Larry said: but I recall that there is no aerodynamic gain in covering the opening with the RAF48 airfoil.
It is my understanding that regardless of airfoil, that the primary benefit, and reason for the wing gap seals for ailerons is for the benefit to climb rate. The drag induced by the angle of attack allowing a significant amount of air to burble through this area and cause drag, regardless of airfoil is the reason for adding the seal. Almost all planes I have flown, in one way or another, seem to have addressed this issue, either through a seal, or the hinge and leading edge being mated like the elevator male and female surfaces (like a half moon formed into each surface for smooth actuation and little drag). Even Cessna Frise ailerons are mated with drag in cruise and climb a consideration by making the area where the hinge is mate with the least aerodynamic drag. Only when deflected do they cause the designed drag to balance the outboard lift/drag induced (but that is another story)... Colin Rainey brokerpi...@bellsouth.net