Yes, moving the CP inboard is done a number of ways but first and foremost, by a high taper. Too high of a taper and you get unwanted consequences. Not enough and you lose the effect. I think the Tempest is about as far as you can go without getting too many wierd side effects. It's a 20" root and 7.5" tip. I also used a completely built up structure and used small light aileron servos (9411SAs) and hollowed the tips. The panels are about 13 ozs flying each. Most of that is inboard. All this does is dampens the snap exit. I have noticed the wings getting kicked around a good bit in very turbulent crosswinds, so I know I'm close to the edge of the limit for our purposes. On my new one I went back the other way a bit, 18.5" at the root and 9" at the tip. I used 11% at the root and 12% at the tip. It's pretty much a straight NACA 0011 and 0012 with the high points at about 31%. That's pretty far forward for a modern design. For comparison the Patriot has the thick point around 50%. It's the wierdest pattern airfoil I have seen, and it works.

And yes sweep the tips forward, the aerodynamic center is moved forward as well.

Why don't all planes have the wing/stab mounted on the thrust line? Well, design parameters a-plenty. I'm not the one to ask this question. The only plane I know of that is true 0-0-0 is the Patriot, and it's pretty true in the rolling manuevers. But there are so many more aerodynamic and other considerations, I couldn't possibly list them.

Pattern planes don't have a standard airfoil, they vary from plane to plane. Everybody thinks they have a better idea that works better. Some do, some don't. The Prophecy wing became the standard for a long time, very thin and double tapered (planform). Then the euro stuff became popular, and again things shifted a little. The truth is, airfoil doesn't really matter a lot. The planform is a lot more important, getting the sweeps and areas correct. You do that and you can use just about any airfoil effectively, within reason. Of course if you get too thick, it flies more like a fun fly than a pattern plane.

Arrrgh my brain is frying. Dick is right about thick airfoils, it really doesn't add much drag. Some, but only a small amount of profile drag, and not enough to use it to slow a plane. If you increase the wing area, induced drag increases and there's a better ticket....but then you get into that wierd snapping wind up thing if you go too far. Any wing will snap, it's just a matter of what it takes to make it do so, and even moreso...predictably. The harder you have to push to stall a wing, the deeper the stall, and the harder it will be to come out straight. That's sort of ok for IMAC, but not ok for us. Pattern guys can't even agree on how to score one properly!

A better way to slow down a plane (as Dick said...again...) is prop disc. If you have a large diameter prop turning the same rpm, your down line will be slower if you can keep the engine from winding up. (a large advantage for electrics, then 4 strokes, and 2 strokes require the most work to get that effect).

I wouldn't add that to any book of "truth". I'd add it in the "tested and somewhat proven theory" dept. Notice there is still a NASA test center for flight? Cuz we don't have all the answers. We're only beginning to understand the questions.

This is just some of the theory I'm playing with. In my experience, it's been pretty repeatable so far. But we're always pushing the envelope. Always trying new stuff. Look at the planes now: they'll be totally different in 2010, if it even takes that long. A Prophecy and Typhoon 2000 were the stuff 5 years ago, and look how old they look today. It's never ending, and that's good for us that like to play. I can't say I agree with the construction techniques and the thinking that we all have to fly composite planes made in europe, but I do like the way the designs have gone. I just don't think they should cost NEARLY as much as they do.

But that's just my opinion, I could be wrong......

And still nobody wants to address the anhedral stab thingy.......why was it so popular, why is it gone, and why is Naruke doing it again (and even Nat Penton?)

-Mike