Abstract: Plated polymeric gas turbine engine parts and methods for fabricating lightweight plated polymeric gas turbine engine parts are disclosed. The parts include a polymeric substrate plated with one or more metal layers. The polymeric material of the polymeric substrate may be structurally reinforced with materials that may include carbon, metal, or glass. The polymeric substrate may also include a plurality of layers to form a composite layup structure.

Abstract: A method of protecting a blade of a gas turbine engine by applying a nanocrystalline metal coating to a portion of the blade root is disclosed, which includes preparing at least a portion of a dovetail of the blade root for coating; and then applying a nanocrystalline metal coating to said portion.

Abstract: Plated polymeric gas turbine engine parts and methods for fabricating lightweight plated polymeric gas turbine engine parts are disclosed. The parts include a polymeric substrate plated with one or more metal layers. The polymeric material of the polymeric substrate may be structurally reinforced with materials that may include carbon, metal, or glass. The polymeric substrate may also include a plurality of layers to form a composite layup structure.

Abstract: A gas turbine engine having a coupling element for coupling a first shaft to a second shaft, the second shaft being substantially axially aligned with the first shaft, the coupling element provided with an exterior surface that engages an opposing interior surface of the first shaft and an interior surface that engages an opposing exterior surface of the second shaft to facilitate torque transfer between the first shaft and the second shaft when rotated together, wherein the coupling element and at least one of the first and second shafts cooperate to define at least one fluid passageway therebetween.

Abstract: A fan rotor for a gas turbine engine has a fan hub mounted for rotation about a central axis of the engine. A plurality of fan blades are circumferentially distributed about a radially outer surface of an outer rim section of the fan hub. The outer rim section is connected to an inner rim section through an axially facing web section. The web section extends from the outer rim section at a location axially aft of the center of gravity of the fan blades. A ridge formation extends radially inwardly from the outer rim axially forward of the web section.

Abstract: A fan rotor has a fan web and a plurality of circumferentially spaced-apart fan blades extending radially outwardly from an outer rim of the fan web. The outer rim is integrally connected to an inner rim through an axially facing web section. The web section has an inward concavature and extends aft of the center of gravity of the fan blades to shift the center of gravity of the hub rearwards while maintaining airfoil stress below critical levels. The rim section may have an inwardly projecting annular channel formed in a leading edge thereof and tuned to the 2M3ND mode of the fan hub.

Abstract: A gas turbine engine having an electric generator includes a transmission shaft extending along a longitudinal axis of the engine and drivingly interconnecting a turbine shaft of the engine and a rotor shaft of the electric generator. The transmission shaft is engaged by splined mating connections with the turbine shaft and the rotor shaft. The transmission shaft has a shear neck defining a reduced radial wall thickness with respect to a remainder of the transmission shaft such as to provide a weakened region of the transmission shaft. An annular support structure, concentric with and surrounding the transmission shaft, is axially located between the shear neck and a forward end of the transmission shaft engaged to the turbine shaft, and includes a bearing operable to rotationally support the transmission shaft.

Abstract: A system for cooling a generator mounted in the tail-cone of an engine. The system comprises a fairing, which receives through an inlet thereof air from a bypass duct and directs the bypass air towards a cavity of the tail-cone for cooling the generator. The bypass air is then expelled through an outlet of a support strut positioned in fluid communication with the tail-cone cavity. The fairing inlet and the strut outlet are both positioned in a plane substantially perpendicular to a longitudinal plane of the engine. In this manner, circulation of the bypass air through the fairing, the tail-cone cavity, and the strut may be achieved. The bypass air directed through the fairing further enables cooling of service lines accommodated in the fairing. A lobe mixer is further used to direct the fairing and shield the latter from core exhaust.

Abstract: Devices and methods for supporting an accessory (32) in a gas turbine engine (10) are disclosed. The accessory (32) may have an interface (36) for coupling to a shaft (24) of the gas turbine engine (10). The device may comprise a first support (38) configured to support a first portion (34) of the accessory (32) proximal the interface (36) and a second support (40) configured to support a second portion (35) of the accessory (32) distal from the interface (36). The second support (40) may be configured to provide a lower resistance to relative displacement between the accessory (32) and structure (42) of the engine (10) than does the first support (34).

Abstract: A method of applying a nanocrystalline metal coating to a titanium or titanium alloy blade of a gas turbine engine is described. The method includes selecting an intermediate bond coat from the group consisting of nickel, nickel alloy, P, B, Tl and combinations thereof, and applying the intermediate bond coat to at least a portion of the blade. A nanocrystalline metal coating having an average grain size of between 10 nm and 500 nm is then applied to the portion of the blade overtop of the intermediate bond coat.

Abstract: The gas turbine engine vane assembly has a vane having an elongated airfoil body extending to a tip and a grommet disposed around the tip. An insert having a closed loop shape with an inner surface matingly shaped to receive the outer surface of the grommet, and an outer surface matingly shaped to be snugly received in the slot. A method of mounting such a vane assembly is also disclosed.

Abstract: A method of applying a nanocrystalline coating to a gas turbine engine component is described. The method comprises the steps of applying an intermediate bond coat to at least a portion of the component, and then applying the nanocrystalline coating to at least the portion of the component overtop of the intermediate bond coat. The component may include, for example, a blade of which a dovetail portion of the blade root is protected by applying the intermediate bond coat and the nanocrystalline coating thereto.

Abstract: A gas turbine engine having a coupling element for coupling a first shaft to a second shaft, the second shaft being substantially axially aligned with the first shaft, the coupling element provided with an exterior surface that engages an opposing interior surface of the first shaft and an interior surface that engages an opposing exterior surface of the second shaft to facilitate torque transfer between the first shaft and the second shaft when rotated together, wherein the coupling element and at least one of the first and second shafts cooperate to define at least one fluid passageway therebetween.

Abstract: The blade dovetails and associated dovetail slots of a gas turbine engine rotor assembly are shaped so that during windmilling the high stress regions of the blade dovetails are shielded from rubbing against the disk and vice versa. Bumper surfaces are provided in low stress regions of the dovetail assembly such that the windmilling contact points between the blade dovetails and the disk are in non-critical areas of the dovetail assembly.

Abstract: A system for cooling a generator mounted in the tail-cone of an engine. The system comprises a fairing, which receives through an inlet thereof air from a bypass duct and directs the bypass air towards a cavity of the tail-cone for cooling the generator. The bypass air is then expelled through an outlet of a support strut positioned in fluid communication with the tail-cone cavity. The fairing inlet and the strut outlet are both positioned in a plane substantially perpendicular to a longitudinal plane of the engine. In this manner, circulation of the bypass air through the fairing, the tail-cone cavity, and the strut may be achieved. The bypass air directed through the fairing further enables cooling of service lines accommodated in the fairing. A lobe mixer is further used to direct the fairing and shield the latter from core exhaust.

Abstract: Systems and methods for pressurization of a generator in a gas turbine engine. The system may include a fluid valve for permitting or inhibiting airflow into a housing of the generator. The fluid valve may be in fluid communication with an air source within the engine, and may be configured to permit airflow into the housing of the generator when pressure within the housing is below a preset pressure threshold or range.

Abstract: A fan case for a gas turbine engine is provided to prevent water from pooling and freezing inside the fan case when the gas turbine is not in operation, and potentially prevent the engine from starting and/or cause engine damage. The fan case is therefore adapted to provide a drainage system allowing water to freely escape the fan case without compromising the structural integrity of the fan case. The fan case comprises: a hollow body; an abradable liner disposed inside the hollow body; a flange on the hollow body defining a surface for mating to a forward part of the engine; and, a first radial slot extending across the mating surface of the hollow body. The abradable liner has an inside surface for circumscribing the fan blades wherein the first radial slot is in a free-draining relation with the inside surface of the abradable liner.

Abstract: A nose cone for a turbofan gas turbine engine includes a central tip, an outer perimeter and a substantially conical outer wall extending therebetween which encloses a cavity therewithin. The outer wall includes an inner substrate layer facing the cavity and an outer layer which overlies and at least partially encloses the inner substrate layer. The outer layer is composed entirely of a nanocrystalline metal forming an outer surface of the nose cone.

Abstract: Devices and methods for supporting an accessory (32) in a gas turbine engine (10) are disclosed. The accessory (32) may have an interface (36) for coupling to a shaft (24) of the gas turbine engine (10). The device may comprise a first support (38) configured to support a first portion (34) of the accessory (32) proximal the interface (36) and a second support (40) configured to support a second portion (35) of the accessory (32) distal from the interface (36). The second support (40) may be configured to provide a lower resistance to relative displacement between the accessory (32) and structure (42) of the engine (10) than does the first support (34).

Abstract: A fan rotor has a fan web and a plurality of circumferentially spaced-apart fan blades extending radially outwardly from an outer rim of the fan web. The outer rim is integrally connected to an inner rim through an axially facing web section. The web section has an inward concavature and extends aft of the center of gravity of the fan blades to shift the center of gravity of the hub rearwards while maintaining airfoil stress below critical levels. The rim section may have an inwardly projecting annular channel formed in a leading edge thereof and tuned to the 2M3ND mode of the fan hub.