The object of the invention is an inflatable watercraft (1) (SUPstand up paddling) with an embedded drive and having a specially shaped recess in the center, preferably in the center of gravity of the watercraft (1), into which a housing (2, 2) of a drive assembly is inserted before the watercraft is filled with air. While the watercraft (1) is filled with air, the air pressure firmly fixes the housing (2, 2) of the drive assembly to a proper position. The housing (2, 2) accommodates the drive assembly that comprises a storage battery (4), an electric motor (5), a compressor (3) and an electronic circuit (8), wherein the drive assembly is provided with a flow-through channel (6), in which a drive screw (7) is arranged, and both the input and the output sides of the flow-through channel (6) are protected by grates.

A boat comprises a deck supported by one or more deck floats, and a paddle wheel cockpit comprising a seat proximal to a pedal-driven paddle wheel adapted to engage water and propel the boat; wherein the deck and the paddle wheel cockpit are joined by at least one cockpit hinge that allows the paddle wheel cockpit to fold over the deck, in some embodiments.

What is provided is a propeller guard apparatus that may be readily configured to a variety of different boat motors. Described embodiments of the propeller guard apparatus comprise a cylindrical housing configured to circumferentially enclose a propeller from all sides in order to protect humans, pets, and aquatic wildlife from being entangled or cut by the propeller. Described embodiments of the propeller guard apparatus also comprise a protective structure, such as a skid plate comprising of at least two pieces of metal attached from the cylindrical housing to an end of the outer casing to form a folded T-shaped configuration. This type of configuration serves to protect the propeller from damage caused by submerged objects and aquatic wildlife found in shallow water. Also, the folded T-shaped configuration may push vegetation, weeds, manatees, and other aquatic wildlife away from the path of the moving boat and its propeller.

A system for cutting marine grasses, weeds and other plant life to protect a propeller drive watercraft is disclosed. An adjustable, protective cutting edge to protect a propeller, drive shaft of a boat or other watercraft motor is further disclosed. An adjustable cutting device to mount upon base having openings or windows is further disclosed for optimizing the navigation of watercraft and reducing in-piloting maintenance of clearing plant matter from propeller driven motor assembly.

A marine propulsion system includes a water intake guide block with a flow guide passage, a propulsion device including a housing connected to the water intake guide block and a propeller mounted in the housing, a fixed nozzle connected to the housing of the propulsion device, a swinging nozzle connected to the fixed nozzle and biasable leftward and rightward relative to the fixed nozzle, and a contra type bossing pivotally connected to the fixed nozzle and biasable up and down relative to the fixed nozzle. When rotating the propeller, water is sucked into the flow guide passage and propelled by the propeller to eject backward through the fixed nozzle, and the swinging nozzle is biased leftward/rightward to control leftward/rightward turning of the boat, and the contra type bossing is biased upward/downward to control the pitch angle of the boat and forward/backward movement of the boat.

A grid (100) is for a tunnel thruster (200). The grid (100) includes a plurality of first radially extending bars (101) arranged at angular intervals from each other, and a plurality of first connecting bars (102). Each of the first connecting bars (102) are connected between adjacent first radially extending bars (101).

A marine propulsion system for shallow waters, swamps, savannahs and the like includes a rotating propeller shaft supporting a propeller. An anti-cavitation body defines a partial cylinder having a longitudinal axis adjacent to the propeller. The propeller generates a vacuum between the anti-cavitation body and a surface of a water body. First and second wings adjacent to edges of the anti-cavitation body are generally planar and operatively angled towards the bottom of a water body. The first and second wings are adjusted to run below the water body surface and seal the anti-cavitation body to maintain generated vacuum. A first thread is cut in a first helical direction at an end of the rotating propeller shaft adjacent the propeller, and slightly more distal therefrom a second thread is cut in a second helical direction opposed to the first thread helical direction. The second thread drives matter away from the bearing.

Disclosed are devices, methods and/or systems for use in protecting items and/or structures that are exposed to, submerged and/or partially submerged in aquatic environments from contamination and/or fouling due to the incursion and/or colonization by specific types and/or kinds of biologic organisms and/or plants, including the protection from micro- and/or macro-fouling for extended periods of time of exposure to aquatic environments.

The presently disclosed subject matter is directed to an adaptor that can be used to eliminate the gap present between the motor housing and the propeller in conventional trolling motors. Particularly, the disclosed adaptor comprises a first shell and a second shell that attach together and surround the base of the trolling motor propeller therebetween. As shown, the propeller blades extend from one or more apertures in the adaptor. The adaptor attaches to the trailing end of the motor housing and is maintained on the drive shaft through the use of one or more fasteners.

A portable propulsion system for a watercraft may include a shaft, a propeller, an outer casing, and a flexible strap. The shaft may have a prop end section, a drive end section, and a rotational axis extending from the prop end section to the drive end section. The propeller may be connected to the prop end section of the shaft. The drive end section may be configured for removable connection to a driver for rotation of the propeller via rotation of the shaft about the rotational axis to propel the watercraft. The outer casing may be disposed around the shaft. The flexible strap may have first and second end sections connected to the outer casing in respective first and second regions.