Abstract: The invention comprises a stepped bottom structure of a boat, in which the steps (5) are mainly straight. The number of the steps is from 2 to 4, preferably 3, and the angle between the mainly straight edge (8) of the step and the keel (1) is from 20.degree. to 60.degree., preferably from 20.degree. to 45.degree.. In addition, the bottom structure includes rising laths (10), in which the side (19) facing the keel (1) is narrower than the side (20) facing the side of the boat.

Abstract: A pleasure boat for operation at high speeds in moderate seas, and having a rectangular passenger area, planes on ski-like planing surfaces on the bottom of laterally spaced, knife edge hulls located on the starboard and port sides of the craft. The boat has a centrally symmetrical wedge commencing at the forward transom of the boat and extending to about the beginning of the planing region toward the stern of the boat and a relatively thin plate extending preferably cantilevered, from the bottom surface of the wedge to a sufficient distance forward of the rear transom to accommodate a propeller. The plate is held in a normal position by shock absorbers and a drive shaft from an inboard engine extends through a vertical wall formed by termination of the wedge to a propeller at the stern of the craft, the shaft lying between the bottom of the boat and the plate.

Abstract: Hydrocraft, capable of maintaining comfortable seaworthy performance at both low and high speeds, in both calm and rough seas, wherein its hull form coordinates high efficiency of at least two zero deadrise planing surfaces with a wave piercing, wedge effect bow segment. The forward portion of the respective concave sides of the bow intersect at the centerline of the hull. The sides of the forward body of the hull rise from the bottom at the chine, vertically then upwardly and outwardly in a concave curvature, the form of which will load the side skin in tension. At a preselected point above the hull bottom, the sharp edged bow is truncated in a conical, forward sloping surface to provide an upward hydrodynamic force to lift the hull over waves which are higher than the gunwale. The parallel after body is located above the after planing surface, and a conical transom closes the stern.

Abstract: A deep vee entry hull is disclosed and includes a central running surface flanked in the after portion thereof, by inboard, intermediate and outboard running surfaces. The central and inboard surfaces terminate at the aft ends thereof in a first transverse step while the intermediate running surfaces terminate in a second transverse step aft of the first.

Abstract: This highly engineered recreational catamaran features a unique pivotable mast with a downward extending section that holds an underwater ballast. A hang glider type sail provides lift as well as thrust. Working in combination with the underwater ballast, the sail functions to deliver a high performance sailboat with high stability and ease of control. The ballast also aids in righting a capsized boat. Advanced three tier hydrolift type pontoons raise the boat partially out of the water under full sail thereby minimizing drag and maximizing speed. A convex deck and optional convex cabin facilitate righting an overturned boat. Other advanced features include retractable daggerboards for turning control, telescoping lower mast for shallow water sailing and beaching, underwater battery powered propulsion for movement in a calm wind and power assisted winches for sail lift and turning control.

Abstract: The specification discloses a modified V-hull for a boat in which an elongate pad forms the lowermost portion of the hull. At positions toward the front of the pad, it has a transverse cross-sectional rounded V-shape across its width, but at the back of the pad, the transverse cross-section is almost flat. The pad has a gradually increasingly acute V-shape in transverse cross-section from the back to the front of the pad, and the pad is linear along linear tracks extending from about the longitudinal center (the keel line) of the elongate pad rearwardly at a track angle with respect to the longitudinal center of the pad. The track angle remains approximately constant from about the back to the front of the pad. Also, the pad is linear at its rear end along an infinity of tracks extending from a point on the pad's longitudinal centerline about three feet from the back of the pad to any point on the back of the pad.

Abstract: A hull or flotation arrangement for an apparatus moving through water is provided with steps forming a plurality of surfaces on which the apparatus rides. The steps are arranged such that the lower edges of a predetermined number of the steps extend deeper into the water than a predetermined number of the lower edges of the remaining steps. The lower points of the steps are arranged so that predetermined numbers of them are deeper than predetermined numbers of others, so that there is a progression extending deeper and deeper into the water. The steps are so constructed that as the apparatus is moved forward, it rises upwardly in the water, causing the steps to rise out of the water progressively as the speed increases, with the hull then riding on only a few steps, thus reducing drag and increasing efficiency.

Abstract: A bottom exhaust type high speed boat has a hull including a grooved bottom. The engine exhaust pipe extends into a midportion of the grooved bottom. A duct fixed to the surface of the hull extends between the opening of the exhaust pipe and the front of the grooved bottom for transporting exhaust gases to the front of the grooved bottom. The grooved bottom is separated into a forward part and a rearward part, having different depths, by a stepped surface. The exhaust opening is on the rearward part whereas the duct is on the forward part. Gas leakage prevention grooves surround the grooved bottom. A triangular projection having dovetail sides extends from the grooved bottom and the engine propeller is positioned on the projection.

Abstract: Porpoising control in a high speed planing hull is effected during straight, on plane running and in turning maneuvers by a novel configuration of aft tapered wedges bridging the aft, exit ends of the outboard and next adjacent, inboard running surfaces.

Abstract: High speed turning characteristics of a vee type planing hull are increased by the use of after, outboard running surfaces which are concavely configured and include transverse wedges across the after, inboard halves thereof.

Abstract: A boat hull is provided with a series of steps which are angled toward the center of the hull from the front to the rear of the hull. In order to permit easy riding up of the hull on the steps progressively, as the speed of the hull is increased, the steps are carried over the side of the hull above the normal water line of the hull when the boat is stationary. As the power is increased, the wetted area of the hull is progressively decreased and the friction of the hull and its resistance to forward motion is progressively decreased as the hull rides further out of the water. The principles as described above are applicable to airplane hulls, the wheels of amphibious vehicles, and other variations of normal type boat hulls.

Abstract: The performance characteristics of a vee type planing hull are significantly increased by a combination of features for reducing drag and increasing attitude control.Exemplary of the former are a concave running pad to which air is inducted to reduce hull drag and an angled transom terminating at a transverse hull "step" which permits the outboard propulsion unit to be carried higher reducing unit drag. The presence of longitudinal "wedges" increase hull lift as planing speed is approached allowing the hull to plane at a lower speed.Transverse wedge elements positioned outboard of the concave running pad maintain a stern lifting torque for controlling bow up angle.

Abstract: A hydroplane boat having a hull with two V-shaped sections separated by a step in the hull surface and continuous chines from stem to stern. The void created by the step is preferably provided with air by vents located between the chines, the vents having intakes internal to the boat structure. The hull includes concave portions just aft of the step separated by a pronounced keelson and tapering into a V-shape at the transom, such that the hull portion aft of the step describes a generally hook shaped surface.

Abstract: A sailing-multihull hull shape is disclosed which is designed to produce hydrodynamic lift in addition to static buoyant displacement lift. The dynamic lift is generated in direct proportion to the horizontal surface area times the square of the velocity of this surface through the water. High-lift, relatively low drag horizontal surface area is provided by a series of horizontal steps on V-shaped amas (sponsons or pontoons) and preferably on the center hull, if any. The width of the steps preferably increases from the keel up, so that the widest is nearest the deck. To reduce drag through wake induced turbulence, it is also preferred to rotate back into the basic V-hull shape so that at the stern there are no visible steps. The enhanced lift produced by the steps can significantly increase the stability and righting moment of the sailing-multihull, and allow a greater load carrying ability with less reduction of speed.

Abstract: A planing boat hull having a conical contour extending from the bow portion to the stern for a distance equal to substantially one-third the length of the hull at the keel and two-thirds or more at the chine, the after section of the hull consisting of a flat surface on each side of the keel maintaining a constant dead rise angle of 12 to 18 degrees extending to the wide lipped chine, and a chine lip portion extending at the same angle as the dead rise but in a reverse direction.

Abstract: A power boat hull having sides and a bottom formed of a series of vertically stepped panels disposed symmetrically on either side of the hull center line. The series of panels on either side of the hull center line include an inboard panel, a center panel and an outboard panel. Vertical risers join the adjacent edges of the center and outboard panels and extend substantially parallel to the hull center line. Vertical risers join the adjacent edges of the center and inboard panels and extend on opposite sides of the hull center line from the stern to a point of intersection on the center line adjacent the bow. The panels are angled upwardly from the horizontal, outwardly of the hull center line with such angularities decreasing between successive panels in the outboard direction at all stations along the length of the hull except at the stern, the angularities of each inboard and center panels increasing from the stern toward the bow while the angularities of the outboard panels remain constant.

Abstract: An engine powered water craft comprising a hull including a pair of spaced apart hull elements extending rearwardly therefrom configured to support the craft on the water in combination with a twin rudder system for directional control. The hull further comprises an upper and lower foil extending between the hull elements. The twin rudder system comprises a pair of rudders each including a substantially vertical rudder element having a super cavitating foil element attached to the outer side thereof. The super cavitating foil element comprises a knife-like member extending upwardly at an angle from the vertical rudder element. To counteract engine torque, the rudders are vertically offset relative to each other.

Abstract: A novel bottom configuration for a V-type planing hull which consists of a V-shaped section which extends from the bow to a shoulder located aft of amidships, and a section aft of the shoulder consisting of a partial continuation of the V-sidewalls, joined by a generally horizontal bottom wall which extends to the transom.