Abstract: Methods for semisolid manufacturing of precision parts, turbine rotors for example, comprised of a plurality of high melting point alloys are given. Generally, a semisolid/thixotropic process is operated under vacuum utilizing a cooled mold. The process preferably comprises a vacuum chamber, inductive heaters to bring two or more high melting point slugs to either a solid or thixotropic phase, and a plunger that accelerates one or more high melting point solid slugs into one or more thixotropic slugs and then into a mold. Prior to heating, preconditioning at least one of the slugs to form a non-dendritic microstructure simplifies processing. The semisolid microstructure solidifies as the completed forged assembly cools. Thixotropic forging of a multi-alloy assembly achieves optimized properties in specific locations of the final product.

Abstract: A method of manufacturing a recuperator for a gas turbine engine comprises the steps of stamping a plurality of spaced integral ribs on a metal plate so as to define a plurality of high pressure channels, stamping a plurality of spaced integral ribs on a second metal plate so as to define a plurality of low pressure channels, joining said first and second metal plates to form a cell, and joining a plurality of said cells to one another.

Abstract: A recuperator for a gas turbine engine comprises a plurality of cells that are orientated in an annular array and attached to one another at only the radially inner edges thereof. Each cell comprises a high pressure plate having spaced integral ribs thereon defining a plurality of low temperature compressed air passages and a low pressure plate having a plurality of spaced ribs defining a plurality of high temperature exhaust gas passages.

Abstract: A jet aircraft has a generally conical front fuselage section, a cylindrical intermediate fuselage section defining a passenger compartment, a generally conical aft fuselage section, and a single vertical stabilizer. The aircraft's propulsion engines are mounted on pylons on the conical aft fuselage section with the air inlets thereof disposed entirely within a rearward projection of the lateral cross section of the intermediate fuselage section thereby to preclude the ingestion of foreign objects into the engines while minimizing the effect of boundary layer airflow. The exhaust nozzles extend rearwardly past the vertical stabilizer to minimize side line noise.

Abstract: An environmental control unit to supply cool dry air to an aircraft cabin has a plurality of bleed air sources from an aircraft engine compressor supplying working fluid to an air cycle cooling circuit. An electronic control computer having a plurality of inputs and selects a bleed air source depending upon cabin cooling and pressurization requirements. A speed control valve responsive to an output from the control computer, modulates the flow of working fluid through a turbo-alternator, thereby synchronizing the frequency of electrical power produced by the turbo-alternator with that of an aircraft engine alternator. The turbo-alternator supplies additional electrical power to the aircraft, thereby minimizing the deleterious effect of warm air bled from the engine compressor on aircraft performance.

Abstract: A fuel-air distribution manifold for a gas turbine engine having an annular combustor surrounds the shaft of the engine and comprises a gas distribution annulus surrounding an air distribution annulus having a plurality of fuel-air mixing channels radially aligned with nozzles on the gas annulus, respectively, and communicating with the engine combustor. A fuel duct conducts a gaseous fuel only to the gas distribution annulus and an air duct conducts air only to the air annulus.

Abstract: The instant invention generally relates to a forwardly swept wing 10 for an aircraft comprised of a pair of opposed single piece machined aluminum alloy wing boxes 20 and 40. Specifically, the invention provides for a forward swept wing construction utilizing known in the art computer numerical control machining techniques to produce an aluminum alloy wing 10 having an integral leading edge 24 thereby greatly reducing assembly time. A plurality of integral stiffeners 80 oriented at a forwardly swept angle of approximately 12 to 13 degrees between forward 62 and rear 64 spars provides for a wing 10 that minimizes the effects of aeroelastic divergence.

Abstract: A jet aircraft has a generally cylindrical fuselage section defining a passenger compartment and a generally conical aft fuselage section having a maximum lateral dimension substantially smaller than the lateral dimension of the fuselage section. A propulsion engine is mounted on the vertical stabilizer of the fuselage and has an air inlet disposed entirely within a rearward projection of the fuselage passenger compartment to preclude the ingestion of foreign objects into the engine.

Abstract: Methods for semisolid manufacturing of precision parts, turbine rotors for example, comprised of a plurality of high melting point alloys are given. Generally, a semisolid/thixotropic process is operated under vacuum utilizing a removable mold. The process preferably comprises a vacuum chamber, an inductive heater to bring a high melting point multi-alloy slug to a thixotropic phase, a supercooled mold comprised of a low melting point alloy or metal, and a plunger that accelerates and injects the high melting point slug into the low melting point mold. As the formed part cools, the supercooled low melting point mold heats up to its melting point upon which separation from the formed part occurs. Supercooling of the removable mold permits the use of thixotropic methods for high melting point alloys. Thixotropic forging of a multi-alloy assembly tailors its mechanical properties to achieve optimized properties in specific locations of the final product.

Abstract: A jet aircraft has a generally conical front fuselage section, a cylindrical intermediate fuselage section defining a passenger compartment and a generally conical aft fuselage section having a maximum lateral dimension substantially smaller than the maximum lateral dimension of the intermediate fuselage section. The aircraft's propulsion engines are mounted on combination vertical and horizontal stabilizers in spaced relation to the conical aft fuselage section with the air inlets and exhaust nozzles thereof disposed entirely within a rearward projection of the lateral cross section of the intermediate fuselage section to preclude the ingestion of foreign objects thereinto and maximize efficiency of boundary layer air flow.

Abstract: Methods for semisolid manufacturing of precision parts, turbine rotors for example, comprised of a plurality of high melting point alloys are given. Generally, a semisolid/thixotropic process is operated under vacuum utilizing a heated mold. The process preferably comprises a vacuum chamber, inductive heaters to bring two or more high melting point slugs to a either a solid or thixotropic phase, and a plunger that accelerates and injects a high melting point slug into the heated mold containing one or more solid or thixotropic slugs. The semisolid solution is eliminated as the completed forged assembly cools. Thixotropic forging of a multi-alloy assembly tailors its mechanical properties to achieve optimized properties in specific locations of the final product.

Abstract: Methods for semisolid manufacturing of precision parts, turbine rotors for example, comprised of high melting point alloys are given. Generally, a semisolid/thixotropic process is operated under vacuum utilizing a removable mold. The process preferably comprises a vacuum chamber, an inductive heater to bring a high melting point alloy to a thixotropic phase, a supercooled mold comprised of a low melting point alloy or metal, and a plunger that accelerates and injects the high melting point alloy into the low melting point mold. As the formed part cools, the supercooled low melting point mold heats up to its melting point upon which separation from the formed part occurs. Supercooling of the removable mold permits the use of thixotropic methods for high melting point alloys.

Abstract: A mechanical spacer for holding an inner pipe fixed in place within an encasing outer pipe in a multiple wall pipe assembly. The spacer functions in place of a bracket in a double wall-chimney pipe assembly. The unitary spacer requires no external hardware nor requires welding, screwing, riveting or the like step in the manufacturing or assembly of the pipe assembly.