Abstract: The invention describes a method of nuclear energy transformation into electric and/or mechanical energy by triggering criticality in a working cylinder by an approach of a piston with a neutron reflector layer to fissile heat elements. Optionally, liquid moderator should fill the heating element to provide for an additional condition of such triggering. The pulse reaction initiates a heat cycle by expanding working fluid, extracting mechanical work and compressing the working fluid using lower amount of energy. The energy released in reaction can drive a column of water as a liquid piston propelling a highly efficient hydraulic turbine and producing a simple economical method of energy conversion. The piston movements can also be converted in laser and electromagnetic pulses. Self-regulation of nuclear reaction by a reflector piston linked to a resilient spring can be used in marine propulsion.

Abstract: An electrical linear motor for propelling a marine vessel through a liquid medium, comprises a housing secured to the marine vessel and submerged in the liquid medium, an insert within the housing and having at least two electrical coil windings disposed on internal walls of the insert; a thruster subassembly moves between the internal walls of the insert, the thruster subassembly having a front cover, an internal channel with check valve and at least two sets of permanent magnets attached to the thruster subassembly and maintained in sufficiently close proximity to the electrical coil windings so that an electromagnetic field created by a controlled energizing of the electrical coil windings interacts with a magnetic field from the permanent magnets to provide a resulting linear force, which causes a reciprocating linear motion of the thruster subassembly, wherein the check valve is in an open position during a back stroke of the thruster subassembly so that the liquid medium flows freely through the thruste

Abstract: An electrical linear motor for propelling a marine vessel comprises a thruster assembly disposed within a guide tube. Permanent magnets are attached to the thruster assembly and placed in close proximity to electrical coil windings, which are positioned outside of and parallel to the guide tube. Electrical current energizing the coil windings creates an electromagnetic field, which interacts with the magnetic field of the magnets to cause reciprocating linear motion of the thruster assembly with the guide tube. During the non-propelling back stroke, a check valve on the thruster assembly is in open position to allow free passage of water. The check valve is moved to a closed position during the working stroke of the thruster assembly, allowing the thruster assembly to propel the marine vessel.

Abstract: A method and apparatus is disclosed for producing propulsion underwater with minimal acoustical emission. In basic concept, the method comprises the expulsion and sucking of liquid into and out of a liquid port of a watercraft in a manner generating compression and expansion waves adjacent the liquid port. Such expansion and compression waves generate a positive net thrust on the watercraft in a direction opposite that of their expulsion. A reciprocating member and an actuator are also disclosed for generating the forces and energy necessary to create the expansion and compression waves.

Abstract: An aquatic sports device which includes a buoyant body and a water injection device. The water injection device includes a tank, a piston, and a spring. In operation, the user's weight drives the piston downwardly. This causes water to spray out from the buoyant body through a nozzle. The reaction of the sprayed water makes the device move forward through a body of water. The spring returns the piston upwardly when the user takes his or her weight off of the piston.

Abstract: A reciprocating marine propulsion engine is disclosed which includes a hollow, propulsion cylinder with a cylindrical axis, an intake end for admitting ambient water and an opposed discharge end for discharging water. A reciprocating shaft coaxial with the propulsion cylinder, transmits a reciprocating drive force. A ring member is mounted perpendicularly on a first end of the shaft and slideably engages the interior surface of the propulsion cylinder. Two semicircular vanes of a butterfly valve are pivotally mounted on the ring member for movement about an axis perpendicular to the cylindrical axis. A hollow ram cylinder has a first end mounted to and coaxial with the intake end of the propulsion cylinder, with a ram piston mounted on a second end of the shaft which slideably engages the interior surface of the ram cylinder.

Abstract: A boat having an external float pivotally fixed to the boat. Through linkage, the motion of the float relative to the boat resulting from wave motion drives a dual cylinder pump. The pump admits water from the body of water in which the boat is suspended and pressurizes that water for direction aft as a means for propulsion.