2016/04/03 Tres Pinos fatality

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34243
Fatal HG crash in Tres Pinos CA 4-3-2016

Rick Maddy - 2016/04/16 04:50:06 UTC

Michael Grisham - 2016/04/15 19:28:57 UTC

The problem with scooter towing for the new student is the repetitious nose high attitude takeoff practice becomes an ingrained habit. Ten years later the student will be on a cliff launch and the nose high attitude will be so ingrained it will take continuous conscious effort to keep the nose down, an un-natural act.

If this is an issue...

It's not. It's obviously something this douchebag pulled outta his ass.

...then it is due to poor scooter towing instruction.

It would also require a graduating student to be fundamentally incompetent.

When I came back into this sport back in '07 I re-earned my H2 primarily through scooter towing. The first day was mostly relearning how to ground handle and practice ground runs with a proper nose angle, balance, etc.

And anyone who can do that has got a pretty good feel about how to fly a hang glider.

And then every single scooter tow (from only getting 10' off the ground on up to getting 500' off the ground) started with a proper nose angle that would be appropriate for any foot launch.

Ex fuckin' zactly.

Any bad launch started with the nose too high was either aborted if needed or the tow operator got you into the air (safely) anyway. Either way, you got a good talking to about the bad, nose-too-high launch.

The glider itself is pretty good at giving you feedback on those issues.

When taught properly, no student comes away from scooter towing with any bad habit of launching with the nose too high.

They save that for the stunt landing.

Especially when combined with the occasional training hill days where proper nose angle for the given slope is reinforced.

So you're saying it's an obvious common sense thing?

2016/04/16 08:52:47 UTC - 3 thumbs up - Don Arsenault

Erik Boehm - 2016/04/16 09:12:57 UTC

Back to tow line force, running to the side, etc.
As long as the force is being transmitted directly to the center of gravity...

Where's the center of gravity? The pilot's part of this equation and he's a pendulum. How 'bout talking about the center of lift instead?

...it won't exert any torque, although it will change your velocity vector (i.e. running to the side, the hangstrap will pull the glider to the side you're running, but it won't change the bank).

It bloody well WILL. If you run to the side the glider WILL bank - the way you don't want it to.

This same concept applies to the space shuttle... the main engines on that had a 20 degree gimbal range to keep the center of thrust pointing at the center of mass (which moved considerably as the "belly" mounted external tank emptied, and the solid boosters burned). Initially, the main engines actually impart quite a large lateral force, without changin the orientation.

I don't think this is particularly relevant. We're not talking about a wing generating lift and they roll the plane belly up shortly after they clear the pad.

Whether its rocket thrust, force from a hangstrap, or force from a tow line, force through the center of mass does not impart any torque.

The center of mass is about two thirds of the way down the suspension from the wing to the pilot. If you apply a lateral pull it WILL roll the glider - in the opposite direction.

Without touching the control bar, you can't exert torque. I've heard this run toward the low side a lot... but as people here have said, in my experience it doesn't work and you have to run while pulling yourself ot the lowside with the controlbar.

Really amazing how much total rot in hang gliding one hears all the fuckin' time about stuff that works...

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

Jim Rooney - 2011/08/25 21:40:25 UTC

Anyway...
Weaklink material... exactly what Davis said.

It's no mystery.
It's only a mystery why people choose to reinvent the wheel when we've got a proven system that works.

...and actually doesn't - and usually does the precise opposite - ain't it, Erik?

A tow line is a bit more complicated, because past a certain angle, it may exert a force on the control bar... as you see at at about 1:45 here, where its pulling the basetube down.

http://vimeo.com/68791399
http://vimeo.com/68791399

096-14515
http://farm9.staticflickr.com/8629/16673939502_08b58b0ffa_o.png


Note that you can barely see where the towline's running at 1:45. It's running down a bit for of the line defined by the port sidewire - with LOOKS LIKE it's the towline.

As to this video... it seems to me that at between 0:25...

15-02429
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...to 0:29...

22-02829
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...line pressure was released...

So that it stops pushing the glider backwards.

...as you see a lot more curvature in the line...

Bullshit. He's also flying increasingly towards perpendicular to the tow so of course you're gonna see more line curve.

http://www.youtube.com/watch?v=4pkB7GIxTUU
http://www.youtube.com/watch?v=4pkB7GIxTUU

coupled with a decreased attitude.

Wouldn't you expect to see more nose up on a glider heading towards the pull than on one flying away from it?

By 0:35...

32-03504
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...he's not moving closer to the tow source, indicating that the line isn't still being reeled in.

Ya think?

Still without the line actually cut, there will be tension, especially as he's turning away from the tow source rather than towards it.

But WITH the line cut there will be zero issues related to the line being dragged across the ground and through the corn. Granted, it may not be a significant factor, but it sure was when Shane Smith's cut towline end snagged at the pulley.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34243
Fatal HG crash in Tres Pinos CA 4-3-2016

Brad Barkley - 2016/04/16 12:51:30 UTC

One new thing I noticed about the video from Lin Lyons, on re-watch: he actually signaled the tow operator to back off the power by taking his legs out of the harness and scissoring them back-and-forth. And still they kept towing him. Just complete ineptitude by the tow operator. SMH.

http://vimeo.com/68791399
06-15-13 hang gliding tow release fail with parachute deployment

Lin Lyons - 2013/06/20 18:38 UTC

By 1:30 in, I know I'm in trouble. I kicked my feet out of the harness to indicate that I had a problem. (But they already knew that.)

At the top of my flight, I was dragging about a mile of tow line behind me. Harold had released the power to both winch drums, and watched the line scream off both drums at a rate he'd never seen, or heard, before. He was pretty much terrified.

Great job doing your homework, Brad. Also using your common sense to assume that the winch guy was totally oblivious and/or clueless as to what was going on with the glider and what he needed to be doing.

Übermensch - 2016/04/16 14:00:02 UTC

"Later, Harold, the tow operator, said that the towline was screaming off both the drums at an absolutely frightening rate."

-Lin Lyons, October 2013, Hang Gliding & Paragliding, Vol. 43, Iss. 10

http://issuu.com/us_hang_gliding_paragliding/docs/hgpg1310_issuu

In other words, that means without a doubt that they did cut the line tension.

Personally, I can't tell what the tow operator is doing by looking at the line in a crappy YouTube video...not in Lin's video...not in the video of cornfield-lockout pilot...probably not in most any video...it's much better to rely on real accounts from real people who were really there.

It would be really nice if the motherfuckers on the front ends of some of these fiascos and disasters would come out from under their rocks and tell us what was going on.

2016/04/16 17:29:57 UTC - 3 thumbs up - Dave Jacob

Brian Scharp - 2016/04/16 14:31:19 UTC

Erik Boehm - 2016/04/16 09:12:57 UTC

Back to tow line force, running to the side, etc.
As long as the force is being transmitted directly to the center of gravity, it won't exert any torque, although it will change your velocity vector (ie running to the side, the hangstrap will pull the glider to the side you're running, but it won't change the bank).

Not in the intended direction anyway. Can anyone post video evidence of roll control with no hands, in particular leveling a banking wing by running towards the high side?

A video unlike one has ever seen before. Nobel Prize material.

I'll concede that moving your body into position using your legs is easier than relying solely on torque to get there, but it's the holding yourself in that position (applying leverage on the control frame) that provides the torque to affect the desired change.

Just pay Ryan to produce the video and shut the fuck up.

piano_man - 2016/04/16 14:43:28 UTC

Erik, did you mean run toward the high side?

That's the side Ryan's running toward.

Erik Boehm - 2016/04/16 09:12:57 UTC

I've heard this run toward the low side a lot... but as people here have said, in my experience it doesn't work and you have to run while pulling yourself ot the lowside with the controlbar.

Any thoughts on:

As to this video... it seems to me that at between 0:25 to 0:29, line pressure was released...

NMERider - 2016/04/16 16:11:02 UTC

The line should have been cut free with a guillotine...

Steve Davy - 2013/09/06 01:07:07 UTC

I talked with Pat about Lin's little adventure and what's been done to avoid a repeat.

When asked if a guillotine had been installed he expressed that he didn't like/trust the added complexity. And that his fix was to go with a two string that can't be configured incorrectly.

...or other cutting implement. Even assuming the published statement is factual and not merely a self-serving afterthought, those drums...

Can anybody figure out why we're talking about drumS?

...have resistance that keeps tension on the line and the glider is locked out in an unrecoverable dive. Failure to immediately sever the line is a serious error that could have killed the pilot. Of course the pilot should have also had a cutting implement (hook knife) in easy reach.

It's 44 seconds between Lin's first attempt to release the three-string with which he fucked up the connection and the silk popping. It's 43 seconds between Todd...

http://www.youtube.com/watch?v=mJGUJO5BjnA
http://www.youtube.com/watch?v=mJGUJO5BjnA

...attempting to blow his very very reliable bent pin barrel release that just failed because it's a mechanical thing and him finishing cutting himself free. At twice the altitude with the glider under reasonable control and the situation nowhere approaching critical and probably not particularly dangerous. I think he would've been able to spiral down with a slack towline still connected. Fuck hook knives.

BTW - Welcome to the Org I see you account is new. Why not tell us something about yourself in a separate, introduction post?

Übermensch - 2016/04/16 17:29:16 UTC

I'm glad that you assume that the statement is factual.

In addition to any resistance from the drums or any other part of the system...there is also the weight of the lines, the wind forces acting on them, etc.

Even assuming the tow operator cuts the power, the tension/pressure, and the lines themselves...if the tow line(s) are still attached to the pilot--through the control frame--then recovery is...challenging?...unlikely?...impossible? (I can only be certain that it's a situation I would not want to be faced with.)

Of course the pilot should have also had a cutting implement (hook knife) in easy reach.

Absolutely. (Though I sure wouldn't want to have to try and cut several lines when there are only seconds left...YIKES!!!)

"Eleven seconds of parachute time is WAY TOO SHORT. When I'm in trouble, I need to decide much earlier that I am in trouble, and toss the chute. A couple more seconds in my 35mph dive would likely have eliminated that parachute time completely."

—Lin Lyons, October 2013, Hang Gliding & Paragliding, Vol. 43, Iss. 10

Still...

"During my descent, the towline broke....The video seemed to indicate that it chafed on the pipe clamp that held my wheel in place....It was a good thing that the line broke, because one of the roads was well traveled, and some car would surely have run through it, giving me a good tug."

—ibid

Even more reasons to have a hook knife handy.

That's OK, Über. I'm capable of rigging releases to make the probability of my being able to separate from tow 100.000 percent. And if you don't think you can do that it would me smarter to install Linknives on all the components you're afraid you might need to cut away.

Scary stuff...all of it...but...gotta keep thinking about it and talking about it and preparing ourselves for it...and encouraging others to do the same.

Bullshit. Hearing about some bozo unable to separate himself from a tow with the crap equipment he's elected to use instead of the bulletproof stuff we've bent over backwards to make available to these douchebags while getting pissed all over for our efforts scares me about as much as hearing about some other bozo who's guzzled himself into a stupor and lost a curve at a hundred miles per hour.

NMERider - 2016/04/16 17:55:16 UTC

Exactly, Friedrich!



Hook knives save lives. Ask any law enforcement officer, EMT, fire fighter, search and rescue person.

You'll have to. Because if you ask hang glider pilots you won't get any actual examples.

For a hang glider pilot or tow operator that hook knife needs to be readily accessible...

If a hang glider pilot can't free himself with his readily accessible release how much good do you think a readily accessible hook knife is gonna do him? 'Specially considering that just about all serious tow incidents are precipitated from well under two hundred feet?

If a hook knife is considered to be a must for the other end of the rope then how do you justify not having a proper guillotine?

http://www.youtube.com/watch?v=ifQk5L3Ux7U
http://www.youtube.com/watch?v=ifQk5L3Ux7U
http://www.tost.de/bilder/SEK%20Endstueck%20S%2010.jpg


You think you'll need to cut the towline to save somebody's life but an extra ten seconds in the equation won't really make enough difference to worry about. "Dude. There's a rabid Grizzly out there. Better take this buck knife along with you just in case."

...and not merely something that's tucked away just because it's standard equipment. How many reserve toss clinics include grabbing the hook knife while in mock-danger?

Fuck reserve toss clinics. Time machine. Do we send Lin to a reserve toss clinic or a three-string release clinic?

What's the ratio of how-to-land-in-a-narrow-dry-riverbed-with-large-rocks-strewn-all-over-the-place clinics to how-to-not-land-in-a-narrow-dry-riverbed-with-large-rocks-strewn-all-over-the-place clinics?

How many times to we not only reach for our reserve handle with either hand during flight but also reach for our hook knives so it becomes automatic?

I dunno. I wasted all my time developing tow equipment that eliminated the need for reaching to releases, hook knives, and reserve handles.

Not only do we need to be able to deploy our reserves without pondering it--we may later need to be able to cut away from our reserves before they become our undoing.

How much flying have you done relative to your average weekender and how many times have you needed to reach for a hook knife or reserve handle? And how many times have you gotten hurt and how many of those incidents would've been mitigated by a hook knife or parachute (rather than caused by one of the latter)?

There was a near-tragedy very recently in which a pilot may have easily drowned after landing in surf. The time he spent trying to disconnect his carabiner could have possibly been shortened by having a hook knife readily available where it was instinct to grab it. Had sand from the surf jammed the biner this pilot may have been our next statistic.

So he was using a locked locking carabiner and flying in range of surf? Darwin comes to immediate mind.

I use this to illustrate the value of a readily-accessible hook knife that we don't have to think about to use.

'Cause there aren't any good illustrations of the value of a readily-accessible hook knife that we don't have to think about to use for towing situations.

Yeah. Have a hook knife readily accessible for going down in surf if you're flying where that's a possibility. Just don't delude yourself into thinking that it'll greatly increase your chances for survival.

Hook knives in towing systems are just crutches and excuses for using crappy tow equipment. In other words... If you think there's a 0.001 percent chance that a hook knife will be of some use on a tow then stay the fuck on the ground. THAT's compatible with the excellent article by Mike Meier, "Why Can't We Get a Handle On This Safety Thing?" that everybody keeps re-reading while the bloodbath continues and the sport slides further along the way to oblivion.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34243
Fatal HG crash in Tres Pinos CA 4-3-2016

JJ Coté - 2016/04/16 23:30:51 UTC

Lateral force applied through the CG can't exert torque, but on a glider with a floating crossbar (i.e. any modern glider), it can move the keel to one side. The effect of the resulting "billow shift" is left an an exercise for the reader.

2016/04/17 01:31:01 UTC - 1 thumb up - Rob McKenzie

http://www.kitestrings.org/post9296.html#p9296
launching

Steve Davy - 2016/04/17 08:05:58 UTC

I agree. Watch the keel pocket shift 0:09 to 0:10.

http://www.youtube.com/watch?v=sk1IfUFyJas
http://www.youtube.com/watch?v=sk1IfUFyJas

OK...

05-0907
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07-0921
http://c2.staticflickr.com/2/1457/25820928943_252bcd5acb_o.png


Pretty close. But let's do:

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06-0911
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instead - widely separated and out of order though they may be.

- The first shows the glider in a shallow coordinated bank with the suspension fully loaded and centered - no roll control / lateral torque effort being applied, everything symmetrical.

- The second is the first of several frames depicting max torque to correct the roll to starboard. We can see:

-- the asymmetry of the white keel pocket from the camera mounted below the keel and thus shooting up at a shallow angle

-- the starboard side of the keel pocket 'cause it's moving towards being mashed against the port side undersurface

-- 8.6 percent more sail "depth" at the port edge of frame (pixel count - 265:244) than we can at the starboard due to the billow shift due to offset loading due to Ryan moving to port and torqueing the control frame lever arm to starboard

Now to simplify all that - 'cause all this is really simple...

- In the top frame everything below the sail is, of course, perpendicular to it, centered, collinear

- in the bottom frame everything below the sail - keel pocket, keel, hang strap, carabiner, harness suspension, harness, pilot - is angled to port but still collinear

In other words the keel pocket is just an upward extension of the hang strap. For the purpose of control the wing doesn't know or give a flying fuck about the structure of what's below it. All it knows and cares about is what it's feeling and supporting through the stitching just both sides of center securing the keel pocket to the wing. The load of the pilot and whatever Gs he's pulling is distributed by the stitching but the force is a vector at the hang POINT. And the control frame, which is braced in position by the flying wires, gives the pilot the means to offset his weight / torque the glider around his mass.

The cross spars were originally bolted to the keel 'cause that LOOKED LIKE that was how the job should be done. Then I think based on:

http://www.hanggliding.org/viewtopic.php?t=31498
Richard Boone

we got the "floating crossbar" from Dick Boone.



The crossbar / cross spars didn't float. The keel floated with respect to the wing. It just looked like the cross spars pair was floating when you were standing at hook-in position.

The (poorly thought out) idea was that the extended keel pocket would facilitate / enhance billow shift. It did ABSOLUTELY NOTHING in that regard. It was well intentioned total snake oil. The only good thing that came out of it was that it serendipitously removed the cross spars connection to the keel which never should've existed in the first place.

At some point Wills Wing figured this out by looking at film from a keel mounted camera showing just what we see here in Ryan's video and glider's evolved accordingly. But the myth persists. And it's contrary to the interests of the hang gliding industry for the recreational pilot to have any real understanding of how his wing works so here we still are.

[Steve Davy]

In other words the keel pocket is just an upward extension of the hang strap.

I had never considered it like that before. Now I'm going to have to go and think about this some more.

[Tad Eareckson]

Hate to tell you how much time I've had to think about this shit to get my head wrapped around it.

http://www.hanggliding.org/viewtopic.php?t=34243
Fatal HG crash in Tres Pinos CA 4-3-2016

Ryan Voight - 2016/04/17 04:48:42 UTC

Reading all these comments...

Yeah, you're reading all THOSE comments over THERE. You're not reading all THESE comments over HERE.

(I thought we were past the "run toward the lifting side" thing on this thread?)...

Fuck running to sides. I never incorporated these clever little sayings into my wiring. I just instinctively reacted to what was going on with the wing just as I would in full flight. I think you'll find that to be the case with anyone who has any business flying these things.

I *think*, just maybe, I understand our disconnect!

No.

We are all correct

Logically impossible on several levels.

The statement:
"CHANGE YOUR DIRECTION OF RUN MORE TOWARD THE LIFTING WING" is a cue; a simple descriptive direction.

Thanks, I don't need it. And I doubt that any students do or benefit from it. If you turned them loose on sand dunes with no instruction whatsoever I seriously doubt they'd be doing the opposite of what they needed to in order to get airborne.

Taken quite literally, in the video I posted of me launching at Ellenville, I should be running a diagonal path to the left of the center of the launch. I was not.

You didn't need and may not have been able to.

If the glider is banked/rolled/rolling to the right, it's going to be a challenge just to keep running along the straight path of original intent.

A tiny fraction of the challenge it's gonna be for you to produce a video of you or anyone else roll controlling a glider by running to the high side without using your hands.

Someone earlier mentioned running the curved path the turning glider is following-

Steve Corbin - 2016/04/14 19:04:52 UTC. Do your homework.

...and that is what my teaching cue is meant to avoid.

One of my own teaching cues is for people to avoid your teaching cues. Although I could say, "Ignore his teaching cues and watch what he actually does." 'Cause there's nothing wrong with your actual flying.

Running to the left OF THE NEW, CURVED PATH... is essentially leaning into the glider and actually pulling along that same straight path as originally intended.

Bullshit. If you lean left into the glider without torqueing the bar you're gonna power plant your right tip. I one hundred percent guarantee you that you won't have any problem whatsoever producing a video to illustrate THAT phenomenon. I don't think I can find an existing video to illustrate that point because I don't think that - even in hang gliding - there's anybody out there stupid enough to have actually done it.

Also, just briefly touching on the whole torque/what makes a glider turn thing... I'll try to be kind...

It's your ass that's in need of kindness now. As you write you make it quite clear and openly state that you don't at least fully understand how this works. Yet you still have the arrogance and stupidity to say that you'll "try to be kind" to the opposition.

...and say that I find it most unlikely that our gliders turn because of the minimal rolling torque pressures...

1. Torque isn't a pressure. It's a push or a pull on a lever arm and it's measured in foot pounds - not pounds per square inch.

2. If these "minimal rolling torque pressures" are so fucking minimal why do we have VG systems on our gliders? Why don't they ship with sail tension fixed in the configuration of full VG? When we fly VG loose all we're doing is significantly degrading our performance for no good reason.

Looks like your launching and flying here:

12-02223
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with VG off. And here:

13-02306
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as you're prepping to do this:

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you're cranking it on. We can clearly see the line streaming as you're going over the top. So what's the deal on that?

...we are applying through the control frame.

1. And the wires.
2. Do you also find it most unlikely that we're roasting the planet by adding a tiny percentage of carbon dioxide into the atmosphere?

I will also present evidence of that silliness- Follow the forces!

Produce the video, motherfucker. All ya gotta do is run your next landing accordingly with the GoPro on your keel still running.

To move your weight left, you are pushing the base bar to the right. The base bar isn't able to go to the right, primarily because of the left side wire.

Bull fucking shit. You weigh two or three times what the glider does and the whole fuckin' glider will move around you more than you will move in relation to it.

Tension on that wire might be increased...

1. MIGHT BE?

2. Or pressure might be increased on that sidewire...

Ryan Voight - 2016/04/15 13:28:18 UTC

After reading that description- do you guys see what I see, did I miss something that lead you to say the tow pressure was released?

Like what happens on the glider end of the line when you pressurize the front end of the line.

3. If tension on that wire MIGHT BE increased what MIGHT BE going on with the tension on the other wire?

...but the cross-bar/leading-edge junction isn't pulled toward the corner bracket...

Yes, it is - asshole. Along with the rest of that half of the glider. (Note here that being pulled toward doesn't necessarily mean being moved toward. You can put a collar and leash on an elephant and pull him toward you all day without making any progress - but he's not gonna be unaware of what you're doing.)

...primarily because of the upper side wire running to the kingpost.

Show me the upper sidewires running to the kingpost on your glider...

06-0911
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...and/or Jonathan's.

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Possibly tension on that is increased, but the top of the kingpost isn't able to move toward the left cross-bar/leading-edge junction because of the upper right flying wire. Keep going in your mind, until you get back to the base bar... (it's a closed system folks).

And next month, people of varying ages, we'll cover topless gliders like the one I fly. Whole different can of worms 'cause the wing is braced internally versus externally.

The kingpost and top wires are - excluding irrelevant issues like negative loading, reflex bridle, kingpost suspension - irrelevant. Just as the flying wires are slack and irrelevant on the ground ('kept for the tail wires when the glider's parked on its tail), the top (or ground) wires are slack and irrelevant in the air.

Let's look at what the longitudinal wires are doing on your kingposted closed system, Ryan...

09-03015
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Matt's obviously torqueing his control bar back to keep his glider from outclimbing the Dragonfly. Pretty good bet the nose wires are under tension 'cause otherwise the control frame would fold back and Matt would die... So how come the tail wires are so slack you could throw them away and it wouldn't matter as long as he's pulled in?

Instead, what causes a glider to roll is an imbalance in aerodynamic forces.

What is it you use to get the aerodynamic forces to imbalance? Your tongue?

When hanging centered and neutral, the center of gravity (the point at which gravity acts on the pilot/aircraft as a single combined unit) is in alignment with the center of lift. Move your body to the left...

How? Answer the question without using the word "hands".

...and now gravity is acting more on the left...

How considerate of gravity to adjust to what it is that we're doing at any particular moment.

...while lift is now acting to the right of where gravity is acting.

Bull fucking shit. You torque yourself to the left you load the left wing more, it distorts by pulling sail from the right to left wing, the trailing edge of the left wing deflects up and dumps lift while the trailing edge of the right wing is pulled tight and down and increases lift. The left wing is flying at a lower angle of attack while the right is flying at a higher angle of attack.

10-0418
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It works exactly like ailerons or the Wilbur and Orville wing warping that preceded ailerons. (Jonathan's rolling out of a turn rather than into one.)

46-3023
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YES, THAT IS ROLL TORQUE, TOO. But it's caused by aerodynamic forces, not us muscling the glider to roll around us!

Sounds like a good murder defense. "Yes, your honor. It was I who pulled the trigger but I was nowhere near her when the bullet finally slammed into her head. I've got five witnesses who can put me a quarter mile away on the other side of the river at the time."

So- back to "run toward the lifting side"...

Now that we've cleared up that misunderstanding to everyone's satisfaction - kindly.

...(hopefully for the last time?!)-

You should be so lucky.

...ignore the cue being said, and watch the video.

I wanna watch the one somebody's made of him rolling the glider without using his hands.

Watch the wing lifting away from me, and look where the hang loop moves when I lean into the harness to the left. Did my feet actually run left of launch-center? No. But I didn't drift off right of launch-center, either! Even though I am not hanging entirely suspended from the glider, it is lifting up, and I am running downhill- away from the wing (but we're connected). This *DOES* allow me to weight shift, IE shift the CG of the pilot/wing combination... and because gravity IS acting on the total unit, and because lift is acting on the total unit... shifting these forces out of alignment DOES create roll torque in the desired direction. EVEN IF I DON'T MOVE THE CG WITH MY HANDS!

Sorry Ryan. Could you go over all that again? I was busy watching what you were doing with your hands and didn't catch it.

I apologize to those that, I see now, took the CUE more literally than it was meant.

That's OK. The important thing is that you have a full understanding of all this and have been fundamentally right in everything you've said.

It works very well when teaching because...

...the average hang gliding student is a semiliterate total moron who couldn't tell you the difference between pressure and tension with a gun to his fuckin' head and three of his children already dead on the floor.

...that's exactly what it feels like you're trying to do, or even doing, even though it's pretty much impossible to actually run left of launch-center while the glider is banked and turning to the right.... So, again, sorry for the confusion.

Please don't apologize. Hang gliding would be unable to exist in its current form without confusion.

Now I might suggest any additional discussion about "run more toward the lifting wing"... or about why a weight-shift flex wing hang glider rolls when we move our ass... we should take it to another thread, yea?

Sure Ryan. We'll look for you posting a video of you or one of your students or friends correcting roll without using his hands over there. And thanks zillions for being so kind to us muppets while we muddle along trying to get good grasps on these fundamental and critical concepts - that our instructors for some reason were unable to get across to us as we were scoring our Ones, Twos, Threes, Fours.

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34243
Fatal HG crash in Tres Pinos CA 4-3-2016

Erik Boehm - 2016/04/17 11:27:03 UTC

Ryan Voight - 2016/04/17 04:48:42 UTC

Follow the forces!...

All that is completely irrelevant All you're saying is that no part moves appreicably in relation to another part.

Well said, Erik.

That means nothing with regards to the entire thing rotating.

You mean like when you apply torque via a chain to a cog at a bicycle wheel hub and it propels you forward even though no parts of the wheel move in relation to other parts of the wheel?

Instead, what causes a glider to roll is an imbalance in aerodynamic forces.

More specifically, when the aerodynamic forces are not aligned with the center of mass.

When hanging centered and neutral...

Its more of center of mass shifting, rather than "gravity acting more, but whatever.

No. Not "whatever". It's "whatever" that's gotten us where we are today.

YES, THAT IS ROLL TORQUE, TOO.

For a rigid system it would bebut without contact with the control frame, any force applied will go through the hanstrap, which should be attached basically at the CoM of the glider, in which case you haven't changed the location of the CoM... anymore than you need to account for the mass of a winch that is towing a glider line 1 mile in front of the gilder or 2 miles in front of the glider.
How is the pilot pulling through the CoM of the glider with only one strap any different from a tow line pulling the glider through one line going ot the CoM?
Its not, they don't exert any torque.

It won't exert any torque but if it pulls sideways the glider will roll trim to the new gravity vector and things won't end well unless something changes.

But it's caused by aerodynamic forces, not us muscling the glider to roll around us!

In your description, all you claim to do is move the CoM out of alignment with CoL. Its semantics to call that aerodynamic forces rather.
My understanding in contrast, is that the torque a glider experiences causes deformations of the wing, which also contributes to moving the CoL as well. Thus the CoM moves in one direction, the CoL in the other.

It's a lot easier to understand with the ailerons analogy.

In contrast, a rigid wing doesn't do this, which is why they need control surfaces. Under your explanation, a rigid wing and a flex wing would turn equally well just through moving the CoM.

So- back to "run toward the lifting side" (hopefully for the last time?!)... ...EVEN IF I DON'T MOVE THE CG WITH MY HANDS!

I'm with you up until the last line, without a rigid/semi-rigid connection via your hands, its not proper to consider it as a "total unit" for the purposes of torque.

...or about why a weight-shift flex wing hang glider rolls when we move our ass... we should take it to another thread, yea?

Yea, perhaps, want to start it or should I?

Why? This thread was started on response to an incident of a mostly nameless alleged Hang One student being killed as a consequence of the basic incompetence of her instructor. Competence doesn't even BEGIN before a classroom understanding of basic aeronautical theory. (Read some Jim Keen-Intellect Rooney posts if you believe otherwise.) First we get the theory right then we work on the nuts and bolts.

P.S. Everybody notice all the posts Steve Aeroexperiments Seibel isn't contributing? Very consistent with his mission of never adding anything to a forum or discussion of any actual practical value.

We don't really have any details to go on here...

Fuck the details. We have total shit in the way of basic facts. And that's a pretty goddam significant basic fact in and of itself. Mission boasts all over its website about what an awesome instructional program they have - even now. Don't the motherfuckers owe it to the hang gliding community to add something of instructional value to this discussion in the wake of the mess they created?

...however, to the limited extent that this discussion is relevant to the incident, we are in agreement that the tow operators shouldn't increase towline pressure to try and pull them back on course, because that's going to do nothing to correct their roll/pitch.

I beg to differ - dickhead. If they'd increased towline pressure the line would've gone slack. Couldn't have made the situation any worse.

Brian Scharp - 2016/04/18 02:08:50 UTC

I'm not seeing the conflict at the top of the kingpost.

You would, but Ryan's got one of the new see-through kingposts from Wills Wing. Make the gliders look like a toplesses but they're pretty tough on attacking hawks and eagles.

Now I might suggest any additional discussion about "run more toward the lifting wing"... or about why a weight-shift flex wing hang glider rolls when we move our ass... we should take it to another thread, yea?

http://www.hanggliding.org/viewtopic.php?p=386476#386476

http://www.hanggliding.org/viewtopic.php?t=34277
"evidence of that silliness"

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34277
"evidence of that silliness"

Brian Scharp - 2016/04/18 12:36:28 UTC

Ryan Voight - 2016/04/17 04:48:42 UTC

Also, just briefly touching on the whole torque/what makes a glider turn thing...

Can you go into more detail?

Ryan Voight - 2016/04/18 15:19:29 UTC

The question you should seek answer to- in order to understand how/why a hang glider rolls with weight shift- is actually...
How does a PARAGLIDER roll with weight shift?

Sure is a good thing they invented those things. Otherwise we'd have no fuckin' clues as to how our hang gliders work.

Think about it for a minute...

Which is the maximum length of time Ryan's ever thought about anything.

...no "rolling torque" exerted on the wing...

Not much in the way of an airframe on which to exert torque either.

...(weight shifting in the harness lowers one riser and raises the other...

Sounds familiar.

...where as weight shifting in a hang glider exerts a lateral force on the control frame...

And a downward force on the wing - idiot.

...which is what was claimed to be the source of the roll)...

And no billow shift.

It's one wing with no distinct, fixed, structural centerline like a hang glider has. There's gonna be a continuous asymmetry across the entire span.

No change in angle of attack of the inside/outside wing from increasing/decreasing wingloading...

If it's turning... there IS.

Brian Scharp - 2016/04/18 15:43:13 UTC

Sounds the same to me. More tension...

Pressure.

...on one side, less on the other. Reminds me of...

http://www.youtube.com/watch?v=LdCibXWAJ0Y
http://www.youtube.com/watch?v=LdCibXWAJ0Y

Ryan Voight - 2016/04/18 15:56:56 UTC

Erik Boehm - 2016/04/17 11:27:03 UTC

My understanding in contrast, is that the torque a glider experiences causes deformations of the wing, which also contributes to moving the CoL as well. Thus the CoM moves in one direction, the CoL in the other.
In contrast, a rigid wing doesn't do this, which is why they need control surfaces. Under your explanation, a rigid wing and a flex wing would turn equally well just through moving the CoM.

It has been believed for a long time that a hang glider wing deforms and that leads to the rolling of the wing.

It was believed for a long time that a one-size-fits-all single loop of 130 pound test precision fishing line installed on one end of a one or two point bridle that would blow six times in a row in light morning conditions was the focal point of a safe towing system and that anything heavier that would allow a reasonable expectation of making it to altitude was an inevitable death sentence for anyone foolish enough to try to reinventing the wheel.

But a newer, wiser theory exists...

Fly with whatever Davis is happy with at the moment.

....and makes much more sense (and explains a lot of other interesting nuances, as well!)

Unfortunately, due to the nature of the quantum physics involved with this newer, wiser theory, video evidence supporting it is impossible to capture with available technology.

It's now believed that a hang glider's wings do not deform to act as ailerons might on a traditional aircraft...

48-3121
http://c2.staticflickr.com/6/5825/22896853706_1f0297165b_o.png

51-3315
http://c1.staticflickr.com/1/678/22730213630_da4fe66997_o.png

56-3720
http://c1.staticflickr.com/1/763/22297052553_fd9bb656d7_o.png

61-4009
http://c2.staticflickr.com/6/5643/22918193135_92df039edc_o.png

28-115614
http://c2.staticflickr.com/6/5650/22547382390_00be87276c_o.png

...but that the deformation occurs AFTER the wing begins rolling, and is due to the changes in relative airflow on each side.

Good Ryan. We'll just add this to the Russian novel's worth of other insane moronic newer, wiser theories that find their ways into the excellent book, Towing Aloft, by Dennis Pagen and Bill Bryden, and the mainstream forums four or five times a week.

Watch a video of a hang glider turning, from behind...

I still wanna watch that video of your hang glider turning, from behind, in a desirable direction, with your hands a couple inches clear of any aluminum, carbon, stainless steel in response to you running under the high wing and shifting your weight.

...and notice the sail does not deform at the time of weight shift, but only after the wing begins to roll.

How very patient of it.

It blew my mind, too...

You really oughta see somebody about having your mind unblown before...

http://www.hanggliding.org/viewtopic.php?t=30824
Article "Pushing Out" Feb 2014 HG mag

NMERider - 2014/02/25 06:05:06 UTC

What part of:

...his rather nonsensical and too-often phantasmagorical version of physics and aerodynamics.

wasn't clear?

Ryan is a classic example of a superbly talented athlete who is ill-equipped to write a comprehensive training manual or academically meaningful text.

...writing stuff where people can read it.

Erik Boehm - 2016/04/17 11:27:03 UTC

I'm with you up until the last line, without a rigid/semi-rigid connection via your hands, its not proper to consider it as a "total unit" for the purposes of torque.

The only reason I'm using the word torque is to relate what I'm saying to what was said earlier... because it's not that I think Jonathon's explanation was balls wrong exactly, it just missed some crucial elements. I was trying to show my agreement that the glider does roll because of "torque"... and the correction is that it's not torque from our body, applied through the control frame, and literally rolling the glider around ourselves...

Which is what actually happens. It's the reason gliders have minimum certified hook-in weights.

...but it's one side lifting more while one side is pulled harder by gravity. That resultant is, technically, also a torque force, no?

1. I guess. I'm still trying to get my head wrapped around this concept of gravity pulling on the stuff we want it to pull harder on and lighter on the stuff we want it to pull lighter on.

2. Yeah. It's a torque force. Just like in a conventional fixed wing aircraft. You torque a joystick or control yoke, one aileron goes up while the other goes down, and the whole plane is torqued into (or out of) a roll. So what's your point?

In your description, all you claim to do is move the CoM out of alignment with CoL. Its semantics to call that aerodynamic forces rather.
My understanding in contrast, is that the torque a glider experiences causes deformations of the wing, which also contributes to moving the CoL as well. Thus the CoM moves in one direction, the CoL in the other.
In contrast, a rigid wing doesn't do this, which is why they need control surfaces. Under your explanation, a rigid wing and a flex wing would turn equally well just through moving the CoM.

I had the same thoughts when I first heard this new school thinking...

What new school would that be, Ryan? MIT? Wallaby? Quest? Florida Ridge? Lookout? Morningside, Cloud 9? Cowboy Up? Mission?

...and I grasped for reasons it couldn't be true. If it's true, what I grew up believing- KNOWING- everything about how our wings steer- was inaccurate!

Which, given who your father is...



...would be patently absurd.

It's very hard to let go of an old paradigm, especially when it's been widely accepted as fact for a long time!

Yeah. Usually ya gotta wait through a couple decades of carnage until some hotshot, popular, tandem aerotow instructor pro toad gets splattered in totally unambiguous circumstances for a looooong track record to end.

The answer to that line of thinking- rigid wings would also roll via weight shift alone- is that THEY DO!

A 747 will roll via weight shift alone. But it will take a while.

Buuuuuut... it gets more complicated than that... because moving the CG out of alignment with the center of lift... is also to move the CM of the aircraft. CG and CM or more or less interchangeable terms, for our purposes, even though in the physics world I do understand they have slightly different specific meanings (which are sometimes important).

Not so much in the range of Planet Earth's breathable atmosphere.

The CM of the aircraft is the point in which all axis of rotation occur (pitch, roll, yaw). In diagrams we always see the arrows drawn with the center of the wing, right around the kingpost or hang loops, as that center. But if we shift the CG, CM moves too!

Duh. They're the same fucking things within a given gravitational field. Or even out of one 'cause the glider itself has a(n insanely weak) gravitational field.

Hopefully everyone knows that, in a vacuum, a bowling ball and a feather should fall at the same rate.

They should but they won't. 'Cause the bowling ball has a greater gravitational field than the feather and will pull the Earth immeasurably faster toward it than a feather will.

In the real world I *KNOW* we all know that's not what happens. Heavy shit gets slowed down a lot less than light shit as it moves through the air, right?

Well when CM moves to one side, we have a "heavier" wing and a "lighter wing"... but equal drag on both, right?

Wrong. The heavier wing deforms under the load, the trailing edge deflects upward thus decreasing the angle of attack and thus drag and thus speeds up while the lighter wing does the proportional opposite. Hence we get adverse yaw - which Wilbur and Orville learned about the hard way before they figured out their plane needed a rudder.

The now-heavier side is able to move a little faster through the air, while the now-lighter side is slowed more... and we have yaw.

Adverse yaw. Which our swept wing cancels out. But I thought you said the wings had equal drag on them.

Now the really interesting part- because rigid wings use control surfaces rather than weight shift, they can be designed with dihedral for much greater roll stability.

Which is always a tradeoff with handling.

Hang gliders, steered purely by weight shift, can't be roll stable or moving our butts a few inches or possibly a few feet wouldn't do much... but aerodynamic control surfaces, placed well outboard on the wing, provide plenty of authority to roll a much more stable design.

And there's an interesting thing with anhedral vs dihedral...

Fuck anhedral versus dihedral. Anhedral has absolutely nothing to do with wings geometry and was co-opted by idiot pilots. The proper terms are positive and negative dihedral.

...when it comes to YAW. When a wing with dihedral yaws, the "upwind" wing presents it's bottom surface, and the resultant is roll IN THE DIRECTION OF THE YAW. Look at all the RC gliders that use *only* rudder and elevator for control... the wings have significant dihedral! Look at the spoilerons on an ATOS... I'm sure they kill the lift on one side of the wing, leading to an imbalance of forces there... but they also yaw the glider toward the intended turn direction... and the glider then rolls that way.
Now, when an aircraft has anhedral, and it yaws, the "upwind" wing is presents it's top surface, which gets pushed down rather than lifted up... and so the glider rolls OPPOSITE the yaw. Sound like anything we've flown before?

Your point relevant to the discussion being?

When I heard all this... I fought it hard in disbelief... but after thinking it through, researching, studying....
Dude... MIND

Ryan Voight - 2016/04/14 03:41:18 UTC

Wager all you want, but I've done this a lot already. I'm not making s*** up here, or speaking of something I haven't thoroughly tried out (like you are!).

I could go out to a big field, set up a glider, put a harness on, set up some cameras, and thoroughly document how I can run long distances while still keeping the glider going exactly where I want it to go...

But frankly, that sounds exhausting. And I really don't have that kind of free time in my life- to chase down something I already know and have practiced quite a bit.

I've already spent more time than I should on the .org, and on this thread specifically, in effort to share education and improve safety. I just taught you something(s) you didn't know, and your blockhead response is that I should take more time out of my life to "show you".

Dude, I'm sorry... but unless you want to come here and PAY ME TO SHOW YOU... since instruction is my job and how I feed my family after all... I'm inclined to say piss off. Why don't you go set up a glider and run around with it and, when you realize you CAN steer by changing the direction you're running, you can buy me a beer for sharing a skill with you that just might save a launch some day...

Or... you can continue to disagree. Without trying it. Funny thing is, physics doesn't really care or rely on your agreement, it just is.

So... what say you... ready to take an afternoon and go have your mind blown? Or will you choose to stay behind the keyboard talking about things you don't seem to understand fully?

Ryan Voight - 2016/04/18 16:01:25 UTC

And I will add- I did not create this theory, it was only taught to me... and so I do apologize if my explanation of it is a bit sloppy... my feeble mind can only grasp so much, ya know? But the more I explore this, the more and more it's REINFORCED- and the more other crap (like the yaw stuff ^) makes sense.

I notice you're very conspicuously not telling us who it was who created this theory. Makes it a bit difficult for us muppets to hear it first hand, don't it?

And it's a bit odd that this great new theory doesn't seem to have been published anywhere.

Lemme tell ya sumpin' 'bout THEORY - motherfucker. THEORY isn't something some douchebag CREATES. That's a HYPOTHESIS. A hypothesis becomes theory when it's shown through scientific observation, testing, experimentation to be able to explain all related phenomena and predict outcomes. And assholes unable to differentiate tension and pressure have no fuckin' business entering the discussion.

[Steve Davy]

...it distorts by pulling sail from the right to left wing, the trailing edge of the left wing deflects up and dumps lift while the trailing edge of the right wing is pulled tight and down and increases lift.

This is what I imagine happening in Ryan's video. As he YANKS the keel to port the starboard trailing edge tension increases while the port trailing edge tension decreases.

[Tad Eareckson]

Yeah, but it would be better to say and think keel POCKET than keel. We're trying to relegate the keel's role to the appropriate level of insignificance.

http://www.hanggliding.org/viewtopic.php?t=34277
"evidence of that silliness"

Brian Scharp - 2016/04/18 16:23:23 UTC

To initiate a roll in a flexwing torque needs to be applied to the control frame or connecting parts.

Yeah, well you know, that's just like your THEORY, man.

NMERider - 2016/04/18 16:26:34 UTC

Ryan Voight - 2016/04/18 15:19:29 UTC

Think about it for a minute... no "rolling torque" exerted on the wing (weight shifting in the harness lowers one riser and raises the other, where as weight shifting in a hang glider exerts a lateral force on the control frame, which is what was claimed to be the source of the roll)... And no billow shift. No change in angle of attack of the inside/outside wing from increasing/decreasing wingloading...

Wrong again. You're batting 1,000 boychick. Try consulting an expert who actually engineers the craft in question rather than relying on thought experiments.

Thought experiments were how Einstein did the Theory of Relativity. Depends a lot on who's doing the thinking.

Dave Pendzick - 2016/04/18 16:33:25 UTC

In a vacuum, like the moon, a feather & hammer will fall at the same rate. Here on earth, heavy shit falls faster. I have witnessed this in skydiving many times.

Amazing.

I am a little confused about several things.

Anything a good video wouldn't put to rest?

I understand how a paraglider / parachutist can roll the wing about its longitudinal axis...

As opposed to rolling the wing around its latitudinal axis.

...with using weight shift only as I have done this many times myself. I am confused by the theory that a hang glider turns because the billowing sail on the heavy side acts as an aileron causing the turn.

Don't ailerons usually come in pairs and work in opposition?

This was how my instructor explained it to me.

Figures.

The part I am confused about is if that were true, wouldn't the outboard wing, or wing opposite the turn, also billow as the result of increased airspeed?

The wing doesn't billow because of airspeed. It billows because of increased and asymmetrical loading. The billow decreases the angle of attack / increases the airspeed and you need sweep or rudder to counter the adverse yaw.

Correct me if I am wrong...

Again?

...but the outboard wing has to fly faster through the air than the inboard wing.

Yes.

This would cause increased lift...

No. Just because it HAS TO doesn't mean it DOES. It's flying at a higher angle of attack, generating increased lift, climbing so it's flying SLOWER. You hafta DO SOMETHING to MAKE it fly faster.

...& a billow in the sail as well would it not?

It would - and DOES - not. It's the asymmetrical LOADING that causes increased billow on the heavier side and decreased billow on the lighter side.

Therefore, I am in agreement with Ryan that the movement of the CG is more of a causal force for rotational moment about the longitudinal axis of the aircraft vs billow in the sail on the heavy wing acting as an aileron.

And if Ryan thought he was in trouble before...

Is that the gyst of this thread or am I off in left field?

You're so far off in left field that you're in the bowling alley - and your spelling of "gist" isn't helping matters.

Brian Scharp - 2016/04/18 16:39:05 UTC

How do you initiate the roll?

Run to the side you want down - while carefully not touching anything with your hands and making sure you're not being filmed.

Dave Pendzick - 2016/04/18 17:00:50 UTC

The rolling, or rotation about the longitudinal axis, happens due to the change in CG. Airplanes have fuel tanks in their wings, what do you think will happen if I were to suck fuel from one side only?

You'd roll to the other side. But that's not what's happening with the hang glider - idiot - cause all the relevant weight is hanging from a point on the centerline. And the only way you can offset that weight to asymmetrically load your wings is to PUSH/PULL yourself to one side USING YOUR HANDS.

Ryan Voight - 2016/04/18 17:13:55 UTC

NMERider - 2016/04/18 16:26:34 UTC

Wrong again...

I can not tell you how much I love this response Jono. You provide no conflicting reasoning why this newer theory might be incorrect...

Not happy? Try over here.

...you just spout off that I'm not adequately qualified.

Which is so fuckin' obvious as to be totally unnecessary.

Where do you think I learned this newer theory?

Wow. I've been repeatedly asking that very same question myself.

#irony

Dave Pendzick - 2016/04/18 17:00:50 UTC

The rolling, or rotation about the longitudinal axis, happens due to the change in CG. Airplanes have fuel tanks in their wings, what do you think will happen if I were to suck fuel from one side only?

Exactly, great example Dave.

Boy did you just fuck yourself over but good.

It's not because we're pushing laterally on the control frame and exerting a roll torque... although that's kind of a bass ackwards...

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

Jim Rooney - 2013/02/12 18:00:27 UTC

I get tired as hell "refuting" all these mouth release and "strong link" arguments. Dig through the forums if you want that. I've been doing it for years but unfortunately the peddlers are religious in their beliefs so they find justification any way they can to "prove" their stuff. This is known as "Confirmation Bias"... seeking data to support your theory... it's back-asswards.

Toldyaso, Jim Keen-Intellect Rooney.

...way of saying it's because we shift the CG... since it's one-and-the-same... it's just the focus is on the method of CG movement as the cause of the resulting roll... rather than the CG movement itself causing the roll.

Moron.

My head is starting to hurt... I'll check back later, need a break for a bit... lots to do today still...

Produce the video?

Fun conversation though!

Wouldn't be if I were able to participate over there.

Brian Scharp - 2016/04/18 17:16:15 UTC

Airplanes use ailerons to roll. In a flexwing I move my weight over by pushing/pulling (torque) on the control frame.

You THINK that's what you're doing. But you're NOT.

Ryan Voight - 2016/04/18 17:26:43 UTC

(see my post above- I was probably adding that response to Dave as you posted this)

See? Toldyaso.

Dave Pendzick - 2016/04/18 17:41:20 UTC

The control frame of the hang glider is not a steering wheel by which you turn the glider, it is merely a tool by which you use to shift your weight from one side to the other hereby changing the CG of the aircraft which causes the roll.

Right. It's a steering wheel - with somewhat crappy mechanical advantage.

Dave Pendzick - 2016/04/18 17:44:04 UTC

That being said, it is somewhat of a steering wheel / gigantic yoke stick on a rigid wing hang glider.

Progress.

Brian Scharp - 2016/04/18 18:11:30 UTC

Right. Show me evidence you can achieve flexwing roll control without using that tool.

His opinion is good enough for me - asshole.

Dave Pendzick - 2016/04/18 18:37:20 UTC

I'm not sure I understand the point of the question. Roll authority would be lost without the use of the control frame. I agree I guess. How this is applicable I do not know...

Then shut up and go away.

Brian Scharp - 2016/04/18 19:02:39 UTC

http://www.hanggliding.org/viewtopic.php?t=27217
Bad Launch!

Ryan Voight - 2012/09/26 14:23:55 UTC

Running to the right = weight shift to the right.

It's all about what the glider feels. Running to the right pulls the hang loop to the right, just like when you weight shift at 3,000 ft. Glider doesn't know or care what means you used to pull the hang loop to the right.

Brian Scharp - 2016/04/18 19:23:03 UTC

Ryan Voight - 2016/04/14 20:49:27 UTC

I think you don't understand the word TELLING, and mistook it for showing?

One can be DONE and the other can't?

What? Are you doubting his word? His integrity?

Dave Pendzick - 2016/04/18 19:32:18 UTC

Running to the right would equal weight shift to the right provided the hang strap is loaded. If the hang strap is not loaded & one is running, say on a hot day in no wind conditions, it really would not matter which direction you ran the glider will not respond until enough airspeed is obtained to provide enough lift to load the hang strap. This is why it is imperative we start a launch with level wings!!!

You need two things, airspeed & a loaded hang strap to steer the glider. You get both of those things from running.

Total fucking moron. You can fly, steer the glider all fuckin' day standing on the beach with a twelve mile per hour breeze without a harness, let alone a hang strap connection, just gripping the downtubes. How can anybody who's been around hang gliders for more than ten minutes be that clueless? How can he say this crap on a major hang gliding forum and not get the shit kicked outta him?

[Tad Eareckson]

http://www.hanggliding.org/viewtopic.php?t=34277
"evidence of that silliness"

Rolla Manning - 2016/04/18 20:08:00 UTC

What seems to be lost in the discussion is the fact that the wing has not yet generated enough lift to carry the full payload of its weight plus the pilots weight.

Who the fuck cares? What difference does it make?

If the pilots weight is off center from the Center of lift of the wing and it is trying to lift that weight it will center over that weight as it increases lift to carry it.

Fuckin' hang glider is roll unstable. That means that if everything is balanced to begin with you can expect it to stay stable hands off...

051-20014
http://c2.staticflickr.com/2/1483/26349644531_e0bbe6fd69_o.png


...for a while. But if things AREN'T balanced in roll...

069-25104
http://c2.staticflickr.com/2/1572/26142964830_289bc3f2cb_o.png


...and you stop torqueing the bar to counter WITH YOUR HANDS you can bet the fuckin' farm that things will go south FAST. This is why all the Voighters are so reluctant to put anything on film.

Whether you use the control bar or you run left or right you are still shifting the weight that needs to be lifted by the wing.

And this stupid motherfucker is a Boeing Business Jet...

http://upload.wikimedia.org/wikipedia/commons/5/5b/Boeing%27s_commercial_aircraft_in_BBJ_livery.jpg


...Captain.

(edit) I guess you beat me to it Dave.
.

Yeah. Maybe he could be a Boeing Business Jet Captain too. (Think I'll stick to surface transportation from now on.)

Dave Pendzick - 2016/04/18 20:10:29 UTC

I just went & read NME's description of torque & the analogy regarding the single line kite. So is it weight shift or is it torque or is it both?

Try neither, Dave.

http://www.hanggliding.org/viewtopic.php?t=34243
Fatal HG crash in Tres Pinos CA 4-3-2016

NMERider - 2016/04/14 20:40:18 UTC

A stable single line kite will follow the lateral force transmitted through the kite string. An unstable single-line kite such and an Indonesian fighting kite is controlled by letting the line go slack and then pulling on the line at the precise moment that the wobbling kite is pointed in the desired direction. This same effect may apply to a hang glider that is being kited hands-off.

Try going to Wikipedia and reading up on how fighting kites are designed, trimmed, and flown to get them to do what their pilots want them to. Short version... Not particularly relevant to what we do in free flight foot launching, towing, flying hang gliders.

Also read up a bit on what these cutting strings do to people, birds, bats, other living things.

So if I were to run with the glider & once it began to lift off I let go of the control frame. Lets say for the sake of argument the left wing began to raise. Would simply running towards the lifting wing without touching the control frame help? I believe it would NOT.

I can think of a really good way to find out. This issue was first brought up 2016/04/13 18:08:33 UTC - close to six days ago - on the "Worlds largest Hang Gliding community", there have been to date 129 subsequent posts over two threads and receiving thousands of hits and not one individual totally or partially on board with the Voight Theory of Hang Glider control has been able to be bothered enough to find out what happens with roll control while running a glider hands off.

But why? Would pulling on the down tube of the lifting side induce a yawing moment opposite the direction of the lifting wing?

How did we get to YAWING? To yaw a glider on the ground you'd hafta torque the bar fore and aft on opposite sides around the glider's vertical axis. This is something everybody does with the wing not flying or flying in a breeze while maneuvering to launch position but certifiably insane during a launch run.

We have pretty much zilch yaw control authority during launch and in full flight and we make the glider go the direction we want it to with a combination of roll and pitch control.

Is it the torque applied about the longitudinal axis...

Weren't you just talking about the VERTICAL axis?

...by manipulating the control frame the reason the turn is corrected? This is a very interesting discussion.

Discussions in which total morons are afforded participation and courtesy are ALWAYS very interesting - just not very productive.

2016/04/19 12:26:01 UTC - 1 thumb up -- Christopher LeFay

Brian Scharp - 2016/04/18 20:14:00 UTC

Dave Pendzick - 2016/04/18 19:32:18 UTC

Running to the right would equal weight shift to the right provided the hang strap is loaded...

If you can bring down a lifting wing by running towards it and not touching the control frame or wires, get it on film.

Oh c'mon, Brian. Let's have another couple weeks of Jack Show assholes presenting their pet theories on what SHOULD happen in reality.

2016/04/19 12:26:15 UTC - 2 thumbs up - Christopher LeFay

Rolla Manning - 2016/04/18 20:15:00 UTC

Does the kite have a floating crossbar?

No.

Brian Scharp - 2016/04/18 20:39:22 UTC

Dave Pendzick - 2016/04/18 20:10:29 UTC

Would pulling on the down tube of the lifting side induce a yawing moment opposite the direction of the lifting wing?

While rolling the wing will yaw towards the rising wing.

http://www.aeroexperiments.org/exslipturn.shtml
::Aero-Experiments::

Steve Seibel - 2007/08/06

I found that as I was rolling my glider into a left bank, the yaw string deflected toward the right. This showed that the nose of the glider was yawing to the right in relation to the actual direction of the flight path and airflow (relative wind) at any given moment. In other words, the glider was slipping. The amount of deflection of the yaw string--i.e. the amount of sideslip--was strongly related to the roll rate. The faster I rolled the glider into the turn, the more the yaw string deflected to the side. I saw roughly the same amount of deflection of the yaw string--i.e. roughly the same amount of sideslip--regardless of whether I moved the control bar far enough to hold the airspeed constant as I rolled the glider into the turn, or I made no movement of the control bar in the fore-and-aft-direction (which caused the flight path to curve downward and the nose to drop and the airspeed to rise), or I pulled the control bar in as I rolled the glider into the turn (which caused the flight path to curve sharply downward and the nose to drop sharply and the airspeed to rise rapidly).

Is it the torque applied about the longitudinal axis by manipulating the control frame the reason the turn is corrected?

Yes.

Yeah, well you know, that's just like your OPINION, man.

Steve Seibel. Last Jack and Davis Show posts: 2016/01/15 15:56:49 UTC and 2016/03/18 18:10:45 UTC respectively. Very unlikely that he's extinct. So where the fuck is he on this discussion? Is the problem that if he entered it he'd hafta say in no uncertain terms that a number of Jack Show Members In Good Standing are totally full 'o shit and thereby contribute something of actual substance at an actual personal price?

Brian Sharp - 2016/04/18 20:51:27 UTC

Rolla Manning - 2016/04/18 20:08:00 UTC

Whether you use the control bar or you run left or right you are still shifting the weight that needs to be lifted by the wing.

If you can bring down a lifting wing by running towards it and not touching the control frame or wires, get it on film. And I don't mean on your Mill with a hand on the stick.

2016/04/19 12:28:44 UTC - 2 thumbs up - Christopher LeFay

Rolla Manning - 2016/04/18 20:53:24 UTC

Am I confused here?

You're confused everywhere. And that's the kind way of putting it.

Are we talking about ground handling the glider into flight? Yeah thats called a running takeoff!
Or are we talking about after your feet leave the ground? Yeah thats call flying.
Two totally deferent topics don't you think.

What part of "get it on film" are you having so much trouble understanding, semiliterate motherfucker?

Brian Sharp - 2016/04/18 21:10:48 UTC

Running on the ground is how this started.

It actually started with in incompetent tow instructor slamming a student into the ground on total crap equipment.

If you can bring down a lifting wing by running towards it and not touching the control frame or wires, get it on film.

But you can add flying. If you can bring down a lifting wing without touching the control frame or wires, get that on film too.

Un fucking believable. Hang gliding culture is TOTALLY DETACHED from REALITY.

2016/04/19 12:29:32 UTC - 3 thumbs up - Christopher LeFay

Mike Lake - 2016/04/18 21:32:16 UTC

If you are running without holding onto the control frame you are simply towing the glider from the hang point with a very short tow line.

http://www.youtube.com/watch?v=uvhzoVC1UqM
Simple Progression for Teaching Hang Gliding

Ryan Voight - 2015/02/22

An excellent cue is to try to pull the glider through the air with the harness.

062-22100
http://c2.staticflickr.com/2/1676/26323471862_6318b4e1bf_o.png

And if hang gliding culture had had that degree of aeronautical competence and/or collective common sense the lower tow bridle connection would NEVER have been on the basetube and we likely wouldn't have gone through the decades of Hewett based hell that claimed its latest victim a little shy of sixteen days ago.

Any misalignment (great word that)...

Thank you.

...is the very seed of a lockout.

Bullshit. The killer "lockout"...

Jerry Forburger - 1990/10

High line tensions reduce the pilot's ability to control the glider and we all know that the killer "lockout" is caused by high towline tension.

...is caused by high towline tension. Just use a Davis Link and you won't be able to get into too much trouble.

Running towards the upwind/upward wing only serves to increase the misalignment.

If a tow pilot turns to the right and the tow vehicle turns to the left to compensate I don't think anyone would doubt that this would be an unwise manoeuvre.
Same thing, longer towline.

http://www.hanggliding.org/viewtopic.php?t=27217
Bad Launch!

Ryan Voight - 2012/09/26 14:23:55 UTC

Running to the right = weight shift to the right.

It's all about what the glider feels. Running to the right pulls the hang loop to the right, just like when you weight shift at 3,000 ft. Glider doesn't know or care what means you used to pull the hang loop to the right.

2016/04/18 22:54:25 UTC - 3 thumbs up - Brian Scharp

Wish I'd said that.

2016/04/19 12:30:25 UTC - 2 thumbs up - Christopher LeFay

Just two thumbs up. Don't wanna go totally nuts here.