A linking drive system comprises a first drive shaft of the first drivetrain connected between a first prime mover and a first propulsor. The linking drive system comprises a second drive shaft of the second drivetrain connected between a second prime mover and a second propulsor. The linking drive system further comprises a linking drive clutch, which comprises at least a first clutch part and a second clutch part. The first clutch part and the second clutch part are engageable with each other and can transmit rotation therebetween. At least one flexible drive link is coupled between the linking drive clutch and the first and/or second drive shafts. Rotation from one of the first and second drive shafts is transferred to the other of the first and second drive shafts when the linking drive clutch is engaged thereby linking the first and second drivetrains.

A watercraft comprising a compressed air propulsion system is shown and described. The watercraft includes at least one propeller operatively connected to an air motor. Storage tanks supply compressed air having a pressure of at least 2000 psi to a pressure regulator that reduces the pressure and supplies air to an air control valve. User controls adjust the air control valve to adjust the flow rate of air to the air motor which in turn adjusts the direction and/or speed of rotation of the propeller. An on-board air compressor energized by a plurality of lithium iron phosphate batteries provides air to the air storage tanks when the pressure falls below a specified value. In certain examples, the electric and air propulsion system is used to replace a fossil fuel engine in an existing watercraft and can remain at sea longer than the existing watercraft.

A waterfowl decoy deployment system includes a thrust device and a hub coupled to the thrust device. The waterfowl decoy deployment system also includes a plurality of arms coupled to the hub such that the plurality of arms extend radially outward from the hub. The thrust device is configured to rotate about an axis to induce a substantially circular motion to the hub and the plurality of arms.

In a marine vessel, a propulsion system comprises at least one propeller having a direction of rotation about a drive shaft and a bulbus protrusion extending from the hull associated with each of the at least one propeller, each protrusion extending from the hull of the vessel, each protrusion receiving and rotatably supporting the at least one propeller. Each protrusion extends between leading and trailing ends and has a substantially circular cross section along a length between the leading and trailing ends having and a leading portion extending from the leading end wherein the leading portion is angled away from the centerline of the hull.

A watercraft propulsion system includes a bow thruster at a bow of a hull to generate a lateral propulsive force, at least two propulsion devices on a stern of the hull each having a variable steering angle, and a controller configured or programmed to control the propulsive force of the bow thruster and control the propulsive forces and the steering angles of the two propulsion devices to perform an azimuth control to control an azimuth of the hull. The azimuth control includes a bow thruster mode in which the bow thruster is controlled, and a combinational mode in which the bow thruster is controlled and the two propulsion devices are driven forward and in reverse, respectively. The controller switches between the bow thruster mode and the combinational mode based on a predetermined switching condition during the azimuth control.

A watercraft propulsion system includes a bow thruster to generate a lateral propulsive force, a propulsion device on a stern of a hull and having a variable steering angle, and a controller configured or programmed to control the bow thruster and the propulsion device to perform a fixed point holding control to maintain a position and an azimuth of the hull. The fixed point holding control includes a translation mode in which the hull position is maintained by controlling the propulsive force of the propulsion device with the steering angle set to a translation mode steering angle and the hull azimuth is adjusted by controlling the propulsive force of the bow thruster, and a bow turning mode in which the hull azimuth is adjusted by controlling the propulsive forces of the bow thruster and the propulsion device with the steering angle set to a bow turning mode steering angle.

A watercraft propulsion system includes a bow thruster, at least two propulsion devices, a translation operator to command a hull translation movement, and a controller configured or programmed to, in a translation watercraft maneuvering mode, control the propulsion devices so that propulsive force action lines thereof cross each other in the hull, and to drive one of the propulsion devices forward and drive another of the propulsion device in reverse. In a standby state, the controller is configured or programmed to prevent the bow thruster and the propulsion devices from generating propulsive forces, and set the steering angles of the propulsion devices to translation standby steering angles. In response to the operation of the translation operator, the controller is configured or programmed to cause the bow thruster and the propulsion devices to start generating the propulsive forces, and change the steering angles of the propulsion devices to translation steering angles.

A watercraft propulsion system includes a bow thruster, at least two propulsion devices, a translation/bow turning operator to apply a translation command to translate a hull and a bow turning command to turn a bow of the hull, and a controller configured or programmed to drive the bow thruster, and drive one of the at least two propulsion devices forward and another of the at least two propulsion devices in reverse while controlling the steering angles of the at least two propulsion devices so that propulsive force action lines of the at least two propulsion devices cross each other in the hull in a translation watercraft maneuvering mode to translate the hull in response to an operation of the translation/bow turning operator. The controller includes a calibration mode in which calibration is performed for the translation watercraft maneuvering mode.

A vessel hull for an inboard-powered marine vessel includes a hull body having a hull bottom that includes a contoured pod mounting surface positioned longitudinally between a central keel and a stern of the hull body. The contoured pod mounting surface has a planar mounting face, for mounting a propulsor pod, and a transition face each positioned between peripheral edges of the pod mounting surface. The transition face slopes forwardly and downwardly from the planar mounting face to the central keel and follows a contour defining a sine wave pattern.

A vessel hull for an inboard-powered marine vessel includes a hull body having a hull bottom that includes a contoured pod mounting surface positioned longitudinally between a central keel and a stern of the hull body. The contoured pod mounting surface has a planar mounting face, for mounting a propulsor pod, and a transition face each positioned between peripheral edges of the pod mounting surface. The transition face slopes forwardly and downwardly from the planar mounting face to the central keel and follows a contour defining a sine wave pattern.