Dumb question, but help please!

[DeaninMilwaukee]

I've owned a bunch of planes now, but I've never had one with a flat bottom airfoil before so I have'nt run into this.

On a flat bottom airfoil, would flat ailerons ( coroplast) be angled down to match the upper airfoil shape, or should they be flat ( straight back) to line up straight with the flat bottom?

The plane is a split 280, and I tried it angled down to match the airfoil, and the plane seems to suffer excess drag, although I could be imagining things. :rolleyes:


Thanks for the help,

Dean in Milwaukee

[Sparky Paul]

Angling the ailerons down makes the wing undercambered.
Usually "straight-back" is the way it's done.
But it's your choice. You can try it both ways.

[DeaninMilwaukee]

Thanks Paul.

Even though the wing is pretty thin on this model, and therefore the ailerons don't point down a whole lot, it was enough to force me to actually trim in all the down my flash 5 could come up with, and even then, it wanted to climb a bit.

I would have to imagine that flying nose down to maintain level flight must make an awful lot of induced drag, and on a plane running a little zagi prop, this is not a good thing!

Speed was pretty low, much slower than a stock zagi, even though I was running over 10 amps on 6 cells. Pitch speed should be 64 mph, and this plane is pylonesqe looking and only 160 in/sq. It should've been fairly speedy.

I kept thinking of the fun flys that couple flaps to elvator to make REALLY tight loops, and in fact, when I could get some speed up, it did loops pretty tightly with not much elevator.

I will be trying again tommorrow with ailerons straight back.

Dean in Milwaukee