An extendable hull system movable between a mono-hull to a multi-hull configuration is provided so as to take advantage of both types of hull designs depending on the boating conditions. The extendable hull system provides a center hull portion and two side hull portions, each with separate planing surfaces in an expanded multi-hull configuration, and providing a shared planing surface in the contracted mono-hull configuration. The extendable hull system provides a pivotably connected railing system along a periphery of the side hull portions for moving to a deployed configuration providing additional walking surface. The extendable hull system provides a retractable awning movable between positions for covering the mono-hull and the multi-hull configuration.

An internal canoe frame acts as a mount for retractable outriggers, foldable panels, and pontoons. With the outriggers, panels, and pontoons, the canoe can be adapted to provide a stable multi-purpose waterborne platform. In some embodiments, the platform may also include a support frame for a tent, to provide a waterborne camping site for an intrepid canoer.

A marine vessel comprising: at least one buoyant tubular foil; and at least one baffle plate positioned about the perimeter of the at least one buoyant tubular foil so as to protrude into the flow of water passing by the perimeter of the at least one buoyant tubular foil, whereby to create a high-pressure zone fore of the at least one baffle plate and a low-pressure zone immediately aft of the at least one baffle plate, whereby to create a dense stream of supercavitated water immediately aft of the at least one baffle plate.

Disclosed is a wave amplification power-generating boat, comprising float systems (1), a support system (2), a hydraulic turbine power-generating system (3) or a float power-generating system (7) or a canard-type power-generating system (8), a wind rudder system (4), a propeller (5), a mooring system (6) and a wave detector system (9). The float systems (1) are capable of moving on a support; the support system (2) is used to connect the float systems (1) at two ends, with the hydraulic turbine power-generating system (3) or the float power-generating system (7) or the canard-type power-generating system (8) installed in the middle, and installing the wind rudder system (4), the propeller (5), the mooring system (6), and the wave detector system (9); the hydraulic turbine power-generating system (3), etc., works and generates power by utilizing amplified waves in the middle of a boat; and the wave detector system (9) is used to detect and compute an average wave length, to adjust in a timely manner a distance between floating points (101) at two ends to be as close to the wave length as possible, and adjust the direction of the boat to be consistent with that of the wave. The wave amplification power-generating boat enables a high wave energy conversion efficiency, and has a very strong ability to wind and waves.

An internal canoe frame acts as a mount for retractable outriggers, foldable panels, and pontoons. With the outriggers, panels, and pontoons, the canoe can be adapted to provide a stable multi-purpose waterborne platform. In some embodiments, the platform may also include a support frame for a tent, to provide a waterborne camping site for an intrepid canoer.

A boat hull comprises a central hull having top and bottom portions and first and second side hulls slidably supported from the top portion of the central hull so as to be transversely extendable relative thereto. The bottom portion of the central hull is rotatably connected to the top portion so as to be movable between raised and lowered positions. A method of reconfiguring the boat hull comprises slidably displacing first and second side hulls relative to a central hull and rotatably displacing a bottom portion of the central hull relative to a top portion from a raised position to a lowered position between the first and second side hulls.

A water craft comprising: an elongated hull comprising a passageway having an inlet and an outlet; a pump jet disposed within said passageway intermediate said inlet and said outlet; said pump jet being configured to receive water entering said passageway through said inlet and pump said water out of said outlet, whereby to propel said hull through water; a plurality of nozzles disposed on the outer surface of said hull, aft of said inlet, wherein said plurality of nozzles are configured to release a friction-reducing fluid, whereby the friction-reducing fluid displaces water from the surface of said hull so as to diminish friction on the outer surface of said hull and facilitate high speeds.

A suspension system for a marine vessel, the marine vessel including a body portion at least partially supported relative to at least a left hull and a right hull by the suspension system, the left and right hulls being moveable relative to each other and the body, the suspension system including resilient supports between the body portion and the left and right hulls. The suspension system providing at least a roll stiffness being arranged to provide a roll moment distribution (RMD) of the suspension system wherein roll forces effectively act at a position disposed within a longitudinal distance along the marine vessel from a steady state position of the resultant pressure forces acting on the left and right hulls when the marine vessel is operating in a planing or semi-planing mode. The longitudinal distance can be 20% or less of a waterline length of one of the at least a left and a right hull at design load in displacement mode.

An expandable and contractible boat comprises a first outer hull and a second outer hull symmetrically shaped and arranged with respect to one another. The first and second outer hulls are movable relative to one another, and each of the first and second outer hulls includes an outboard side portion, an inboard side portion, a bottom portion between the outboard side portion and the inboard side portion, and a concave chine portion connecting the outboard side portion and the bottom portion. A cross-section of each of the first and second outer hulls is recessed at the concave chine portion.

An extendable and retractable lower deck is supported by one or more longitudinally extending hulls. The lower deck slides between an extended position and a stowed position on rails that are secured to the underside of an upper deck of a houseboat, pontoon boat, tritoon boat, catamaran, floating dock, pier-supported dock or other watercraft or dock. When fully extended, the floating deck remains attached to the watercraft, and additional width may be achieved with laterally expandable panels in the lower deck. Various accessories are connected to the lower deck or to a storage hold in the hull beneath the lower deck, such as a pool liner insert, a hot tub liner insert, a slide and ladder assembly, a seat and mounting bracket assembly, a volleyball net and pole assembly, an umbrella and pole assembly, a hammock and stand assembly, a seat lift, and an expandable deck insert.