Abstract: The invention provides a water jet system with higher efficiency and better steering. The water jet system uses cantilever bars for an inlet grating, to prevent blockage. The water jet system also uses an elliptical impeller shaft housing to reduce turbulence and snagging of debris by the rotating impeller shaft. The water jet system uses impeller blades with a curved cross section that curves towards the direction of forward rotation. The water jet system uses U-shaped flanges mounted to the outlet of the water jet to provide steering.

Abstract: The invention is directed to a flow energizing system for turbomachinery including means for forming a plurality of rotating jet-sheet blades upstream of an impeller and a component for circumferentially varying the blade geometries of the plurality of rotating jet-sheet blades. The a component for forming a plurality of rotating jet-sheet blades includes: impeller shroud 26 having upstream-projecting axial extension 28 attached coaxially with and projecting upstream of shroud 26; recirculation chamber 30 surrounding shroud and axial extension, 26 and 28; recirculation flow inlet 32 formed by a gap between housing 12 and downstream ends, 20a and 26a, respectively, of impeller 20 and shroud 26, for allowing backflow to pressurize recirculation chamber 30; and a plurality of generally axially-extending jet-sheet slots 34 circumferentially distributed around a periphery of axial extension 28 and passing therethrough.

Abstract: A hull extension is attached at an appropriate distance above the hull bottom surface to the stern of a planing water craft so as to be at least partially submerged at subplaning speeds and totally unsubmerged at planing speeds, effectively increasing hull length at subplaning speeds while not affecting hull length at planing speeds. A "step" effect is thus featured whereby the hull extension is not in contact with the water once planing commences. Hydrodynamic and buoyant efficiency is increased by the hull extension at subplaning speeds and unaffected thereby at planing speeds. The hull extension also offers practical utility in terms of providing additional protection, deck space and mounting area.

Abstract: Multiple flat-plate blade rows of pitch adjustable blades are offset mounted in a manner such that when flat-plate blades in adjacent rows are aligned at a specific pitch setting, respective flat-plate blades of the adjacent rows nearly mate. The offset between the flat-plate blade rows functions to produce unequal pitch angle settings of the blades of adjacent rows which, in turn, function to produce the result that the respective flat-plate blades which nearly mate, in combination, produce a blade configuration which has an effective camber.

Abstract: A waterjet propulsion system having a transversely mounted engine driving one or more pumps with multiple inlets located so that at low speed, subplaning operations a greater flow of water is available, but at higher, planing speeds some inlets vent and a reduced flow is delivered to the pumps. This is accomplished by locating some inlets between the subplaning waterline and the planing waterline of the vehicle.

Abstract: A water jet propulsion system of improved efficiency with a novel boundary ayer water inlet, and having multiple water jet pumps and motors. The inlet has a large width to height ratio. The pumps may be connected to one drive shaft which can be connected to one or more motors by means of clutches.

Abstract: A waterjet propulsion system having at least two pumps in series so that low from a hull or other intake is directed through a first waterjet propulsion pump; and then via a two-position diverter valve, either out to a thrust nozzle, or to and through a second waterjet propulsion pump having a thrust nozzle. Subsequent series-pump units and diverter valves may follow to provide as many propulsion stages as required for power requirements. Each pump unit is driven by its own power unit which may be shut down when flow is diverted to the preceding unit's thrust nozzle. Good efficiencies are thereby attained over a wide range of power and speed requirements.