What profile?

[tigrr]

http://www.edcoatescollection.com/ac1/austu/vhukz.html

I am currently building this above thing.
Ws approximately 1meter, electric power and weight somewhere around 600grams.
From what I see there is no dihedral at all, barn door ailerons and an undercambered sort of wing profile.
I have no special expectations on its behavior in air although it would be nice to have something more wind resistent than the average park flyer.

My question is: What profile should I use?
I am not in a big need to keep the undercambered style.
What I do not want to give up are the ailerons and the straight wing.

[wjbite]

I think that my expectation, if I were building it, would be that I might discover why it wasn't relicenced. Interesting looking plane. Reminds me of the Aeronca C2 - you stuck your foot out of the door (or opening - no door) to drag it on the wheel and stop - 26 horsepower. But then, The C2 had a little bit of dihedral

[BMatthews]

Good ol' ClarkY would work great and offer you a decent but not startling ability in moderate winds. Looking closely at the picture there does not seem to be much, if any, undercamber in it so the Clark Y would be a good fit. By ClarkY I mean the proper one and not something drawn around a shoe sole.

Keep the wing flat and use ailerons. Be sure to use a fair amount of differential so the up travel is easily twice the down travel. This will greatly help avoid low and slow tip stalling.

Interesting design. All the best of luck with it.

[tigrr]

Thanks for the tip.
I'll have a go with Clark Y.
I got the coords out from Profili.
There is one (two actually) thing that I would like to know.
Where is zero incidence on the profile?
What do you think would be proper incidence?
I never bothered much about this out before but then I always
had some kind of worked out and flight tested plan.
This time I'm on my own pret
ty much.

[BMatthews]

Zero incidence is always from the leading edge to the trailing edge. The flat bottom of the ClarkY is often used instead by folks that don't remember this convention.

Using the flat bottom on the same line or parallel to the stabilizer gives you about 2 degrees of the proper incidence angle between the two.

[Ollie]

The function of incidence is rigging the plane at the shop. The function of decalage, between wing and tail, is trimming in a first test flight of your design. (That's where the elevator tab are on the transmiter.) In a new design, it is an important function to adjust the decalage.

That's only my point of view.

In a new design, the problem is decalage and thrust angle offset in pitch and yaw. In the simpler glider, read about:
http://www.fatlion.com/sailplanes/decalage.html