Abstract: A dual frequency, synthetic aperture, sonar system includes a transmitter r projecting insonifying pings alternatively at first and second frequencies and a linear receiving array carried by a vehicle so as to receive returns from said pings. The first and second frequency returns are separated and subjected to processing in parallel channels where they are resolved into in-phase and quadrature components for subsequent phase-error correction, coherent addition, and synthetic aperture beamforming.

Abstract: A sonar system having a transmitting transducer adapted for being moved ag a predetermined path, a transmitter for energizing said transmitting transducer, an omni-directional receiving transducer spatially disposed behind said transmitting transducer, a sidewardly and downwardly looking receiving transducer contiguously disposed with said omni-directional receiving transducer, a receiver connected to the output of said sidewardly and downwardly looking transducer, a series connected detector, differentiator, delay, and time base generator coupled to the output of said omni-directional transducer, and a readout connected to the outputs of the aforesaid receiver and time base generator.

Abstract: A sonar system having a transmitter for successively broadcasting a pair of coustical signals having different frequencies, a programmer for determining the times said pair of signals are broadcast, a receiver for receiving said pair of signals after they have been reflected from a target, a programmer for effecting the conversion of said received pair of signals into a continuous unitary electrical signal having variable consecutive time periods which alternately contain the respective frequencies thereof, and a readout for displaying said continuous unitary electrical signal.

Abstract: A sonar system having a sonar transmitter which is programmed to broadcast wo sets of several increasing frequency signals, with the frequency gap between each set thereof sufficient to cause them to distinguish between deep and shallow water targets, respectively. A heterodyne receiver receives target echoes of said sets of several frequency signals and converts them to two sets of identical frequency signals which are then readout as a single continuous target display signal.

Abstract: An electronic barrier utilizes a bifurcated beam of wave energy to establ a barrier area having a null between the forks thereof. Objects encroaching on said beam cause a portion thereof to be scattered in the foreward direction. Suitable receiver equipment located remote from the source of the bifurcated beam and responsive to the foreward scattered beam is connected to provide an indication of said encroachment.

Abstract: A system for sweeping acoustic and magnetic mines or a combination of both s disclosed as comprising a pair of spatially disposed magnetic pipes that are held in their respective spatial dispositions by front and rear straps, and an acoustical energy generating pipe suspended between said front and rear straps by hinges in such manner that it is also disposed between said pair of spatially disposed magnetic pipes. A tractor vehicle moves all of the aforesaid pipes and their associated elements as a unit along a course intended to be cleared of acoustic and/or magnetic mines.

Abstract: The received signal from an acoustic echo detection and ranging system is mpared with internally generated signals indicating the focus of a variable focus transducer. Logic circuits in the signal comparison channel develop control voltages to focus said transducer upon a predetermined area from which said received signal originates.

Abstract: Method and apparatus for use in measuring SAR (Specific Absorption Rate) of persons subject to RF (radio frequency) radiation utilizes twin well calorimetry including first and second gradient-layer type calorimetry boxes the thermally conductive walls and cover of which contain a multiplicity of thermocouples the outputs of which are differentially amplified to provide a differential output. Identical body models that are thermally responsive to RF radiation are contained in the box wells and, after a period of thermal equalization outside the influence of the RF source, one body model is removed from its well and placed in the influence of the radiation in question while the other remains outside the influence. After a predetermined time period the irradiated model is returned to its well and the differential outputs is plotted over a time period. The area under the resultant curve is representative of total absorption from which can readily be calculated SAR.

Abstract: A swimmer distress signal of the smoke or flare type has an ignition system hich can be operated with one hand. A stab primer is activated by a sliding firing pin that is normally locked in position and protected by a metal cover. Upon withdrawal of the signal from a pouch, a lanyard pulls off the cover to expose and unlock the firing pin which has an enlarged head. A hit or force on the firing pin head drives it into the primer to ignite the display.

Abstract: An intershaft seal device between inner and outer coaxial shafts of a mulle spool turbine is characterized by a primary seal ring and carrier assembly that is keyed for rotation with, and axial movement relative to, the outer shaft with the primary seal ring running between races mounted on the inner shaft. A secondary seal ring is disposed between a cylindrical portion of the primary seal ring carrier and a tubular flange extending coaxially from the outer shaft and effects a balance of axial forces resulting from pressure zones separated by the seal device.

Abstract: A method for manufacturing bladed disks, or blisks, for turbines by press welding of blades or outer airfoil elements to blade stives or inner airfoil elements on a disk is characterized by the provision on the outer and inner airfoil elements of flanges of excess flash material having alignment holes for dowel pins that assure alignment of leading and trailing edges of the airfoil elements during pressure welding, followed by removal of the excess flash material and the included dowel pins.

Abstract: An externally mounted fire or explosion suppressing device for aircraft f tanks includes a bottle of pressurized fluid suppressant agent, the bottle having a primary duct ending in a seal disposed against the exterior surface of a tank wall. A secondary duct is disposed at an angle to the primary duct and carries a pyrotechnic charge that is detonated in response to an optically detected flash in the tank and explosively cuts through the seal and tank wall to release suppressant into the tank.

Abstract: An apparatus and method for rewarming hypothermia victims utilizes mutually nductive first and second helical coils supported in spaced relation around a subject's torso, the combination of coils and subject having a resonant frequency in the 2 MHz to 20 MHz radio frequency range. An automatic tuner couples an RF generator to energize the coils at the resonant frequency. A portable version utilizes flexible coils on an insulating and spacing jacket having a zippered opening with conductive teeth to complete coil turns.

Abstract: A bomb to bombrack attachment lug assembly engages in a keyhold slot of a actice bomb casing and includes a metal lug element and a plastic locator element that centers and releasably locks the assembly in the keyhold slot. The lug element has an eye portion, a stem and arms extending laterally from the stem, while the locator element includes a cylindrical body snapped onto the stem and arms and has laterally extending ears having retaining bosses that engage the slot.

Abstract: A reconfigurable, automatic test equipment system having a controller conted by a system bus to a plurality of IEEE-488 based instrument resource stations is characterized by automatic initialization capability including automatic address searching. Automatically initializable resource stations each include an initializing circuit cooperable with the controller and respective resource to zero in on successive characters of a unique identifier for each resource.

Abstract: A device for clamping a marker to a mine mooring cable upon severing by a tter utilizes a V-shaped body having a liner that is explosively deformed into clamping engagement with the cable in response to cutter actuation. A smoke flare is included and ignited to provide a prolonged locating signal.

Abstract: A resistance monitoring solid state circuit distinguishes between a minimum high resistance condition and a maximum low resistance condition by current mode switching of a pair of transistors the switching control voltages of which are established by bias resistor networks forming legs of a bridge, with the monitored resistance in one leg, the transistors switching current flow into one or the other of two logic signal generating paths that include opto-isolators for electrical isolation from utilization circuitry.

Abstract: A multi-engine helicopter fuel supply balance system effects automatic trfer of fuel from a larger tank to a smaller tank in response to low fuel level in the smaller tank when in automatic mode, and effects a transfer of a predetermined quantity of fuel between selected tanks by timed operation of a constant delivery pump when in manual mode.

Abstract: A minesweeping cutter device includes a tubular body closed at one end and aving a cable engaging recess at the other end, a barrel member reciprocable in the body by cable engagement to fire a chisel propelling charge. The chisel has its cutting edge spaced from the cable until the charge is fired so that a reliable cutting velocity is achieved before impact. An erecting vane has a sweep wire channel and is provided with a sliding gate on a guide rail that diverges angularly from the axis of the channel.

Abstract: A flexible fluid coupling and electrical bonding device includes a sleeve elastomeric material and a wire mesh bonding strip having its central portion embedded between layers of the sleeve wall laminations, with extra length portions of the strip folded back within the sleeve either against or embedded in the inner surface of the sleeve so as to be clamped against and effect electrical bonding between metallic duct ends when joined by the device.