Abstract: The device of the present invention comprises a footwear member such as a sandal, attached to a swimmer's foot by strap or thong means, and a forwardly projecting fin shaped frame member, fixed to the sandal and including a plurality of longitudinally extending vanes, pivotally attached between the opposed end wall portions of the frame. When the swimmer moves the device inwardly toward his or her body, the vanes open in response to the reactive forces of the water, permitting the water to pass between the vanes; when the device is moved away from the body, the reactive forces of the water close the vanes relative to each other, creating a condition whereby the swimmer is propelled forwardly through the water.

Abstract: Apparatus to automatically inflate a life raft secured to the side of a boat hull by releasing a pressurized gas from a cylinder when the boat capsizes. The gas release mechanism for the cylinder includes a spring urged valve and a spring loaded plunger arranged to open said valve upon release. The plunger is held in an extended position by a lever arm pivotal about a pin and held by an extending arm connected to weights such that when the boat is overturned the weights pivot away from the lever arm due to the force of gravity, releasing the plunger, thereby releasing gas from the cylinder to inflate the life raft.

Abstract: A buoyant shock absorbing device for an aquatic tow rope having interchangeable component parts and a two piece housing having draining and venting apertures therein facilitating inspection of the component parts and serving as a gripping aid to assemble or dismantle the housing.

Abstract: An anchor davit to facilitate handling an anchor cable and to stow the anchor in a safe, secure position when it is raised out of the water. The davit provides a cable centering, direction changing roller, rotatably supported on a mounting bracket to guide the cable over the side of a boat and to cradle and cushion the raised anchor. A retaining loop, pivotally supported on the bracket, is coaxial with the roller and cooperates therewith to hold the cable on the roller and brings about a suitable stowing position of the anchor.

Abstract: An inflatable bouyancy aid comprises an elongate, straight inflatable member, and a securing device attached to and extending from the inflatable member and adapted to encircle the trunk part of the body of a wearer. An actuating device is associated with a gas producing device located in or adjacent the inflatable member such that on operation of the actuating device an amount of gas flows into the inflatable member so as to inflate it and provide buoyancy for the wearer. The securing device extends from two positions spaced apart and removed from each end of the inflatable member to leave two end portions of the inflatable member, when inflated, extending in substantial tangential fashion from the body of the wearer.

Abstract: A collapsible raft includes opposed hinged rigid hull and deck members joined by a flexible watertight skirt and surrounded by a peripheral inflatable tube. The hinge plates interconnecting the hull and deck may be selectively locked in an open condition. In the preferred form, the hull and deck members each include a water sealable hatch and appropriately valved ventilator tubes that render the raft invertible and serve to protect the occupant(s) from drowning and exposure. A second form of the invention is embodied in a pleasure craft wherein the deck is open and includes a seating arrangement and provision for mounting an outboard motor.

Abstract: An improved mooring buoy is provided having means for maintaining the shackle at the upper end of its hawser above water level when the buoy is at rest in the water. The buoy is provided with a floating body having a generally vertical passage extending therethrough. The lower end of the hawser is shackled to a weighted line, such as a chain, which is connected to a dead weight. Both the weighted line and the hawser are slidable freely through the passage relative to the floating body of the buoy. Means are provided for limiting the downward sliding movement of the hawser relative of the floating body, to thereby maintain the upper end of the hawser above the water level. The buoy also may be provided with a skirt extending below the floating body to a depth sufficient to terminate below the usual level of the ship's propeller, to prevent the propeller from becoming entangled in the submerged weighted line.

Abstract: The invention relates to a gas-driven pulsating water jet propulsive duct drive for watercraft with a propulsive duct which has at the front end an inlet aperture for water with a closure member closing and opening periodically by means of a drive device, is open at the rear end for ejection of water and comprises at the front end a power gas outlet behind the inlet aperture. With propulsive duct drives of this kind the forward inlet aperture of the water-filled propulsive duct is periodically closed, the power gas outlet opened, in order to feed power gas under pressure into the propulsive duct and to expel the fluid filling of the propulsive duct rearwards, the power gas outlet is closed and the forward inlet aperture opened again for a fresh fluid filling.

Abstract: In a ship's roll damping tank, means are provided that are operative to extract substantial wave velocity energy from the liquid in the tank. Perforated pipes are laid in spaced parallel relationship across the bottom of the tank, i.e. in the fore and aft direction of the ship, to create, by injection from the pipes into the tank liquid, upflows of fluid that interfere with the normal orbital movement of the tank liquid wave particles.Wave velocity energy can likewise be extracted by means of an apertured false bottom, upward protuberances on the tank floor, and perforated or unperforated horizontal end baffles.

Abstract: The hydraulic system for raising and lowering a heavy keel comprises a cylinder, a piston movable in the cylinder and connected to the keel, and an accumulator for supplying hydraulic fluid at a positive pressure below that necessary to raise the keel against the piston in a direction for raising the keel. A hand pump is provided for supplying hydraulic fluid at a pressure great enough to overcome the weight of the keel. A valve allows the hydraulic fluid to flow either to or from the cylinder. An enlarged flow line communicates the accumulator with the cylinder so that if an external force should cause the keel to raise suddenly, hydraulic fluid would flow rapidly beneath the piston. A gas is provided on the other end of the piston for providing a cushioning effect and restricting the speed at which the keel can be raised. A restricted flow valve is provided in the system for regulating the speed at which the keel can be lowered.

Abstract: A shallow water moored buoy having an anchor retaining mechanism on a bot deck which automatically releases an anchor when the buoy strikes water. The buoy is filled with floatation material which encloses electronic and battery packages and has an antenna mounted on an upper deck and hydrophone sensors attached to a deployable anchor cable which is secured to the center of the bottom deck.

Abstract: An accessory for attachment to the transom of a power boat for providing a relatively high easy release tow rope attachment point above the general level of the boat stern is disclosed comprising a plurality of telescopingly engaged tubular members having at least a pair of elbow portions in L-shaped tubular members with tow rope attachment device such as a ring and stud located on a tubular member between the elbow portion and having means associated with adjacent pairs of telescoping tubular members for fastening those pairs together. Two of the fasteners also function to attach the accessory to the boat transom and the telescoping overlaps may be provided with a plurality of alignable apertures thus allowing the height and width of the accessory to be adjustably determined for a particular installation.

Abstract: An apparatus for pivotally mounting an outboard fishing motor, such as a shaft-mounted submersible electric motor, on the bow of a fishing boat or the like for pivotal movement between an operative position wherein the motor is held in the water and a non-operative raised position. The apparatus comprises an elongated mounting frame, a slide block carried by the mounting frame, and a bracket pivotally carried by the slide block for supporting the shaft of the motor. A power control system is provided which includes a reversible electric motor and cable arrangement for selectively translating the slide block in either direction, and a pivoting and lifting arrangement is included which serves to lift the outboard motor into its raised position overlying the mounting frame.

Abstract: A device for reducing the roughness of ride of a Surface Effect Ship and producing power for use in the craft's auxiliaries. Cushion air is vented through a duct which has a generator in it; the power-absorbing capability of the generator is variable. Varying the amount of power absorbed by the generator varies the amount of air that is vented through the duct, thereby controlling the pressure in the air cushion.

Abstract: A bottom-dump vessel, whose longitudinal hull sections can be pivoted apart by jack means to provide an open bottom for discharge of cargo, has the adjoining edges of the keels of the hull sections interconnected by articulated rods which in substantial side-by-side position loch the hull sections in the closed position and in substantial end-to end position limit the angle of opening of the hull sections. The locking rods have means for positively driving them, thereby allowing for rapidly opening the vessel and transmitting appropriate braking forces to cope with mass forces. The arrangement makes for moderation in the size of jacks and other facilities required.

Abstract: A mooring buoy for tanker ships is provided with vertical flow channels through which fluids may be passed from an undersea pipeline to a buoy-to-ship hose. Inlets to the flow channels are provided at their lower ends and outlets at their upper ends. To enable a ship moored to the buoy to swing around the buoy during loading, one or more flow channels are provided around a central flow channel, the outlets from each of these flow channels being rotatable about the axis of the central flow channel.

Abstract: A device for use with a conventional loop-provided boat line to effect docking or mooring of boats comprising a pair of rigid arms for detachable engagement upon opposed portions of the strands of the loop near the base thereof; there being a pivotal connection between each of the rigid arms adjacent their rearward or loop remote ends for swingable movement of the same away from and toward each other, or into open or closed condition, respectively. The rearward ends of these arms are formed to provide cooperating jaws for clamping relationship upon an interposed implement as the arms are moved away from each other for loop opening through a pulling force upon the line.

Abstract: The swimmer's aid is a generally S-shaped board having means on the upper surface thereof for engagement with the hands of a swimmer. The swimmer holds the board in front of him with his arms extended and propels himself by means of kicking his legs. The rearward end of the board is downturned to act as a drag. The forward end of the board is upturned to minimize any tendency of the board to dive into the water during use. The swimmer's aid is a practice device intended to assist in improving a swimmer's ability.

Abstract: A submersible oil-storage tank is constructed from a foundation plate which has a flat lower face and a concave upper face and contains a series of hollow cells, a cupola mounted on the foundation plate to form a spheroidal chamber, and extensible-retractable tie members connecting the cupola with the foundation plate. An expansible separating wall extends across the chamber and divides it into a lower sub-chamber and an upper sub-chamber. Each sub-chamber is provided with a valved duct so that water may be permitted to flow into or out of the lower sub-chamber and oil may be permitted to flow into or out of the upper sub-chamber.

Abstract: A system for utilizing a power assit for rotating a boat motor about a vertical axis near the stern of the boat. The power assist is provided by a small rudder mounted along the center line of the motor and positioned in a vertical plane through the axis of the propeller and aft of the propeller in the slip stream. Means are provided to operate the small rudder by the apparatus that controls the rotation of the motor, the rotation of the rudder being effected prior to applying torque to rotate the motor assembly. In operating the turning control for rotating the motor assembly, there is a slack condition whereby the first movement of the control rotates the small rudder into a position whereby the moving slip stream from the propeller exerts a torque tending to rotate the motor assembly in the desired direction. If the torque is insufficient to rotate the motor, movement of the control in a continuing direction applies a torque to directly rotate the motor assembly.