The problem is that this would be right in front of the prop. OK for a sailplane, but not good for a powered plane.Norman knows the theory, he successfully specified the flap size and location for one of my constant chord swept 'wing rc gliders.
With my higher aspect ratio 'wings I've found it's better if the flapped area goes all the way to the root. If the flap doesn't
extend fully inboard, I found you can experience a stall of the central, unflapped area of the wing. This manifests itself
as a sudden, uncontrollable pitch down of the nose just when you're getting ready to flare for touchdown.
I have the formula for a nontapered wing, but want to know what it is with a taper.
I thought I remember seeing a design that did not go all the way to the root, but can't find it.