Abstract: Cure and consolidation of a viscous thermoplastic resin, especially one that softens and melts at a high temperature, is improved by assisting autoclave pressurized momentum transport for compaction of the composite using high frequency, low amplitude acoustic vibration within the resin. The vibration induces shear thinning in the resin which promotes resin flow, achieves filling or collapse of voids, and assists consolidation of the composite preform. The vibration is produced with a "shaker table" formed from metal plates sandwiching piezoelectrical transducers. The "shaker table" is coupled to the layup mandrel. The vibration might also be produced as a transducer pad that overlies the preform on the mandrel.

Abstract: Apparatus for applying heat to a patch on a composite structure repair site includes a sealed bladder containing both a thermally conductive fluid and a heating element in thermal contact with the fluid. The heating element which comprises a flexible sheet having an electrical resistance wire uniformly placed thereon can be immersed in the fluid or otherwise in direct thermal contact therewith. Electrical power is applied to the heating element by conductors passing through the bladder surface. The heating element of disclosed structure can be attached to seal the bladder interior into two reservoirs, to permit fluid flow throughout the bladder or to form at least one outer surface of the bladder. Flexible supports can also be attached from the heating element to an interior bladder surface to maintain spacing between the heating element and the surface.

Abstract: A tooling concept uses a compliant forming surface for forming composite parts. The tooling concept utilizes a rigid support substructure that has a thin compliant forming surface. In the preferred embodiment of the invention, the tooling concept is used to form a composite sine wave spar. A preferred embodiment of the tooling concept includes upper and lower tool inserts and side tool inserts. The upper tool insert has a compliant forming surface that is located in between a rigid support substructure and the composite material used to form the composite part. Composite prepreg is laid up over a sine wave contour on the upper and lower tool inserts to form upper and lower U-shaped composite workpieces. The upper and lower tool inserts and workpieces are then brought together to form a sine wave I-beam. Radius fillers are then applied to the intersections between the upper and lower composite workpieces and cap strips are placed over the flanges of the joined composite workpieces.

Abstract: An end effector (30) adap ttachment to and accurate positioning by a robot is provided for positioning a channel-shaped workpiece (10) at a desired position and drilling an accurately located positioning hole in the work piece, even if the workpiece is curved or has a compound contour. The end effector (30) includes a conventional speeder assembly (68) with a taper that can be grasped by the robot and rotated for transfer of torque to the speeder assembly. A flange base (54) is attached to the speeder assembly (68) and has a central opening to accommodate a drill bit (67). A housing assembly (50) is slidably mounted around the flange base (54) through a linear bearing (109). An index shaft (32) is slidably mounted partially within the housing assembly (50) through a second linear bearing (110). A collet (36) is concentrically mounted slidably about the index shaft (32). The collet (36) is adapted to expand radially when it is forced over a wider portion (34) of the index shaft (32).

Abstract: The plasma descaling process of the present invention removes surface oxides selectively from structural metal surfaces, especially titanium and its alloys, and, with appropriate control of the reaction temperature, is self-limiting to avoid cracking problems otherwise associated with intergranular attack. In a preferred embodiment of the present invention, a fluoride plasma reacts with surface oxides on a titanium alloy to remove scale and alpha case in a temperature controlled chamber without attacking the underlying crystalline metal to cause intergranular attack. Properly controlled by regulating the chamber temperature, the plasma reaction terminates when the plasma has removed the surface oxides and encounters the underlying crystalline metal. The product is a metal surface free of scale and alpha case and free of intergranular attack. The plasma descaling process replaces conventional metal finishing processes, such as chemical milling or etching.

Abstract: A stowable module, i.e., a storage container, that provides storage space in the airplane without occupying revenue floorspace. The stowable module comprises an integrated feature of a sidewall lavatory. The stowable module stows inside a sidewall lavatory during ground, takeoff, and landing operations. During flight, the stowable module is deployed by a flight attendant into an adjacent doorway area so that the lavatory can be used by passengers and crew.

Abstract: Aliphatic tetraketimine of the present invention are a novel class of compounds represented by the formula: ##STR1## wherein Et is ethyl, Me is methyl, and R is a residue of an aliphatic diisocyanate. The tetraketimine is made by condensing a novel ketimine with a diisocyanate. The ketimine has a free secondary amine after a polyamine selected from the group consisting of:______________________________________ H2N--C2H4--NH--C2H4--NH2, H2N--C2H4--NH--C2H4--NH--C2H4--NH2, H2N--(CH2)6--NH--(CH2)6--NH2, or tris(2-aminoethyl)amine ______________________________________is reacted with a ketone.

Abstract: A magnetic field sensor which can be used as an active antenna is disclosed that is capable of small size, ultrawideband operation, and high efficiency. The sensor includes a multiplicity of magnetic field transducers, e.g., superconducting quantum interference devices (SQUIDs) or Mach-Zehnder modulators, that are electrically coupled in a serial array. Dummy SQUIDs may be used about the perimeter of the SQUID array, and electrically coupled to the active SQUIDs for eliminating edge effects that otherwise would occur because of the currents that flow within the SQUIDs. Either a magnetic flux transformer which collects the magnetic flux and distributes the flux to the transducers or a feedback assembly (bias circuit) or both may be used for increasing the sensitivity and linear dynamic range of the antenna.

Abstract: A magnetic field sensor which can be used as an active antenna is disclosed that is capable of small size, ultrawideband operation, and high efficiency. The sensor includes a multiplicity of magnetic field transducers, e.g., superconducting quantum interference devices (SQUIDs) or Mach-Zehnder modulators, that are electrically coupled in a serial array. Dummy SQUIDs may be used about the perimeter of the SQUID array, and electrically coupled to the active SQUIDs for eliminating edge effects that otherwise would occur because of the currents that flow within the SQUIDs. Either a magnetic flux transformer which collects the magnetic flux and distributes the flux to the transducers or a feedback assembly (bias circuit) or both may be used for increasing the sensitivity and linear dynamic range of the antenna.

Abstract: A method and apparatus for temperature activated protection of electronic components from interfering electromagnetic radiation comprising the step of shielding of a component with a thin film of superconducting material characterized by a critical temperature of at least 93.degree.K, and exposing the film to a temperature below the critical temperature. To allow transmissions to and from the component, the shield is converted to a window by heating the film to a temperature above the critical temperature.

Abstract: I improve the impact shock resistance of bonds between composite elements by including Z-pin reinforcement. I prepare stubbled composite structure by using peel plys over the appropriate surface of the composite during pin insertion using conventional processes. I then use the stubbled composite structure with padups, as necessary, to produce the Z-pin reinforced joint or bond between composite elements using any of adhesive bonding, cocuring, or thermoplastic welding.

Abstract: A double shear lap join is formed between metal and composite structure by welding Z-pins in the composite in the joint area to the metal tangs on the metal structure. The joint has modest strength but is less susceptible to shock damage than an adhesive bond or to notch effect crack propagation damage associated with fastened metal/composite joints.

Abstract: I improve the impact shock resistance of bonds between composite elements by including Z-pin reinforcement. I prepare stubbled composite structure by using peel plys over the appropriate surface of the composite during pin insertion using conventional processes. I then use the stubbled composite structure with padups, as necessary, to produce the Z-pin reinforced joint or bond between composite elements using any of adhesive bonding, cocuring, or thermoplastic welding.

Abstract: Thermomechanical and thermo-oxidative stabilities in resin composites across the range of aerospace "engineering thermoplastic" resins are improved by forming four crosslinks at each addition polymerization site in the backbone of the resin using crosslinking functionalities of the general formula: ##STR1## wherein Z= ##STR2## .beta.=the residue an organic radical selected from the group consisting of: ##STR3## R.sub.R =a divalent organic radical; X=halogen;Me=methylT=allyl or methallyl.G=--CH.sub.2 --,--S--, --CO--, --SO--, --O--, --CHR.sub.3 --, or --C(R.sub.3).sub.2 --;i=1 or 2;R.sub.3 =hydrogen, lower alkyl, lower alkoxy, aryl, or aryloxy; and.theta.=--C.tbd.N, --O--C.tbd.N, --S--C.tbd.N, or --CR.sub.3 .dbd.C(R.sub.3).sub.

Abstract: The morphology of multidimensional, thermally stable oligomers is combined with the inclusion of charge carrier linkages within the polymer arms to produce thermally stable advanced composites from cured oligomers that are conductive or semiconductive if suitably doped.

Abstract: A coated ceramic has alumina as an amorphous residue from an alumina sol containing alumina powder or and, optionally, a high emittance powder. The alumina powder alters the rheology and wetting characteristics of the sol to aid in forming the residue and increases the alumina concentration (% solids) in the residue. The high emittance powder radiates heat out of the residue and away from the ceramic when the coated ceramic is heated, such as during orbital reentry.

Abstract: A surface treatment, especially for titanium and aluminum alloys, forms a sol-gel film covalently bonded on the metal surface to produce strong, durable adhesive bonds between the metal and an organic adhesive without using toxic chemicals and while significantly reducing or eliminating rinse water requirements of traditional anodizing or etching processes. An aqueous sol containing an zirconium and an organosilane with an organic acid catalyst and alkoxyzirconium stabilizer is applied to etched or grit blasted substrates by dipping, spraying, or drenching, to produce bonds in a single application comparable in strength and performance to standard anodize controls. Parameters affecting performance include the sol composition, the Si/Zr ratio, the ratio of sol ingredients, the concentration of the sol, the carrier solvent, solution age, catalysts, surface pretreatment, application method, curing process, and primer used.

Abstract: A concentrating coverglass allows efficient power generation for providing higher specific powers by space power arrays with weight penalties being countered by combining the functions of a solar concentrator and protective coverglass into a single element. A preferred frustoconical lens achieves a concentration ratio of about 4.5 at a thickness of about 1.0 mm. Efficient space power arrays with relatively wide tracking angle tolerance of up to about .+-.5.degree. using these coverglasses permit heavier payloads in the satellite's operating systems over traditional satellite designs.

Abstract: A ceramic composite is provided comprising ceramic fibers, glass microballoons and/or diatoms, bound together with a ceramic reinforcing cloth with a sol-gel ceramic binder. The composite is particularly useful as a high strength, high temperature insulation material.

Abstract: Ceria is used to assure release between a metal workpiece and associated forming tooling in forming operations conducted at temperatures of 1500.degree. F. (816.degree. C.) and above.