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FT P-40 Flaperons / Differential Ailerons / Control Surface Throws

#1
I have just finished building the FT P-40 and have some radio set up questions. I see the recommend throws are 12 degrees. Will this be enough for rolls and loops and whatnot?

More importantly, has anyone tried to use flaperons with this model? I want to try it but am curious if it has serious tip stall problems, and need a good angle for full flaperons. I am also wondering if differential ailerons are necessary and to what extent they should be applied.

Any general setup tips are welcome as well, Thanks!
 

JasonK

Participation Award Recipient
#2
if your doing flaperons, you typically want full wing control surfaces, not just 'tip' surfaces. I believe it has to do with tip stalling issues.
 
#3
I have just finished building the FT P-40 and have some radio set up questions. I see the recommend throws are 12 degrees. Will this be enough for rolls and loops and whatnot?

More importantly, has anyone tried to use flaperons with this model? I want to try it but am curious if it has serious tip stall problems, and need a good angle for full flaperons. I am also wondering if differential ailerons are necessary and to what extent they should be applied.

Any general setup tips are welcome as well, Thanks!
I would personally consider 12 degrees to be low rates. I usually aim for 30 ish degrees for normal planes, 45 or more for aerobatically-oriented planes, with around 25% expo. It's very much a personal preference thing, but I'd prefer to have too much control authority rather than not enough - If I'm just doing flying around the pattern, I'll rarely exceed 1/2 of the maximum stick movement either way in any control axis.

As for flaperons, I would not recommend them on the outboard ailerons without inboard flaps. They increase the effective angle of attack of the outboard wing sections (effectively forming "wash-in") and drastically exacerbate tip-stall tendencies. If you'd like to do some form of high-lift, you can always hinge the inboard trailing edge and turn them into standard flaps - I've done this on the FT Otter with success.

The purpose of differential ailerons is to reduce adverse yaw. Dialing in some differential will reduce cross-control roll coupling and make the plane fly a bit better, but will reduce the maximum roll rate slightly.