The present invention deals with a silent jet propulsion system installed inside the hull of a military submarine with a method for propelling a military submarine and the like to eliminate the conventional propulsion systems noise and to steer the military submarine in silent, fast, efficient and highly maneuverable fashion.

In the present invention, there is no propeller installed outside the military submarine hull. The silent jet propulsion system of the present invention will generate a laminated turbulent free water jet flow thrust which will propel the military submarine in the desired speed and the desired direction.

In the present invention, the desired speed and the desired direction of movement of the military submarine is accomplished by controlling the amount and the direction of the generated water jet flow thrust of the silent jet propulsion system installed inside the military submarine hull.

The present invention deals with a silent jet propulsion system installed inside the hull of a military submarine with a method for propelling a military submarine and the like to eliminate the conventional propulsion systems noise and to steer the military submarine in silent, fast, efficient and highly maneuverable fashion.

In the present invention, there is no propeller installed outside the military submarine hull. The silent jet propulsion system of the present invention will generate a laminated turbulent free water jet flow thrust which will propel the military submarine in the desired speed and the desired direction.

In the present invention, the desired speed and the desired direction of movement of the military submarine is accomplished by controlling the amount and the direction of the generated water jet flow thrust of the silent jet propulsion system installed inside the military submarine hull.

A propulsion assembly utilizes at least one fluid propulsion chamber operationally attached or mounted to a vessel. Each fluid propulsion chamber generally comprises an outer housing and an inner sleeve; the outer housing is slidably disposed relative to the inner sleeve. Each inner sleeve further includes at least one water intake vent or aperture, and at least one outlet nozzle or jet. Pedal assemblies are moveably mounted within elongated slots or apertures extending through the vessel. A linkage assembly operationally connects the pedals to the at least one fluid propulsion chamber. Force imparted on said pedals (such as by the legs/feet of a user) is transferred to the fluid propulsion chambers by said linkage assembly to generate positive thrust to propel the vessel.

A propulsion assembly utilizes at least one fluid propulsion chamber operationally attached or mounted to a vessel. Each fluid propulsion chamber generally comprises an outer housing and an inner sleeve; the outer housing is slidably disposed relative to the inner sleeve. Each inner sleeve further includes at least one water intake vent or aperture, and at least one outlet nozzle or jet. Pedal assemblies are moveably mounted within elongated slots or apertures extending through the vessel. A linkage assembly operationally connects the pedals to the at least one fluid propulsion chamber. Force imparted on said pedals (such as by the legs/feet of a user) is transferred to the fluid propulsion chambers by said linkage assembly to generate positive thrust to propel the vessel.

There is provided a hull assembly for reducing water resistance on a ship hull and improving the maneuverability on said ship. The hull assembly is mountable on a pre-existing ship hull having a bow, and a stern. The hull assembly comprises a propeller chamber for enclosing at least one propeller positioned proximate the stern of the ship hull, and a plurality of ducts attachable to an outer surface of the ship hull. The ducts extend in a longitudinal direction from a front part of the bow to the propeller chamber. The ducts have a plurality of bow openings along the bow for the water to flow directly toward the rear part of the stern, each of the ducts comprising at least one stern opening near the propeller chamber. The propeller chamber comprises two opposed chamber sides; at least one chamber opening on each of the two opposed chamber sides; and a rear opening for each of the at least one propeller.

A jet propulsion device includes an impeller housing, an impeller, a sleeve, a first ring-shaped elastic body, and a second ring-shaped elastic body. The first ring-shaped elastic body is disposed between the impeller housing and the sleeve, and is located between a first end and a middle of the sleeve in an axial direction of the sleeve. The second ring-shaped elastic body is disposed between the impeller housing and the sleeve, and is located between a second end and the middle of the sleeve in the axial direction of the sleeve.

A jet propulsion device includes an impeller housing, an impeller, a sleeve, a first ring-shaped elastic body, and a second ring-shaped elastic body. The first ring-shaped elastic body is disposed between the impeller housing and the sleeve, and is located between a first end and a middle of the sleeve in an axial direction of the sleeve. The second ring-shaped elastic body is disposed between the impeller housing and the sleeve, and is located between a second end and the middle of the sleeve in the axial direction of the sleeve.

A hydrofoil craft includes a deck, a hydrofoil disposed below the deck, a thruster that generates a thrust, and a thrust operator. The deck includes a chest placing portion on which a chest of a vessel operator is placed and a lower-limb placing portion that is disposed at a more rearward position than the chest placing portion and on which a lower limb of the vessel operator is placed, and the deck is arranged such that the vessel operator is able to ride on the deck in a prone position. The thrust operator is operated by the vessel operator to adjust the thrust of the thruster.

A hydrofoil craft includes a deck, a hydrofoil disposed below the deck, a thruster that generates a thrust, and a thrust operator. The deck includes a chest placing portion on which a chest of a vessel operator is placed and a lower-limb placing portion that is disposed at a more rearward position than the chest placing portion and on which a lower limb of the vessel operator is placed, and the deck is arranged such that the vessel operator is able to ride on the deck in a prone position. The thrust operator is operated by the vessel operator to adjust the thrust of the thruster.

A small marine vessel includes a vessel body, a propulsion device, a propulsion device housing provided in a rear portion of the vessel body and that houses the propulsion device, a first cover that substantially covers and seals the propulsion device housing, and a second cover disposed above the first cover and that covers the first cover and an opening of the propulsion device housing.