Abstract: A gas turbine engine includes a first spool and a second spool. The first spool includes a compressor stage, a first turbine stage, and a first shaft configured to transmit rotational energy between the first turbine stage and the compressor stage. The second spool includes a fan, a second turbine stage, and a second shaft configured to transmit rotational energy between the second turbine stage and the fan.

Abstract: A gas turbine engine includes a first spool and a second spool. The first spool includes a compressor stage, a first turbine stage, and a first shaft configured to transmit rotational energy between the first turbine stage and the compressor stage. The second spool includes a fan, a second turbine stage, and a second shaft configured to transmit rotational energy between the second turbine stage and the fan.

Abstract: A magnetic squeeze film damper system comprises a bearing assembly having an outer race with a first outer surface and a first inner surface and a bearing located along the first inner surface. The system further comprises a squeeze film damper housing having a second outer surface and a second inner surface that is contiguous with the first outer surface. A channel having a forward end and an aft end is defined within the housing along the second inner surface, the channel bordered by the first outer surface. The system further includes a first seal gland located along the forward end of the channel and a second seal gland located along the aft end of the channel. Both seal glands comprise a reservoir for holding a magneto-rheological fluid, the reservoir encased in an elastomer. At least one electromagnet is arranged in close proximity to each of the seal glands.

Abstract: A magnetic squeeze film damper system comprises a bearing assembly having an outer race with a first outer surface and a first inner surface and a bearing located along the first inner surface. The system further comprises a squeeze film damper housing having a second outer surface and a second inner surface that is contiguous with the first outer surface. A channel having a forward end and an aft end is defined within the housing along the second inner surface, the channel bordered by the first outer surface. The system further includes a first seal gland located along the forward end of the channel and a second seal gland located along the aft end of the channel. Both seal glands comprise a reservoir for holding a magneto-rheological fluid, the reservoir encased in an elastomer. At least one electromagnet is arranged in close proximity to each of the seal glands.

Abstract: An expendable bearing and a method for making the same including an inner race defining an inner bearing diameter, an outer race defining an outer bearing diameter, a seal attached to the outer race and positioned adjacent and in contact with the inner race, where the inner race, the outer race, and the seal define a bearing cavity, a plurality of rolling elements positioned adjacent to the inner and outer races in the bearing cavity, a dry film lubricant on a surface of at least one of the inner race, the outer race, or the plurality of rolling elements, and a powder lubricant comprising carbon nanotubes disposed in the bearing cavity.

Abstract: A clutch for use in a gas turbine engine is disclosed herein. The clutch is adapted to selectively transmit rotation from a first shaft of the clutch to a second shaft of the clutch.

Abstract: A bearing assembly includes an outer race, a cage, a plurality of internal rotating members, and an inner race. Lubricant flows through the bearing assembly to withdraw heat generated during operation of the bearing assembly.

Abstract: A magnetic squeeze film damper system comprises a bearing assembly having an outer race with a first outer surface and a first inner surface and a bearing located along the first inner surface. The system further comprises a squeeze film damper housing having a second outer surface and a second inner surface that is contiguous with the first outer surface. A channel having a forward end and an aft end is defined within the housing along the second inner surface, the channel bordered by the first outer surface. The system further includes a first seal gland located along the forward end of the channel and a second seal gland located along the aft end of the channel. Both seal glands comprise a reservoir for holding a magneto-rheological fluid, the reservoir encased in an elastomer. At least one electromagnet is arranged in close proximity to each of the seal glands.

Abstract: An expendable bearing and a method for making the same including an inner race defining an inner bearing diameter, an outer race defining an outer bearing diameter, a seal attached to the outer race and positioned adjacent and in contact with the inner race, where the inner race, the outer race, and the seal define a bearing cavity, a plurality of rolling elements positioned adjacent to the inner and outer races in the bearing cavity, a dry film lubricant on a surface of at least one of the inner race, the outer race, or the plurality of rolling elements, and a powder lubricant comprising carbon nanotubes disposed in the bearing cavity.

Abstract: A clutch for use in a gas turbine engine is disclosed herein. The clutch is adapted to selectively transmit rotation from a first shaft of the clutch to a second shaft of the clutch.

Abstract: According to the present disclosure, a bearing assembly includes an outer race, a cage, a plurality of internal rotating members, and an inner race. Lubricant flows through the bearing assembly to withdraw heat generated during operation of the bearing assembly.

Abstract: A seal assembly for use in a gas turbine engine includes a first component, a second component, and a sealing unit. The first component is spaced apart from the second component to form a gap therebetween. The sealing unit is positioned in the gap between the first and second components to block liquids and/or gasses from traveling through the gap.

Abstract: An aircraft powerplant having a shaft is disclosed in one embodiment in which a squeeze-film damper is used. The squeeze-film damper includes a plurality of sectors having a working fluid. A pressure can be controlled in the working fluid to the sectors to discourage changes in the sectors as a result of vehicle maneuvering. A controller is used to operate upon sensed aircraft motion and regulate pressure in the sectors.

Abstract: A fluid sealing assembly includes a shaft and a seal. The shaft includes a surface portion having a microstructural geometry. The seal has a radially flexible portion disposed in proximity to the surface portion having the microstructural geometry such that when the shaft is rotated a pressure differential is generated at the interface of the seal and the surface portion having the microstructural geometry that pushes or pulls fluid relative to the interface.

Abstract: A gas turbine engine is provided that includes a gearbox operable to selectively couple a relatively high pressure spool shaft to a relatively low pressure spool shaft. In one form the gearbox includes a cone clutch that engages a male member of the cone clutch to a female member of the cone clutch during an engine start of the gas turbine engine. A relatively high pressure of a working fluid can be used to bring the male member and the female member together. A spring can also be used to urge the male member and the female member apart when the working fluid is at a relatively low pressure.

Abstract: A turbine engine is disclosed herein. The turbine engine includes a starter/generator operable to deliver rotational power in a first mode of operation and to generate electrical power in a second mode of operation. The turbine engine also includes an accessory gear box mechanically coupled to the starter/generator. The turbine engine also includes a shaft mechanically coupled to the accessory gear box such that the accessory gear box is operably disposed between the shaft and the starter/generator. The turbine engine also includes a clutch operably disposed between the accessory gear box and the starter generator. The clutch is operable to slip in and out of full engagement in response to a first predetermined level of torque between the starter/generator and the accessory gear box.

Abstract: A seal assembly for use in a gas turbine engine includes a first component, a second component, and a sealing unit. The first component is spaced apart from the second component to form a gap therebetween. The sealing unit is positioned in the gap between the first and second components to block liquids and/or gasses from traveling through the gap.

Abstract: A multi-plate clutch is provided to couple a drive shaft from a gas turbine engine with a driven shaft of a lift fan. When disengaged the plates of the clutch can be physically separated. Plates of one shaft are coupled to the shaft with individual energy members that return the plates to a disengaged position. The plates of the other shaft can be coupled together with a travel member and/or lug key and energy devices between at least some of the plates.

Abstract: A dual clutch arrangement is disclosed herein. The dual clutch arrangement includes a first input rotatable member. The dual clutch arrangement also includes an output rotatable member. The dual clutch arrangement also includes a first clutch coupling the first input rotatable member and the output rotatable member such that the first input rotatable member drives the output rotatable member in rotation. The first clutch is operable to be overrun. The dual clutch arrangement also includes a second input rotatable member. The dual clutch arrangement also includes a second clutch operable to selectively couple the second input rotatable member and the output rotatable member such that the second input rotatable member drives the output rotatable member in rotation. The first clutch is overrun when the second clutch is engaged.

Abstract: A gearing arrangement is disclosed herein. The gearing arrangement includes a shaft operable to rotate about an axis of rotation. The gearing arrangement also includes a first gear fixed for rotation with the shaft and encircling the axis of rotation. The gearing arrangement also includes a plate member positioned radially adjacent to the shaft. The gearing arrangement also includes a second gear operable to mesh with the first gear. The gearing arrangement also includes a layshaft supporting the second gear. The layshaft extends along a central axis between first and second ends. The layshaft is engageable with the plate member in a plurality of different positions to adjustably position the second gear relative to the first gear.