Abstract: A sliding boat having supporting members respectively connected to opposite sides of the hull and projecting therefrom in cantilever fashion while carrying a plurality of water sliding foils at the free end of said supporting members. Each of the sliding foils comprises a plurality of relatively long and narrow strips extending in the longitudinal direction of the boat and being spaced from each other in the transverse direction of the strips so as to form a gap there between.

Abstract: A sliding boat having supporting members respectively connected to opposite sides of the hull and projecting therefrom in cantilever fashion while carrying a plurality of water sliding foils at the free end of said supporting members. Each of the sliding foils comprises a plurality of relatively long and narrow strips extending in the longitudinal direction of the boat and being spaced from each other in the transverse direction of the strips so as to form a gap therebetween.

Abstract: A sailboat having a hull, a sail assembly and a keel. The keel is shaped as a longitudinally and horizontally extending hydrofoil which developes a vertically downward force. When the boat is traveling in a heeled position, the keel member exerts a downwardly and outwardly directed keel force having a lateral force component to substantially counteract an opposite lateral aerodynamic force component exerted by wind against the sail assembly, thus diminishing the yaw angle in the travel of the boat. Further, the keel force acts through the center of gravity of the boat to produce a righting moment which tends to counteract the capsizing moment developed by the force of the wind against the sail assembly.

Abstract: The invention concerns a water craft comprising a hull, a front hydrofoil and a rear hydrofoil depending downwardly from the hull, a hydrofoil depending outwardly from each side of the hull at an angle below the horizontal, a sail wing or the like for enabling the hull to move forwards and control members for altering the position of at least some of the hydrofoils.

Abstract: Apparatus for steering a hydrofoil ship by the combination of one or more trailing-edge or spade rudders in combination with means for controlling the side forces on a vertical, fixed strut or horizontal foil which pierces the water. The means for controlling side forces comprises an elongated roller or rollers mounted on the leading edge of the strut or foil. In the case of the vertical strut, the roller is stationary and has no effect when the craft is not turning. However, when turning, the roller is rotated about its own axis in the direction of the turn to produce a pressure decrease which minimizes the resistance to water flow on the side facing the direction of turn. In the case of a horizontal foil, the roller rotates in a direction to decrease pressure on the upper surface and increase it below, thereby creating greater lift.

Abstract: A stabilizer keel for water surface vehicles. The keel includes a pair of pivoted keel plates that are pivoted on a stationary base member by an integral hinge. The plates are urged apart about the axis of the hinge to normally form a V-configuration for the purpose of stabilizing the object to which the keel is mounted; for example, a water ski. The hinge axis is inclined so the plates, when in the open, V-configuration, will lift upwardly against the ski upon movement of the ski in a forward direction. As forward velocity is increased, pressure against the plates also increases, causing them to swing inwardly against resistance of the spring. Thus, at relatively high speeds, the plates come together to form a substantially standard shaped keel.

Abstract: A depressing force in the form of negative lift is hydrodynamically generd on a towed underwater vehicle as a result of fluid in motion passing static fluid separated by a membrane so as to cause a negative pressure zone externally of the membrane. The external negative pressure enhances distension of the membrane into a water foil generating additional negative lift.

Abstract: A predetermined-sized and shaped foil-fence structure which is substantially perpendicularly mounted at the foil-tip of a hydrofoil craft and projects downward, upward or partly downward and upward from the foil-tip. The fence surfaces are generally disposed parallel to the longitudinal axis of the craft.

Abstract: One or more hollow elongated structures are mounted on the underside of a boat to provide wave-forming lift surfaces. Each structure defines a chamber which substantially parallels the length of the boat. Each structure has a pointed, closed forward end, an open rearward end, and an outer surface which tapers, at least in part, to provide a smooth transition between the ends and to define a planing surface that increases in area as it approaches the rearward end. When the boat is at rest, water enters the chamber and helps to stabilize the boat. When the boat gets underway, the chamber empties and the planing action of the outer surface lifts the boat and reduces its wetted surface area. Emptying water from the chamber is facilitated by ducting air or exhaust gases into the chamber. Ducting exhaust gases into the chamber has the advantages of muffling exhaust noise and reducing engine back pressure when the boat is underway, thereby enhancing engine performance.

Abstract: An airplane which is universally adaptable to land on any type of flat surface, such as water, snow, ice, as well as land. The landing pods of the aircraft include a wheel with a V-shaped ski surface surrounding each wheel. Each landing pod is constructed in the shape of a hydrofoil for moving through water and creating lift. A boat is detachably securable to the underside of the fuselage of the aircraft. The boat functions as pontoons when the plane is landing and parked on water.

Abstract: A boat hull comprising a generally elongated body portion and port and starboard elongated sponsons disposed along the opposite side margins of the body portion and defining elongated running surfaces, the sponsons terminating at respective locations forward of the transom means but aft of the transverse midplane of the hull. A central sponson depends from the body portion centrally of the port and starboard sponsons and defines a further elongated running surface that extends from a location forwardly of the aft terminal ends of the port and starboard sponsons to the approximate location of the transom means. The sponsons, in combination with the body of the hull, define tunnels on opposite sides of the central sponson. These tunnels are open at their respective forward and aft ends for the flow of fluid therealong.

Abstract: A boat is provided with an elongated vane extending along each side of the hull. This vane is supported in a closely spaced relationship with the hull's surface to define a longitudinally extending slot. The vanes so positioned reduce the tendency of the boat hull to drift out on turns, by biting into the water. These vanes may be provided with mechanisms to close off the slot when not needed.