Abstract: An interdiction system to be placed upon the floor of the ocean includes a arget detection and classification system which is cooperatively connected to a hollow enclosure containing a predetermined volume at one atmosphere or less pressure. Upon target aquisition and classification, the detection and classification system actuates a mechanism to rupture the wall of the hollow enclosure. The resultant implosion caused by the ambient ocean pressure creates a high intensity shock wave in the vicinity of the system to damage the intruding vessel.

Abstract: A detector unit for investigation of fluid currents in conducting liquids, uch as sea water, for example, employs two similar metal electrodes in contact with the fluid, one exposed to the fluid current and the other protected therefrom.

Abstract: A device employing a permanent magnet is used to provide a sweep for magnetically activated marine mines.

Abstract: Disclosed is an improved underwater half-second pyrotechnic delay device ing an elongated tubular housing with a pair of holes for respectively threading suitable detonating cords through each end thereof. In operational burning series within said tubular housing are a plurality of lead sheathed protected explosives, a resilient pressure attenuating disc, a metallic capsule containing a calibrated delayed burning composition of 2/98B-Pb.sub.3 O.sub.4 having such geometrical configuration as to effect burning therealong for one-half second with considerable accuract, and another series of lead sheath protected explosives, a base charge, an explosive cord, and an end plug. An appropriate number of crimps are made along said tubular housing for holding the aforesaid elements in their proper places therein. Seals are employed at each end of said housing to make it watertight.

Abstract: Disclosed is a transistorized sonar transmitter which includes a power suy, a variable frequency, variable power, switching output stage, the switching of which is actuated by suitable drive signals from a control signal generator and amplifier. The power output from said switching stage is controlled by a time-ratio-control circuit which regulates the voltage thereof by means of a variable duration TRC drive signal from said control signal generator and amplifier, the duration of which is proportional to the power output thereof.

Abstract: A system for monitoring air-water borne noise generated by an aircraft flg over a body of water from within the aircraft includes a sonobuoy having a phase linear array of hydrophones suspended beneath the surface of the water and an electromagnetic radar transponder to permit accurate location of the surface position of the sonobuoy and a plurality of electroacoustic transponders to provide positioning information for the hydrophone array located in spaced relation from the first sonobuoy.

Abstract: An endoscopic photographic system includes the body inserted endoscope cocted via a fiber optic bundle to a photographic lens carrier in a focusing mount. The photographic lens is provided with a compound sliding mount which positions it on a camera back supporting a self developing film plate in the focal plane of the lens. By moving the compound mount, a plurality of photographs may be obtained on a single self developing plate such that timely diagnosis may be readily facilitated.

Abstract: An amp-hour monitor is provided to determine the power expended by a marine attery power supply system. Digital processing circuitry monitors a selected battery system and provides a readout of the power expended using a digital display. Additionally, a display of on-line current being drawn from the individual battery packs is displayed.

Abstract: An improved cable or chain cutting implement comprises a two piece body pion with sharpened cutting edges on one end thereof. The two pieces of the body portion are configured so as to encompass a towing or sweep cable in gripping relation thereto. A spring retaining member holds the pieces of the body portion in operative relationship to one another and the towing or sweep cable. A plurality of these cutting implements may be attached to a single towed sweep line to comprise an improved, high speed mine sweeping system.

Abstract: A tethered underwater work system comprises a primary lift module attached o a support vehicle by means of a primary tether. A submarine work vehicle is removably attached to said primary lift module and connected thereto by means of a secondary tether. Additionally, the lift module contains electrical distribution systems to permit an extensive control and instrumentation linkage with the submarine work vehicle and remotely controlled manipulators mounted thereon.

Abstract: A submarine power package converts direct current electrical energy to alnating current energy and is adapted to function while exposed to the high pressures of the deep ocean. A diode protection circuit and special semiconductor mounting arrangement makes this performance possible without the use of a pressure housing.

Abstract: A torque control system designed to economize on consumed fuel includes a source of motive power, a load and a transmission coupling the motive power to the load. A torque measuring device is attached to the output of the transmission and senses a torque applied to the load. The output of the torque sensor is compared with electrical analogs of optimized torque situations. The comparison results in the development of a control voltage which is applied to the source of motive power and the transmission to effect optimization of torque control.

Abstract: An apparatus and method for detecting the presence of, and severing command ables submerged in an aqueous medium, utilizing a galvanic current pulse generated by a galvanic cell with one electrode thereof serving as a cable cutter.

Abstract: An oceanographic flow sensor for use in component type electro-magnetic fmeters includes a pair of spaced electrodes and a conductive coil wound thereabout having a small enclosed area. A sensor construction is also disclosed having a plurality of mutually perpendicular coils. A preferred embodiment uses a conductive coil wound along a bent winding axis such that mutually perpendicular sensing electrodes may use the electromagnetically generated field from a single winding.

Abstract: An in situ refurbishing system for viewing ports aboard pressure-tight hu includes a guide shaped to cooperate with the viewing port and provide a datum axis centered thereon. An axle is rotatably supported by the guide and carries a lapping tool in polishing engagement with the port. Centering guides permit adjustment of the datum axis and pressure means exert a uniform engagement pressure with the lapping tool such that optical quality surfaces may be obtained without extensive dismantling and use of shipyard time.

Abstract: An improved power supply for alternate frame stereoscopic image presentat system includes a switch circuit for triggering two light valves mounted to present alternate left-right images to a viewer. A delay circuit using a variable pulse length monostable multivibrator permits the length of the "on" time to be adjusted to prevent light valve delays from introducing stereoscopic "ghosts".

Abstract: A recovery system for attaching a line to an underwater object includes a cially worn tool holder adapted to be carried by an underwater mammal which supports a surface engaging tool at the forward end thereof. A signalling mechanism is also included to be actuated on attachment of a tool to an underwater object.

Abstract: A portable submerged structure uses fluid pressure to extend a plurality of lexible conduits until the conduits become rigid. In such a rigid configuration the flexible conduits provide a rigid support which is independent of any further moorings or other conventional structure used to obtain rigidity. The invention discloses the use of an open form of independent conduits as well as conduits which are joined to provide a closed geometric figure. A packaging and deploying system using a fluid released container is also disclosed.

Abstract: An underwater hydraulic pressure regulator includes an ambient pressure ronsive cylinder and a regulator cylinder which are each fitted with integrally coupled pistons. The ambient pressure cylinder, as the name implies, is opened to ambient pressure by suitable ducting. The ambient pressure works against a volume of low pressure gas on the other side of a piston contained in the ambient pressure cylinder which in turn displaces the piston within the regulator cylinder. The back of the regulator cylinder is in communication with a conventional gas accumulator such that the restortative force on the back face of the second piston is influenced by both the ambient pressure and the gas accumulator pressure.

Abstract: A circuit for generating a discrete Fourier transform in real time employs a digital and analog shift register, each cell of which is tapped to feed an analog switch. The outputs of the individual analog switches are fed to a summing bus where the switched analog signals combine to form the desired Fourier transform.