High-lift flap for use in helicopter rotor blade, has profile stretching along chord and comprising leading and trailing edges and lower and upper surfaces, where flap turns around rotational axis defined based on wing-spread

摘要

The flap has a profile (6) stretching along a chord and including a leading edge, a trailing edge (8), a lower surface and an upper surface. The flap turns around a rotational axis defined based on a flap wing-spread. The lower and upper surfaces present a non-concave shape beyond 25 percent of the chord. The trailing edge presents an angle (alpha ) between lines of the lower and upper surface to the trailing edge. The longitudinal rotational axis is situated at a distance of about 15 percent to 35 percent of the chord of the flap from the leading edge. An independent claim is also included for a helicopter rotor blade including the high-lift flap.