ORIGINAL: Andrew Ditchfield
I made some built up ailerons to replace the heavy balsa stock that came with a kit I am building. Now that I have the plane covered with the ailerons in (hinged but not glued yet), I notice that the leading edge of the airelrons are about 1/16th inch thicker than the trailing edge of the wing that they butt up against.
I remember reading somewhere that it is bad to have the ailerons thicker than the wing, but I dont' know how much thicker it has to be before it becomes a problem. Can anyone give me advice on this? I am trying to decide if I should rebuild new ailerons.
Andrew
Some years back, thicker ailerons were sort of a fad in C/L stunt. Of course, they were acting as flaps on our stunters, but that's not actually relevant. And matter of fact, C/L is about the best test environment you can ever hope for.
The idea that was touted for the deal was that the depression along the hinge line insured the boundary layer had to break up along that line so....... by having an effective dam in the flow, the depression (there still would be one) would fill up with stagnant air and the boundary layer would basically have a more constant surface to follow (even if the surface had a section made up of trapped air) and wouldn't detach. The idea was that the boundary would have a somewhat constant and positive path to follow. Nothing it encountered would be encouraging it to detach. Everything it ran into would encourage it's continued attachment. Or so the story went.
Turns out that the only negative anyone (with the flying skills to know) discovered was that the flaps were somewhat more effective. And it appeared that some designs and some retrofitted models seemed to be a bit faster. And it appeared that was only when there was no control input.
It appeared that the initial control input gave a quicker move into the turn. And it appeared that the amount of deflection you held didn't change at all. And that the neutral position was somewhat cleaner for drag. All that made some sense.
We got sharper turns and really didn't have to re-rig the control systems. Only problem was the airplanes were a bit "hunty" in level flight. Turned out that minor control input got quicker results. And we didn't want level flight to be harder to fly smoothly. And we didn't have exponential to take care of the situation.
I wouldn't worry a bit about your problem. It actually isn't a problem at all, but could be considered a design enhancement. At least if you're flying before judges, you should make sure to loudly explain all the magic positives you are getting from you very clever and superior design.
That's what we did at all the contests.
You got no worries with that deal. For heavens sake, don't build new ones.