A hydrofoil watercraft, in particular, a hydrofoil board is described herein. The hydrofoil board may comprise one or more of a body, a hydrofoil assembly, and/or other components. The body may have one or more of a deck surface configured to support a rider, a bottom surface opposite the deck surface, and/or other surfaces and/or features. The body may comprise a fore portion having a planing surface forming part of the bottom surface. The body may have an aft portion having an aft bottom surface forming part of the bottom surface. The fore portion may be toward a front end of the board. The aft portion may be toward a rear end of the board. An aft cross-sectional thickness between the deck surface and the aft bottom surface may be less than a fore cross-sectional thickness between the deck surface and the planing surface.

A hydrofoil watercraft, in particular, a hydrofoil board is described herein. The hydrofoil board may comprise one or more of a body, a hydrofoil assembly, and/or other components. The body may have one or more of a deck surface configured to support a rider, a bottom surface opposite the deck surface, and/or other surfaces and/or features. The body may comprise a fore portion having a planing surface forming part of the bottom surface. The body may have an aft portion having an aft bottom surface forming part of the bottom surface. The fore portion may be toward a front end of the board. The aft portion may be toward a rear end of the board. An aft cross-sectional thickness between the deck surface and the aft bottom surface may be less than a fore cross-sectional thickness between the deck surface and the planing surface.

A modular hydrofoil watercraft may include a plurality of modules which are releasably connectable to each other to when assembled form the modular hydrofoil watercraft. The modular hydrofoil watercraft when assembled may include a hull extending along a longitudinal center axis, a propulsion system that has a motor and a propelling member, a mast that extends downwardly from the hull and a hydrofoil connected to the mast.

Watersport board fins with fin retention systems and associated watersport boards and methods. A fin includes a hydrodynamic blade and a fin base extending from the hydrodynamic blade. The hydrodynamic blade defines a fin plane and includes a leading edge, a trailing edge, and a foil surface. The fin further includes a fin retention system with a selective retention system that includes a retainer and an actuator coupled to the retainer via a pivot shaft. The actuator forms a portion of the hydrodynamic blade when the selective retention system is in a locked configuration and is configured to rotate away from the fin plane when the selective retention system transitions from the locked configuration to an unlocked configuration. The retainer is configured to rotate away from the fin plane when the selective retention system transitions from the unlocked configuration to the locked configuration.

Watersport board fins with fin retention systems and associated watersport boards and methods. A fin includes a hydrodynamic blade and a fin base extending from the hydrodynamic blade. The hydrodynamic blade defines a fin plane and includes a leading edge, a trailing edge, and a foil surface. The fin further includes a fin retention system with a selective retention system that includes a retainer and an actuator coupled to the retainer via a pivot shaft. The actuator forms a portion of the hydrodynamic blade when the selective retention system is in a locked configuration and is configured to rotate away from the fin plane when the selective retention system transitions from the locked configuration to an unlocked configuration. The retainer is configured to rotate away from the fin plane when the selective retention system transitions from the unlocked configuration to the locked configuration.

Hydrofoil assemblies that can be attached to a board used for watersports are disclosed herein. A hydrofoil assembly may include, for example, a mast a coupleable to a fuselage at a lower portion of the mast and coupleable to a board at an upper portion of the mast, and front and rear wings coupleable to the fuselage. A hydrofoil mast may include, for example, first and second composite sections bonded together to form a hollow load-bearing mast structure. Leading and trailing elements made of a material that is softer than the composite mast structure may be adhered to the mast structure to complete a hydrodynamic profile of the mast.

A fin for use on a surfboard, the fin comprising: a leading edge, a trailing edge, and a base, the base comprising at least one mount for mounting the fin onto a surfboard; a first and a second outer fin surface which meet along the leading edge and the trailing edge and abut the base; and a first ridge protruding laterally from the first outer fin surface, and/or a second ridge protruding laterally from the second outer fin surface; wherein the shape and configuration of the fin creates an area of lower water pressure around and in front of the fin, as well as disrupting and/or reducing the size of trailing vortices, resulting in additional forward thrust for the board on which the fin is mounted.

A fin for use on a surfboard, the fin comprising: a leading edge, a trailing edge, and a base, the base comprising at least one mount for mounting the fin onto a surfboard; a first and a second outer fin surface which meet along the leading edge and the trailing edge and abut the base; and a first ridge protruding laterally from the first outer fin surface, and/or a second ridge protruding laterally from the second outer fin surface; wherein the shape and configuration of the fin creates an area of lower water pressure around and in front of the fin, as well as disrupting and/or reducing the size of trailing vortices, resulting in additional forward thrust for the board on which the fin is mounted.

A watersport board includes a board body, two female fasteners, a baseplate, a fin adapter, a fin and two male fasteners. The board body defines a receptacle. The female fasteners are embedded in the board body. Each female fastener has a receiving hole. The baseplate is attached underneath the board body. The baseplate has a first bore and two second bores. The fin adapter has an adapter body and an extension laterally extending from the adapter body. The adapter body passes through the first bore of the baseplate and is engaged in the receptacle of the board body, and the adapter body has a cavity. The fin has a base portion received in the cavity of the adapter body. Each male fastener has one end connected to the extension of the fin adapter, and the other end passing through the second bore of the baseplate and being engaged in the receiving hole of the female fastener.

A fin mounting assembly having a fin box and a cover plate. The fin mounting assembly has a fin box with an upper end that is substantially closed and a lower end that is open with an outer edge. An elongated recess is disposed substantially central along a first axis of the fin box that is adapted to receive and secure a base of a fin. The upper end of the fin box has a flange with an outer border. The flange has a gradually increasing wall height curvature along the first axis, beginning adjacent to the outer edge of the flange and a greatest wall height curvature at a flange central portion. The flange also has a slot cover wall that extends up and away from the flange along the first axis and positioned over the elongated recess. The slot cover wall has an increasing width thickness beginning at the outer edge of the flange that increases in width and has a largest width at a slot cover central portion. A cover plate has an outer border and is adapted to be attached to the outer edge of the fin box.