pushes out aggressively.
Yes. So why is the goddam tug higher than the glider at fifty to seventy-five feet?
Gliders with higher stall speeds, such as a heavily loaded tandem glider, might stall if the pilot pushes out.
- Does a heavily loaded tandem glider stall at a higher speed than a heavily loaded solo glider?
- ANY glider can stall:
-- if the pilot:
--- pushes out
--- doesn't push out
-- with the bar stuffed
Dennis Pagen - 2005/01

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 sixty 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. I cleared the buildings, but came very close to the ground at the bottom of the wingover. I leveled out and landed.
See that, Bill? His normally loaded solo glider gets hit, he stuffs the bar, he has to terminate the tow with his shitrigged release, he goes down like a brick with the bar stuffed before lucking out and leveling off at ten feet.
Remember, stalls are associated with angle of attack. It is true that in a glider angle of attack relates to airspeed, hence stalls in a glider relate to airspeed.
No. Angle of attack doesn't RELATE to airspeed - angle of attack TRANSLATES to airspeed. You know the angle of attack, you know the airspeed.
However, when a glider is under tow the rules change, since it has power pulling it through the air and stalls can occur at higher airspeeds with extreme angles of attack.

Because of the above-mentioned risks, many aerotow operations instruct students to NOT push out.
But perish the thought that USHGA should standardize procedures based on physics 'cause opinion is the only thing that keeps gliders airborne in the first place.
If low, pilots should ease the bar out to trim position but not push out past trim.
'Cause as long as that bar's no farther out than trim position there's just no possible way you can stall if you lose the tow.
The vast majority of the time, easing the bar out is all a pilot ever needs to do.
Yeah, let's gear our procedures - as well as our equipment - for what happens the vast majority of the time.
The tug pilots are similarly instructed to always come down to a low glider.
- Really?

http://www.chgpa.org/forums/viewtopic.php?f=2&t=2467
weak links
Jim Rooney - 2007/08/01 13:47:23 UTC

Whatever's going on back there, I can fix it by giving you the rope.
I thought all these assholes were instructed by other assholes that there's no problem going on back there that can't be fixed by "giving" the glider the rope.

- Somehow the drivers for Bill and Mike, Jamie and Frank, T.B., and Arlan and Jeremiah don't seem to have gotten the word.
I have found through empirical tests (done at high altitude) -- and a highly experienced instructor with over 3,000 tandem aerotows confirms -- that there are situations in which no amount of push-out will bring the glider back up to the tug.
Really. You geniuses figured out that a mostly stalled glider tends not to climb even when you try to stall it a little more?
The only remedy is releasing or having the tug pilot speed up and come down to the glider.
How many of those remedies are routinely survivable below three hundred feet?
Interestingly, some aerotow operations also instruct students to fly a little high behind the tug if they want the tug to slow down a bit and climb more aggressively.
You actually found signs of mildly intelligent life at aerotow operations? Which ones?

Any chance we could extend that to the flip side? Any chance some aerotow operations could also instruct students to fly a little fast and low behind the tug when they want the dumb sonuvabitch to dive, speed up, and start doing his fuckin' job so they don't hafta risk stalling to compensate for his incompetence?

Don't you think mention of the flip side is pretty conspicuously absent from this discussion?
The glider follows the tug, but in a sense, the tug also follows the glider. This places more responsibility and the need for glider awareness on the tug pilot, but generally results in easier lower-anxiety tows for the glider pilot.
That sentence needs some work. Lemme fix it for you...

This places more responsibility and the need for glider awareness on the tug driver - WHERE IN SHOULD BE 'CAUSE YOU'RE PAYING THIS ASSHOLE TO DO A JOB - *AND* ALWAYS results in easier, lower-anxiety, safer, more efficient tows for the glider pilot.
Some pilots will criticize this admonishment about the push-out advice and point to their record of success with it.
NO. PILOTS don't criticize this approach - just asshole tug drivers and flight park operators.
Indeed, they probably have been successful.
Sure - if you measure success the way flight parks do by counting five hundred foot plummets as successful tows when the glider has enough starting altitude to survive and only count the kills as temporary setbacks.
In addition, debate is healthy for the sport and I welcome it...
No you don't - motherfucker. When you get called on something that you can't answer without revealing yourself to be the idiot you are you just slink away from the conversation 'cause you know the vast majority of the clones who constitute this sport will let you get away with it.
...since I always learn from a good disagreement and discussion.
- Sure you do, Bill. You learn that if six different flight parks have twelve different opinions on which way is up you include all of them in different chapters of your book to make EVERYBODY happy.

- There's NOTHING in this game that needs DEBATING. This is all Newtonian physics and the debating is only done by people who don't and usually can't understanding it.
However, operations that preach against pushing out if low can point to remarkable success.
And Russian roulette players average remarkable first round success records. A bit over 83 percent.
And there are two pilots (not the ones above), I know in my heart might well be alive if they had shunned the push-out advice.
- Bill Bennett and Mike Del Signore.
- This game has gotta be about brains - not hearts. It's out of your league.
- WOULD be alive.
- It had very little to do with advice and a lot to do with instinctive response and an expectation of tug driver competence.
- How dead would they be if Dave Farkas had gotten the goddam tug down to where it was supposed to be?
Incident data clearly indicate that the first 200 feet of tow are most critical.
You mean the higher off the surface the glider is the less likely it is to smash into it? Yeah, for some reason I can't quite nail down that seems to be the trend in several aviation disciplines.
Pilots and tug pilots must have predetermined emergency plans and pilots must know exactly what their best option is for the most likely incidents during the tow and flight.
How 'bout this idea... Don't do anything stupid under two hundred feet 'cause the options for survival that low may not be all that great no matter what you plan to do before the glider starts flying again.

And note that if you're taking off with no ribbons and wheels and using a Quallaby and/or Bailey Release and...
For aerotowing operations, a weak link breaking strength equal to 80 to 100% of the total flying weight--the weight of the pilot and glider--is a reasonable starting point.
...a weak link that breaks between 80 and 100 percent of your total flying weight you've already done four or five stupid things before you've put the glider on the cart.

And when you hook up behind an asshole driving the tug you've done another but that's one that's pretty universal so ya just gotta hope that that factor only comes into play during someone else's tow - preferably Davis's.
Tandem instructors must be exceptionally vigilant and intolerant of even minor student control errors during the first 200 feet, aggressively correcting these.
Right.

If you're a Wallaby instructor and your student is low and just easing out to trim...
...you may have to push out hard to get back up. Do not be afraid to do this. You will climb, not stall.
If you're a Quest instructor and your student is starting to oscillate as a consequence of his roll corrections then just correct them more aggressively.
Tug pilots must be trained and instructed to promptly come down to low gliders...
- Didn't you just tell us that they're already instructed to do that?

- If they're clueless enough to outclimb the glider to begin with, how well does that bode for the expectation that they're gonna come back down?
...whose pilots should not aggressively push out.

These are words of advice familiar to many ears around the country. Unfortunately there are some ears that haven't heard this advice. Please share it with them.
Why not just have them read your book?
Towing Aloft - 1998/01

The words of wisdom regarding pitch control: "use whatever it takes to stay in position."
Yep. Use whatever it takes to stay in position. And don't worry about getting killed in the process.
Towing Aloft - 1998/01

Correcting Vertical Position Under Tow

- It is primarily the hang glider pilot's responsibility to remain in the correct position in relation to the tug. To do this, concentrate on the tug and maintain the proper relation to the horizon. Also feel the tow pressure and anticipate the changes.

- If you are too high or the pressure increases, pull in rapidly to dive. Stop the dive before you reach the ideal position by easing the bar out. Anticipate the possibility of overshooting; meet the tug at the horizon.

- If you are too low or the pressure decreases, let the bar out and anticipate the overshooting effect by pulling back in before you reach the ideal position. When you let the bar out to climb, it will be much further forward with a two-point bridle than in free flight. You will then often find the glider doesn't react right away, especially if you are in the down wash. Be patient and maintain minimum controllable flying speed for roll corrections.

- It is better to be a bit too high than too low.
It is primarily the hang glider pilot's responsibility to remain in the correct position in relation to the tug.
- The primary responsibility of both drivers is to protect their own planes.
- The secondary responsibility of both drivers is to not endanger the other plane.
- It's more the tug's responsibility to not endanger the glider than it is the glider's responsibility to not endanger the tug 'cause...
-- It's a LOT easier for the tug to kill the glider than it is for the glider to kill the tug.
-- The tug pilot is also acting as a copilot of the glider and managing the degree and alignment of its thrust.
-- The tug is typically being paid to do the job.
-- The tug typically has a zillion times more tow experience than the glider.
-- The tug's the plane with the engine.
-- If the tug's a Dragonfly he's got a zillion times the control authority of the glider.
-- The tug is ALWAYS better off without the glider and the glider is almost always worse off - occasionally dead - without the tug.
Two things you can't use in aviation: altitude above you and runway behind you.
- It's always possible for any plane to go down. In fact it's a one hundred percent certainty that it eventually WILL.
- It's never possible for a glider to go up very much without help.
- It's a lot harder for a tug to go up than down.
- Thus the responsibility to keep the planes level ALWAYS rests with the high one.
Also feel the tow pressure and anticipate the changes.
Right - PRESSURE.
If you are too low or the pressure decreases...
- YOU are NEVER too low. The problem is that the tug's too high and/or slow 'cause there's an idiot driving it.
...let the bar out...
- If you let the bar out...
-- you're:
--- reducing your already crappy control authority
--- greatly increasing your ever present vulnerability to a lockout
--- setting yourself up for a stall and making yourself extremely dependent upon sustained tow tension
--- trying to do the tug driver's job for him
--- sending a signal to an idiot that he's doing fine and doesn't need to adjust his speed and altitude
-- aforementioned idiot is likely to respond to the compliment you just sent him by getting even higher and slower

- DO NOT - repeat - DO NOT EVER let the bar out to try to compensate for a high and/or slow tug. Pull in, pull his tail down, let him know that he's either gotta start doing his job or cut you loose or you're gonna stall his ass.

Asterisks...

The above assumes that the planes aren't getting blown up and down by thermals and sink. So yeah, if the tug rockets up in front of you and you have good speed then climb a bit. But don't go nuts 'cause you'll be blasted up yourself in another five seconds - by which time the tug will be back in sink.

Et cetera.
When you let the bar out to climb, it will be much further forward with a two-point bridle than in free flight.
Bullshit. If the glider's trimmed properly the positioning of the basetube with respect to the pilot will be about the same. Because of the mostly forward tension the glider will be pitched up more - but so will you.
You will then often find the glider doesn't react right away, especially if you are in the down wash.
- If you're low and slow in the downwash with the glider not reacting you might wanna consider just how much it's worth it to you to "let the bar out to 'climb'" and attempt to continue the tow.

- As a matter of fact you shoulda done that a long time before you got in that situation.

- And exactly how did you get in that situation anyway? Maybe it's time to open up a new can of tug drivers.
Be patient and maintain minimum controllable flying speed for roll corrections.
- Yeah. Do that. And always maintain the faith that:
-- the weak links at both ends will hold;
-- the Rotax won't start conforming to Murphy's Law;
-- the tug driver won't make a good decision in the interest of your safety; and
-- Mother Nature won't throw in a little something extra just to make things a little more interesting.

- And if you're friends with the tug driver don't worry about his career or reputation. You can rest assured that the USHGA report - if they bother to publish it at all - will protect his identity and spend half a dozen paragraphs talking all about how the glider got low on the tug.
It is better to be a bit too high than too low.
- But it's also cool to be low and slow in the downwash with an unresponsive glider and the bar let out and patiently wait to climb.

http://ozreport.com/8.190
Hang Glide Chicago
Davis Straub - 2004/09/16

Arlan wanted me to keep the wheels of the Kolb a plane height above the horizon.
- Except at Hang Glide Chicago.
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