Abstract: Auxiliary power systems, aircraft including the same, and related methods are disclosed herein. In one embodiment, the aircraft includes an airframe and an auxiliary power system that includes an auxiliary power unit (APU), an APU controller, and a bleed air temperature (BAT) sensor. The APU defines a bleed air outlet and is configured to regulate a BAT of a bleed air flow generated by the auxiliary power unit. The BAT sensor is positioned at a remote BAT location that is outside the bleed air outlet of the APU. In another embodiment, the auxiliary power system includes an APU configured to generate a bleed air flow, an APU controller configured to receive and transmit signals, and a BAT sensor suite configured to measure the BAT of the bleed air flow and to generate a BAT signal that is based, at least in part, on the BAT.

Abstract: Gas turbine engine starter systems and associated methods. A gas turbine engine starter system includes an engine starter with a starter torque output configured to convey a starter torque to a gas turbine engine. An engine startup process includes a spool-up time interval in which the engine rotational speed increases to a speed within an engine starting speed envelope. During at least a portion of the spool-up time interval, the starter torque is less than a speed-dependent maximum torque value of the starter torque that the engine starter is configured to produce. A method of operating a gas turbine engine starter system includes operating an engine starter to accelerate the gas turbine engine such that the starter torque is less than a speed-dependent maximum torque value of the starter torque that the engine starter is configured to produce during at least a portion of a spool-up time interval.

Abstract: Auxiliary power systems, aircraft including the same, and related methods are disclosed herein. In one embodiment, the aircraft includes an airframe and an auxiliary power system that includes an auxiliary power unit (APU), an APU controller, and a bleed air temperature (BAT) sensor. The APU defines a bleed air outlet and is configured to regulate a BAT of a bleed air flow generated by the auxiliary power unit. The BAT sensor is positioned at a remote BAT location that is outside the bleed air outlet of the APU. In another embodiment, the auxiliary power system includes an APU configured to generate a bleed air flow, an APU controller configured to receive and transmit signals, and a BAT sensor suite configured to measure the BAT of the bleed air flow and to generate a BAT signal that is based, at least in part, on the BAT.

Abstract: Auxiliary power systems, aircraft including the same, and related methods. An auxiliary power system comprises an auxiliary power unit (APU) controller and an APU with an air intake, a powerhead, and a load compressor stage. The load compressor stage includes a flow regulator assembly, a load compressor, and a bleed air temperature (BAT) sensor for generating a BAT signal. The APU controller regulates a flow rate of a load compressor airflow through the load compressor based on the BAT signal. A method of utilizing an auxiliary power system includes compressing a load compressor airflow to generate a bleed air flow, measuring the BAT with a BAT sensor, generating a BAT signal based on the BAT, transmitting the BAT signal to an APU controller, generating a flow regulator command with the APU controller, transmitting the flow regulator command to a flow regulator assembly, and controlling a flow regulator assembly.

Abstract: Auxiliary power systems, aircraft including the same, and related methods. An auxiliary power system comprises an auxiliary power unit (APU) controller and an APU with an air intake, a powerhead, and a load compressor stage. The load compressor stage includes a flow regulator assembly, a load compressor, and a bleed air temperature (BAT) sensor for generating a BAT signal. The APU controller regulates a flow rate of a load compressor airflow through the load compressor based on the BAT signal. A method of utilizing an auxiliary power system includes compressing a load compressor airflow to generate a bleed air flow, measuring the BAT with a BAT sensor, generating a BAT signal based on the BAT, transmitting the BAT signal to an APU controller, generating a flow regulator command with the APU controller, transmitting the flow regulator command to a flow regulator assembly, and controlling a flow regulator assembly.