Abstract: A device for insertion in watercraft including propulsion means comprising a pair of flappers which oscillate through an arcuate path in a transverse direction with respect to the central longitudinal dimension of the watercraft. As input force is applied, the flappers twist to form an angle of attack for providing forward thrust. The means for applying propulsive force includes a pair of pedals, and further includes pedal cranks operatively associated with the propulsion means, the fore ends of the pedals being pivotally attached to a fixed point.

Abstract: A human propelled watercraft having a pair of flexible fins extending into the water each adapted to oscillate through an arcuate path in a generally transverse direction with respect to the central longitudinal dimension of said watercraft. Pedals are provided for applying input force whereby as input force is applied, the flexible fins can twist to form an angle of attack for providing forward thrust with respect to the longitudinal dimension of the watercraft while moving in both directions along the arcuate path. The user can pull a lever and cause the fins to rotate 180° and produce thrust in the reverse direction. The fins are able to pivot and swing aft to avoid damage if there is a collision with a submerged object. The fins are more efficient, durable, and adjustable. Simple plastic roller bearings have been adapted to reduce mechanical friction without the need for oil seals.

Abstract: A human propelled watercraft having a pair of flexible fins extending into the water each adapted to oscillate through an arcuate path in a generally transverse direction with respect to the central longitudinal dimension of said watercraft. Pedals are provided for applying input force whereby as input force is applied, the flexible fins can twist to form an angle of attack for providing forward thrust with respect to the longitudinal dimension of the watercraft while moving in both directions along the arcuate path. The user can pull a lever and cause the fins to rotate 180° and produce thrust in the reverse direction. The fins are able to pivot and swing aft to avoid damage if there is a collision with a submerged object. The fins are more efficient, durable, and adjustable. Simple plastic roller bearings have been adapted to reduce mechanical friction without the need for oil seals.

Abstract: A wind powered craft carrying a generally vertical mast which is rotatable about its vertical axis, having a sail carried by the mast with its bottom edge attached in proximity to the bottom of the mast and extending to an attachment point in proximity to the top of the mast. A generally horseshoe-shaped member having an open end is and extending around said mast. The mast being rotatable within the horseshoe-shaped member. A bearing supported stationary member at the top of the mast is carried by the mast while allowing the mast to rotate. A support stay runs from the horseshoe-shaped member to the bearing supported member to support the horseshoe-shaped member. Additional stays are attached to the horseshoe-shaped member and splayed to attach to opposed sides of the hull of the watercraft. The sail is reefed around the mast through the open end of the horseshoe-shaped member.

Abstract: A watercraft having a seat securely carried on the watercraft, the seat having a plastic seat frame and a plastic seat back frame. The seat frame and the seat back frame are joined via a hinged connection. The bottom of the seat frame has receptacles that easily engage with engagement elements mounted on the deck of the watercraft. The seat has mechanism to easily adjust the height of the front of the seat, the height of the rear of the seat, the recline angle, and the amount of lumbar support. The seat has four legs stored under the seat frame which can be plugged into the seat frame to turn the seat into a lawnchair.

Abstract: The invention relates to a watercraft mounting system that embodies a multi-faceted tube and a mating clamp system adapted to carry an accessory. The designs of the railing and clamp have geometry to prevent rotation while allowing flexibility of adjustment in multiple positions.

Abstract: A wind powered craft carrying a generally vertical mast which is rotatable about its vertical axis, having a sail carried by the mast with its bottom edge attached in proximity to the bottom of the mast and extending to an attachment point in proximity to the top of the mast. A generally horseshoe-shaped member having an open end is and extending around said mast. The mast being rotatable within the horseshoe-shaped member. A bearing supported stationary member at the top of the mast is carried by the mast while allowing the mast to rotate. A support stay runs from the horseshoe-shaped member to the bearing supported member to support the horseshoe-shaped member. Additional stays are attached to the horseshoe-shaped member and splayed to attach to opposed sides of the hull of the watercraft. The sail is reefed around the mast through the open end of the horseshoe-shaped member.

Abstract: A device for insertion in watercraft including propulsion means comprising a pair of flappers which oscillate through an arcuate path in a transverse direction with respect to the central longitudinal dimension of the watercraft. As input force is applied, the flappers twist to form an angle of attack for providing forward thrust. The means for applying propulsive force includes a pair of pedals, and further includes pedal cranks operatively associated with the propulsion means, the fore ends of the pedals being pivotally attached to a fixed point.

Abstract: A watercraft having a chair with seat securely carried on the watercraft, the chair having a tubular frame comprising a seat frame, a back frame, and arms above and at each side of the seat frame. The seat and back frames are joined via a hinged connection. The front support legs extend downwardly from the front of each of the arms and terminate in a foot-like projection. A U-shaped rear chair support having downwardly extending portions at the rear of each of the arms, which are joined at their lower extremity by a horizontal portion. The surface of the watercraft has adhered thereto two spaced apart shoes for receiving the feet.

Abstract: A remote powered propulsive device having a rudder which carries a propeller or oscillating fins which are powered by pedals alone or with hydraulic assist or by an electric motor.

Abstract: A human propelled watercraft having a pair of flexible fins extending into the water each adapted to oscillate through an arcuate path in a generally transverse direction with respect to the central longitudinal dimension of said watercraft. Pedals are provided for applying input force whereby as input force is applied, the flexible fins can twist to form an angle of attack for providing forward thrust with respect to the longitudinal dimension of the watercraft while moving in both directions along the arcuate path. The user can pull a lever and cause the fins to rotate 180° and produce thrust in the reverse direction. The fins are able to pivot and swing aft to avoid damage if there is a collision with a submerged object. The fins are more efficient, durable, and adjustable. Simple plastic roller bearings have been adapted to reduce mechanical friction without the need for oil seals.

Abstract: A watercraft having a hull, a mast with sail, an aft rudder and a hydrofoil projecting below the bottom of the hull. The hydrofoil is pivotly connected to the hull enabling the hydrofoil to pitch on a pivot axis which is essentially perpendicular to the longitudinal axis of the hull. The hydrofoils have a vertical part which produces lateral forces to accelerate the boat in turns and resist lateral forces from the sail, and a vertical portion which curves into the horizontal portion which produces vertical lift. The angle of incidence of the hydrofoil is controlled by a sensor arm carrying a trailing sensor.

Abstract: A watercraft having a chair with seat securely carried on the watercraft, the chair having a tubular frame comprising a seat frame, a back frame, and arms above and at each side of the seat frame. The seat and back frames are joined via a hinged connection. The front support legs extend downwardly from the front of each of the arms and terminate in a foot-like projection. A U-shaped rear chair support having downwardly extending portions at the rear of each of the arms, which are joined at their lower extremity by a horizontal portion. The surface of the watercraft has adhered thereto two spaced apart shoes for receiving the feet.

Abstract: A novel hatch and with cover for boats comprising: a hatch, a hatch cover with handle hinged to said hatch, and cooperating means on the hatch and cover including cam surfaces whereby the said handle can be rotated to secure the cover to the hatch.

Abstract: A watercraft having a hull, a mast with sail, an aft rudder and a hydrofoil projecting below the bottom of the hull. The hydrofoil is pivotly connected to the hull enabling the hydrofoil to pitch on a pivot axis which is essentially perpendicular to the longitudinal axis of the hull. The hydrofoils have a vertical part which produces lateral forces to accelerate the boat in turns and resist lateral forces from the sail, and a vertical portion which curves into the horizontal portion which produces vertical lift. The angle of incidence of the hydrofoil is controlled by a sensor arm carrying a trailing sensor.

Abstract: An air inflatable watercraft, having a cockpit with a bottom area forming part of the cockpit having a through opening therein adapted to receive a human operated propulsion mechanism which can be operated from the cockpit to propel the watercraft.

Abstract: A remote powered propulsive device having a rudder which carries a propeller or oscillating fins which are powered by pedals alone or with hydraulic assist or by an electric motor.

Abstract: An air inflatable watercraft, preferably having a bow and stern, and having a cockpit, a bottom area forming part of said cockpit having a through opening therein adapted to receive a human operated propulsion mechanism which can be operated from the cockpit to propel the watercraft. An air inflatable watercraft having an inflatable, airtight bow and stern, and having a bottom area between two side inflatable, airtight compartments which run essentially the length of the watercraft, upon inflation the two side compartments at least partially extend above the bottom to provide a cockpit therebetween, and the inflated bow and stern form a configuration which is adapted to be efficiently propelled, viz., adapted to cut through the water. This embodiment can be hand rowed or provided with a pedaled propulsion mechanism provided a through opening is built into the bottom.

Abstract: A retraction system for rudders for small boats having a deck comprising a rudder means connecting said rudder to the rear of a boat enabling said rudder to pivot on an axis such that when the rudder is retracted, it rotates upwardly through about 270° from the normal operating position in the water while twisting about 90° so as to lay essentially flat on said deck.

Abstract: A novel hatch and with cover for boats comprising: a hatch, a hatch cover with handle hinged to said hatch, and cooperating means on the hatch and cover including cam surfaces whereby the said handle can be rotated to secure the cover to the hatch.