An aeration control system and method for a marine vessel. The system includes a valve configured to be coupled to an aeration conduit of a marine vessel. The valve is configured to be responsive to a valve control signal having a first value so as to be open and to provide air to the aeration conduit, and the valve configured to be responsive to the valve control signal having a second value so as to be closed and not provide air to the aeration conduit. The aeration control system also includes a control device, electrically coupled to the valve, that provides the valve control signal to the valve

An engine propelling apparatus has power generating transmitting portion provided below a power generating portion, a propelling force generating portion provided adjacent to the power transmitting portion, and height adjustment mechanisms. The power generating portion includes an engine with a crankshaft arranged horizontal and substantially parallel to the front-rear longitudinal direction of a boat. A power transmission mechanism forms a linear power transmission route extending from the vicinity of a front end of the crankshaft to the vicinity of a front end of the propelling force generating portion. The propelling force generating portion includes a propeller shaft extending rearwards from the power transmitting portion, and a propeller at a rear portion of the propeller shaft. The height adjustment mechanisms vary inclination or height of all or a part of the engine propelling apparatus with respect to the boat to thereby vary height of the propeller with respect to the boat.

An apparatus and method for use with a marine vessel having a first steerable propeller and a second steerable propeller is disclosed. The apparatus and method providing for movement of the first and second steerable propellers relative to each other and also maintains a minimum distance between the first and second steerable propellers so as to prevent the first and second steerable from contacting each other. Also disclosed is a control system and method to control the first steerable propeller and the second steerable propeller to provide the fixed distance between the first and second steerable propellers and so as to individually control the first steerable propeller and the second steerable propellers to allow the first steerable propeller and the second steerable propeller to move relative to each other.

This invention is directed toward a propeller with one of more propeller blades. The propeller blades have some combination of a sharpened leading edge, one or more steps on the upper or lower surface of the propeller blade, and an S shape. The combination of these radical changes from traditional propeller design creates a quieter, more efficient propeller that has applications on any device that uses propellers: from quadcopters and airplanes to boats and fans. Propellers with one, two, three, four, five and more propeller blades are contemplated depending upon the substance the propeller is intended for use in.

A propeller propulsion system for a watercraft includes at least one electric motor and a propeller which can be driven by the electric motor. The propeller is a surface piercing propeller. The propulsion system includes a box-like body having a side wall on which the electric motor is fixed and a cover part on which an outdrive of the surface piercing propeller is applied. The side wall and the cover part include holes through which a shaft of the motor and a shaft of the outdrive respectively pass. The box-like body includes means for transmission of motion from the drive shaft to the outdrive shaft, and the propulsion system includes means for fixing the box-like body to a transom of the watercraft.

A device includes a hub and a blade. The hub has a cylindrical geometry. The blade extends radially from the hub. The blade has a helical structure. The blade includes a leading edge, a winglet, a trailing edge, and a trough. The leading edge is formed on the blade and has an arcuate geometry. The winglet of the blade is distal relative to the hub. The winglet angles away from a surface of the blade. The trailing edge is formed on the blade to be opposite the leading edge. At least a portion of the trailing edge forms a pitch-line cup that is angled with respect to the surface of the blade. The trough is formed in a transition between the pitch-line cup of the trailing edge and the winglet. The trough forms a recess that is relatively closer to the surface of the blade.

An aeration control system and method for a marine vessel. The system includes a valve configured to be coupled to an aeration conduit of a marine vessel. The valve is configured to be responsive to a valve control signal having a first value so as to be open and to provide air to the aeration conduit, and the valve configured to be responsive to the valve control signal having a second value so as to be closed and not provide air to the aeration conduit. The aeration control system also includes a control device, electrically coupled to the valve, that provides the valve control signal to the valve

An apparatus and method for use with a marine vessel having a first steerable propeller and a second steerable propeller is disclosed. The apparatus and method providing for movement of the first and second steerable propellers relative to each other and also maintains a minimum distance between the first and second steerable propellers so as to prevent the first and second steerable from contacting each other. Also disclosed is a control system and method to control the first steerable propeller and the second steerable propeller to provide the fixed distance between the first and second steerable propellers and so as to individually control the first steerable propeller and the second steerable propellers to allow the first steerable propeller and the second steerable propeller to move relative to each other.

The purpose of the present invention is to provide a boat capable of obtaining a propulsion force in a discretionary direction. A boat is provided with Arneson drives which drive propellers by means of propeller shafts via universal joints, and which control the left and right directions of the propellers by means of hydraulic cylinders. Two of the Arneson drives are provided, and the Arneson drives are respectively provided to the left and right sides of a hull. The propellers are controlled in the left and right directions in a mutually independent manner.

This invention provides a water craft hull having an air chamber, wherein the sidewalls of the air chamber extend lower than the fore wall and the aft wall of the air chamber, and wherein the hull comprises at least one air injector configured to deliver pressurized air to the air chamber. Optionally, a hull of the invention has a high aspect ratio air chamber defined by a stable fore wall, a stable aft wall, and stable sidewalls, is a non-planing hull, has a wave-piercing bow, and has elongated keel fins (e.g. inner keel fins and/or outer keel fins). Optionally, the air chamber is configured for recirculating air flow.