Flat Horizontal Stab & Elevator or Tapered?
 

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

RE: Flat Horizontal Stab & Elevator or Tapered?
 

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

RE: Flat Horizontal Stab & Elevator or Tapered?
 

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