US Patent 7802754 Tilt outboard wing for tilt rotor aircraft

Tilt-rotor aircraft experience increased efficiency and fuel economy by including wing extensions outboard of the tilting nacelles. Stall and buffeting during conversion from rotor-born hover to wing-born forward flight are reduced to an acceptable level using wide chord flaps deflected upwards by at least 15-20°, preferably in combination with leading edge slats. The outboard wing or wing portion preferably has a span at least 25-40% of a span of the inboard section, and a total surface area at least 10-20% the total surface area of the corresponding inboard section.