An air turbine starter includes a support structure and a turbine having a shaft and a rotor that extends away from the shaft in a radial direction. The air turbine starter also includes a mount structure that supports the turbine for rotation relative to the support structure. The mount structure is configured to transfer a force from the turbine to the support structure. The mount structure includes a deformable member that is configured to deform when the force exceeds a predetermined threshold.

An air turbine starter includes a support structure and a turbine having a shaft and a rotor that extends away from the shaft in a radial direction. The air turbine starter also includes a mount structure that supports the turbine for rotation relative to the support structure. The mount structure is configured to transfer a force from the turbine to the support structure. The mount structure includes a deformable member that is configured to deform when the force exceeds a predetermined threshold.

An aircraft system includes a component configured to operate with a minimum power demand. The aircraft system also includes an auxiliary power unit including an engine. The auxiliary power unit is configured to power the component and to operate the engine in a plurality of operating modes including a power mode and a standby mode. The auxiliary power unit generates a first power output at least equal to the minimum power demand during the power mode. The auxiliary power unit generates a second power output less than the minimum power demand during the standby mode.

An aircraft system includes a component configured to operate with a minimum power demand. The aircraft system also includes an auxiliary power unit including an engine. The auxiliary power unit is configured to power the component and to operate the engine in a plurality of operating modes including a power mode and a standby mode. The auxiliary power unit generates a first power output at least equal to the minimum power demand during the power mode. The auxiliary power unit generates a second power output less than the minimum power demand during the standby mode.

A method of operating a turbine engine that includes shutting down the turbine engine such that a rotational speed of the turbine engine decreases, and actuating a starter motor of the turbine engine at one of as the rotational speed of the turbine engine decreases or at a preset time after the turbine engine receives a full stop command such that residual heat is exhausted from the turbine engine.

A method of operating a turbine engine that includes shutting down the turbine engine such that a rotational speed of the turbine engine decreases, and actuating a starter motor of the turbine engine at one of as the rotational speed of the turbine engine decreases or at a preset time after the turbine engine receives a full stop command such that residual heat is exhausted from the turbine engine.

A method and decoupler for disengaging an output shaft from an engine in a back drive event with a backdrive decoupler. The backdrive decoupler includes a threaded shaft and a retention mechanism selectively coupling the output shaft to the threaded shaft. In a backdrive event, the decoupler decouples the output shaft from a drive shaft.

A method and decoupler for disengaging an output shaft from an engine in a back drive event with a backdrive decoupler. The backdrive decoupler includes a threaded shaft and a retention mechanism selectively coupling the output shaft to the threaded shaft. In a backdrive event, the decoupler decouples the output shaft from a drive shaft.

An air turbine start system is provided that includes an air turbine starter, a starter air valve, a turbine speed sensor, and a circuit. The starter air valve is movable between an open position, in which the pressurized air may flow into the air turbine starter, and a closed position, in which pressurized air does not flow into the air turbine starter. The turbine speed sensor is coupled to the air turbine starter, and is configured to sense the rotational speed of the turbine and supply a rotational speed signal representative thereof. The circuit is coupled to receive the rotational speed signal and is configured, upon receipt thereof, to determine whether the starter air valve is in the closed position or an open position.

An air turbine start system is provided that includes an air turbine starter, a starter air valve, a turbine speed sensor, and a circuit. The starter air valve is movable between an open position, in which the pressurized air may flow into the air turbine starter, and a closed position, in which pressurized air does not flow into the air turbine starter. The turbine speed sensor is coupled to the air turbine starter, and is configured to sense the rotational speed of the turbine and supply a rotational speed signal representative thereof. The circuit is coupled to receive the rotational speed signal and is configured, upon receipt thereof, to determine whether the starter air valve is in the closed position or an open position.