Abstract: A method for making an offset corrugated core sandwich construction is diosed. Mandrels of preestablished form and size are arranged into a pattern in a confined area. After covering the mandrels with a release film, strips of pliable, uncured composite material are arranged in a "peak-to-valley" pattern with adjacent strips being out of phase by 180 degrees. Selected mandrels are replaced by a granular mixture and top and bottom face sheets are fitted to the arrangement. After curing, all mandrels are removed from the construction.

Abstract: Apparatus is provided to detect electromagnetic radiation, in which a radion-absorbing element is disposed on a short section of an optical waveguide to provide a thermal interface therebetween. Radiation is absorbed by the element, which thereby heats the waveguide, causing it to change its optical pathlength in proportion to the radiation absorbed. Interferometer apparatus is connected to measure this change in optical pathlength as a change in the interference condition. This device is highly sensitive and can be operated at room temperature.

Abstract: The present invention is a method and system for performing optical filteg. Light energy in one frequency band is received in this system. The received light energy is filtered in one frequency band in order to provide filtered light which is applied to a nonlinear optical device. The nonlinear optical device provides frequency conversion preferably by forming a sum frequency or difference frequency. The frequency converted light energy is in a second frequency band. The energy in this second frequency band is applied to a further filter in a different frequency band wherein the two filter frequency bands are selected to prevent light energy from passing through both filters. The received light energy may contain information which is recoverable from the light energy which passes through the second filter. The nonlinear device is a crystal in which the index of refraction may be changed in order to tune the filter.

Abstract: A laminated structural component with superior resistance to flexural vibions is provided comprising two load-bearing layers and a viscoelastic damping layer sandwiched therebetween. Each of the load-bearing layers comprises an outer stiffness sublayer and an inner compliant sublayer, the compliant sublayer being positioned between the outer stiffness sublayer and the viscoelastic damping layer. The compliant sublayers have an extensional elastic modulus which is less than that of the stiffness sublayers, and greater than that of the viscoelastic damping layer. The laminated structural component experiences greater relative in-plane displacements between the load-bearing layers, and preserves transverse static stiffness.

Abstract: A lightweight corrosivity sensor is provided which is thin enough to be edded between the layers of a composite structure or placed on a surface beneath a coating. It comprises a thin non-conductive base and two electrically isolated conductive elements fixed to the surface thereof. Each conductive element comprises a bus bar and a plurality of strips extending from the bus bar and interdigitated with the strips of the other conductive element. The corrosivity sensor is connectable to a current measuring means for measuring the current across the two conductive elements as an indicator of the presence of a corrosive environment. A masking method of manufacturing such a sensor is also provided.

Abstract: A wavefront simulator that emulates plane wave propagation from multiple nsmitting antennas is used to evaluate, in both a static and a dynamic manner, an array processor used in RF communications to determine the location of transmitting antennas and possibly to perform beamforming for cancelling the energy of an interfering transmitter. The wavefront simulator generates time delay signals, giving the appearance of being emitted from different transmitters or sources, and simulates those signals as being received by an antenna array associated with the array processor. The array processor utilizes the time delay signals to calculate, e.g., the angle of arrival of the signals from the emitting antennas.

Abstract: A lift enhancing device for a solid wing is disclosed. A solid wing with a wept leading edge and unswept trailing edge has a rectangular flap attached along the trailing edge. The flap can be a single segment or can be a plurality of segments joined at contiguous edges. The flap oscillates during air movement and enhances the lift produced.

Abstract: A Josephson break junction device suitable for highly sensitive electronic detecting systems. A superconductor film such as YBa.sub.2 Cu.sub.3 O.sub.7 is deposited on a substrate such as a simple-crystal MgO. The film is fractured across a narrow strip by at least one indentation in the substrate juxtaposed from the strip to form a break junction. A transducer is affixed to the substrate for applying a bending movement to the substrate to regulate the distance across the gap formed at the fracture to produce a Josephson turned junction effect. Alternatively, or in addition to the transducer, a bridge of a novel metal is applied across the gap to produce a weak-link junction.

Abstract: Ship's attitude parameters, including pitch, roll and heading, provided in he form of synchro signals by redundant sensors, are distributed to various shipboard systems by a synchro selector binary switching tree under the control of a digital processor. The processor also generates dynamic simulations of pitch, roll and heading, which can be distributed to the shipboard systems by the switching tree.

Abstract: A lightweight corrosivity sensor is provided which is thin enough to be edded between the layers of a composite structure or placed on a surface beneath a coating. It comprises a thin non-conductive base and two electrically isolated conductive elements fixed to the surface thereof. Each conductive element comprises a bus bar and a plurality of strips extending from the bus bar and interdigitated with the strips of the other conductive element. The corrosivity sensor is connectable to a current measuring means for measuring the current across the two conductive elements as an indicator of the presence of a corrosive environment. A masking method of manufacturing such a sensor is also provided.

Abstract: A corrosion-resistant coating which can be applied directly to a surface as self-priming topcoat comprising a polyurethane resin binder and a combination of pigments consisting essentially of a molybdate-modified zinc phosphate, zinc salts of benzoic acids, and an alkaline earth metal phosphate such as zinc-barium phosphate. In addition, the coating contains up to about 35 parts by weight of a titanium dioxide pigment, up to about 3.0 parts by weight of an oil soluble dispersant agent and up to about 50 parts by weight of at least one organic solvent.

Abstract: A submarine-launched, ice-penetrating sonobuoy is disclosed. The buoy is pedo-shaped with a collapsible obturator tail-fin section removably attached at the tail-end, standard electronics in a mid-section and an explosive nose cone at the front. Immediately after launch, the tail-fin section expands to exert a drag on the buoy to halt any forward motion. The tail-fin section is discarded and the nose cone and mid-section portion rise until the nose impacts the underside of the ice. Upon impact, a pre-selected "shape" charge ruptures the ice and an a spring-antenna, connected to the mid-section, is raised through the hole.

Abstract: Corrosion resistant coatings are formed on aluminum by immersion in aqueous olutions containing chromic salts, a fluoride ion from compounds such as a fluosilicate with an alkali added near or slightly beyond the precipitation of the insoluble basic compounds. Trivalent chromium films formed on the aluminum surface when tested in 5% NaCl salt spray chamber showed corrosion resistance in excess of 96 hours. After a post-treatment with peroxide or permanganate solutions, the corrosion resistance for the aluminum substrates exceeded 168 hours. Trivalent chromium coated aluminum serves as an effective base for paint primers. Anodized aluminums were also afforded excellent corrosion resistance, after being treated in dilute/basic chromic sulfate solutions and post-treated with peroxide.

Abstract: A linear acceleration sensing device operates through a fluid medium. A fd signal output represents a differential pressure from the elastic deformation of a fluid-filled diaphragm or bellows assembly. A pair of fluid proximity sensors operate differentially in a fluid control network and detect the elastic deformation of the diaphragm assembly caused by increased hydrostatic pressure resulting from a change in acceleration, or "g" force.

Abstract: A corrosion-resistant coating which can be applied directly to a surface as self-priming topcoat comprising a polyurethane resin binder and a combination of pigments consisting essentially of an alkaline earth metal metaborate, zinc salts of benzoic acids, and an alkaline earth metal phosphate such as zinc-barium phosphate. In addition, the coating contains from 5-40 parts by weight of a titanium dioxide pigment, up to about 3.0 parts by weight of an oil soluble dispersant and up to about 50 parts by weight of at least one organic solvent.

Abstract: A corrosion-resistant coating which can be applied directly to a surface as self-priming topcoat comprising a polyurethane resin binder and a combination of pigments consisting essentially of a molybdate-modified zinc phosphate, zinc salts of benzoic acids, and an alkaline earth metal phosphate such as zinc-barium phosphate. In addition, the coating contains up to about 35 parts by weight of a titanium dioxide pigment, up to about 3.0 parts by weight of an oil soluble dispersant agent and up to about 50 parts by weight of at least one organic solvent.

Abstract: A corrosion-resistant coating which can be applied directly to a surface as self-priming topcoat comprising a polyurethane resin binder and a combination of pigments consisting essentially of an alkaline earth metal metaborate, zinc salts of benzoic acids, and an alkaline earth metal phosphate such as zinc-barium phosphate. In addition, the coating contains from 5-40 parts by weight of a titanium dioxide pigment, up to about 3.0 parts by weight of an oil soluble dispersant and up to about 50 parts by weight of at least one organic solvent.

Abstract: An on-demand wing vortex control system includes a pair of retractable pas which extend forward through slots in the leading edges of the strake and main wing at their junction. When not in use, the device is retracted in a stowed position, thus having zero impact on the cruise efficiency and observability characteristics designed into the aircraft. The panels extend forward from the strake and wing, providing an added leading edge airfoil surface when in the deployed position. Both panels are slideably and rotatably affixed to the aircraft. A front panel is affixed to and supported within the strake, while a rear panel is affixed and supported within the main wing. The planform of each panel is symmetrically identical, and the movements of the panels are mechanically coordinated so that the exposed planform shape represented by the combined overlapping panels are symmetrical about a line which bisects the strake/wing junction angle.

Abstract: A parallel plate dielectric viscometer is provided for measuring the viscty of a substance having differing substance dielectric properties at differing substance viscosities. Two electrodes are disposed in opposition to each other forming a variable dielectric cell having a dielectric distance between the electrodes. The viscosity of the substance is varied and force is applied to the substance to vary the dielectric distance according to the varying viscosity. The rate of change of the dielectric distance with respect to time is used to determine the viscosity of the substance. The viscosity may be varied by heating the substance and force may be applied to the substance by way of one of the electrodes such that the dielectric distance between the electrodes decreases as the substance becomes more viscous. A fixed cell may also be provided in order to correct for the effects of chemical changes in the substance.

Abstract: A process for preparing a stainless steel surface for bonding to an adhes is described. First, the surface is wiped with a solvent and then soaked in an alkaline bath at an elevated temperature to remove dirt and grease. The surface is then rinsed with water and immersed in a 135-.degree.F. to 145-.degree.F. solution containing from 25 to 35 volume-percent sulfuric acid in water for a period of time equal to the length of time it takes for a reaction on the surface to commence plus about 4 to 8 minutes. Next, the surface is immersed in a solution at ambient temperature containing from 28 to 35 volume-percent nitric acid and from 2 to 3 volume-percent hydrofluoric acid in water for about 4 to 8 minutes, and then rinsed with water and dried.