The invention relates to a hydrofoil system for a marine vessel comprising a hull (101), the hydrofoil system comprising at least one pair of foldable hydrofoils (109, 110) which are pivoted relative to the marine vessel, wherein each hydrofoil (109, 110) is controllable by at least one actuator (930) for displacement of the at least one pair of foldable hydrofoils in a lateral direction of the marine vessel between a stowed position and a deployed position. Each foldable hydrofoil (109, 110) is hinged relative to the hull above the water line on opposite sides of the marine vessel. A first portion (111) of each hydrofoil extends adjacent the hull (101) towards the water line of the marine vessel when the hydrofoil is in the stowed position and a second portion (112) comprises a free second end extending under the hull. The second portion (112) is submerged and arranged in a lateral recess (107) behind a stepped hull portion (106) of the marine vessel when the hydrofoil is in the stowed position.

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.

A steering system for a hydrofoil watercraft, wherein a user may ride in a seated, prone, kneeling, or standing position while steering the watercraft without the use of his or her bodyweight. Vertical elevation, left and right roll, and longitudinal direction control of the watercraft is accomplished via steering, resulting in movement of the control surfaces (fins) on the hydrofoil, thus eliminating the need for weight shifting on the flotation device. An electronic remote and/or mounted joystick steering system can be operated either electronically or through direct mechanical linkage to control the direction of the watercraft. The steering system can include an unmanned remote controlled drone hydrofoil watercraft that can be operated remotely.

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 watercraft system is provided. The watercraft system includes a lifting body designed to generate dynamic lift during watercraft operation. The lifting body is shaped with a twist from the center to the lateral edges and with a chord and a fore-aft cross-section that both decrease from a center of the lifting body to lateral tips of the lifting body.

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.

Systems, apparatus, and methods for hydrofoil assemblies with planing blades that may be adjusted, and securely maintained in varying tilts with respect to a support member, using a curved indexing system with a curved ridge and a counterpart groove that utilize interacting position retaining elements to retain a desired tilt in different adjustable positions. In one illustrative system, a planing blade may have a convexly curved ridge disposed on a surface thereof with a series of transverse grooves disposed in the curved ridge. A support member may have a counterpart concavely curved receiver with a series of counterpart transverse grooves formed therein. When a user places the planing blade in position with the convex ridge contacting the concave receiver, the blade may be tilted to a desired position. The counterpart transverse grooves interconnect to provide an indexed positive interlock, securely maintaining the blade in the desired position.

Systems, devices, and methods are provided for operating a watercraft vessel. The system can include a communication unit configured to receive a position signal and a velocity signal of the first vessel. The system can include a first sensing unit configured to determine a relative position signal of one or more nearby vessels including the first vessel, a second sensing unit configured to detect and measure a fluid velocity field of a vortex around the watercraft vessel, and a third sensing unit configured to detect and measure an efficiency gain from a lifting force experienced by watercraft vessel operating in an upwash region of the vortex. And the system can include a control unit configured to maneuver the watercraft vessel from a first position to an optimum position.

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 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.