Abstract: The invention relates to a hydrofoil system for a marine vessel comprising a hull (101), the hydrofoil system comprising at least one pair of foldable hydrofoils (109, 110) which are pivoted relative to the marine vessel, wherein each hydrofoil (109, 110) is controllable by at least one actuator (930) for displacement of the at least one pair of foldable hydrofoils in a lateral direction of the marine vessel between a stowed position and a deployed position. Each foldable hydrofoil (109, 110) is hinged relative to the hull above the water line on opposite sides of the marine vessel. A first portion (111) of each hydrofoil extends adjacent the hull (101) towards the water line of the marine vessel when the hydrofoil is in the stowed position and a second portion (112) comprises a free second end extending under the hull. The second portion (112) is submerged and arranged in a lateral recess (107) behind a stepped hull portion (106) of the marine vessel when the hydrofoil is in the stowed position.

Abstract: A water-jet propulsion unit includes a body, an impeller for moving water, the impeller disposed in an impeller tunnel, an impeller shaft for driving the impeller, a first bearing housing to support the impeller shaft on the body, and a jet nozzle for forming a water jet. The body comprises a shaft opening for the impeller, a flow duct having a first contact surface, an inlet opening, and an outlet opening, the planes of which are at an angle ? relative to each other. The impeller tunnel has a first end comprising a planar second contact surface and a second end comprising a planar third contact surface to seal the impeller tunnel between the body and the jet nozzle. The second and third planar contact surfaces of the impeller tunnel are arranged at an angle relative to each other. The impeller shaft is adapted for alternative types of installation by turning the impeller tunnel through 180° about the rotational axis of the impeller shaft.

Abstract: An improvement for inboard motor boats has a rigid exhaust conduit, a miniature rudder, and a rudder control system. The rigid conduit is provided for conduction of combustion gases exhaust outside the hull and has an aft facing outlet. The miniature rudder is pivotably mounted on the rigid conduit relative the aft facing outlet whereby combustion gases exhaust past the rudder. The rudder control system has a user interface inside the boat and has a control mechanism pivoting the rudder in response to inputs to the user interface.

Abstract: It is difficult to move forward/backward a water jet propulsion boat at very low speed through use of right and left operation elements each provided on a handle. In order to move the boat forward/backward at very low speed through a simple operation, under a state in which neutral operations have been carried out, an operation state of an engine is maintained in an idling state, and a movement position of a jet flow adjustment member including a deflector and a reverse bucket is controlled so as to adjust a difference between a “thrust generated by a forward jet flow component” and a “thrust generated by a backward jet flow component” of a jet flow divided into a forward jet flow and a backward jet flow by the jet flow adjustment member, based on an operation on a third operation element provided independently of the right and left operation elements.

Abstract: A rudder device is disclosed for a hydrojet vessel. The rudder device comprises a first mounting bracket coupled to a first hydrojet. A first rudder is coupled to the first hydrojet and the first mounting bracket. A second mounting bracket is coupled to a second hydrojet. A second rudder is coupled to the second hydrojet and the second mounting bracket. A coupling rod is pivotably coupled to the first hydrojet, the second hydrojet and a hull rudder for pivoting in alignment and in unison the first rudder with the first hydrojet and the second rudder with the second hydrojet relative to the hull rudder. The first rudder and the second rudder provide steerage to the vessel during non directional thrust absent from the first hydrojet and the second hydrojet.

Abstract: A propulsion device including a platform on which a passenger is positioned, said platform comprising an upper surface and a lower surface, and cooperating with means for collecting and distributing a pressurized fluid to a primary nozzle expelling said fluid from a fluid outlet in a given direction, said means being supplied with pressurized fluid by a fluid supply conduit, the device being characterized in that: the primary nozzle is oriented substantially from the bow to the stern of the platform; the fluid expulsion direction fits in a median plane of the platform; the fluid expulsion direction of the primary nozzle describes an angle comprised between ?10° and +45° with a longitudinal axis of the platform contained in said median plane.

Abstract: A cable apparatus is disposed between a handle and an actuator to transmit movement of the handle to the actuator. The handle includes a handle housing defining a housing chamber and an operation lever supported by the handle housing so as to be pivotable about a first axis. The cable apparatus includes a case housed in the housing chamber, a cable having a first end disposed in the case and a second end connected to the actuator, and a link lever supported by the case so as to be pivotable about a second axis. The link lever is connected to the first end of the cable in the case, and is displaceable by pivoting the operation lever.

Abstract: The invention relates to a surfboard assembly that can be controlled, comprising a surfboard (1), which has a stern and a bow and which has a standing surface for a surfer (2), a longitudinal axis (L) oriented from the stern to the bow, a drive having a thrust device, which thrust device can be pivoted in a pivoting plane along the standing surface (13), for producing left and right cornering of the surfboard assembly, and a propulsion unit, at least one sensor (18), which is integrated in the surfboard (1) and detects tilting clockwise and counterclockwise about the longitudinal axis (L) and which controls the pivoting direction of the nozzle (12) in such a way that tilting of the surfboard (1) counterclockwise about the longitudinal axis (L) pivots the nozzle (12) to the left in the pivoting plane.

Abstract: A water jet propulsion boat includes a boat body, an engine, a jet propulsion mechanism, a first accelerator operation section, a second accelerator operation section, a reverse gate, and a control section. The engine is accommodated in the boat body. The jet propulsion mechanism generates a propulsion power using a drive power from the engine. The reverse gate is arranged to move to a first position and to a second position. The boat body advances when the reverse gate is in the first position. The reverse gate reduces the propulsion power which advances the boat body when the reverse gate is in the second position. The control section is programmed to set the position of the reverse gate and a throttle opening of the engine based on an operation amount of the first accelerator operation section and an operation amount of the second accelerator operation section.

Abstract: A method for controlling a marine vessel having a first steering nozzle, a reversing deflector and at least one of a bow thruster and a second steering nozzle is disclosed. The method comprises any of the acts of inducing a net transverse thrust to the marine vessel in response to a transverse thrust component signal, without substantially inducing any forward-reverse thrust or rotational thrust to the marine vessel, or inducing a net forward-reverse thrust to the marine vessel in response to a forward-reverse thrust component signal without substantially inducing any transverse thrust or rotational thrust to the marine vessel, or inducing a net rotational thrust to the marine vessel in response to the rotational thrust component signal without substantially inducing any forward-reverse thrust or transverse thrust to the marine vessel.

Abstract: An unmanned underwater vehicle (UUV) is disclosed. The UUV includes a body and a propulsion system for propelling and orienting the UUV. The propulsion system has an inlet formed in the body that facilitates fluid being drawn into the UUV from outside the body. The propulsion system also has a duct in fluid communication with the inlet. The duct is adapted to direct the fluid along a flow path. The propulsion system further includes a pump operable with the duct to increase the velocity of the fluid. In addition, the propulsion system includes a nozzle in fluid communication with the duct to receive the fluid at the increased velocity. The nozzle is supported about a side of the body and adapted to moveably redirect fluid out of the UUV. The propulsion system provides multi-axis control of the UUV.

Abstract: A system for recapturing energy from a ship moving through the water utilizes a hydraulic turbine positioned within the ship's hull. Water pushed up from the bow of the ship is fed into a water conducting tube and used to drive the turbine. The turbine may produce electricity for powering on-board systems or may be used to augment the main propulsion system, thereby reducing energy costs for ship operations.

Abstract: A vessel propulsion apparatus includes a nozzle, a deflector, a reverse bucket, and a guide. In a state in which the reverse bucket is positioned at a closed position and the deflector is positioned at a straight drive position, the guide generates a right branch stream flowing in an obliquely forward right direction and a left branch stream flowing in an obliquely forward left direction. In a state in which the reverse bucket is positioned at the closed position and the deflector is positioned at a right side, the guide generates the left branch stream. In a state in which the reverse bucket is positioned at the closed position and the deflector is positioned at a left side, the guide generates the right branch stream.

Abstract: A system for controlling a marine vessel having first and second steering nozzles and corresponding first and second reversing buckets, comprises a processor configured to receive a first vessel control signal including at least a component corresponding to a translational thrust command in a port direction, and that is configured to provide a set of actuator control signals coupled to and control the first and second reversing buckets. The processor is configured to provide the set of actuator control signals so as to maintain the first reversing bucket substantially in a first discrete position and the second reversing bucket substantially in a second discrete position as long as the first vessel control signal includes a component corresponding to a translational thrust command in the port direction.

Abstract: The invention relates to a rudder for maneuvering a ship-like object, the rudder comprising a main rudder blade having an upstream end and a downstream end, the rudder being rotatably mountable to the ship-like object around a rotation axis that generally extends in a vertical plane. The main rudder blade extends generally upright. The rudder comprises two generally upright extending auxiliary rudder blades connected to the main rudder blade by transverse plates. At least one of the transverse plates is oriented generally obliquely upwards towards a downstream end. The transverse plates thereby follow the orientation of the flow of water below the upwards receding aft body of the ship.

Abstract: A jet propulsion unit has a water inlet, a pump body, an impeller, and a valve assembly fluidly. The valve assembly has a valve housing having an inlet fluidly connected to the pump body, a first outlet and a second outlet. A valve body is disposed in the valve housing and is movable between first and second positions. In the first position, water from a body of water flows consecutively through the water inlet, the pump body, the inlet of the valve housing, the valve housing and the first outlet of the valve housing. In the second position, water from the body of water flows consecutively through the water inlet, the pump body, the inlet of the valve housing, the valve housing, and the second outlet of the valve housing. A watercraft having the jet propulsion unit is also disclosed.

Abstract: A method for controlling a marine vessel having first and second steering nozzles and first and second trim deflectors comprises generating at least a first set of actuator control signals and a second set of actuator control signals. The first set of actuator control signals is coupled to and controls the first and second steering nozzles, and the second set of actuator control signals is coupled to and controls the first and second trim deflectors. The acts of generating and coupling the first set of actuator control signals and the second set of actuator control signals result in inducing any of a net yawing force, a net rolling force, and a net trimming force to the marine vessel without inducing any other substantial forces to the marine vessel by controlling the first and second steering nozzles and the first and second trim deflectors. Also disclosed is a system for controlling a marine vessel.

Abstract: An automatic trim system for a jet propulsion watercraft is provided. Control electronics are in communication with a steering angle sensor to monitor the steering angle of the watercraft, and evaluate a target setting for the trim taking the steering angle into consideration. Control signals are sent to an appropriate actuating device for adjusting the trim angle accordingly.

Abstract: A system for controlling a marine vessel having first and second steering nozzles and corresponding first and second reversing buckets, comprises a processor configured to receive a first vessel control signal including at least a component corresponding to a translational thrust command in a port direction, and that is configured to provide a set of actuator control signals coupled to and control the first and second reversing buckets. The processor is configured to provide the set of actuator control signals so as to maintain the first reversing bucket substantially in a first discrete position and the second reversing bucket substantially in a second discrete position as long as the first vessel control signal includes a component corresponding to a translational thrust command in the port direction.

Abstract: A rudder system that uses a dual purpose thrust operated actuator. The actuator is selectively positioned for use in an up or constant down mode. While in the up mode, the actuator uses the force of the jet pump to raise the rudders out of the water at speed, and with the actuator set in the down mode, the invention uses the force of the jet pump water to hold the rudder in the water. In an alternative embodiment, the invention includes anti-oscillating veins attached to the thrust operated actuator. In another alternative embodiment, the travel of the actuator is limited by configuring it to come into contact with a rudder stabilizer bar. Another embodiment includes providing adjustable fin positions relative to the side force stabilizer.

Abstract: A marine jet propulsion system has a jet pump, a venturi connected to the jet pump, and a steering nozzle rotationally mounted relative to the venturi about a first axis. The steering nozzle has a central longitudinal axis. The first axis intersects the central longitudinal axis. A first link has a first end rotationally mounted relative to the venturi about a second axis. The first link has a second end disposed generally rearwardly from the first end of the first link. A second link has a first end rotationally mounted to the first link about a third axis and a second end rotationally mounted to the steering nozzle about a fourth axis. The third axis intersects the second end of the first link. A steering arm is connected to the first link. The axes are generally parallel to each other. A watercraft having the jet propulsion system is also disclosed.

Abstract: An automatic trim system for a jet propulsion watercraft is provided. Control electronics are in communication with a steering angle sensor to monitor the steering angle of the watercraft, and evaluate a target setting for the trim taking the steering angle into consideration. Control signals are sent to an appropriate actuating device for adjusting the trim angle accordingly.

Abstract: A system for controlling a marine vessel having first and second steering nozzles and corresponding first and second reversing buckets, comprises a processor configured to receive a first vessel control signal including at least a component corresponding to a translational thrust command in a port direction, and that is configured to provide a set of actuator control signals coupled to and control the first and second reversing buckets. The processor is configured to provide the set of actuator control signals so as to maintain the first reversing bucket substantially in a first discrete position and the second reversing bucket substantially in a second discrete position as long as the first vessel control signal includes a component corresponding to a translational thrust command in the port direction.

Abstract: A commonly actuated trim and reverse system for a jet propulsion watercraft is provided. The system includes a movable actuator connected to a movement transfer mechanism. The movement transfer mechanism is operable to adjust both the trim angle of the steering nozzle of the watercraft and the orientation of the reverse gate, as a function of the movement of the actuator. Control electronics evaluate the target steering for the trim angle and gate orientation and control the movement of the actuator accordingly.

Abstract: A watercraft has a jet pump and a venturi. A variable trim system (VTS) support and a reverse gate are rotationally mounted relative to the venturi. A steering nozzle is rotationally mounted to the VTS support. A rotary actuator has an output portion operatively connected to at least one of the VTS support and the reverse gate. Rotation of the output portion between a first angle and a second angle causes a rotation of the VTS support while the reverse gate remains in a stowed position relative to the steering nozzle. Rotation of the output portion between the second angle and a third angle causes a rotation of the reverse gate between the stowed position and a second position while the VTS support remains in a fixed position. A jet propulsion system and a method of operating a jet propulsion system are also disclosed.

Abstract: Illustrative marine propulsion systems are disclosed. In a non-limiting, illustrative embodiment, a marine propulsion system includes a pump housing that is configured to be disposed below a waterline of a marine vessel and a centrifugal pump assembly that is disposed in the pump housing. The centrifugal pump assembly includes an inlet pump stage configured to receive inlet water and to discharge impulse water. The centrifugal pump assembly also includes an outlet pump stage that includes an impulse turbine wheel configured to rotate about an axis responsive to the impulse water and an outlet pump stage impeller integral with the impulse turbine wheel. The outlet pump stage impeller is configured to rotate about the axis.

Abstract: An electronically assisted reverse gate system for a jet propulsion watercraft is provided. Control electronics are in communication with the operator interface of the watercraft to obtain commands from the operator, such as a selection between a forward, reverse or neutral mode, a braking command or a slow mode. The control electronics evaluates the target setting for these commands. This evaluation is made taking into consideration the operating conditions of the watercraft. Control signals are sent to an appropriate actuating device to adjust the gate orientation accordingly.

Abstract: A marine jet propulsion system has a jet pump, a venturi connected to the jet pump, a first steering nozzle rotationally mounted relative to the venturi about a first steering axis, and a second steering nozzle rotationally mounted relative to the first steering nozzle about a second steering axis. The second steering axis is disposed rearwardly of the first steering axis. Rotation of the first steering nozzle relative to the venturi about the first steering axis in a steering direction causes the second steering axis to rotate about the first steering axis in the steering direction and the second steering nozzle to rotate relative to the first steering nozzle about the second steering axis in the steering direction. A watercraft having the jet propulsion system and a nozzle assembly for a marine jet propulsion system are also disclosed.

Abstract: A marine jet propulsion system has a jet pump, a venturi connected to the jet pump, and a steering nozzle rotationally mounted relative to the venturi about a first axis. The steering nozzle has a central longitudinal axis. The first axis intersects the central longitudinal axis. A first link has a first end rotationally mounted relative to the venturi about a second axis. The first link has a second end disposed generally rearwardly from the first end of the first link. A second link has a first end rotationally mounted to the first link about a third axis and a second end rotationally mounted to the steering nozzle about a fourth axis. The third axis intersects the second end of the first link. A steering arm is connected to the first link. The axes are generally parallel to each other. A watercraft having the jet propulsion system is also disclosed.

Abstract: A method for controlling a marine vessel having first and second steering nozzles and first and second trim deflectors comprises generating at least a first set of actuator control signals and a second set of actuator control signals. The first set of actuator control signals is coupled to and controls the first and second steering nozzles, and the second set of actuator control signals is coupled to and controls the first and second trim deflectors. The acts of generating and coupling the first set of actuator control signals and the second set of actuator control signals result in inducing any of a net yawing force, a net rolling force, and a net trimming force to the marine vessel without inducing any other substantial forces to the marine vessel by controlling the first and second steering nozzles and the first and second trim deflectors. Also disclosed is a system for controlling a marine vessel.

Abstract: The invention concerns a propulsion unit for a multihull such as a catamaran, comprising at least one turbine, seawater suction means and seawater backflow means. The invention is characterized in that said device comprises a seawater turbine directly driven by a motor inside each of the hulls (1), the seawater suction means being positioned at the front, outside each hull (1) in an overpressure zone generated by the bow wave and the seawater backflow means being positioned inside each hull (11), on the rear of the boat pitch pivot pin, said backflow means having an outlet (5) capable of being pivoted and emerging inside the channel defined between two hulls (1).

Abstract: The mechanism of the present invention maneuvers a vehicle by deflecting the flow from a propulsor of the vehicle. The mechanism has an elastomeric nozzle that encases the flow and is deflected via an articulation device mountable inside the vehicle. The nozzle is shaped and supported by spiral-wound composite to maintain a circular cross-section through a range of motion. An end of the nozzle is attached to the shroud of the propulsor and another end is supported by a ring with support struts radiating from a hub. The hub is supported by a shaft attached to a gimbal. The gimbal is constrained in movement by an outer race and an anti-rotation stud in a radial slot in a ball of the gimbal. A linkage as part of an articulation device controls rotation of the gimbal to direct movement of the shaft and enclosed nozzle thereby deflecting flow of the propulsor.

Abstract: A commonly actuated trim and reverse system for a jet propulsion watercraft is provided. The system includes a movable actuator connected to a movement transfer mechanism. The movement transfer mechanism is operable to adjust both the trim angle of the steering nozzle of the watercraft and the orientation of the reverse gate, as a function of the movement of the actuator. Control electronics evaluate the target steering for the trim angle and gate orientation and control the movement of the actuator accordingly.

Abstract: A trim adjusting device for a surface boat is provided that includes a nozzle for projecting jet water rearward arranged rearwardly of a jet propeller arranged in a boat body; a nozzle drive mechanism connected to the nozzle for operating the nozzle upward or downward; and an operating means arranged on a handle being connected to the nozzle drive mechanism. The nozzle drive mechanism includes a lever member connected to a trim operation lever of the operating means, a cam member provided with an engaging portion that engages the lever member arranged so as to be capable of rotating freely, a reverse rotation preventing claw member that engages the engaging portion, a link member that comes into abutment with the cam member at one end thereof, and the nozzle connected to the other end of the link member.

Abstract: Personal watercraft systems and watercraft power systems are described. The personal watercraft power systems include a housing for supporting a water jet pump and engine system. The housing is constructed to support the power system and removably engage a watercraft. An engine and a centrifugal pump are enclosed in the housing and operatively connected by an endless drive, such as a belt. A crankshaft of the engine is generally aligned and offset for a pump shaft of the centrifugal pump. An impeller is connected to the pump shaft and is constructed in rotate in a plane generally aligned, and preferably offset from, a plane of a water surface. The orientation of the engine and the centrifugal pump provides a watercraft power system that has a reduced profile and is particularly applicable for watercraft constructed to support an operator in a prone position.

Abstract: A water jet propeller for preventing an impeller from being exposed when the water jet propeller is disassembled. The water jet propeller includes a stator disposed at a rear-end portion of an impeller housing, and an impeller is disposed inside the impeller housing. The water jet propeller expels a water jet by rotating the impeller. The impeller of the water jet propeller is rotatably mounted to the stator, being disposed inside the impeller housing. The impeller housing, the stator, and a nozzle are connected integrally with each other using a connection bolt. The impeller housing and the stator are connected integrally with each other using a lock bolt.

Abstract: A system for controlling a marine vessel having at least first and second steering nozzles and corresponding first and second reversing buckets is disclosed. The system comprises a processor configured to receive a first vessel control signal and to provide a first set and a second set of actuator control signals. The first set of actuator control signals are to be coupled to and control the first and second steering nozzles and the second set of actuator control signals are to be coupled to and control the first and second reversing buckets. The processor is configured to provide the second set of actuator control signals so that the first reversing bucket and the second reversing bucket are each positioned in one of two discrete positions, in response to receipt of a translational thrust command having least one component in an athwart ship direction.

Abstract: A method for controlling a marine vessel having a first steering nozzle, a reversing deflector and at least one of a bow thruster and a second steering nozzle is disclosed. The method comprises the acts of inducing a net translational force to the marine vessel, corresponding to a first vessel control signal comprising only a translational thrust command and a zero rotational thrust command, so that substantially no net rotational force is induced to the marine vessel, and inducing a net force to the marine vessel, substantially in a direction of a combination of the translational thrust command and the rotational thrust command for all combinations of the rotational and translational thrust commands.

Abstract: A jet propulsion unit for a small watercraft includes a reverse thrust arrangement. The reverse thrust arrangement includes a water diverter bucket assembly moveable between an open position and a closed position with respect to a steering nozzle of the jet propulsion unit. An idle speed of the watercraft's engine can be manually and/or automatically adjusted between a low engine idle speed and a high engine idle speed. The lower engine idle speed allows comfortable shifting maneuvers. The higher engine idle speed provides for tighter turning when the throttle is released. The engine cannot be started unless the reverse trust arrangement is in a partially open position.

Abstract: A trim operating wire is disclosed wherein the length of the pull wire connecting between the push-pull converter and the trim operating lever can be made short, and the push wire can be made long. As a result, even where the pull wire, which is thin and highly flexible, is disposed in the state of being bent at several portions thereof, the sliding resistance of an inner wire of the pull wire is small, and operability is enhanced.

Abstract: A braking system for a personal watercraft includes at least one brake plate for mounting to the transom of a personal watercraft such that the jet nozzle of the watercraft is directionally adjustable independently of the braking system. The brake plate is alternatable between a nonbraking condition wherein the plate is retracted against the transom and is held completely above a lower edge of the transom, and a braking condition where the brake plate extends beyond the lower edge of the transom. A hand-controlled actuator assembly selectively alternates the brake plate between the braking and nonbraking conditions.

Abstract: A personal watercraft has a structure in which a steering nozzle is mounted onto a jet nozzle so as to be swingable vertically and in the left-right directions, upper and lower support shafts for mounting the steering nozzle include upper and lower bolts, the upper and lower bolts set such that the heads thereof are directed toward the jet nozzle, and the lengths of the upper and lower bolts are set such that the upper and lower bolts can be fastened to the steering nozzle when the heads of the upper and lower bolts come into contact with the jet nozzle.

Abstract: The present invention relates to a steering arrangement for ships with a water jet unit, comprising a steering device that is pivotable about an essentially vertical shaft having a first center line, at least one hydraulic cylinder articulately connected at a first end of the hydraulic cylinder to the attachment flange of the water jet unit, a turning device connected to the shaft for attachment to a second end of the hydraulic cylinder at a distance from the shaft, a reversing device for pivoting the steering device, the reversing device being arranged about an essentially horizontal shaft, an additional hydraulic cylinder arranged to act on the reversing device, the additional hydraulic cylinder following the movement of the steering device, characterized in that all the hydraulic cylinders are arranged within a sheltered space located above the extension of the vertical shaft.

Abstract: A personal watercraft having an engine, a water jet propeller on the rear side of the engine, a jet nozzle for ejecting jet water, and a steering nozzle swingable in the left-right direction. The axis of the water jet propeller is set with a rearwardly downward gradient at an angle ?1, and the bottom surface of a ride plate is set with a rearwardly upward gradient at an angle ?2.

Abstract: A trim operating lever device is disclosed which can downwardly or vertically swing a nozzle capable of adjusting the jet direction of jet water. When the trim operating lever is gripped with a finger of the hand which is gripping the steering handle, a lever of the lever lock means can be substantially simultaneously operated with the finger, to effect locking. Therefore, the number of operations by the left hand necessary for swinging the nozzle is reduced. Also, because the trim operating lever makes it possible to enlarge the operating force, the nozzle can be swung quickly.

Abstract: A dual axis joystick control system is used intuitively for maneuvring a waterborne vessel having two or more waterjets with steering deflectors (13) and reverse ducts (14) mounted independently of the steering deflectors. The joystick (21) is operated to actuate the reverse ducts of the port and starboard waterjets for either common or differential deflections of thrust, and to actuate the steering deflectors of the port and starboard waterjets for common deflections of thrust.

Abstract: A system and method for constructing a reverse gate for a watercraft is disclosed. The reverse gate is independently rotatable relative to a watercraft and a steering nozzle and includes at least two curved surfaces. The curved surfaces are attached to one another to form an apex that is offset from a midpoint of the reverse gate and the reverse gate is attached to the watercraft so that the apex is also offset from a center axis of a steering nozzle oriented relative thereto. Water discharged from the steering nozzle can be diverged at the apex of the reverse gate to provide lateral and reverse thrust to the watercraft. The reverse gate includes an additional curved section contained within one of the at least two curved sections to provide improved lateral thrust to the watercraft.

Abstract: An apparatus and method are disclosed which allow a stream to be divided so that a portion continues to provide forward or reverse thrust while a portion is diverted to provide lateral thrust. The apparatus has a frame and a side diverter connected thereto. The side diverter is movable into and out of the path of a water stream from a jet propulsion unit to divert at least a portion of the water stream to provide lateral thrust. The apparatus preferably has two side diverters that may or may not be independently operable. The apparatus also preferably has one or more reverse diverters connected to the frame. The frame is preferably pivoted about two axes to move the side diverters into and out of the path of the water stream, and the reverse diverter preferably pivots about an axis that is perpendicular to these axes.

Abstract: A watercraft of the jet propulsion type comprising a steering mechanism, a throttle control mechanism, a thrust mechanism, a throttle regulator and a controlled thrust steering system. The steering mechanism has a straight-ahead position. The steering mechanism is able to rotate in a clockwise direction from the straight-ahead position to a clockwise position and in a counter-clockwise direction from the straight-ahead position to a counter-clockwise position. The throttle control mechanism is biased toward an idle position. The thrust mechanism provides jet propulsion thrust for the watercraft. The throttle regulator regulates thrust provided by the thrust mechanism. The controlled thrust steering system causes the throttle regulator to increase thrust upon the steering mechanism rotating from the straight-ahead position to the clockwise position or the counter-clockwise position.

Abstract: To provide a jet propulsion boat which can be efficiently propelled by disposing a steering nozzle closer to the bottom of the boat. A jet propulsion boat includes a jet propulsion apparatus driven by an engine at the stern. A jet nozzle for jetting water is provided at the rear portion of the jet propulsion apparatus. A steering nozzle is swingably supported by the jet nozzle so as to adjust the direction of a stream of water jetted from the jet nozzle. In the jet propulsion boat, an outlet side of the jet nozzle is covered with an inlet side of the steering nozzle and the vertical diameter D2 of the inlet of the steering nozzle is set to be smaller than the transverse diameter D1 of the inlet.