Abstract: A multi-spool turbofan engine has a plurality of circumferentially spaced poppet valves with diverters secured thereto for precisely controlling bleed of combustion gas aft of the high pressure turbine whereby the high pressure spool operates at high idle RPM so as to power accessories and the low pressure spool operates at low RPM so as to minimize noise and fuel consumption.

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: The cylindrical compressor casing of a gas turbine engine has a plurality of radially inwardly and axially rearwardly opening anti-surge grooves disposed on a radially inner surface thereof whereby foreign objects ingested into the engine and entering the grooves are free to move axially rearwardly of the engine.

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 stream of primary gas flowing through a bi-stable thrust vectoring nozzle becomes attached to a first or second surface extending downstream of the nozzle, each surface incorporating one or more control ports for controlling to which surface the stream is attached, wherein relative to the longitudinal axis of the nozzle, the angle of discharge from the first surface is substantially different from the angle of discharge from the second surface, preferably with the first surface substantially aligned with the longitudinal axis of the nozzle. In one embodiment, a plurality of nozzles are arranged with the respective first surfaces substantially aligned with the longitudinal axis of the nozzle combination and each of the respective second surfaces arranged to laterally deflect a respective portion of the stream of primary gas in a respective direction along each of two orthogonal lateral axes.

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 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: 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.