Patent ID: 8348198

Claim:
An aircraft comprising: a sail wing having a sail wing root chord length, and wherein the sail wing includes: a sail wing leading edge, substantially rigid spar, a flexible sail wing membrane attached to the sail wing leading edge spar, and a sail wing trailing edge, substantially non-rigid wire connected to and along a trailing edge of the sail wing membrane, the trailing edge wire being unconnected to any rigid structure of the sail wing beyond a trailing edge root, the sail wing having twist and camber which causes nose-down pitching; and a wing surface extension, located aft and at an inboard area of the sail wing trailing edge wire, the wing surface extension having a wing surface extension root chord length, and wherein the wing surface extension includes a wing surface extension membrane attached to the sail wing trailing edge wire, and a wing surface extension trailing edge, and wherein the wing surface extension trailing edge is reflexed such that the wing surface extension trailing edge is positioned upwards at a first angle with respect to a plane formed along a centerline of the aircraft and along the lower surfaces of the sail wing, the wing surface extension trailing edge upward position reducing the downward pitch caused by the sail wing twist and camber.