Fin arrangement for a water sports device, having a base body (1) and a fin (3) which is detachably connected or connectable to the base body (1) via a spring element (2), whereby the base body (1) has a mounting surface (21) for resting against the sliding surface (5) of the main body (4) of the water sports device, and whereby the fin (3) has a recess (24) for receiving at least part of the base body (1). The fin arrangement may be arranged on the sliding surface (5) of the main body (4) of a water sports device.

Fin arrangement for a water sports device, having a base body (1) and a fin (3) which is detachably connected or connectable to the base body (1) via a spring element (2), whereby the base body (1) has a mounting surface (21) for resting against the sliding surface (5) of the main body (4) of the water sports device, and whereby the fin (3) has a recess (24) for receiving at least part of the base body (1). The fin arrangement may be arranged on the sliding surface (5) of the main body (4) of a water sports device.

A watercraft and a waterproof electronics container are provided. The watercraft includes a flotation portion. A strut is removably affixed to a portion of the watercraft. A first connector portion is mounted to the upper end of the strut. A waterproof electronics container includes a second connector portion is disposed such that the second connector forms at least one electrically conductive pathway with the first connector portion when both are affixed to the watercraft. The waterproof electronics container is removably affixed to the said watercraft. In one aspect, the waterproof electronics container houses a power source capable of powering an electric motor that propels the watercraft.

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.

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 personal watercraft includes a floatation member, a thrust assembly, a steering assembly, and a braking assembly. The assemblies may be actuated either mechanically or electrically. The thrust assembly is human powered, solar powered, or electric powered. The thrust, steering, and braking assemblies can be added after-market to an existing stand-up paddle board (SUP), or built into one or a plurality of SUPs during initial manufacturing. When the thrust assembly is human powered, it is leg or arm powered. When the thrust assembly is leg powered, the legs can move backward and forward in a sliding motion, up and down in a stomping fashion, or move in a loop trajectory. When the thrust assembly is arm powered, the arms can move forward/backward together or separately. The thrust assembly includes one or a plurality of paddles or flippers that are positioned to the side or under the SUP.

A surfboard fin assembly for the flush incorporation into a surfboard body that allows for adjusting the depth the fin extends below the surfboard. It has a biasing means that maintains the fin in the down position yet allows upward movement upon the application of upward force such as when the fin is struck from below. The fin is perpendicularly affixed to a hinge body that is pivotally housed in an open ended fin box that is integrated into the volume of the surfboard body. A means for tensioning is releasably attached at a distal end to the hinge body and at a proximal end to the surfer's ankle. The height of the fin is adjustable through the means for tensioning and sets the performance of the surfboard to the surfer's desired level of directional control depending on their type of surfing. The fin or fin and hinge body are interchangeable with other design of fins.

A surfboard fin assembly for the flush incorporation into a surfboard body that allows for adjusting the depth the fin extends below the surfboard. It has a biasing means that maintains the fin in the down position yet allows upward movement upon the application of upward force such as when the fin is struck from below. The fin is perpendicularly affixed to a hinge body that is pivotally housed in an open ended fin box that is integrated into the volume of the surfboard body. A means for tensioning is releasably attached at a distal end to the hinge body and at a proximal end to the surfer's ankle. The height of the fin is adjustable through the means for tensioning and sets the performance of the surfboard to the surfer's desired level of directional control depending on their type of surfing. The fin or fin and hinge body are interchangeable with other design of fins.

This disclosure extends to systems, apparatus, and methods for sports board hydrofoil masts and mast-to-fuselage connection assemblies for hydrofoil sports boards. In one exemplary system, a hydrofoil mast formed as an elongated member may include a securing structure disposed in a lower region and a fuselage may include a recess into which the mast is inserted. A securing assembly may be disposed in the fuselage for actuation to secure the mast to the fuselage by interacting with the securing structure on the mast. The securing assembly may include a cam member or locking member and an actuating member. Unique hydrofoil masts constructed from composite materials having reinforcing metal members are disclosed and may be useful in the connection assemblies