A linear drive system adapted for repetitive driving using a linear motor. The drive system may be used to power pumping hydrofoils which drive a boat or ship. Linkages are used to maintain the driven portion in linear motion. A coupled dual drive system in which two driven portions are coupled such that their coupled motions travel at the same velocity in opposed directions. The coupled linear drive system which may be used as a mechanical power source for drive systems used in transportation and industry. A boat with dual pumping hydrofoils adapted for propel a boat using the hydrofoils for both lift and propulsion.

Safety strut assembly (9) for a hydrofoil craft (1) comprising a strut (12), which is attached to the hull (10) of the craft by means of a transverse oriented strut axle (40) for pivotal movement with respect to the hull, the assembly further comprising: a control rod (33) passing down through the strut (12); a linear actuator assembly (28); a hydrofoil (13) pivotally mounted to the bottom portion of the strut (12) about a transverse oriented foil axle (35); first linkage means (34) connecting the hydrofoil (13) to the control rod (33); wherein the first linkage means (34) comprises a first drive ring (48) mounted around the foil axle (35), wherein the first drive ring is provided with one first ring cam element (45), and wherein the foil axle (35) is provided with one foil axle cam element (46).

A hydrofoiling watercraft including a board for supporting a user includes a plurality of masts extending downwardly to connect one or more hydrofoil wings to the board. Examples of the watercraft include a fuselage mounted to each mast wherein a forward portion of each fuselage extends toward a direction of travel for the watercraft. A hydrofoil wing is mounted to the forward portion of each fuselage. A tail wing may be mounted to a rearward portion of the respective fuselages.

A watercraft fin that dynamically keep a neutral alignment within the range of angles a user chooses to have and/or change in respond to the flow conditions so reducing drag. Hence, this invention is such to enable a fin to rotate within a range of angles via a rotary bearing and bearing housing which are to receive a fin having a journal base. The housing is to be fitted to a watercraft such as a surfboard, the housing having a changeable circular keyway to loosely receive a shear key at the underside of the journal base as to allow free circular motion of the shear key and correspondingly the journal base and the fin within the limits of the selected circular length of the keyway. In one form the fin is fitted with a root portion adapted to be inserted into a receiving portion extending radially in the journal base and trapped within the bore of the bearing.

This disclosure extends to systems, apparatus, and methods for quick release mast mounting assemblies for board mounted hydrofoil assemblies. In one exemplary system, a quick release mounting assembly may include board mountable base receiver for mounting to a sports board, which defines a longitudinal receiving recess. A resilient locking member is disposed at a front end of the base receiver. A separate mast connection member formed as a body configured for connection to an upper end of a hydrofoil mast, corresponds to the longitudinal receiving recess, and includes a counterpart structure for forming a secure connection with the resilient locking member. The mast connection member may include opposite shoulder or wing members that extend laterally orthogonal to the longitudinal axis thereof and the receiving recess may include counterpart slots for receiving these members. The resilient locking member may include a separate spring assembly or be a unitary member.

A watercraft including a board having a top surface and a bottom surface and a hydrofoil attached to a strut. The strut attaches at the bottom surface of the board. The watercraft includes a movable portion coupled to the top surface of the board such that the movable portion is configured to move relative to a fixed portion of the board.

The present invention is directed broadly to an underwater appendage assembly (10) of a marine vessel (12). The underwater appendage assembly (10) is in the form of a rudder assembly fitted to a bow section (14) of the vessel (12). The rudder assembly comprises an appendage in the form of a rudder foil (18) connected to a flapper member (20). The flapper member (20) is arranged whereby movement and more particularly pitching, of the vessel (12) induces deflection of the flapper member (20) relative to the rudder foil (18). This deflection in the flapper member (20) provides an oscillating movement of the flapper member (20) in a flapping action which is substantially synchronised with movement of the vessel (12) upward and downward. The flapping action of the flapper member (20) is effective in promoting forward propulsion of the vessel (12).

A hydrofoil assembly adapted to be attached to a watercraft includes a mast having a mast head adapted to be removably engage with the watercraft and disposed exterior to the watercraft. The hydrofoil assembly also includes a propulsion assembly coupled to the mast and including a propeller and an electric motor for rotating the propeller. The hydrofoil assembly also includes at least one wing coupled to the mas. Moreover, the hydrofoil assembly includes a battery coupled to the mast head and adapted to be arranged exterior to the watercraft.

The invention involves a hydrofoil vessel (1) comprising a hydrofoil assembly (4), and a hull assembly (2) presenting, when the vessel is floating at rest, a vertical symmetry plane (SP), wherein the hydrofoil assembly (4) comprises two struts (401) extending from the hull assembly (2) on opposite transverse sides of the symmetry plane (SP), mainly downwards when the vessel is floating at rest, or mainly partly away from the symmetry plane and partly downwards when the vessel is floating at rest, wherein the hydrofoil assembly (4) comprises two main foil portions (411) each extending from a respective one of the struts (401), at least partly towards the symmetry plane (SP), wherein each strut (401) comprises a strut foil (402) with a non-symmetrical cross-section, and with a pressure side (402P) facing at least partly towards the symmetry plane, and a suction side (402S) facing at least partly away from the symmetry plane (SP).

A marine propulsion system includes wings with a hydrofoil shaped geometry arranged for mounting on opposite side sections of a vessel comprising at least one hull adjacent the transom. Each wing includes a first section extending downwards along the side of the hull and at least partially below the waterline in its operative position. Each wing includes a second section extending towards the central longitudinal axis of the hull in its operative position. The second section each wing is arranged to support at least one propulsor. The first section of each wing is mounted rotatable about a vertical axis.