Patent ID: 7752986

Claim:
A boat having a shallow draft hull, the hull comprising: a significantly flat bottom extending along a substantial length of the hull, the flat bottom being devoid of a keel structure; port and starboard sides extending between bows and stern of the hull, the port and starboard sides that extend beyond the bows being substantially vertical and slightly inwardly inclined toward the center longitudinal plane of the hull to provide a tumblehome configuration to the hull; wherein the hull progressively increases in width from the bows toward the stern and has a maximum width within the rear 15% waterline length of the hull, and wherein the port and starboard sides diverge from the longitudinal axis of the hull toward the stern; means for controllably introducing air for generating an air cushion under the bottom of the hull for selectively reducing drag on the hull; fore and aft steering rotors comprising elongate fins, the steering rotors disposed on the bottom of the hull substantially along a center longitudinal axis of the hull, the steering rotors being rotatable about a substantially vertical axis and operational for maintaining the hull accurately along its true heading; longitudinal strips disposed on the flat bottom on the port and starboard sides, the strips extending parallel to the center longitudinal axis of the hull and configured to restrain lateral migration of the air cushion; at least one retractable trim surface at the stern for adjusting the attitude and the speed of the hull, the trim surface being retractable into respective recess in the flat bottom for flush alignment with the hull; and propulsion means comprising at least one of a sail and an engine-powered propeller.