Embodiments of the present apparatus and method feature a permanently fixed canted keel. The apparatus and method feature tacking maneuvers which shift the sail element and reverse the direction of the hull form.

Embodiments of the present apparatus and method feature a permanently fixed canted keel. The apparatus and method feature tacking maneuvers which shift the sail element and reverse the direction of the hull form.

A personal watercraft hull has a bow, a keel, starboard and port upper edges, a starboard portion extending between the keel and the starboard upper edge, a port portion extending between the keel and the starboard upper edge, and a transom. The starboard portion has a starboard row of grooves. The port portion has a port row of grooves. The rows of grooves extend in a longitudinal direction and are laterally offset from the longitudinal centerline and from their corresponding upper edge. The grooves of the rows of grooves define recesses in an outer surface of the hull. A personal watercraft having the personal watercraft hull is also disclosed.

A personal watercraft hull has a bow, a keel, starboard and port upper edges, a starboard portion extending between the keel and the starboard upper edge, a port portion extending between the keel and the starboard upper edge, and a transom. The starboard portion has a starboard row of grooves. The port portion has a port row of grooves. The rows of grooves extend in a longitudinal direction and are laterally offset from the longitudinal centerline and from their corresponding upper edge. The grooves of the rows of grooves define recesses in an outer surface of the hull. A personal watercraft having the personal watercraft hull is also disclosed.

A passively controlled fluid foil has a span; and a rigid spar extending in the spanwise direction, a cellular material and a flexible outer surface defining a profile of the outer surface of the foil and encapsulating the cellular material and the spar.

An objective of the present invention is to provide an underwater ship attachment that is used to divert air, debris, and pressure fluctuations. More specifically, the present invention discloses an anti-cavitation device (such as a diverter device) for flat-bottom boats. The air diverter has been developed to regain, enhance, and protect the operational function of propulsive and steering equipment among displacement and semi displacement hulls. As with protect items such as bottom mounted depth sounder transducers, intakes for engine or general cooling, sea chests, keel coolers, zincs, and all other underwater mounted items susceptible to air ingestion, air disturbance malfunction or debris impact.

An objective of the present invention is to provide an underwater ship attachment that is used to divert air, debris, and pressure fluctuations. More specifically, the present invention discloses an anti-cavitation device (such as a diverter device) for flat-bottom boats. The air diverter has been developed to regain, enhance, and protect the operational function of propulsive and steering equipment among displacement and semi displacement hulls. As with protect items such as bottom mounted depth sounder transducers, intakes for engine or general cooling, sea chests, keel coolers, zincs, and all other underwater mounted items susceptible to air ingestion, air disturbance malfunction or debris impact.

A multihull watercraft has at least three hulls extending longitudinally along the watercraft. The hulls at least partly define a port side tunnel and a starboard side tunnel therebetween. A port deflection device is configured to engage water in response to the watercraft leaning toward the port side when turning. The port deflection device is laterally aligned with the port side tunnel. A starboard deflection device is configured to engage water in response to the watercraft leaning toward the starboard side when turning. The starboard deflection device is laterally aligned with the starboard side tunnel. Each of the deflection devices includes an angled surface extending downwardly and rearwardly from an upper tunnel surface of a corresponding one of the tunnels. The angled surface is positioned to remain above a water line when the multihull watercraft is at rest on water.

A multihull watercraft has at least three hulls extending longitudinally along the watercraft. The hulls at least partly define a port side tunnel and a starboard side tunnel therebetween. A port deflection device is configured to engage water in response to the watercraft leaning toward the port side when turning. The port deflection device is laterally aligned with the port side tunnel. A starboard deflection device is configured to engage water in response to the watercraft leaning toward the starboard side when turning. The starboard deflection device is laterally aligned with the starboard side tunnel. Each of the deflection devices includes an angled surface extending downwardly and rearwardly from an upper tunnel surface of a corresponding one of the tunnels. The angled surface is positioned to remain above a water line when the multihull watercraft is at rest on water.

The invention relates to a floating maritime vessel including at least one hull beneath a deck, the hull extending between a bow and a stern in a longitudinal direction of the vessel, the vessel including, on its lower part, a removable keel and, on its upper part, a conning tower erected above the deck, the keel being able to be descended below the hull and raised back through the hull, the keel including a lower end and an upper end, the upper end of the keel connecting to the hull when the keel is in its lowered position. According to the invention, the conning tower contains a keel-storage space and the keel and the keel-storage space of the conning tower are aligned such that the keel can be raised by upward translation at least partly into the keel-storage space of the conning tower.