Planning to scratch-build a Monterey (100" span, dihedral, full-span straight taper, aspect ratio = approx 16) with several wing sets differing only by airfoil, for different flying conditions.

I want to incorporate flaps - My questions:

1) If flaps are only partial-span (say 50% span), will there be increased tendency for tip-stalling with flaps deployed?

2) To benefit from full-span camber control, if I use full-span flaps of constant width, I sense (maybe incorrectly) that, at a given flap angle, the outboard (narrow-chord) portion of span will be excessively flapped relative to the inboard portion, with reduced L/D along outboard portion of wing?

3) If my presumption in 2) is true, will a flap of constant percentage of chord, i.e. tapered flap, solve the problem?

4) Would it be best to use dual flaps, inboard and outboard, where the outboard flaps deflect less than inboard, regardless of whether the flaps are straight or tapered?

Appreciate any comments.

Regarding #1, I would think you'd reduce the chance of tip stalling, since you've raised the angle of attack of the inner wing, and left the outer wing the same. I would think it would be effectively like adding washout. Ollie?

Right you are, Bjaffe. Flaps always require down elevator compensation to maintain pitch trim when flaps are deployed. That is because the incidence increase overwhelms the pitching moment increase (due to increased camber). By tapering the flaps the designer can control the distribution of twist (washout) due to flap deployment.