Airplane with variable-incidence wing

Abstract

The craft is for hovering flight, vertical takeoff and landing, and horizontal forward flight. It has a tail-sitting fuselage and a ducted fan mounted to the fuselage aft to provide propulsion in both (a) hovering and vertical flight and (b) horizontal forward flight. At each side is a floating wing, supported from the fuselage for passive rotation (or an actuator-controlled optimized emulation of such rotation) about a spanwise axis, to give lift in forward flight. The fuselage attitude varies between vertical in hovering and vertical flight, and generally horizontal in forward flight. Preferably the fuselage is not articulated; there is just one fan, the sole source of propulsion, rotating about only an axis parallel to the fuselage; and thrust-vectoring control vanes operate aft of the fan. Preferably at each side a small, nonrotating wing segment is fixed to the fuselage, and the floating wing defines--along its trailing portions--a corner notch or slot near the fuselage; forward portions of the fixed wing segment are within this notch. Preferably the spanwise axis is along a surface of the floating wing, and a long hinge supports that wing from the fixed wing segment, within the notch. During vertical and transitional flight characteristically the leading edge of the floating wing is down relative to the fuselage axis.