Abstract: The disclosed watercraft hull has a flat pad keel whose width tapers towards the bow and its width at the transom is 15% to 25% of the hull's width at its chines. The hull is symmetric about its centerline, has a fine entry bow, a transom, and a pair of hard chines. Between the pad keel and the chines the hull has at least one pair of generally flat panels referred to herein as longitudinal steps having approximately 0 degrees of deadrize forming planing surfaces symmetrically located about the hull centerline. The hull also includes at least one pair of ultra high deadrize panels, outboard of and adjacent to the pad keel, located symmetrically about the hull centerline, and extending therefrom to the flat planing panels above them. The ultra high deadrize panels have a minimum average deadrize of approximately 50 degrees measured along their length.

Abstract: A watercraft hull has a flat pad keel whose beam tapers towards the bow and at the transom is 15% to 25% of the beam at its chines. The hull is symmetric about its centerline, has a fine entry bow, and a pair of hard chines. Between the pad keel and the chines the hull has at least one pair of generally flat longitudinal steps having approximately 0 degrees of deadrise forming planing surfaces symmetrically about the hull centerline. The hull also includes at least one pair of ultra high deadrise panels, outboard of and adjacent to the pad keel, symmetrically about the hull centerline, and extending to the flat planing panels above them. The ultra high deadrise panels have a deadrise approximately 50 degrees. Additional flat planing surface structures having approximately 0° deadrise are installed longitudinally on the hull between the pad keel and the hard chine.

Abstract: An engine-powered watercraft includes three parallel hulls, namely a center hull with two or more transverse steps, and two smaller outer hulls or amas on either side of the center hull that are configured to form two vent ducts on either side of the center hull, disposed between the center hull sides and the amas. The amas, steps and vent ducts are disposed along the length of the watercraft and are configured to enable high speed capability and to facilitate pressurization of the vent ducts. The pressurized vent duct maximizes ventilation of the running bottom of the watercraft so as to improve efficiency and to reduce drag thereon. The pressurized vent duct creates an area of lift at the widest, aft-most points of the running bottom, which thereby results in improving the transverse and longitudinal stability of the watercraft and in reducing the trim for better seakeeping.

Abstract: An engine-powered watercraft includes three parallel hulls, namely a center hull with two or more transverse steps, and two smaller outer hulls or amas on either side of the center hull that are configured to form two vent ducts on either side of the center hull, disposed between the center hull sides and the amas. The amas, steps and vent ducts are disposed along the length of the watercraft and are configured to enable high speed capability and to facilitate pressurization of the vent ducts. The pressurized vent duct maximizes ventilation of the running bottom of the watercraft so as to improve efficiency and to reduce drag thereon. The pressurized vent duct creates an area of lift at the widest, aft-most points of the running bottom, which thereby results in improving the transverse and longitudinal stability of the watercraft and in reducing the trim for better seakeeping.

Abstract: A boat hull has an aft swept ventilated area in at least a part of its bottom planing surface. An aft swept water flow interrupter is positioned to project downwardly from the hull forward of the ventilated area. The aft swept flow interrupter has two generally angularly related legs or sections defining a 30° to 70° included angle, increase lift on the hull, reduces wetted surface area and improves the turning characteristics of the hull.

Abstract: A boat hull has at least one generally transverse ventilation step formed in at least a part of its bottom planing surface open to the water. The step has a forward edge portion and a water flow interrupter is positioned to project downwardly from the hull forward of the forward edge of the step.

Abstract: A boat hull has an aft swept ventilated area in at least a part of its bottom planing surface. An aft swept water flow interrupter is positioned to project downwardly from the hull forward of the ventilated area. The aft swept flow interrupter has two generally angularly related legs or sections defining a 30° to 70° included angle, increase lift on the hull, reduces wetted surface area and improves the turning characteristics of the hull.

Abstract: A boat hull has at least one generally transverse ventilation step formed in at least a part of its bottom planing surface open to the water. The step has a forward edge portion and a water flow interrupter is positioned to project downwardly from the hull forward of the forward edge of the step.