Does anyone have a source for aero data on the tradeoffs between a top-hinged and bottom-hinged simple flap? A NACA TR would be most excellent, and I'm sure there is one, I just can't stir it up. Obviously the bottom-hinged flap will be "better" in many ways (larger chord with downward deflection, smoother flow, etc), but I'd love to see some wind tunnel numbers, especially for the sharp-hinge-in-flow issue (the difference in chord is easy to deal with).