Abstract: An adaptive cycle gas turbine engine is disclosed having a number of features. A fan arrangement is provided having counter-rotating fan stages, one fan stage is operable to be clutched and decoupled from the other stage. A high pressure compressor bypass is also provided. A clutch is provided to at least partially drive an intermediate pressure compressor with a high pressure turbine when the high pressure compressor is bypassed. A partial bypass of the high pressure turbine may be provided.

Abstract: In one embodiment, a gas turbine engine may include an accessory system integrated in a frame between a bypass flow path and a core flow path. A shaft may be provided between the accessory system and a core shaft of the gas turbine engine. The integrated accessory system may include power devices such as motors and generators, among other types of devices. The gas turbine engine may have more than one device spaced at various circumferential locations. In one non-limiting example, two power devices may be spaced 180 degrees apart. In some embodiments, a shaft and gearing may be provided to a location such as a frame in preparation to receive a power device at a later time.

Abstract: In one embodiment a centrifugal impeller has an axis of rotation, a plurality of blades, and a plurality of pitches defined between the blades. A cavity may be formed in a back side of the impeller, opposite with at least one of the plurality of pitches. In one form the cavity may not extend below a radius determined according to a stress criteria or stress limitation.

Abstract: A gas turbine engine having speed an intermediate stage booster configured to provide speed change to a boost compressor. The boost compressor and fan stage are driven by a low pressure turbine; the fan stage rotates with the low pressure turbine shaft and the boost compressor rotates counter to the low pressure turbine shaft. The intermediate speed booster has an epicyclic gear train that includes an outer annulus, a sun gear, and a planetary gear, and may be engaged by a clutch in some embodiments.

Abstract: A thrust-producing engine includes an engine structure, a rotor that is electrically isolated from the engine structure, and an electrical conductor connected to the engine structure. The electrical conductor is in electrical contact with the engine structure and the rotor as the rotor rotates relative to the electrical conductor and the engine structure to reduce electrical arcing between the engine structure and the rotor.

Abstract: A turbofan engine blade retainer for use in retaining a fan blade to a fan disk. The blade retainer includes a fore blade retainer for limiting forward movement of the fan blade and an aft blade retainer for limiting aft movement of the fan blade. The fore blade retainer engages a fore portion of the fan blade and the aft blade retainer engaging an aft portion of the fan blade.

Abstract: A low leakage, integral fixed vane system for a gas turbine engine compression system which can accommodate the latest 3-D aerodynamic airfoil geometries and provide endwall ovalization control. A unitized construction wherein the vanes are integral with the case wall in the compression system.

Abstract: A method for mechanically cutting a continuous circular shaped groove in a foil sheet for use in a metal matrix composite product. In one form the foil sheet is held adjacent a rotating machine tool by vacuum and a cutting tool is moved relative thereto to cut a spiral groove.

Abstract: A compression system endwall bleed system having a plurality of bleed slots formed in a mechanical housing downstream of a rotating shrouded rotor. In one embodiment, the plurality of bleed slots bleed off a separated tip boundary layer to relieve back pressure associated with this blockage. A sealing structure downstream of the shrouded rotor is utilized to minimize working fluid leakage ahead of the plurality of bleed slots.

Abstract: The present invention contemplate a seal assembly for reducing the passage of fluid between a combustor liner and a turbine vane segment in a gas turbine engine. In one embodiment, the turbine vane segment has a lip portion defining a sealing surface. A seal element having first and second seal portion is coupled to the turbine vane segment by a support element. The support element urges the first seal portion into engagement with an aft edge of the combustor liner and positions the second seal portion adjacent the sealing surface of the turbine vane segment, while allowing relative movement between the second seal portion and the sealing surface in a direction substantially parallel to the sealing surface.

Abstract: A system includes a gas turbine engine having a shroud and a rotor with one or more blades. The rotor rotates within the shroud to pressurize a fluid during operation of the engine. An electromagnetic actuator is also included that is operable to move the shroud relative to the rotor to adjust clearance between the shroud and blades. In addition, a controller is included in this system to determine a desired amount of clearance in accordance with an operating mode of the engine. The controller generates an actuation signal to change the clearance in correspondence with the desired amount. The electromagnetic actuator responds to the actuation signal to provide the desired amount of clearance.

Abstract: The attachment of the blade to the disk of a gas turbine engine includes a sloped deep slot formed in the rim of the disk for accepting the dovetail of the root of he fan or compressor blade allowing the removal of a single blade from the disk and includes a segmented retainer plate disposed at the aft end of the bearing against the blade root to react out the slope induced axial blade loads providing a low hub-tip ratio configuration. A blade support disposed between the live rim of the disk and the bottom of the blade serves to support the blades radially during non-operating conditions and includes pockets for retaining weights for dynamic balance of the rotor. A forward mounted snap ring prevents forward movement of the blade during non-operating conditions.

Abstract: The span of the overhung flanges at the rim of the disks of gas turbine engine's compressors are minimized by slotting the one of the adjacent flanges at the distal end to receive the bolt head of the attaching bolt and including an anti-rotational clip allowing the nut to be fastened without the necessity of holding the bolt head. The complementing flange of the adjacent rotor includes mating holes. The anti-rotational clip includes bendable tangs bent in situ to engage the flats of the bolt head and a bent tang to fit snugly into the when radially inserted therein slot.

Abstract: In a gas compressor engine, a rotor to which turbine blades (airfoils) are mounted, is constructed of a fiber composite material. In a first zone of the rotor, a first group of fibers are oriented circumferentially, in the direction of rotor rotation. A second set of fibers are oriented off-axis along the entire longitudinal length of the rotor. The first group of fibers overlay the second group only in specific zones, creating zones in which only the off-axis fibers are located. Race-track shaped apertures are cut in these second zones between fibers and these apertures receive the compressor blades that are inserted from the interior of the rotor. The first zones also provide circumferential seals to receive the base of each compressor blade. The first zones are constructed by building up layers of the circumferential fibers in the first zones.

Abstract: A lightweight, integrally bladed rotor has airfoils (18) and a full hoop blade platform (26), a support ring (28) is inside and spaced from the platform, with radial webs (30) extending from the support ring to the platform. Each web is a radial extension (32) of an airfoil. A radially extending shear plate (36) is secured to the platform and the ring.

Abstract: A bladed turbine disk has a plurality of air cooled blades. The disk has a substantially continuous impervious rim. Each blade has a platform and an impervious base with the cooling air inlet between the platform and base. Each blade base is diffusion bonded to the rim, preferably to a slightly raised plateau. The edge of the bond surface is accessable and free of stress concentration.

Abstract: A latch for releasably maintaining a terminal block in an installed position in a panel aperture includes a U-shaped frame, guides on the terminal block at a leading edge thereof integral with the distal ends of the parallel arms of the frame supporting the latter on the terminal block in cantilever spring fashion and defining a lead-in surface in longitudinal profile, and a latch arm supported on the frame between the support arms in cantilever spring fashion including a ramp at its distal end extending from above the frame to inboard of the lead-in surface. As the terminal block approaches the installed position, the guides facilitate final movement thereto while the relationship between the ramp and the lead-in surface insures that the edge of the aperture will engage the latch arm only on the ramp thereby to prevent misengagement between the latch arm and the panel.

Abstract: An electrical terminal has a flexible contact bow which is integrally connected to an end of the rigid planar base by a curved nose bend. The contact bow has resilient, two-point support means at the opposite end which comprises a curved tail bend and an L-shaped support disposed between the contact bow and the rigid planar base. The L-shaped support includes a depending leg which slidably engages the rigid planar base to provide a first support point for the contact bow. The curved tail bend engages the rigid planar base after the depending leg engages to provide a second support point for the contact bow.