A handheld underwater aircraft includes a battery compartment (12) and propellers. There are at least two propellers, which are symmetrically distributed on both sides of the battery compartment (12), and are connected to the battery compartment (12). A special design with axes of the propellers being unparallel with an axis of the battery compartment (12) is adopted, and unparallel included angles make component forces generated by the various propellers in a direction of motion of a non-underwater aircraft offset each other, and enable the underwater aircraft to maintain balanced and forward-forward motion. The design with the axes of the propellers being unparallel with the axis of the battery compartment (12) leads to a little power loss, but avoids a larger power loss caused by the impact of water on the human body, thereby comprehensively improving the thrust of the underwater aircraft in use.

A handheld underwater aircraft includes a battery compartment (12) and propellers. There are at least two propellers, which are symmetrically distributed on both sides of the battery compartment (12), and are connected to the battery compartment (12). A special design with axes of the propellers being unparallel with an axis of the battery compartment (12) is adopted, and unparallel included angles make component forces generated by the various propellers in a direction of motion of a non-underwater aircraft offset each other, and enable the underwater aircraft to maintain balanced and forward-forward motion. The design with the axes of the propellers being unparallel with the axis of the battery compartment (12) leads to a little power loss, but avoids a larger power loss caused by the impact of water on the human body, thereby comprehensively improving the thrust of the underwater aircraft in use.

An electric marine propulsion system including steering and vertical position control is provided. The electric drive assembly includes a main drive motor transmitting torque through a shaft to a propeller. The electric drive assembly integrates a dual rudder system positioned ahead of the main drive propeller. The rudder assemblies integrate electric stern thrusters for low-speed maneuvering. The steering and vertical position adjustments for the drive assembly are electrically operated. The electric drive assembly is installed entirely outside the hull of the watercraft.

An electric marine propulsion system including steering and vertical position control is provided. The electric drive assembly includes a main drive motor transmitting torque through a shaft to a propeller. The electric drive assembly integrates a dual rudder system positioned ahead of the main drive propeller. The rudder assemblies integrate electric stern thrusters for low-speed maneuvering. The steering and vertical position adjustments for the drive assembly are electrically operated. The electric drive assembly is installed entirely outside the hull of the watercraft.

A survival craft for maritime evacuation of passengers and crew members from a vessel or an offshore facility is disclosed. The survival craft has a hull, predominantly made of non-rigid inflatable tubes and one or more shells, the hull has a length, a width and a centerline, a bow and a stern. The survival craft further comprises a first pair of engine-powered propulsion means arranged at the stern on opposite sides of the centerline, and a second pair of engine-powered propulsion means arranged at the bow on opposite sides of the centerline, each engine-powered propulsion means has a propeller or a water jet, wherein a horizontal angle of each propeller or water jet of each engine-powered propulsion means can be independently set in relation to the centerline.

A survival craft for maritime evacuation of passengers and crew members from a vessel or an offshore facility is disclosed. The survival craft has a hull, predominantly made of non-rigid inflatable tubes and one or more shells, the hull has a length, a width and a centerline, a bow and a stern. The survival craft further comprises a first pair of engine-powered propulsion means arranged at the stern on opposite sides of the centerline, and a second pair of engine-powered propulsion means arranged at the bow on opposite sides of the centerline, each engine-powered propulsion means has a propeller or a water jet, wherein a horizontal angle of each propeller or water jet of each engine-powered propulsion means can be independently set in relation to the centerline.

The present invention relates to a hull in particular for a container ship, a bulk carrier and a tanker. The hull includes an elevation of an outer contour of the hull with respect to an upwards directed vertical direction of the hull in the region of a first body plan and a second body plan in relation to a surface section immediately adjoining to the elevation. Therein, the elevation is arranged in a region between a middle and a stern of the hull.

A watercraft is provided having at least one floating body which is designed to be elastically flexible, at least in part, and to carry at least one person above a waterline, and is, in particular, inflatable and/or made from a foam material at least in part. The watercraft includes a drive device which comprises at least one first drive unit designed to generate a first water flow below the waterline. The first drive unit is designed in such a way that the alignment of the first water flow relative to the floating body can be changed. The drive device comprises at least one second drive unit designed to generate a second water flow below the waterline, and is designed, in particular, in such a way that the alignment of the second water flow relative to the floating body can be changed.

A watercraft is provided having at least one floating body which is designed to be elastically flexible, at least in part, and to carry at least one person above a waterline, and is, in particular, inflatable and/or made from a foam material at least in part. The watercraft includes a drive device which comprises at least one first drive unit designed to generate a first water flow below the waterline. The first drive unit is designed in such a way that the alignment of the first water flow relative to the floating body can be changed. The drive device comprises at least one second drive unit designed to generate a second water flow below the waterline, and is designed, in particular, in such a way that the alignment of the second water flow relative to the floating body can be changed.

A method of de-spinning a rotor of a propulsion system includes providing one or more spinning rotors rotatably mounted on a frame with a bearing having a bearing outer race, bearing balls, and bearing inner race; providing a force mechanism coupled with the one or more spinning rotors for applying a load to the one or more spinning rotors; and loading an outer portion of the outer bearing race, bearing ball, and inner bearing race of the bearing, a load on the outer portion of the bearing race, bearing ball, and inner bearing race of the bearing corresponding to a force applied to the one or more spinning rotors by the drive mechanism. The one or more spinning rotors de-spin at a rate corresponding to the load on the bearing balls.