Abstract: A low-density resin impregnated ceramic article advantageously employed as a structural ceramic ablator comprising a fired preform of ceramic fibers. The fibers of the ceramic preform are coated with an organic resin film. The organic resin can be a thermoplastic resin or a cured thermosetting resin. In one embodiment, the resin is uniformly distributed within the ceramic article. In a second embodiment, the resin is distributed so as to provide a density gradient along at least one direction of the ceramic article. The resin impregnated ceramic article is prepared by providing a fired preform of ceramic fibers; immersing the preform of ceramic fibers in a solution of a solvent and an organic resin infiltrant; and removing the solvent to form a resin film on the ceramic fibers.

Abstract: In a window structure equipped on the side walls of a cabin in the body of an airplane, a transparent board is mounted on the outer portion for sealing the pressure inside the cabin. A dust cover is mounted in the inner side of the transparent board sealing the pressure, and a shade 80 which is able to take an up and down movement is mounted on the cabin side of the dust cover for blocking outer incident light. The dust cover comprises of a transparent resin board and a non-elastic film stuck on the surface of the transparent resin board facing the shade. The acrylic resin used as the material of the transparent resin board expands by absorbing the water in the air, but by the operation of the non-elastic film, the dust cover bends toward the outer direction F of the body, and will not interfere with the locus L.sub.1 of the up and down movement of the shade.

Abstract: An aircraft structure, such as a wing, is made of fiber composite material and includes a shell structural component also made of fiber composite material. The structural component has at least one access opening closeable by a cover. The shell structural component has a first area containing the access opening closeable by the cover. In the longitudinal direction of the wing the first area is predominantly flexible while a second area surrounding the first area is predominantly stiff, whereby these areas take up different longitudinally effective forces, relative to the length of the wing. Both areas are capable of transferring shear forces in the same manner.

Abstract: A laminated body panel for aircraft applications comprises first and second metal layers and an adhesive layer. First and second sections in each metal layer are generally coplanar and separated by a splice line. A first splice line in a first metal layer is generally parallel to a second splice line in a second metal layer, and spaced laterally from the second splice line. An adhesive layer between the metal layers preferably contains reinforcing fibers bridging across the splice lines. An aircraft fuselage or wing or empennage made with spliced body panels of the invention has fewer joints and weighs less than one made with narrower body panels containing unspliced metal layers.

Abstract: Internal conformal antenna arrays are mounted in aircraft aerosurface and fuselage primary and secondary load carrying structures. These radar transmitting structures are dual role structures capable of efficiently transmitting and receiving radio frequency energy, and efficiently carrying and transmitting aerodynamic loads. The internal conformal antenna arrays are mounted in the leading and trailing edges of the wings, in the empennage, and behind the outer shell of the fuselage. In order to achieve radar transmitting structures capable of transmitting radio frequency energy and meeting primary aerodynamic load carrying requirements, ceramic, quartz, or silicone-carbide fiber-reinforced organic matrix composites are combined with advanced structures technology.

Abstract: An aircraft has the space between the bulkheads on the interior of the aircraft filled with a polyisocyanurate solid closed cell foam material. The foam is applied so that it adheres to both the inside of the aluminum skin of the fuselage and the facing sides of the bulkheads. The foam may be applied by either spraying or by pouring the resin with appropriate catalyst materials to cause the resin to form the foam. The foam acts to significantly strengthen the aircraft structure and thereby increase the time of usage of aging aircraft before the catastrophic failure of the adherence of the skin to the bulkheads.

Abstract: A method of constructing a carbon fiber composite wing in which upper and lower skins are bonded to a pre-assembled rib 15 and spar 16 framework, thus obviating the need for metal fasteners and hence cutting down assembly time. In one embodiment a novel cleat 17 of cruciform cross-section replaces the four cleats conventionally used for bolting the ribs 15 and spars 16 together. Holes 22 drilled in either end of the cleats serve as jig location points during framework assembly and anti-peel fastener holes after the skins have been bonded.

Abstract: A body that is adapted to contain a heat source such as a watercraft propelled by an internal combustion engine that is formed from heat sensitive polydicyclopentadiene. In order to protect the polydicyclopentadiene from deterioration due to oxidation caused by the heat, an insulating and protective layer selected from the groups of synthetic resins or synthetic rubbers is placed upon the polydicyclopentadiene at least adjacent the heat source. A preferred coating of epoxy resin is disclosed.

Abstract: A reentry body nose tip constructed from materials and produced by a proc such that shape stability is maintained under ablative erosion occurring during atmospheric reentry.

Abstract: A lightweight hybrid structural energy-absorbing panel having a plurality of layers of soft energy-absorbing material, such as Kevlar, disposed between facesheets with a plurality of rigid rod members extending between the facesheets through the layers of energy-absorbing material to structurally connect the facesheets, such panel to absorb the energy of ballistic projectiles.

Abstract: Disclosed is a woven fabric having a plurality of fabric layers which are integrated through combined portions formed by interlacing warps or wefts of one of adjacent layers of some of warps or wefts of said one layer and warps or wefts of the other layer or some of warps or wefts of said other layer with common wefts or warps, wherein a set of adjacent four layers comprises recurring structural units comprising (A) a part having one combined portion formed by intermediate two layers, (B) a first non-combined part having no combined portion, (C) a part having two combined portions formed by subsequent two layers, respectively, and (B) a second non-combined part having no combined portion. A honeycomb structure having cells of a shape of tetragons, hexagons or a combination thereof is formed among the entire layers when the multi-layer fabric is expanded. 40-100 wt. % of the fibers constituting the fabric are organic fibers which are infusible or have a melting point of at least 300.degree. C.

Abstract: A covering sheet material particularly for covering balsa wood frameworks of model aircraft, comprises a fibrous scrim which is impregnated with a resin solution containing a cross-linking agent and a catalyst. The resin solution may also include a dye or pigment, coloring agent, a filler or a metal powder, to give a desired surface appearance. The scrim may be a heat bonded non-woven fabric of polyester fibres, and the covering sheet may be bonded to the framework using a heat seal adhesive. After bonding, the covering material may be tautened by further heating. The covering material is lighter, stronger and more puncture resistant than conventional doped tissue paper covering materials.

Abstract: A transition fitting (16) for a high strength composite article (10) comprised of a matrixed skin (12) supported by and bonded to a core (14) to locate the same in an intended structural disposition subjecting the composite and fitting at or about a juncture thereof to bending and/or shear loads, comprising a profiled web (22) disposed within the composite article and a shank for fixturing the article, wherein the web includes a longitudinal aspect projecting into the core from the juncture to a tip of the web (26), a lateral aspect projecting across the core bounding the juncture, and a transverse aspect extending through the core; wherein the transverse aspect of the web tapers inwardly along the longitudinal direction of the web toward the tip and is dimensioned to provide load distribution to transfer structural loads from the composite to the fitting along a longitudinal force gradient having a minimum force value at the tip and a maximum force value at the shank, and yet further wherein the lateral aspe

Abstract: In a heat-insulating device comprising radiation-reflecting elements and a conduction-insulating material, the reflecting elements comprise a large number or reflecting flakes that are inserted into and distributed in the insulating material facing the surface through which the radiation has to be stopped. The said flakes are juxtaposed and partially overlap one another so as to conceal the said surface.

Abstract: A method is disclosed for creating a strong point for the attachment of carbon composites to metallic bodies that is suitable at high temperatures (1600.degree. F.) as well as ambient temperatures. A pocket of suitable dimensions and depth is molded into the carbon composite structure on both sides at an edge, with the edge relieved and rounded. A hole for a fastening member is molded or drilled in the approximate center of the pocket. After preparation of the surface the pocket, through hole, and relieved edge are nickel-plated to produce a rigid strong point. A doubler can be brazed to the nickel plate to strengthen the bond. The disclosed method can be used for attaching any type of electrically conductive composite material to a metallic structure.

Abstract: A component for cladding apertures in the fuselage of an aircraft is to be of lighter weight and more corrosion resistant as compared with known claddings. The component is manufactured of carbon fibre reinforced curable synthetic resin and comprises a base layer (2) onto which U-profiles (4, 4') and L-profiles (5, 5') are placed in spaced apart interrelationship, which during the manufacture are held in place by a grid (14) comprising angular bridge members. A vacuum foil (7) is applied over this assembly and is adhesively bonded along the edges of the base layer (2') to the supporting surface (1). The space between the vacuum foil (7) and the supporting surface (1) is evacuated and curing proceeds at an elevated temperature and pressure. After complete curing the vacuum foils (7) and the grid (14) are removed.

Abstract: A thermal insulating and/or sound absorbing structure comprising a batting of resilient, elongatable, non-flammable non-linear carbonaceous fibers, said fibers having a reversible deflection ratio of greater than 1.2:1, an aspect ratio greater than 10:1 and an LOI value greater than 40.

Abstract: A masking method which precisely controls porosity of a perforated titanium sheet having suction strips of a defined width includes separately taping suction strip areas and bonding land areas and then applying a coating of maskant material over the tape in the vicinity of the suction strips. Gaps formed on opposite sides of the suction strips are filled with the same maskant material and the bonding land tapes are removed after the masking material is semi-cured. The entire aerodynamic surface of the titanium sheet is covered with strips of tape and overlapping pieces of tape form seams in the vicinity of the bonding surface margins.

Abstract: Lightning protection apparatus for an exterior structural surface includes an electrically insulating protective coating adhered to the exterior surface, and a plurality of conductive particles supported in the coating. The particles are spaced at distances greater than the dimension of the particles in a direction parallel to the surface. The dielectric strength of the coating is thereby weakened by bridging the thickness of the coating with the particles. This enables lightning attachment to occur at a multiplicity of points rather than at one point, thereby reducing interior sparking in an aircraft and minimizing structual damage to the surface of the aircraft.

Abstract: A method of arresting delamination between and within plies of a composite laminate having layers containing a resin without significantly degrading the structural strength of the laminate characterized by emplacing within a plurality of the laminate layers having a resin, at a plurality of respective discrete locations, narrow strips of a tough adhesive having a fracture toughness greater than the fracture toughness of the resin in the respective layers of laminate. The adhesive has a Mode I critical strain energy release rate in the range of 5 inch pounds per square inch or more; for example, about 10 inch pounds per square inch. Also disclosed is a preferred method of constructing the laminate to employ this invention.

Abstract: Fiber reinforced resin composites formed by elements joined by a high shear strength, high fracture toughness adhesive are disclosed. The elements are created in easily produceable cross-sectional shapes such as flat, C-shaped, Z-shaped or T-shaped. When joined, the elements form delamination resistant fiber reinforced resin composites having more complex shapes. The strength of the junctions between a pair of elements, such as a panel and its associated reinforcing members, can be enhanced by fasteners, such as rivets, if desired.

Abstract: A lightweight building structure and method of fabrication is provided which is especially adapted for use in airline galleys or other interior vehicular constructions. It includes fireproof sandwich/core panels interconnected by plastic adhesive in a novel manner. The method of fabrication includes construction of the assembly in a clean environment, including forming and mating components in the panels, cleaning and deburring the components, adhesively interconnecting the panels prior to further cleaning prior to painting. The assembly is constructed in a manner to insure a completely smooth and continuous surface which enables ease of cleaning while preventing accumulation of dust and dirt.

Abstract: A load-bearing composite material structure (2, 2') has a plurality of layers of composite material. Each layer includes a matrix material (4) that maintains its structural integrity at 1200.degree. F. for at least five minutes. Preferred matrix materials are polyimide resins. Outer layers that will be directly exposed to a fire are reinforced with a woven fabric (8) that is sufficiently flame resistant and has a sufficiently fine weave to prevent flame penetration at 2000.degree. F. for at least fifteen minutes. The woven fabric (8) is preferably ceramic. The rest of the layers are reinforced with a fibrous material (6) to provide the necessary structural strength. The layers may be laminate cured together to form a single, integral structure (2) or such laminates adhesively bonded to a honeycomb (12).

Abstract: The present invention relates to fiber structures and methods for obtaining tuned response to high frequency electromagnetic radiation, particularly at microwave frequencies. In one embodiment, a woven fabric is prepared with ferrite filled fibers oriented perpendicular to dielectric filled fibers. The fill of the fibers is selected to reflect radiation having a known frequency and polarization. In other embodiments, tuned structures are provided by disposing sheets containing oriented ferrite and dielectric fibers parallel to one another and moving the layers relative to one another to achieve the desired impedance for incident radiation.

Abstract: High magnetic permeability composites are obtained by incorporating ferrite fibers in the composites. The ferrite fibers consist of a polymer and particulate ferrite fill at a concentration above the percolation threshold for the ferrite fill in the polymer (typically greater than 30 volume percent). The aspect ratio and ferrite concentration of the fibers are selected to minimize demagnetization fields in the fibers. The fibers can be dispersed in low concentration in an unoriented fashion in the composites to impart high magnetic permeability to the composite. In other embodiments, the fibers are oriented in the composites to impart high magnetic permeability to the composite for incident radiation of a particular linear polarization.

Abstract: A tubular circular cylindrical member, an attached frustro-conical member, and attached annular stiffening rings are formed of a metal matrix composite (MMC) material such as SiC/Al. The combined cylindrical and conical structure has a tapered wall thickness which reaches a maximum value at the point nearest the attachment of the structure to its launch vehicle. The entire structure and rings are quasi-isotropic, have a homogeneous microstructure, are low in weight, high in strength and stiffness, and are thermally stable with minimum distortion due to exposure to thermal cycling.

Abstract: Load-inducing armature adapted to be assembled with layers of fiber-reinforced plastic matrix to form a laminated structural element, whereby the portion of the armature intended to be embedded between plastic matrix layers is provided with through-holes having larger opening width than depth. In a completed laminated structural element pegs consisting of or amalgamatable with the matrix material connect the embedding plastic matrix layers through the holes in the armature for the introduction of load via the armature to the structural element with both ends of each peg subject to shearing stress.

Abstract: A fiberglass fabric wherein a selected number and pattern of yarns have been coated with an aluminum coating is preimpregnated with epoxy or other resin system and laid up as an integral part of a composite structure of the type having a honeycomb core and a plurality of fiberglass plies. Multiple plies of fiberglass fabric which include the yarns coated with an aluminum coating may be utilized in edgeband fastener areas for increased electrical continuity without loss of mechanical strength of composite parts.

Abstract: In a composite aircraft formed of graphite reinforced epoxy plates forming walls (14, 16) of the aircraft and walls of fuel tanks (12) therein, for example, there is an adhesive seal (36) for bonding overlapping faying plate surfaces together. The seal (36) is formed of spaced glass fibers (58) impregnated with a resin and with a filler of conductive material (50). The conductive filler is carbon in the form of approximate microspheres (52, 54), generally hollow, and having diameters in the range of 5 to 150 microns. The resin is cured on the faying surfaces after they have been secured together by fasteners (28) coated with a dielectric (30). The carbon microspheres (50) function to weaken the adhesive seal (36) between the plates (16, 22) so that they can be forcibly separated without structural damage to the plates.

Abstract: A fiberglass fabric wherein a selected number and pattern of yarns have been coated with an aluminum coating is preimpregnated with epoxy or other resin system and laid up as an integral part of a composite structure of the type having a honeycomb core and a plurality of fiberglass plies. Multiple plies of fiberglass fabric which include the yarns coated with an aluminum coating may be utilized in edgeband fastener areas for increased electrical continuity without loss of mechanical strength of composite parts.

Abstract: The dividing wall between a heat producing compartment of a helicopter, such as a compartment in which an engine or other power mechanism is located, and the pilot's cabin is made of a sheet of fiberglass that cannot withstand being subjected to an operating temperature that is in excess of about 200.degree. C. Accordingly, the hot side of the wall is lined with one or more liner blankets, each having a mineral fiber felt core, a metal foil front layer and a glass fiber fabric rear, supporting layer. These layers are quilted together and the result is provided with a binding about the periphery. The metal foil layer terminates somewhat short of the edge in order to make the margin more compressible. Each liner blanket is attached to the wall surface by a flexible adhesive. Where two or more of the blankets are used, they are placed so close together edge-to-edge that their respective margins are compressed, by abutment with one another preventing any unprotected gap.

Abstract: Although the method and apparatus of the present invention can be utilized to apply either a uniform or a nonuniform covering of material over many different workpieces, the apparatus (20) is advantageously utilized to apply a thermal barrier covering (64) to an airfoil (22) which is used in a turbine engine. The airfoil is held by a gripper assembly (86) while a spray gun (24) is effective to apply the covering over the airfoil. When a portion of the covering has been applied, a sensor (28) is utilized to detect the thickness of the covering. A control apparatus (32) compares the thickness of the covering of material which has been applied with the desired thickness and is subsequently effective to regulate the operation of the spray gun to adaptively apply a covering of a desired thickness with an accuracy of at least plus or minus 0.0015 of an inch (1.5 mils) despite unanticipated process variations.

Abstract: A fay surface sealing tool for applying sealant between wing skin and spar chord joints prior to fastener installation. The fay surface sealing tool includes a plurality of plurality of spaced apartures for dispensing the sealant in bead form between each row of fastener holes and on each edge margin subsequent to joint opening.

Abstract: In a method for at least partly metalizing the surface of a laminated component, the layer of material which is to form part of the surface of the component is first metalized; then it is coated, as are the other layers of non-metalized material, with a polymerizable resin; and lastly the coated layers are stacked on the lower part of a mould, which is then subjected to pressure, possibly under heat.

Abstract: Interlaminar shear strength of an aircraft wing made of graphite-epoxy laate is significantly increased by embedding thin steel wires in preselected locations of high stress in alternating rows .+-.45.degree. to the plane of the laminate before it is cured. This cross wire reinforcement prevents brittle delamination, arrests propagation of delamination and reduces scatter of interlaminar strength.

Abstract: A graphite containing composite structure having a fastener area for joining the composite to other structures terminates the graphite reinforced laminate adjacent to the fastener area. Kevlar reinforced laminates abut the graphite laminate and extend over the fastener area and are further reinforced with Kevlar laminates that overlap the graphite then extend over the fastener area.

Abstract: An elongate hollow structure with a plurality of reinforcements arranged in a pattern and acting as spacers between a pair of skins. The skins are of resin impregnated wound filaments with reinforcing strips of facing preimpregnated wound filaments that crisscross at the spacing reinforcements, abutting panels extend between adjacent reinforcing spacers to fill the space between the skins, and the structure is bonded with resin into a composite structure.

Abstract: An airfoil or wing is connected to the body of an aircraft or spacecraft through a main connector comprising metal and nonmetal components. Tension load take-up loops and a pressure load take-up core are arranged or held in a metal grommet which in turn is centered relative to and integrated with a main connector bushing. Thus, the tension loads are solely introduced into the wing structure through the tension loops and pressure loads are taken up solely by the pressure core, whereby the advantages of fiber compound materials are optimally utilized.

Abstract: A motorized model vehicle is formed of sheets of aluminum attached by heat soluble glue. The model has no internal supporting structure, but relies upon the resilient prestress of the metal sheet to maintain a desired shape. Methods of folding, forming, connecting and strengthening the parts of the aluminum body are disclosed.

Abstract: A recoverable remotely piloted vehicle (RPV) having: a deflectable canard/elevator placed very close to the nose tip; a constant (cross) section fuselage; wings mounted low and well aft on the fuselage; elevons; a centrally positioned weapons/payload bay, with doors, located internal of the upper portion of the fuselage; and, inflatable landing skids. The weapon/payload is dropped from the RVP, while the RVP is in flight in an inverted position.

Abstract: Construction parts are protected against lightening by a layer which releases a cloud of ionized and ionizable particles to spread the area affected by the lightening flash and to fan out the current path. The layer may include additives which swell when heated to increase the volume and density of the cloud. An electrically and thermal conductive layer or two such layers each having predominantly one of these properties is provided underneath the releasing layer.

Abstract: A coated fabric having a cured, synthetic elastomeric compound bonded thereto in a fashion to control the final weight and other physical and chemical properties thereof. The method comprehends the exposure of a fabric to an elastomer during its pot life to allow it to penetrate the fabric under "blotting" conditions and then quickly curing the elastomeric compound.

Abstract: A composite structure capable of withstanding multidirectional stress loads in general and in particular high tension and compression loads transmitted to an aircraft center fuselage by wing loading. The structure is essentially a beam formed by inserting two stepped metal end caps into the ends of a graphite/epoxy B-staged tubular strut and subsequently laying-up multidirectional and unidirectional fibers to provide a structure which is in turn cocured and results in a unitized composite wing trunnion structure.

Abstract: A three-dimensional composite structure with integral reinforcing ribs. The ribs have a core to include spaced metal inserts that are positioned to accept load bearing fasteners. A lightweight reinforcing material fills the remainder of the core. An adhesive tape with continuous filament composite fibers encircle the rib. The ribs are positioned between an inner and outer shell of structurally reinforced plastic and wound circumferentially and laterally with continuous filament composite tape.

Abstract: A method of finishing cloth-covered aircraft wings and fuselage. The cloth, cotton or polyester cloth of the type made from monofilaments of the condensation product of ethylene glycol with terephthalic acid or dimethyl phthalate is, after application thereof onto the airframe, coated with a layer of latex and dried, then coated with a second, or intermediate, layer of different coating and dried, and then coated with a decorative coating material. The use of latex as a first coat on the cloth results in substantial savings in labor and time and results in a coated fabric of superior flexibility integrity and durability.

Abstract: A functionally improved tape-like, heterogeneous, strip material for use in the fabrication of laminated structural shapes having high value of Young's Modulus and high tensile strength, comprising collocated, unidirectional, tectonic filaments such as graphite, boron, silicon-carbide, S-glass and E-glass, embodied in planar concourse, into an organic, thermosetting resin matrix or sheath such as an epoxy or polyimide base polymer forming a basal tract having at least one integral marginal tract of differing physical character so that a relatively lower Young's Modulus is exhibited by the material comprising the marginal tract than that exhibited by the basal tract. This difference in structural characteristic serves to provide an inherent arrestment barrier against fast rupture propagation of fractures which may develop in the basal tract material when the composite strip is subjected to sustained overload or external damage.