A disk assembly may include: a first disk engaged with a compressor section of a gas turbine; a second disk engaged with a turbine section of the gas turbine; and a third disk disposed between the first and second disks, and transferring torque applied to the second disk to the first disk. The third disk has a plurality of legs formed on an inner circumferential surface thereof, the plurality of legs being in contact with an outer circumferential surface of a tie bolt of the gas turbine.

An air starter for an engine, such as a turbine engine, that includes a turbine for rotatably extracting mechanical power from a flow of fluid. The turbine includes a drive shaft that can be coupled to an output shaft to provide a rotational output. The interface between the drive shaft and the output shaft can be offset and include piloted portions.

The invention relates to an assembly for a turbine engine, comprising a radially inner shaft (3) and a radially outer shaft (7), said shafts (7, 8) being coaxial and extending along an axis (X), means (11, 15) for coupling said inner and outer shafts (7, 8) in rotation, means (22) for axially holding the inner shaft (8) relative to the outer shaft (7), means for centring the inner shaft (8) relative to the outer shaft (7), characterised in that the centring means comprise a shim (14) for radial centring and for axial positioning, this shim being frustoconical and interposed between a frustoconical centring surface (13) of the inner shaft (8) and a corresponding frustoconical centring surface (10) of the outer shaft (7).

An oil system for a gas turbine engine includes an oil pump driven by a gear train having a main input drive gear rotating when a propulsor rotor rotates. The gear train includes two sets of gears joined by two connection shafts each having a clutch. The first set of the gears include a forward input gear and a reverse input gear each driven by the main input drive gear. The forward and the reverse input gears drive a pinion gear in the second set of gears through a clutch. Each clutch transmits rotation driven in a same driving direction and slips in an alternate driving direction. The first set of the gears has an even number of the gears, and the second set of the gears has an odd number of the gears.

A coupling has: a first coupler rotatable about an axis and defining first connections distributed about the axis; a second coupler defining second connections distributed about the axis, the second connections offset from the first connections; and segments distributed about the axis and extending radially from the first connections to the second connections, a segment of the segments having a first end engaging a first connection of the first connections and a second end engaging a second connection of the second connections, the first end circumferentially offset from the second end, a face of the segment abutting against a face of the first coupler when the segment is inserted into the first connection in a first orientation such that a penetration depth of the segment into the first connection in the first orientation is less than the penetration depth in a second orientation opposite the first orientation.

An aircraft power plant comprising: a high-pressure spool including a high-pressure compressor, a high-pressure turbine, and a high-pressure shaft drivingly engaging the high-pressure turbine to the high-pressure compressor; a low-pressure spool including a low-pressure compressor, a low-pressure turbine, and a low-pressure shaft drivingly engaging the low-pressure turbine to the low-pressure compressor; an electrical machine operable as a generator; and a transmission having a first input drivingly engaged by the high-pressure shaft, a second input drivingly engaged by the low-pressure shaft, and an output drivingly engaging the electrical machine, the transmission having a coupling system selectively interconnecting the output with one of: the first input, with the second input disconnected from the output; the second input, with the first input disconnected from the output; and both of the first input and the second input.

A turbofan engine includes a fan that delivers air into a bypass duct and into a core engine. A fan drive gear system includes a gear carrier and at least one ring gear. The at least one ring gear is coupled to an engine case of the turbofan engine with a compliant flexure. A fan shaft couples the gear carrier in the fan drive gear system to the fan. A first bearing is forward of the fan drive gear system and supports the fan drive gear system. A second bearing is aft of the fan drive gear system and supports the fan drive gear system.

An assembly is provided for a turbine engine. This turbine engine assembly includes a turbine engine shaft, a gearbox and a coupler. The turbine engine shaft is configured to rotate about a rotational axis. The gearbox includes a gear configured to rotate about the rotational axis. The coupler is coupled to the turbine engine shaft by a coupler-shaft connection. The coupler-shaft connection is configured as or otherwise includes a crowned spline connection. The coupler is coupled to the gear by a coupler-gear connection. The coupler-gear connection is configured as or otherwise includes a crowned spline connection.

An air starter for an engine, such as a turbine engine, that includes a turbine for rotatably extracting mechanical power from a flow of fluid. The turbine includes a drive shaft that can be coupled to an output shaft to provide a rotational output. The interface between the drive shaft and the output shaft can be offset.

Systems and methods for preventing rotation of an ESP motor when the motor is not powered on, thereby preventing the motor from acting as a generator when fluid flowing through the pump section of the ESP applies a torque to the motor. In one embodiment, an ESP has a motor section, a pump section. The ESP may include a directional coupling that allows unidirectional rotation between the motor shaft and a pump shaft of the pump section, and a directional lock that allows unidirectional rotation between the motor shaft and a housing of the motor section. The directional coupling and directional lock allow the pump shaft to freewheel in the forward direction without causing the motor shaft to rotate, and prevent the pump shaft and motor from rotating in the reverse direction.