Abstract: A planing boat including: a hull having a boarding area; a screw unit having a screw, and configured to be rotatable with respect to the hull so that the expulsion direction of a water current by the screw can vary by 360 degrees; and a direction change mechanism having a turning drive force source, and configured to change the expulsion direction by rotating the screw unit with respect to the hull with a drive force of the turning drive force source.

Abstract: An improved boat hull is described. The new hull includes a bow, a stern and a lower longitudinal keel extending between the bow and stern. The hull includes a first V hull formed at the bow and a second V hull formed aft the bow. The second V hull is defined by a bilaterally symmetrical indention having a forward end and a rearward end. The indention is directed rearwardly and outwardly from the lower longitudinal keel, and the rearward end of the indention is above the water line for displacement of water toward the stern on both the portside and starboard side of the boat. The new hull provides a smooth, less jarring ride, a reduction of drag forces, and an improved load along with increased deck area.

Abstract: The rudder arrangement for ships comprises a twisted balanced rudder blade having a slender profile and having a low profile thickness and comprising a propeller facing the rudder blade and a rudder pipe located in the upper region of the rudder blade with rudder post located therein, wherein the rudder blade comprises two superposed rudder blade sections having different heights whose front nose strips facing the propeller are offset in such a manner that one nose strip is offset to port or starboard and the other nose strip is offset to starboard or port, wherein the two side wall surfaces of the rudder blade converge into an end strip facing away from the propeller and have different arc profiles.

Abstract: An improved boat hull which is useful for various types of boating activities; having a top or perimeter surface, curvilinear bottom surface, curvilinear side surfaces, curvilinear front and rear surfaces. Hull is formed, fabricated or manufactured as a combination of compound curves and straights. The top or perimeter of the hull is to be attached to a standard or non-standard deck configuration. The front, sides and rear of the hull are convex, concave, compound curves and straights, for engaging in contact with water and with a combination of water and air. The front end or bow section of the hull features primarily convex/outward construction in a rounded or somewhat of a ‘v’ shaped configuration, while the remaining portion of the hull graduating to the rear and exiting at the stern, or transom, features a series of concave and convex curves and straights producing a dual-hull or somewhat of a double ‘v’ tunnel configuration.

Abstract: A hull for shipping with a mono-three-catamaran architecture comprises a bow point (11) connected to hull sides (14, 15) that ends at a stern (12); a pair of chines (17, 18) disposed laterally to a center line (X—X), a keel (13) extending along the center line (X—X) on the underside of the hull aftward from the bow point (11) for a length less than the distance between the bow point (11) and the midship section (5); a bottom (16) extending laterally between the chines (17, 18), and between every chine (17, 18) and the keel (13), where the keel (13) is present, forming inverted longitudinal bottom channels (26, 27).

Abstract: A pedal-powered watercraft comprises a unitary hull having an upper wall extending from a bow portion to a stern portion of the watercraft and a pair of spaced hollow sponsons located on either side of the upper wall. The upper wall together with inner walls of the sponsons form a tunnel that opens generally downwardly and extends from the bow portion to the stern portion of the watercraft. A deck is connected to the hull and includes an elongate opening that defines a cockpit area for receiving an occupant. A seat is located in the cockpit area and a pedal assembly is connected to the hull forwardly of the seat. The pedal assembly includes a pivotal pedal tower and a pair of pedals rotatably mounted on the pedal tower. The pair of pedals are operably connected to drive the propeller during pedal rotation.

Abstract: A new Hydro-Lift Boat Hull for offering greater stability and higher speeds. The inventive device includes a keel portion having a keel channel provided therein, a pair of opposed chines positioned on opposite sides of the keel portion, a pair of angled panels symmetrically positioned about the keel portion intermediate the keel channel and the pair of opposed chines, and a pair of opposed gunwales extending upward from the pair of opposed chines, wherein each of the pair angled panels has a chine channel provided therein adjacent each of the pair opposed chines. The lower edge of each of the pair of angled panels extends into the water surface, whereby the pair of angled panels and the keel channel define a water capturing keel tunnel. The base portion of each of the pair of opposed chines extends into the water surface, whereby the pair of opposed chines and the chine channels define a pair of opposed water capturing chine tunnels.

Abstract: The Multiple Concavity Surfing Ship and Transition System is an improvement for a surfing ship that generates a singular water wave and rides on its crest efficiently at high speeds. The improved system now adds provisions to aid in the ship's transition in lifting the ship upwards from its low speed displacement mode deep in the water to its high speed surfing mode on top of the ocean surface and to enhance stability and control during transition and cruise. Two complementary features to assist in this transition are provided, the first comprising one or more pairs of hydrofoils on either side of the ship near its bottom to increase surface area and span to lift the ship upwards at the low speed beginning of its transition, and second, one or more sets of concavities preferably symmetric nested concavities, of increasing camber on the bottom of the ship itself to reduce the wetted area in a controlled manner as the ship approaches its cruise mode at high speeds.

Abstract: A boat hull constructed with an inverted U-shaped hull bottom, hull sides which are vertical below the at-rest water line and outwardly curved in a deep arc above the at-rest water line, and a rudderless, arcuate concave tunnel from bow to stern is disclosed. Preferably, the port and starboard gunwales are parallel and the port and starboard chines are parallel. The inventive boat hull is capable of smoothly and rapidly assuming a hydroplaning position without use of submerged hydrofoils, and without pounding upon waves. The hull is navigable in fouled water, substantially reduces water sprayed aboard, and eliminates "tripping" when navigated through sharp turns.

Abstract: The present invention relates to a hydrodynamically designed concave hull having longitudinally positioned chined rails at the outermost edges of the concave scoops. Each pair of concave scoops have a central longitudinally positioned median V-shaped groove to channel water and facilitate steering of the hull.

Abstract: There is disclosed an inverted bottom structure having generally convex, longitudinal buttock and waterlines lines which creates a venturi structure and a variable pressure/suction situation along the boat hull bottom. The under sides of the boat hull are highly concave resulting in the varying speed of flow which limits the throw-out of water wake while the inverted bottom of the boat hull eliminates turbulent, drag flow. The depth of the longitudinal bottom channels progressively deepens, thereby encompassing a growing volume of smooth water flowing aft in the channels which creates inertia lateral resistance while causing minimal increase in resistance to forward movement. The finely contoured, longitudinal, horizontal and cross sectional lines create a controlled flow situation whereby uncontrolled turbulent flow is replaced with controlled laminar flow, introducing an unprecedented reduction in resistance, to forward movement per displacement, and a profound increase in lateral resistance.

Abstract: A surfing ship that generates a singular water wave and rides on its crest efficiently at high speeds. Two complementary features to assist in the transition from displacement mode to high speed surfing mode comprise a pair of hydrofoils on either side of the ship near its bottom to increase surface area and span to lift the ship upwards at the low speed beginning of its transition, and a set of symmetric nested concavities of increasing camber on the bottom of the ship itself to reduce the wetted area in a controlled manner as the ship approaches its cruise mode at high speeds. The hydrofoils are retractable, enabling their extension for transition and cruise and their retraction for high speed cruise. Intermediate positions of the hydrofoils also offer the possibility of dihedral to aid in roll stability.

Abstract: A steering mechanism for a boat utilizing a hull which is provided with a rudder apparatus. The rudder apparatus has an end portion extending outwardly from the boat hull with top and bottom portions. The rudder apparatus may be turned or flipped transversely relative to the boat hull and/or twisted such that the top portion of the rudder apparatus and the bottom portion of the rudder apparatus are moved transversely and oppositely relative to one another.

Abstract: A boat with dual hulls is constructed of outwardly concave cylindrical hull plates that are substantially free of compound curvature. The respective hull portions may be closed at their ends by outwardly concave cylindrical bow and stern plates.

Abstract: A sailing-boat hull includes a bottom (C) provided with a projecting keel (12) of U-shaped cross-section which is connected laterally to the sides (F) by two longitudinal channels (14) of rounded section so as to define, with the sides (F), two longitudinal side portions (16) of rounded section extending substantially the entire length of the hull. The rounded side portions (16) of the bottom (C) are situated at a higher level than the keel (12).

Abstract: A hull configuration for a watercraft that improves stability in straight ahead running without significantly increasing the resistance to forward movement. The hull is comprised of a generally flat center section that is surrounded on each longitudinal side by a pair of arcuate sections, the outer peripheries of which are defined by respective chines.

Abstract: A tunnel-type boat-hull construction is operative with substantially reduced frictional resistance in the water and also with improved high-speed stability. An air-withdrawal port is provided in the bow portion of the tunnel, and exit ports which are interconnected to the withdrawal port are provided along generally downwardly facing submerged surfaces of the hull. When the boat hull is operated in a forward direction, air is captured in the forward portion of the tunnel, and a portion of the air is withdrawn through the withdrawal port and is exited through the exit ports. The air which is exited through the exit ports provides lubrication for the submerged hull surfaces so that the hull is operative with substantially improved efficiency; and because the air is withdrawn from the bow portion of the tunnel, the bow uplift effects which are characteristic of conventional tunnel-hull-type vessels when they have been operated under high-speed conditions are substantially reduced.

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: A boat hull has a bottom formed with a modified V-shaped longitudinal surface forming the keel and has a tunnel surface disposed on each side of the keel. Both tunnel surfaces have substantially vertical and parallel side surfaces connected by a substantially horizontal surface which is parallel to a base plane in a transverse direction. The outboard side surfaces of each tunnel surface have a transition portion starting aft of the midship section which portion transforms to a respective incline surface at the stern, which surface slopes outwardly and downwardly. The hull also has an outboard flat bottom disposed on each side of the tunnel surfaces. Inboard of each tunnel surface, the modified V-shaped keel has inclined longitudinal surfaces inclining upwards towards the centerline.

Abstract: A boat hull having a bow and stern and requiring relatively small draft, having low frictional drag characteristics for high speed, stable performance, wherein the hull has a scooped configuration and defines a tri-keel design, wherein the side and bottom walls, making up the hull, define a first, open scoop portion and a second primary keel portion. The open scoop protion is of concave, curvilinear configuration and extends to a point rearwardly of the mid-point of the hull where it merges into the second or primary keel portion. The bottom and side walls of primary keel portion are V-shaped in configuration to thereby define the primary keel which extends from the merging surface to the stern. The first and second portions also cooperatively define about co-extensively therewith, extending from the open scoop portion, a pair of spaced apart secondary keels which extend from the approximate box of the hull to the stern thereof.

Abstract: A monolithic ship's body is formed of a hull containing bulkhead partitions disposed in a hexagonal arrangement to form a grid symmetrical about the longitudinal axis of the hull. The partitions are formed integrally with the hull. The junction between the side walls and the bottom of the hull is curved. Further, the bottom of the hull also has a curved configuration transversely of the longitudinal axis providing alternating convex and concave surfaces so that the bottom acts a hollow arch. The deck is formed integrally with the hull and the bulkhead partitions and is curved transversely to the longitudinal axis with its upper surface being convex. Steel concrete or prestressed concrete can be used in forming the monolithic ship's body.