[ZackC]

Tad,

That wouldn't have happened if he had been made to go through the paces doing turns around traffic cones at a hill or off of scooter tow.

Even if he had done those from the downtubes? This is exactly what they do out at Lookout (well, turning toward cones instead of around). I'm just trying to understand your position. I'd still like an answer to

Why would it matter whether students fly prone in their training if it's so easy to adjust to flying prone if they're properly trained to fly from the downtubes?

You've been critical of schools waiting before having their students fly prone.

It apparently didn't register very well for John Seward.

Because he didn't shift his weight (we're speculating).

I'd be inclined to teach students that it's differential wire tension that controls the glider and that weight shift is the way it's effected.

Do you think telling that to John would have helped him at all? The purpose of telling someone to 'lead with your feet' is to get them to effectively shift their weight, which they need to do regardless of the theory.

I think the best way to teach control inputs is what Bob said:

The simplest example is to just hang from a glider on the ground with a mirror to show the deflection of the hang straps as the pilot moves.

When I was at Lookout I effectively did just that, but it was somewhat accidental. Sometimes their equipment trailer, which contains the TV they use to play intro videos at the LZ, is stationed with the TV facing the simulator on that end of the field. I learned a great deal by hanging in the simulator, watching my reflection in the black screen, and seeing what caused my carabiner to move the most. I think seeing that is more effective than anything you could tell the student.

As for the theory...

You will be pulled / Your weight will be shifted to the left.

Which way will the glider roll?

Seems to me like if anything it would actually roll to the ri...oh. Wow. Light bulb. OK, let me see if I get this...

Last year I went to a clinic in Utah hosted by Ryan Voight. Ryan's into aerial photography and on a down day we were discussing camera mounts. He had a mount that attached to the base tube and extended out a ways in front of the pilot pointing aft. He said you didn't have to counterweight it because as far as the glider was concerned all the weight was on the base tube where the mount attached. I wasn't sure about that and Ryan isn't the most trustworthy source with regards to physics but he apparently had experimental verification that was the case so I went with it. It never occurred to me to apply that same principle to our hang points.

It's well known that if you put a heavy camera on a leading edge out near a wingtip it will cause a roll tendency. If the camera was in the same position but mounted to a beam attached to the keel at the hang point instead of the leading edge it would not (I think). If that's the case, the actual shifting of weight that occurs in a roll can't be the cause of the roll because the pilot is still attached to the same point on the glider. For a true weight shift roll to occur the hang point would have to move laterally.

I never really understood why a tow rope pulling a pilot didn't cause a control input in the direction of the pull but just went with it...now it makes a lot more sense. So much for Pagen's

When you move your body to the side, your weight increases the load on one wing and decreases it on the other wing. This makes the more heavily loaded wing move down to bank the glider.

Even if I accept that shifting weight isn't responsible for a glider's response, there are still some things I'm not clear about. The control frame is fixed to the keel...what causes the left wire in your example to tighten? What causes the slop transference? If the roll is caused entirely by wing warping, how does differential wire tension effect pitch changes (which, to my knowledge, are not caused by wing warping)?

By the way, this is the best illustration of wing warping I've come across:
http://ozreport.com/images/redheaddune/DSCF1906.JPG
I'd love to be able to capture it on video but it's not practical to mount a camera that can capture a glider's entire span.

As can be seen, this sideways force tends to pull the pilot over to the correct side to make the glider turn naturally in the proper direction.

Wow. I can't believe he said that. Regardless, we all know gliders tow better from the pilot than just the glider. Why is that?

I don't know this construction.

Neither do I. Here's the best explanation I've found:

Unlike flexes, the ATOS control frame is essentually non-structural. The control frame is just the "handle bar" for the glider. On it's carbon control frame gliders, AIR was able to incorporate the spoileron control wires into the control frame stabilization system, thus eliminating a set of wires. The ATOS still has rear wires, but the glider has 1/3 fewer wires than topless flexwings.

The stuff in the parentheses will cause the glider to yaw adversely but the sweep will take care of that problem for you.

Interestingly, spoilers create drag, so rigids that use them to roll supposedly don't suffer from adverse yaw.

At any rate, big thanks for the explanations. Even after a year you are still shattering the understanding of hang gliding concepts I've learned through instruction. Got any more bombs you haven't dropped yet?

Bob, thanks for your explanation as well. I'm getting closer.

Zack

[Bob Kuczewski]

Tad,
...
You've been critical of schools waiting before having their students fly prone.

I believe that if a student is flying in student conditions (as they should be!!), then staying upright may actually be safer since the cross controlling issue is greatly reduced and there's no transitioning to and from prone.

It apparently didn't register very well for John Seward.

Because he didn't shift his weight (we're speculating).

I'd be inclined to teach students that it's differential wire tension that controls the glider and that weight shift is the way it's effected.

Do you think telling that to John would have helped him at all? The purpose of telling someone to 'lead with your feet' is to get them to effectively shift their weight, which they need to do regardless of the theory.

I think you're right here Zack. The ability to rapidly, instinctively, and effectively shift one's weight is very important to staying alive. It has to be a natural response and not a "let's figure this out" moment in real time. There's a time for thinking things out (best done on the ground) and a time for knowing what to do instinctively (really helpful in the air).

I learned a great deal by hanging in the simulator, watching my reflection in the black screen, and seeing what caused my carabiner to move the most. I think seeing that is more effective than anything you could tell the student.

You're right. That sounds like very good training. 

Last year I went to a clinic in Utah hosted by Ryan Voight. Ryan's into aerial photography and on a down day we were discussing camera mounts. He had a mount that attached to the base tube and extended out a ways in front of the pilot pointing aft. He said you didn't have to counterweight it because as far as the glider was concerned all the weight was on the base tube where the mount attached. I wasn't sure about that and Ryan isn't the most trustworthy source with regards to physics but he apparently had experimental verification that was the case so I went with it. It never occurred to me to apply that same principle to our hang points.

If the situation was as you describe it, then Ryan was absolutely wrong (or you misunderstood what he was saying). The torque applied by a weight attached forward of the base tube does affect the glider. He may have gotten away without counter-weighting because it was relatively minor (torque is force times lever arm ... as in "foot pounds"). If the arm wasn't too long, and the weight was relatively light, it might have been unnoticeable, but that doesn't mean it was zero. More importantly, a statement like that can plant dangerous misconceptions in his student's minds.

It's well known that if you put a heavy camera on a leading edge out near a wingtip it will cause a roll tendency. If the camera was in the same position but mounted to a beam attached to the keel at the hang point instead of the leading edge it would not (I think). If that's the case, the actual shifting of weight that occurs in a roll can't be the cause of the roll because the pilot is still attached to the same point on the glider. For a true weight shift roll to occur the hang point would have to move laterally.

This doesn't sound quite right to me. I believe the camera attached to the beam from the keel will still impart a rolling torque on the glider. Also, when the pilot shifts, his hands are applying a torque to the glider through the base tube (or down tubes). That's what allows him to shift his weight in the first place. So you can't really separate the two. You may be confusing this with a tow line situation where the force is just along the line because that's the ONLY connection between the glider and the tow force.

Even if I accept that shifting weight isn't responsible for a glider's response, there are still some things I'm not clear about. The control frame is fixed to the keel...what causes the left wire in your example to tighten? What causes the slop transference? If the roll is caused entirely by wing warping, how does differential wire tension effect pitch changes (which, to my knowledge, are not caused by wing warping)?

I think weight shifting is responsible for the glider's response. I believe that shifting weight applies a torque to the glider through the pilot's hands which is rolling the glider. The interplay between the torque and the wing warping is a little more confusing, but I believe that the torque is the prime mover in this situation.

By the way, this is the best illustration of wing warping I've come across:
http://ozreport.com/images/redheaddune/DSCF1906.JPG
I'd love to be able to capture it on video but it's not practical to mount a camera that can capture a glider's entire span.

Try a "fisheye" lens. They can capture a wide span at a short distance.

Bob, thanks for your explanation as well. I'm getting closer.

It's good to get lots of different perspectives. Different people are tuned to different explanations at different times. I remember when I was getting ready to solo a Cessna 150. I was doing fine with everything but my landings were still somewhat rough. So my instructor had me go up with another instructor to see if he could figure out the problem. It turns out that I wasn't trimming the plane slow enough, so I was holding quite a bit of back pressure which made my arm movements less smooth than they should have been. So on the second touch and go, the new instructor told me to "take three big grabs" of the trim wheel when setting up. I did that, and it was like magic - smooth as silk. I soloed the next time out.

Thanks for hanging in with us here Zack.

[ZackC]

If the situation was as you describe it, then Ryan was absolutely wrong (or you misunderstood what he was saying).

He wasn't completely sure himself and it was just information he got from another source, but yes, the camera wasn't heavy and the arm not very long. Still, I think it would have less of an effect attached to the basetube then, say, extending down from the nose to the same position.

This doesn't sound quite right to me. I believe the camera attached to the beam from the keel will still impart a rolling torque on the glider.

Yes, I suppose you're right, but the effects won't be the same as the fulcrums are different, right? Not sure how they would differ.

Also, when the pilot shifts, his hands are applying a torque to the glider through the base tube (or down tubes). That's what allows him to shift his weight in the first place. So you can't really separate the two.

I get what you're saying...I'm just saying (correctly or not) the displacement of weight by itself won't cause a roll. Let's say the hang strap was perfectly rigid and holding a pilot at the same position he'd be shifting his weight to initiate a roll (with his hands off the basetube). I can see this would put some torque on the keel but the force will be far from perpendicular to the lever arm (I think) and I don't think it would do much.

Try a "fisheye" lens. They can capture a wide span at a short distance.

I use GoPros with a 170 degree FOV, but I still can't get the entire wing. I might do better putting the camera at the very end of the keel...haven't tried that as I can't do it with an aerotow dolly.

Different people are tuned to different explanations at different times.

Yes, but unlike your Cessna example, what we're discussing here isn't really all that important to actually flying. I still have no idea how wings work (let's not go there ).

Zack

[Bob Kuczewski]

Hi Zack,

I've spent a good portion of my career in the somewhat obscure field of artificial neural networks. It's basically a study and application of how we think humans think.

At this point in time, I believe that we learn most relationships through brute force experience. As we gain more experience the brain naturally tries to synthesize and generalize those relationships into rules that we can apply to new experiences. We also try to explain everything in terms of the things we already know - which is understandable since it's hard to explain things in terms of things we don't know!!

I'll give you one of my favorite examples. There was a time when the rising and setting of the sun was explained in terms of a chariot being driven across the sky. Of course we know that's not true now, but it was the only explanation based on what most people were familiar with at that time.

So to apply this to hang gliding, there are two levels at which we need to "understand" how a glider flies. The first level is purely experiential. "If I do this, then the glider will do that". It's pretty much a mapping of inputs to outputs without any real "logic" to explain it. But as time goes on, our mind (the mind that invents chariots) will try to synthesize a model of what's happening so those relationships can be generalized. As with the solar example, this model can be anything from a chariot to Newton's laws of physics. It's important to remember that both are inventions of the human mind. And at some level (and for some people) they're both just as good. In fact, for most primitive farmers, the chariot example works much better because it doesn't take several years of schooling and the invention of calculus to understand.

So our "primitive" mind just needs to be trained how to move our bodies to make the hang strap deflect and turn the glider. This can be done in a simulator or with tandem flights or with a slow progression of lots of training hill flights ... or in other creative ways. I believe that such training would have saved the pilot we've been discussing.

With regard to the physics of the camera mounting, I think I can help you with a diagram or two. Those will take a few minutes to work up, so I'll put them in a different post. You ask good questions, and I'm happy to spend some time trying to give you good answers.

Bob Kuczewski

[Bob Kuczewski]

OK, Here are some torque examples.

In this first picture, the torque applied to the bolt (through a force at the arrow) would be the same for all 3 cases (assuming rigid wrenches).

Torque_Examples_400.png (16.26 KiB) Viewed 7020 times

The only thing that matters with respect to the torque is the force applied and the distance from the center of rotation.

The same is true of the camera mounted in both of these cases (ignoring the mass of the mounting arm).

Torque_Examples_Glider_400.png (26.33 KiB) Viewed 7020 times

They would both apply the same torque to the glider (again ignoring the mass of the mounting arm). In both cases they should be compensated by a counterbalance unless it's decided that they're too small to worry about. But if it's decided that the mass of the camera mounted in the first position would require a counterbalance, then that same camera mounted in the second position would also require a counterbalance.

Additionally, since I don't know the geometry of your situation, it's important to remember that the torque on the mounting arm is also proportional to the horizontal displacement of the camera from the mounting point. So in this example, the lower mounting arm would have to be stronger than the upper arm since the camera has more horizontal displacement. Depending on the situation, that might make the nose arm light enough to compensate for its further displacement from the CG (when considering the overall torque on the glider).

Does that all make sense?

By the way, if you "google" the phrase "weight and balance" you'll come up with lots of information on the calculations that airplane pilots make with regard to positioning various masses at various locations in an aircraft (passengers, luggage, fuel, etc). You'll notice that all of the calculations are based on the distance of the mass from some fixed location. They use a fixed location that's relatively easy to identify and measure from ... even though it's not the CG. The calculations and the bounds on those results are designed to ensure that the overall weight and overall CG are within design specifications.

[TadEareckson]

Zack,

Even if he had done those from the downtubes?

We should be teaching people to fly the way we do.

When a Cessna student parks himself in the cockpit he sits down and straps himself in EXACTLY the way his instructor does and uses controls with the same responsiveness and range as the dual set on the other side. His takeoff will probably look identical to his instructor's and his landing should come pretty close and he'll immediately be working on mirroring it.

I used to head down to the Spectacular competition at Kitty Hawk Kites each May where we earned points by rounding traffic cones. I don't recall ever seeing anyone - Hang One through Five - doing pylons upright with his hands on the downtubes.

This is exactly what they do out at Lookout (well, turning toward cones instead of around).

I want the guys I sign off on Twos to be doing low turns nearly as well as I can.

I'd still like an answer to...

1. It SHOULDN'T.

2. But there's an "if" in that sentence.

3. What's the point in training anyone to fly from the downtubes?

You've been critical of schools waiting before having their students fly prone.

See above.

...(we're speculating).

Which, after studying all the evidence available, is all and the best we can ever do.

Do you think telling that to John would have helped him at all?

Couldn't have made the outcome any worse. Come to think of it... If we had told him to clip in and launch tail first the outcome would almost certainly have been a lot better.

The purpose of telling someone to 'lead with your feet'...

I didn't need to be told too much by my instructors - the glider itself was doing a really great job.

I think the best way to teach control inputs is what Bob said...

I think the best way to learn control inputs is to have your face shoved six inches into the sand when you do things wrong. Worked for me anyway.

I think seeing that is more effective than anything you could tell the student.

Can't hurt.

I wasn't sure about that and Ryan isn't the most trustworthy source with regards to physics...

Stay with that.

If the camera was in the same position but mounted to a beam attached to the keel at the hang point...

1. Assume the mounting hardware and beam is weightless.

2. It makes ABSOLUTELY NO DIFFERENCE what the camera's mounted to. ALL that matters is where the camera ends up.

3. Because THAT'S what / all that affects the glider's center of gravity.

(Exactly as Bob illustrated while I was working on this post.)

Assuming that Ryan's mounting is angled or curved such that the camera is CENTERED in front of the control frame, it has ZERO effect on roll but a bit on pitch - which is massively less of a problem. The glider's center of gravity has been moved a little forward and it will fly a little faster.

If that's the case, the actual shifting of weight that occurs in a roll can't be the cause of the roll because the pilot is still attached to the same point on the glider.

No.

1. Your weight is always (hopefully) pulling down on the glider and air is pushing up on it to resist and reduce your descent rate to something easily survivable or, if it's pushing up harder than normal, allow you to go up and play.

2. The glider is being pulled down on by three different elements at three different points: the hang strap on the keel and the port and starboard sidewires at the corresponding leading edge cross spar junctions.

3. Ignore the nose and tail wires - they don't do much other than allow you to pull in and push out without collapsing the control frame and you could probably bring the glider down in one healthy piece from two thousand feet in smooth air over the salt flats with one pair (preferably the aft) disconnected.

4. A hang glider IS a weight shift controlled aircraft IF the pilot is shifting his own weight rather than having it shifted for him by an electromagnet or towline.

5. When he pulls himself to the left / pushes the control frame to the right he's altering the center of gravity of the pilot/glider system and more heavily loading the left wing so it's feeling more pounds per square foot and the port sidewire is under more tension resisting that force.

6. And the wing warps and the glider rolls to the left.

7. But If he's just being pulled to the left by an electromagnet or towline connected to his Hewett Bridle rather than using muscle the glider will say, "That's odd, gravity seems to have moved to the left and picked up a bit. Better roll accordingly to keep myself perpendicular to it." And the loading on the wings and wires will remained balanced.

So much for Pagen's...

No. He's OK on that. But definitely not OK on THIS:

1982/06

Dear Donnell,

It was with great interest that I read your letter and publication on "Skyting". Your analysis of the forces involved in the towing situation satisfied my technical curiosity and let me know you have done your homework.

...amongst many other things.

...what causes the left wire in your example to tighten?

See above.

What causes the slop transference?

Asymmetrical wing loading.

If the roll is caused entirely by wing warping, how does differential wire tension effect pitch changes (which, to my knowledge, are not caused by wing warping)?

1. Make your passenger plane a flying wing and, while the pilot's flying straight and level at thirty thousand feet, lock up all the control surfaces.

2. Everybody unbuckles and crowds toward the:

-a) left wingtip
-b) right wingtip
-c) cockpit
-a) center aft

3. What would you predict the plane would do in each of the four scenarios?

Wow. I can't believe he said that.

You have any idea how many people that's helped get killed? It's not really important to be able to release with both hands on the basetube 'cause this is an auto correcting system. So you can't lock out unless you've let things get so out of kilter that you or the bridle is in contact with the control frame or a nose wire. (And besides, you've got a weak link which will infallibly and automatically release the glider from tow whenever the tow line tension exceeds the limit for safe operation.)

Regardless, we all know gliders tow better from the pilot than just the glider. Why is that?

We have ALWAYS known that. It just took us a long time to apply it.

The hang glider's hang strap is its tow hook. When we execute a launch run the glider lifts and we're pulling/TOWING it through the air by the hang strap. If you want to allow the pilot to take off from flat ground then tie a rope to him to help him pull harder while he's on the ground and continue pulling after he leaves it.

The control frame is a CONTROL frame - not a tow hook. If you tie a rope to the steering wheel or handlebars you're asking for trouble.

Here's the best explanation I've found...

I still don't know how that works and couldn't find any good pictures after a minimal effort search - however...

1. Build a conventional topless hang glider with sufficient internal structure such that the wings won't fold up when you lose your sidewires.

2. Engineer a magic super strong connection between the control frame apex and the keel such that it can't break, bend, or flex.

3. Now you can throw all your wires away and the glider will fly and handle EXACTLY as before. When you push the bar to the right the left wing will be torqued down by force transmitted through the tubes and spars rather than directly by a pull on the wire.

Interestingly, spoilers create drag, so rigids that use them to roll supposedly don't suffer from adverse yaw.

The Frise aileron does something similar.

Got any more bombs you haven't dropped yet?

The asymmetrical sail color patterns that were all the rage in - I think - the early Nineties were stupid.

Bob,

I believe that if a student is flying in student conditions (as they should be!!), then staying upright may actually be safer since the cross controlling issue is greatly reduced and there's no transitioning to and from prone.

1. If staying upright greatly reduces the cross (not) controlling issue then the student is wasting valuable airtime and not learning how to deal with the cross (not) controlling issue.

2. This perception of yours validates the assessments of Shane Nestle and Danny Jones concerning the most likely major factor involved in John Seward slamming back into the slope at Packsaddle on 2010/06/26 and confirms and reinforces my contempt for this instructional strategy.

3. I never had a problem with a student transitioning TO prone.

4. If a student is flying in student conditions (as he should be!!), then why does he NEED to be transitioning from prone? I can name you a lot of pretty experienced pilots who've gotten majorly int*rcoursed up while or after and because of transitioning from prone - including Zack.

The ability to rapidly, instinctively, and effectively shift one's weight is very important to staying alive.

The dunes at Jockeys Ridge were a great place to learn up to Hang Two level. But to get good you needed airtime and to get airtime at the dunes you needed to be good - Catch-22 sorta thing.

Soaring the dunes - especially the South Bowl in turbulent afternoon conditions (which were pretty much the only conditions in which the South Bowl was soarable) was dangerous and scary.

I remember flying and thinking "The left wing has just gone up and I need to push myself under it to get it back down." And I remember the moment after the left wing had gone up and I suddenly realized I had made the correction automatically without having thought about it or having had the time to have thought about it. (That's what goes on with lift and tuggers at launch, by the way.)

More importantly, a statement like that can plant dangerous misconceptions in his student's minds.

1. Ya think so? Try this one:

Ryan Voight - 2009/11/03

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.

And even that pales in comparison to:

Sam Kellner - 2011/11/07

Preflight, Hangcheck, Know you're hooked in.

2. But since he's got a USHGA instructor ticket he's good for transfer into US Hawks 'cause who are we to judge the meeting of standards.

I think weight shifting is responsible for the glider's response. I believe that shifting weight applies a torque to the glider through the pilot's hands which is rolling the glider. The interplay between the torque and the wing warping is a little more confusing, but I believe that the torque is the prime mover in this situation.

Yes, yes, yes, and yes.

Different people are tuned to different explanations at different times. I remember when I was getting ready to solo a Cessna 150...

This was not a perspective, communication, instructor/student interaction issue. This was a nuts and bolts, physics, standard operating procedures issue. Instructor A dropped the ball / screwed the pouch / didn't RTFM.

Zack,

He wasn't completely sure himself...

Glad he communicated that - but too bad that that's the best we can do with our Uber Instructors.

...and it was just information he got from another source...

Pilots educating pilots. Great.

...I'm just saying (correctly or not) the displacement of weight by itself won't cause a roll.

Not. If you bolt the camera directly to the left side of the basetube the glider's center of gravity will offset to the left, the left sidewire will be under more tension, the left wing will be more heavily loaded, and the billow will shift to the left (but probably not enough so that a flapping batten string at the right tip won't offset the effect).

Let's say the hang strap was perfectly rigid and holding a pilot at the same position he'd be shifting his weight to initiate a roll (with his hands off the basetube).

That would do it. It would be the same as tying yourself to the downtube on that side which would be the same as pulling yourself to that side using the basetube (or, if you must, the downtube).

I can see this would put some torque on the keel...

Don't think torque on the keel. Think center of gravity of the pilot/glider system.

Late thought.

01. You've preflighted your glider and done your hang check therefor you know you're hooked in.

02. After launch you climb back up into the control frame - as a few very strong and lucky hang checkers have been able to do - then place your feet outboard near the basetube ends, grab the downtubes up near the apex, and allow yourself to relax and hang back. (Kunio Yoshimura, sadly, failed on the last of those items and stayed forward inside the control frame and thus made it impossible to get the glider slowed to a manageable speed.)

03. The glider flies great in this configuration and makes the landing flare a piece of cake.

04. Now we can throw out the harness and hang strap and make weight shift roll control maybe a little easier to understand.

05. No, wait. Let's see what else we can get rid of to simplify things.

06. Beef up the internal structure so you don't need the downtubes to act as compression struts to brace the wings to keep them from folding up.

07. Throw out the entire control frame - both downtubes and the basetube.

08. Lose the sidewires and run a single wire - the combined length of the sidewires and basetube - and connect the ends back onto the leading edge cross spar junctions. Have a couple of pairs of stop sleeves swaged on in the foot positions so your feet don't slip sideways along the cable.

09. Run spectra cord from nose to tail, tying it to the cable en route, to replace the nose and tail wires so you can exercise pitch control. Use more stop sleeves to keep the cords properly positioned.

10. Go to Torrey when it's blowing straight in at 25.

11. Get a couple of guys on your wire near its ends. They'll float the wing up and hold it while you grab the hang strap and step on the cable. Then they'll float you to the edge of the cliff and throw you off.

12. You'll turn right immediately (like at Quintana) by pushing to the left on the cable with your feet so you can swing your hips to the right. The strap will be pulled to the right, there will be more tension going to the right end of the cable and proportionally less to the left end, the center of mass will shift right, the right wing will be more heavily loaded and the left will be proportionally less heavily loaded, the billow will shift...

Any of that work, help?

[miguel]

Tad says

3. What's the point in training anyone to fly from the downtubes?

If you start your lessons on a training hill, you start out on the downtubes and remain there until you start out high enough to get into the harness and out of it safely.

If you are erect, you have more roll control than you do when prone. You have less pitch control, but with the so called speed bar, pitch control is adequate. You can also move your legs beyond the plane of your body to accentuate the weight shift forces. If it is turbulent, I sometimes do the whole approach upright.

[TadEareckson]

If you start your lessons on a training hill, you start out on the downtubes and remain there until you start out high enough to get into the harness and out of it safely.

If you start your lessons on a training hill, are you using the kind of harness that you need to get into and out of?

If you are erect, you have more roll control than you do when prone.

1. If you start your lessons on a training hill, how much roll control do you need?

2. Have you ever been in a gaggle and seen anybody go erect because he needed more roll control?

You have less pitch control...

Meaning you have less upper speed range. And the guys who really wanna max out their roll control - the aerobatics competitors - typically stay prone, stuff the bar for a few minutes, and then see how close they can come to blowing a cross spar.

...but with the so called speed bar, pitch control is adequate.

Guys like Tom Perfetti and Gerry Smith have demonstrated that "adequate" sometimes ISN'T. I really like to avoid flying in "adequate" mode - especially close to the ground.

You can also move your legs beyond the plane of your body to accentuate the weight shift forces.

When I pull in prone on approach I've got enough roll control to keep me happy all the way into ground effect and usually have enough left over to keep a starving Ethiopian village going for an extra month.

If it is turbulent, I sometimes do the whole approach upright.

1. I ALWAYS do the precise opposite.

2. If you start your lessons on a training hill, should you be doing your whole approach in turbulence?

3. By the time you're getting to the point at which you're qualified to do your whole approach in turbulence do you need somebody to teach you how to fly upright?

4. Name somebody who was prone ten feet or more above the field who got majorly int*rcoursed up who wouldn't have been had he been upright.

5. Name somebody who got majorly int*rcoursed up because he was taught to fly prone but not upright.

P.S. What kind of harness requires that you be upright on the downtubes for entry and exit?

[miguel]

If you start your lessons on a training hill, you start out on the downtubes and remain there until you start out high enough to get into the harness and out of it safely.

If you start your lessons on a training hill, are you using the kind of harness that you need to get into and out of?

Same concept. You are taught to fly upright so you can be ready to land. When you are learning on a low height training hill, why complicate things by going prone and then upright to land.

If you are erect, you have more roll control than you do when prone.

1. If you start your lessons on a training hill, how much roll control do you need?

How about enough to control the glider in all conditions?

2. Have you ever been in a gaggle and seen anybody go erect because he needed more roll control?

How many training hills have gaggles?

You have less pitch control...

Meaning you have less upper speed range. And the guys who really wanna max out their roll control - the aerobatics competitors - typically stay prone, stuff the bar for a few minutes, and then see how close they can come to blowing a cross spar.

meaning exactly what I wrote. less pitch control. You can and will extrapolate that to whatever you want it to..

...but with the so called speed bar, pitch control is adequate.

Guys like Tom Perfetti and Gerry Smith have demonstrated that "adequate" sometimes ISN'T. I really like to avoid flying in "adequate" mode - especially close to the ground.

You can also move your legs beyond the plane of your body to accentuate the weight shift forces.

When I pull in prone on approach I've got enough roll control to keep me happy all the way into ground effect and usually have enough left over to keep a starving Ethiopian village going for an extra month.

When you come to McClure, I will personally give you a ride up the hill and you can demonstrate a prone approach in turbulence.In the mean time, check out your friend Noman, landing at McClure.

If it is turbulent, I sometimes do the whole approach upright.

1. I ALWAYS do the precise opposite.

Good for you

2. If you start your lessons on a training hill, should you be doing your whole approach in turbulence?

Not following the logic here. Training hills are launch, then land .

3. By the time you're getting to the point at which you're qualified to do your whole approach in turbulence do you need somebody to teach you how to fly upright?

Around here, all pilots know how to fly upright. It is part of learning to fly. I have yet to see a pilot that could not fly upright.

4. Name somebody who was prone ten feet or more above the field who got majorly int*rcoursed up who wouldn't have been had he been upright.

There have been numerous pilots at McClure who have lost control on final while prone and hit trees; some with hospital time. No names. I do not believe in "I am such a great pilot that I would never to what that idiot, pilot y did."

5. Name somebody who got majorly int*rcoursed up because he was taught to fly prone but not upright.

You got me there. I know of no one that was taught to fly prone but not upright.

[Bob Kuczewski]

Bob,

I believe that if a student is flying in student conditions (as they should be!!), then staying upright may actually be safer since the cross controlling issue is greatly reduced and there's no transitioning to and from prone.

1. If staying upright greatly reduces the cross (not) controlling issue then the student is wasting valuable airtime and not learning how to deal with the cross (not) controlling issue.

A quick check of the calendar tells me it's not April Fools Day. So is this really a serious remark?

Ummm ... maybe we'd like students to stay upright longer ... so they can survive their valuable air time long enough to actually benefit from it. Sheesh!  

Tad, I'm not responding to the rest of your post because it starts from the silly assumption that we shouldn't have students learning to fly upright. Joe Greblo sends his students off in mild enough conditions where they can fly their whole 10 minute flight in the upright position. In fact, Joe suggests that advanced pilots should spend some time upright once in a while just to keep familiar with it. I've done that many times at Torrey Pines where I do imaginary landing approaches several hundred feet above the terrain. Flying upright is not something to be feared. It's something to be mastered. Also, as has been pointed out, the upright position gives very good roll control because there's very little chance of cross-controlling. If you want to turn, you bring your hand to your hip ... and you will turn!! You don't have to torque your body or "lead with your feet" or anything else. Just pull yourself in the direction you want to go and your weight will be right there when you need it.

Let me quote you again:

1. If staying upright greatly reduces the cross (not) controlling issue then the student is wasting valuable airtime and not learning how to deal with the cross (not) controlling issue.

I think staying upright long enough to safely clear the terrain is a pretty simple and basic idea. It might sacrifice 10 to 30 seconds of that "valuable airtime", but I think the survival rate is worth that sacrifice. Once the pilot is clear of the terrain (and can fly an unintentional 360 without hitting anything!!) that might be a good time to prone out and experiment with cross-controlling.

Zack, I've said many times that Tad has some good ideas ... and he does. But be careful about listening to everything he says because some of it is just plain wrong. In fact, that goes for all of us - from myself to Ryan Voight (AirThug) and everyone else. Always check us and cross-check us to be sure you're getting the best information and that it stands up to vigorous debate. I think Tad will agree with that approach - although I'm not sure he'll ever agree that he's ever just plain wrong.