Abstract: An improved thrust director unit is provided for discharging a directionally adjustable water jet flow from the hull of a marine vessel to generate a thrust reaction force for close-quarter maneuvering and/or propulsion of the vessel. The unit comprises a thruster housing having an outlet through which the jet flow is discharged, wherein the outlet is defined by diverging fore and aft walls to permit angularly forward or rearward jet flow discharge for vessel propulsion. At least two deflector vanes are movable together within the housing outlet and cooperate therewith to define a directionally adjustable discharge flow path for selective jet flow discharge in a sideward direction to produce a sideward thrust, or in a forwardly or rearwardly angled direction to respectively produce a reverse or forward propulsion thrust. In the sideward thrust position, the discharge flow path has a nondiverging cross section and is isolated from the diverging fore-aft walls of the housing outlet.

Abstract: An improved thruster system is provided for maneuvering and/or propulsion of a marine vessel, through the use of directionally oriented water jets discharged tangentially from a helical-conical flow chamber. The thruster system includes a high capacity pump for pumping water through a hull intake to the flow chamber with a substantial helical or swirling action. The water exits the flow chamber through one or more of a plurality of tangentially oriented discharge conduits having discharge nozzles for passage of high velocity water jets through the hull, resulting in reaction forces used to maneuver or propel the vessel. Each discharge conduit includes a valve member movable between open and closed positions for respectively permitting or preventing water flow to the associated nozzle.

Abstract: An ice lubrication system for easing the passage of a ship through ice laden waters. A pressurized flow of water passes through a nozzle into the inlet of a mixing chamber comprising a venturi where gas from a gas manifold is mixed with the water. The effect of the venturi is to first cause the gas to mix into the water flow and, after passage of the flow through the venturi, to cause the gas to emerge from the water. A frothy combination of gas bubbles and water is thus created which is discharged through openings in the ship's hull below the waterline. Once discharged, the gas and water combination rises up the side of the hull to provide separation and lubrication between the hull and floating ice.

Abstract: An ice lubrication system for easing the passage of a ship through ice laden waters. A pressurized flow of water passes through a nozzle into the inlet of a mixing chamber comprising a venturi where gas from a gas manifold is mixed with the water. The effect of the venturi is to first cause the gas to mix into the water flow and, after passage of the flow through the venturi, to cause the gas to emerge from the water. A frothy combination of gas bubbles and water is thus created which is discharged through openings in the ship's hull below the waterline. Once discharged, the gas and water combination rises up the side of the hull to provide separation and lubrication betwen the hull and floating ice.

Abstract: An improved boat thruster system including a pump for drawing water through an inlet in the boat hull and for discharging water through first and second pipes connected to outlets located on either side of the hull. A valve is installed in each of the pipes to control the flow of water therethrough. The valves may be controlled by either an open or closed loop control system configured so as to prevent both outlet pipes from being closed at the same time during system operation. Each valve is preferably comprised of multiple vanes each of which is mounted for rotation about an off center axis such that in the event of a valve control system failure, the water flow will cause the valve to open rather than close thereby preventing undesirable high pressure buildup in the system.

Abstract: An improved boat thruster system including a pump for drawing water through an inlet in the boat hull and for discharging water through outlets on both sides of the hull. The improved system includes a plurality of substantially planar vanes mounted in the water flow path proximate to said outlets. The vanes function to reduce swirl angle components in the water flow and thus increase thrust efficiency and to prevent the ingestion of water borne debris into the outlets.