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.

A system for propelling a paddleboard or surfboard along the surface of a body of water, comprising a controller motor coupled to a propeller, a rechargeable battery, a controller which may be wearable on the wrist of a user, and a housing structure that is adapted to be attached to the fin box of a paddleboard without the need to remove the fin. The apparatus presents a low-drag profile, has a long battery life for extended range, and is able to be controlled so that user may operate the paddleboard at any desired speed, and in a forward or rearward direction, or in a controllable direction of thrust. The housing structure is adaptable to various fin box T-bolt separation distances.

A system for propelling a paddleboard or surfboard along the surface of a body of water, comprising a controller motor coupled to a propeller, a rechargeable battery, a controller which may be wearable on the wrist of a user, and a housing structure that is adapted to be attached to the fin box of a paddleboard without the need to remove the fin. The apparatus presents a low-drag profile, has a long battery life for extended range, and is able to be controlled so that user may operate the paddleboard at any desired speed, and in a forward or rearward direction, or in a controllable direction of thrust. The housing structure is adaptable to various fin box T-bolt separation distances.

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 mount for an inflatable watercraft is an apparatus used as a universal fin box that connects a variety of fins. The apparatus includes a clamp and a fin. The clamp mounts the fin into a fin box-receiving hole of an inflatable watercraft. The clamp includes a lower press, an upper press, and a length-adjustable fastener. The lower press and the upper press seal the fin box-receiving hole. The lower press and the upper press tighten together with the length-adjustable fastener. The lower press and the upper press tensionably tether to each other by the length-adjustable fastener. The apparatus further includes a fin-attachment mechanism that secures the fin into the lower press. The fin removably attaches into a fin-receiving slot of the lower press. The apparatus further includes a plurality of lower counterforts and a plurality of upper counterforts which structurally reinforce the lower press and the upper press.

A fin mount for an inflatable watercraft is an apparatus used as a universal fin box that connects a variety of fins. The apparatus includes a clamp and a fin. The clamp mounts the fin into a fin box-receiving hole of an inflatable watercraft. The clamp includes a lower press, an upper press, and a length-adjustable fastener. The lower press and the upper press seal the fin box-receiving hole. The lower press and the upper press tighten together with the length-adjustable fastener. The lower press and the upper press tensionably tether to each other by the length-adjustable fastener. The apparatus further includes a fin-attachment mechanism that secures the fin into the lower press. The fin removably attaches into a fin-receiving slot of the lower press. The apparatus further includes a plurality of lower counterforts and a plurality of upper counterforts which structurally reinforce the lower press and the upper press.

An assembly includes a fin and a fin mounting box for a water sports board. The mounting box is mounted to the board and has an outwardly facing channel formed therein. The fin includes a fin base and a body extending from the base. The fin base is shaped to be received in the channel. The channel includes channel engagement formations, and the fin base includes corresponding fin base engagement formations which engage the channel engagement formations when the fin base is inserted into the channel so as to retain the fin to the mounting box. The assembly includes a locking tab received in the channel to prevent movement of the fin base in the channel and disengagement of the corresponding channel and fin base engagement formations.

An assembly includes a fin and a fin mounting box for a water sports board. The mounting box is mounted to the board and has an outwardly facing channel formed therein. The fin includes a fin base and a body extending from the base. The fin base is shaped to be received in the channel. The channel includes channel engagement formations, and the fin base includes corresponding fin base engagement formations which engage the channel engagement formations when the fin base is inserted into the channel so as to retain the fin to the mounting box. The assembly includes a locking tab received in the channel to prevent movement of the fin base in the channel and disengagement of the corresponding channel and fin base engagement formations.

The present invention provides a board mountable system for filming underwater video. The inventive board mountable system can be mounted to the underside of water vehicles for incorporating a camera for filming from an underwater perspective. The inventive board mountable system is shaped to minimize drag as a result of the mounted camera or camera system. Embodiments of the inventive system includes a fin shaped housing for holding a camera or camera system. In certain embodiments, the fin is removably attached to the water vehicle, such as a surf board, where the fin housing can be swapped with other fins being used with the water vehicle for controlling the direction of a watersports board in motion. These embodiments of the inventive system further include a connection means for connecting the fin to the underside of a water vessel.

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.