A submersible vessel comprising: an elongated hull; at least one propeller mounted on a forward end of said hull and adapted to move said hull through water; said at least one propeller being of a size and configuration such that when it is rotated at an appropriate speed, it generates supercavitated water flowing from said at least one propeller and thence along an outer surface of said hull so as to diminish friction on the outer surface of said hull and facilitate high underwater speeds.

A marine engine propelling apparatus (10) is mounted to an outboard portion at a rear end of a boat. The engine propelling apparatus (10) has a power generating portion (13), a power transmitting portion (17) provided below the power generating portion (13), a propelling force generating portion (28) provided below the power transmitting portion (17), and a height adjustment mechanism (25). The power generating portion (13) includes an engine (11) equipped with a crankshaft (11C), and the crankshaft (11C) is arranged substantially parallel to a front-rear direction of the boat and is substantially horizontal. The power transmitting portion (17) has a power transmission mechanism forming a linear power transmission route (D2) extending from the vicinity of a front end of the crankshaft (11C) to the vicinity of a front end of the propelling force generating portion (28). The propelling force generating portion (28) includes a propeller shaft (22) extending rearwards from the power transmitting portion (17), and a propeller (27) provided at a rear portion of the propeller shaft (22). The height adjustment mechanism (25) is configured to vary inclination of a part of the propeller shaft (22) with respect to the boat to thereby vary height of the propeller (27) with respect to the boat.

One embodiment of submerged blades (101) that provide hydrodynamic force to a vessel or aircraft (117) that can lift it above the surface of the water (106) at high speed by creating thrust with a single wetted high pressure surface (111), the low pressure surface (112) being covered with a gas filled void in the liquid, thus preventing sudden loss of lift as speed increases due to cavitation or surface venting. Other embodiments are described and shown.

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.

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.

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