I am working on a 40% scale Cassutt racer as an IMAC / sport pattern aircraft. The full scale aircraft has a flat stab and elevator made from a round tube frame work covered with fabric. I am planning on making mine with balsa sheeted over foam or a balsa framework. Should I just use a flat elevator and stab, or taper the elevator surfaces some? The planform shape of the elevator does not lend itself to an airfoiled section or I would do that.

Thanks,
Mark

QQ Somenzini's 100cc Python has a flat stab and elevator . . (I think his 200cc version did too?). See attached pics. Hope they are clear enough.

The elevators also appear to be not taperred much at all leaving a very 'blunt' trailing edge. Current trends with F3A Aeobatic/Pattern planes is to have VERY blunt trailing edges on all surfaces . . I have heard of up to 12mm (1/2") being used. This appears to soften the control around neutral, and I expect it would create extra drag . . a desirable feature in modern day pattern flying.

I think that if you build it as per the original full size, it would fly just fine.

Cheers, Jeff

Jeff,

Thanks for that info. If it's good enough for QQ, then my duffer thumbs will never know the difference. I am thinking that the core will be 3/8" or 1/2" thick with 1/16" skins and it should be fine structurally and will definitely have a thick, blunt TE.

Mark