Abstract: An aircraft bypass turbofan engine subassembly for ground deceleration (e.g., thrust reversal). A fan nacelle has a through passageway connecting its inner exterior surface and outer exterior surface. A passageway end is located on the inner exterior surface aft of the aft-most row of fan rotor blades. A row of pivotable fan outlet guide vanes is located radially between the fan and core nacelles and longitudinally aft of the flow splitter and the passageway end. Apparatus is provided to pivot the vanes to block passage of bypass air and to open the passageway for ground deceleration.

Abstract: The discharge flow from a rotary vane pump is metered by directing a portion of the pump discharge back into the pump inlet area. A servo controlled actuator apportions the relative amounts of inlet fluid and returns fluid which enters the vane cavities. This arrangement allows for the use of a fixed cam which provides improved pump performance as compared to comparable movable cam pump designs.

Abstract: A superalloy component includes a substrate article of a superalloy, and a strengthenable, adherent coating on the substrate. The coating is preferably a nickel-base superalloy that is strengthened by the formation of gamma and gamma-prime phases. The coating is stronger than conventional MCrAlX coatings, and, therefore, more resistant to thermal fatigue. One operable coating has a composition, in weight percent, of about 7.5 percent cobalt, about 9 percent chromium, about 6 percent aluminum, about 1 percent titanium, about 1.5 percent molybdenum, about 4 percent tantalum, about 3 percent tungsten, about 3 percent rhenium, about 0.5 percent hafnium, about 0.3 percent yttrium, about 0.5 percent columbium, about 0.05 percent carbon, about 0.015 percent boron, about 0.015 percent zirconium, and balance nickel.

Abstract: A structural frame assembly for use in a gas turbine engine includes an annular inner hub, an annular outer casing and a plurality of circumferentially-spaced and radially extending hollow struts connected to the inner hub and outer casing. Hot gases are extracted from the engine primary flowpath, using a scoop attached to each strut, and are directed through the struts to the inner hub interior for the purpose of reducing a bulk temperature differential between the outer casing and the inner hub and for providing a uniform temperature distribution within the inner hub. A first portion of the hot gases entering the inner hub flows continuously through passages extending through the inner hub forward wall and scrubs an exterior of the forward wall, using an annular shield attached to the inner hub, before re-entering the engine flowpath.

Abstract: A free-floating damper system is provided wherein a damper housing is configured to receive a damper arm for free-floating movement in the x/y plane while restricting similar movement in the z plane. The damper arm is specially configured with first and second wear bushings positioned in a spring biased support to insure the frictional generation of coulomb dampening forces between the damper arm bushings and the damper housing. The damper can be fixedly mounted to a portion of a gas turbine engine such as the turbine frame and a portion of the damper arm can be attached through a mounting bracket to an accessory tube of the engine to dissipate vibrational forces which otherwise can damage the accessory tube.

Abstract: An eddy current device for inspecting a component includes an eddy current array circuit having respective pluralities of drive and sense elements and having an active face for positioning on a surface of the component during the inspection operation. A backing is disposed on a face of the eddy current array circuit opposite to the active face for concentrating an electromagnetic flux from the eddy current array circuit into the component when each of the plurality of drive elements is being energized. A mechanical arrangement is provided for supporting and deploying the backing and the array circuit to substantially conform with the surface portion under inspection and to cause each of the pluralities of drive and sense elements to be maintained at their respective substantially constant distances from the inspection surface during scanning, preferably at a controlled rate of scan.

Abstract: A thrust reverser for a long duct mixed flow fan jet engine having a nacelle formed by a fixed forward structure surrounding the fan, a rear fixed structure and a translatable inner and outer cowl therebetween, the nacelle surrounds the engine and forms a long by-pass duct therewith, a common actuator fixed to the translatable cowls to simultaneously displace them over the rear structure, blocker doors coupled to the inner translating cowls for deployment during thrust reversal into the by-pass duct into a blocking position to divert the airflow through the cascades placed into an opening uncovered when the translatable cowls are axially displaced.

Abstract: A composite fastener member, in one form, having integral head and shank portions is defined by a plurality of superimposed composite fiber reinforced sheets spirally wound about a longitudinal axis. A plurality of fastener members, oppositely disposed within an opening in an article, define a fastener especially useful in joining lightweight composite structures such as aircraft or aircraft engine components. In another form, the ends of a single spirally wound composite fastener member are splayed to fasten a plurality of sheets.

Abstract: A method and system for cooling a gas turbine engine in conjunction with an improved gas bearing face seal assembly. The gas turbine engine has a multi-stage compressor which discharges compressor discharge air for expansion by a combustor. A cavity which is aerodynamically linked to a turbine stage on its downstream end is formed by a metal structure the upstream end of which is connected to a seal which substantially inhibits the flow of compressor discharge air into the cavity. A conduit links an intermediate stage of the multi-stage compressor to the cavity for purposes of cooling the cavity and the turbine stage components located downstream of the cavity.

Abstract: A combined turbofan and ramjet aircraft engine includes a forward bypass duct which allows the engine to operate more efficiently during the turbofan mode of operation. By mounting a ramjet preburner in the forward duct and isolating this duct from the turbofan bypass air, a transition from turbofan operation to ramjet operation can take place at lower flight Mach numbers without incurring pressure losses or blockage in the turbofan bypass air.

Abstract: The invention provides a system, method, and computer program for automatically evaluating the linear displacement and inclination of the centerline of a piece of hardware to be machined on a computer numerically controlled (CNC) machine relative to an axis of rotation of the machine about which the hardware will be rotated. The invention also provides a compensation for correcting for any hardware axis misalignment.

Abstract: A rotor disk includes a rim with axially spaced apart forward and aft ends, with the aft end having a larger diameter than the forward end. The rim includes a plurality of straight dovetail slots defining dovetail posts therebetween. Each dovetail post includes a pair of lobes, a neck, and first and second pressure faces facing radially inwardly from the lobes. The first and second pressure faces vary in radial height therebetween from a first magnitude at the rim aft end to a second and smaller magnitude at the rim forward end to shift a portion of the bending loads from the dovetail post at the rim forward end to the dovetail post at the larger rim aft end.

Abstract: A gas turbine engine rotor blade includes an airfoil joined to a dovetail. The dovetail includes a shank from which extends two pairs of dovetail tangs being defined by a bifurcating slot disposed therebetween. The dovetail is configured for retention in a complementary dovetail groove in a rotor disk with the bifurcating slot remaining empty for reducing weight of the blade while transferring centrifugal loads from the blade to the rotor disk.

Abstract: A bypass valve assembly includes an outer casing and a spaced outer liner defining an annular bypass channel for channeling bypass air. The outer liner includes a plurality of circumferentially spaced slots around which are positioned an annular valve body. The valve body is positionable from a closed position substantially blocking bypass airflow into the slots to an open position uncovering the slots. Positioning means rotates and translates the valve body over the outer liner for covering and uncovering the slots.

Abstract: The present invention provides a brush seal having upstream and downstream plates that sandwich therebetween a plurality of bristles that sealingly contact a rotating member. The downstream plate includes primary and secondary backing rings with a flexible connection extending between the two rings so as to permit relative radial movement therebetween.

Abstract: An apparatus and method for the disassembly of an ultra high bypass turbine engine having an outer engine portion and an inner engine portion. A plurality of fan blades and acoustic panels are removed from the inner portion of the engine. The outer portion of the engine which includes a plurality of fan outlet guide vanes and fan casing are disconnected from the engine and axially removed. Certain outer portions of the engine including a hinged thrust reverser and hinged fan cowling may be coupled to an aircraft pylon and used interchangeably with replacement engines.

Abstract: A variable angle stator vane assembly for an axial flow gas turbine engine compressor. The compressor casing has a bore surrounded by a boss at the position of each assembly. A housing having a central bore and a bushing assembly is located in the casing bore and is bolted to the boss. The stator vane spindle extends through the housing bore and busing assembly. The housing and bushing assembly can be removed from the casing bore, to be rotated 180.degree. or replaced, without removing the casing from the compressor or the stator vane spindle from the casing bore.

Abstract: A counterrotating turbine support assembly includes outer and inner rotors having respective outer and inner blades disposed in an outer casing. A mid-frame is disposed forwardly of the rotors and fixedly joined to the outer casing. A rear frame is disposed axially aft of the rotors and is fixedly joined to the outer casing. A forward support shaft is joined at one end to a forward end of the outer rotor and is rotatably supported at an inner end to the mid-frame by a forward bearing. An aft support shaft is joined at one end to an aft end of the outer rotor and is rotatably supported at an inner end to the rear frame by an aft bearing. An intermediate support shaft is fixedly joined at one end to the inner rotor and is rotatably supported at an inner end to the mid-frame by an intermediate bearing.

Abstract: A gas turbine engine combustor is provided with a combustor dome plate film cooling means having an annular slotted ring to provide a film starting means upstream of a multi-hole film cooled single wall metal dome plate which is annular in shape. One particular embodiment provides a starting slot in the form of a plurality of rings surrounding the edges of the air/fuel nozzle inlet apertures in the dome plate. The cooling holes are disposed in concentric circles about the apertures and angled along radii emanating from the center of the apertures. This produces a cooling film emanating radially from the ring like circular slots around each air/fuel nozzle inlet aperture in the dome plate. Another embodiment provides a starting slot in the form of circumferential rails circumferentially disposed about the inner and outer circumferential edges of dome plate.

Abstract: Control of a gas turbine engine, suitable for powering an aircraft, is accomplished by varying outlet nozzle cross section and/or a mixing of bypass air with exhaust gas at an inlet to the nozzle. The engine includes a core engine having a combustion chamber and high and low pressure turbines followed by an exhaust plenum. High and low pressure compressors driven by the turbine assembly direct air into the combustion chamber and into a bypass duct. The bypass duct extends from an outlet of the low pressure compressor. Pressure of fluid (air or exhaust) is measured at an inlet to the high pressure compressor, in the bypass duct, and in the exhaust plenum. Ratios of the pressure of the duct pressure or of the pressure at the inlet of the high-pressure compressor, to the plenum pressure are employed in a feedback loop for control of nozzle size, and also of mixing valve position in an alternate embodiment of the invention.