Abstract: A method for bonding a thin metal sheet to a rigid body utilizes pneumatic cylinders compressing a spreader bar against components to be bonded. C clamps specially designed to hold the pneumatic cylinders are used to hold the components in place. Heat is applied to the bonding surfaces for curing for a predetermined period of time.

Abstract: An improved bifurcated multi-lever fiber optic transducer comprising one ht transmitting fiber and two receive fibers having different core diameters separated at one end and combined at the common distal end in the vicinity of a reflective surface parallel to the fiber end plane which is sensitive to axial motion caused by minute pressure changes, either in air or water, such that any displacement of the reflector from equilibrium will increase or decrease the illuminated areas of the two receive fibers which can be used to generate a processed output signal proportional to this motion. The resulting probe is of minimal diameter, has significantly improved sensitivity and produces an output independent of power variations at the input.

Abstract: A communications link between a submarine and a torpedo secured within a nch tube flooded with seawater. A transmit/receive light beam pair propagating through the water provides the high bandwidth data channels between the tube wall and the adjacent torpedo hull for two-way communication.

Abstract: A frequency independent constant beamwidth lens antenna concept is descri. The device may be configured in various ways such as with a cylindrical lens with a retina. The essential feature is that a twisted planar or hyperbolic paraboloidal phase or wave front is formed by the antenna which then in turn produces a frequency independent constant beamwidth beam in the far field of the antenna. Moreover, the frequency independent constant beamwidth beam may be steered or scanned in azimuth without moving the lens.

Abstract: A method for effecting repairs of the damaged components of a machinery in he field which would otherwise require high temperature treatment of the damaged components to form a metal-oxide epoxy joint in a shop. The method includes preparing a repair patch which includes a metal sheet with the metal oxide layer thereon, applying a thin high performance protective coating thereover, covering thereof with a sacrificial backing sheet and then curing the adherent-top coat backing sheet to form a highly durable bonded system which can be stored until needed. At the time of repair the backing sheet is removed by sanding or grit blasting and the adherent is applied to the structure to be repaired under ordinary temperature conditions.

Abstract: A method and apparatus for reducing noise from a near-field noise source sent together with signals from a far-field source. The method uses an adaptive shaping filter and a summer, in conjunction with a directional reference sensor and a primary sensor which have at least a common sensing element therebetween. The directional reference sensor situated between the near-field noise source and the far-field signal source, rejects the broad-band signal but accepts the broad-band noise and feeds this noise into a reference channel of the adaptive filter. The primary sensor accepts both the far-field signal and near-field noise with equally sensitivity. The primary sensor feeds into the primary channel of the adaptive filter. The adaptive filter system subtracts the noise in the reference channel from the signal-plus-noise in the primary channel, thus producing an output having a greatly improved signal-to-noise ratio.

Abstract: An Air Deployed Oceanographic Mooring when assembled for deployment has a ltitude of components suitable for separation by explosive bolts upon deployment of the system. A parachute system is connected to a surface buoy. The components that separate from each other upon deployment comprise a parachute system, a surface float, a subsurface buoy, an anchor shell and a bottom finder. All components except for the parachute system have interconnecting flexible lines upon deployment. A novel locking mechanism for limiting the paying out of the line between the anchor shell and subsurface buoy is triggered by the slackening of the line between the bottom finder and anchor shell when the bottom finder hits the bottom of the ocean.

Abstract: An interferometer inhibits a received low frequency acoustic signal that is elow the pass band of interest from appearing in the output. The interferometer has a conventional optical hydrophone in the signal leg to sense both the high and low frequencies of an acoustic signal. The reference leg has means for accepting a low frequency acoustic signal to modulate the coherent light path length while inhibiting the desired high frequency signal. On recombining the signals from both the signal and reference legs the low frequency signal appearing in both legs is canceled and only the high frequency signal appearing in the signal leg reaches the output. In an alternate embodiment the reference leg mandrel is placed internal to the sensor mandrel and provides a low frequency compensation chamber.

Abstract: The reaction of the lithium enolate of acetaldehyde, LiOCHCH.sub.2, with achlorocyclotriphosphazene, N.sub.3 P.sub.3 Cl.sub.6, lead to the series of (vinyloxy)chlorocyclotriphosphazenes, N.sub.3 P.sub.3 Cl.sub.6-n (OCH.dbd.CH.sub.2).sub.n (n=1-6). The nongeminal pathway is favored. These materials undergo homopolymerization reaction and can be copolymerized with a wide variety of organic monomers. The resulting polymeric systems incorporate certain properties such as fire retardancy and are chemically bonded to the polymer rather than an additive.

Abstract: A pivotable support mechanism for an aircraft rescue hoist or the like. The pright position provides sufficient structural strength to support objects to be lifted by the hoist. The swing-away position provides clearance for access to other equipment without requiring removal of the hoist from the aircraft.

Abstract: A pseudo-random noise generator (PRNG) or a hard clipped tonal is remotely mployed as an acoustic signal simulator for calibrating individual hydrophone channels of an acoustic array. The PRNG is employed to present a complete measurement of the channel gain and phase vs. frequency characteristics. The circuitry provides for synchronizing a channel hydrophone PRNG's to obtain gain and phase comparison of a single channel measurement. The hard clipped tonal provides the gain vs. frequency of the channel transfer function. In addition a binary signal is provided for changing the gain of the channel.

Abstract: A hybrid sealing member has a sleeve with an inner surface dynamic seal and an outer surface static seal. The inner surface of the sleeve utilizes a plurality of quad ring seals having sides with undulations. The outer sleeve surface has a groove that holds an O-ring seal. Backup rings can be provided for both the quad rings and the O-rings to prevent slippage of the rings.

Abstract: A dynamic pressure test unit is utilized to determine the yield point of a lask. For a period of time prior to the yield point being reached the ratio of the pressure vs. volume of water pumped into a test flask assumes a constant value. After reaching the yield point the volume indication increases at a faster rate than the pressure giving a negative slope to a line on a stripchart recorder that indicates the pressure divided by the volume of water pumped into the flask.

Abstract: An ellipticized singlet azimuth versus elevation optimized and aperture eemized nonspherical acoustic lens antenna of very low or even minimal F-number providing balanced astigmatism for wide angle acoustical applications in underwater sound is described. The acoustic lens has an elliptical periphery and surfaces defined by a system of nonlinear partial differential equations, the surfaces acting together to produce two perfect primary off-axis foci F and F' at a finite distance in back of the lens and two perfect conjugate off-axis foci F.sub..infin. and F'.sub..infin. in front of the acoustic lens at infinity; i.e., the lens simultaneously focuses energy from the primary foci F and F' into two off-axis parallel ray plane wave sonic beams directed towards infinity at equal but opposite angles with respect to the acoustic lens axis.

Abstract: An antenna is tuned in separate discrete frequency bands by changing the ctrical length of the antenna. PIN diodes are placed at predetermined locations on the antenna coaxial cable radiating elements. When it is desired to shorten the antenna for a higher frequency band use, the diodes are biased short circuiting segments of the antenna. When the lower frequency band use is desired, diodes are unbiased so that the diodes act like a very small capacitance shunted by a large resistance which is essentially an open circuit permitting the entire length of the antenna to operate.

Abstract: A long, continuous, constant diameter, neutrally buoyant oil filled line array hose without couplings comprising a plastic inner hose having a layer of conducting and/or optical fibers wrapped helically around and bonded to the outer periphery along the neutral axis thereof. A strength member layer is encased within and bonded to an outer plastic sleeve which covers the conducting layer. Sensors are placed within the inner hose cavity through incisions formed at predetermined locations, attached to the conducting layer, and sensor-conductor junctions are sealed with a waterproof coating; the incisions are then chemically sealed. The hose cavity is filled with an insulating oil providing a continuous, oil filled constant diameter, line array hose devoid of coupling members.

Abstract: A pipelined Fast Fourier Transform (FFT) processor is described for proceng continuous sets of N samples in a highly efficient manner. Within a single set of N inputs, the samples arrive in pairs (sample 0, and 1, 2 and 3, 4 and 5, etc.). This input sequence can be obtained from a sequential stream of inputs (sample 0 followed by smples 1, 2, 3, 4, etc.) by delaying the even numbered sample by one time unit. Alternately, the device could be made to operate on sequential samples within a set of N samples by internal pipelining of the arithmetic units. The device achieves high arithmetic unit efficiency while minimizing the memory required by allowing each arithmetic unit in the pipeline, with the exception of the last, to operate on the even or odd numbered samples first, after which it will operate on the remaining samples, which have been appropriately delayed and switched through shift registers and switches.

Abstract: Apparatus and method for discriminating against non-Gaussian noise. Analog signals from an array of sensors are converted to real and imaginary digital representations and processed such that non-Gaussian noise is separated from signals of interest. The processor uses estimates of Kurtosis and quantiles from either past or adjacent frequency components to construct non-linear elements, which are then used to process remaining signal data to improve the signal-to-noise ratio thereof by removing non-Gaussian noise therefrom.

Abstract: A source of coherent electromagnetic radiation capable of generating or amplifying waves in the centimeter, millimeter, and submillimeter wavelength range. An annular beam of gyrating electrons is produced which is then compressed to its paraxial position by means of a solenoid magnetic field around the wave-guide. This electron beam is also subjected to a transverse motion in an interaction region by a longitudinal rippled (wiggler) magnetic field. Such a field is generated by a periodic assembly of rings magnetized in the axial direction. The electron beam during its accelerated motion generates or amplifies coherent electromagnetic radiation in the centimeter, millimeter, or submillimeter range.

Abstract: A machine for winding, in a selected and consistent manner, a fiber optic lament on a compliant elastomeric mandrel, which assembly responds to acoustic waves by producing variations in diameter and light transmission characteristics of the fiber optic means. A motor rotates the mandrel at a selectable speed. A timing belt couples the mandrel rotation to a traversing mechanism supporting an optical fiber carrying reel and is adjustable to variably convert the rotary to linear motion. The shaft supporting the reel has brake means for adjusting the tension on the fiber. The fiber feeds over an idler roll which operates to count the number of meters of fiber wound on the mandrel, and then passes under a tension sensing roll. By varying mandrel rotation speed, traversing speed and reel drag, compliant hydrophone mandrels can have optical fibers wrapped therearound having many different fiber lay angles and fiber tensions, thus permitting production of hydrophones of desired characteristics.