Abstract: A method of operating a hybrid-electric propulsion system for an aircraft includes determining a flight phase parameter for the aircraft is equal to a first value, and operating the hybrid-electric propulsion system in an electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the first value. The method also includes determining the flight phase parameter for the aircraft is equal to a second value different from the first value, and operating the hybrid-electric propulsion system in an electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the second value.

Abstract: A hybrid-electric propulsion system includes a turbomachine, a propulsor coupled to the turbomachine, and an electrical system, the electrical system including an electric machine coupled to the turbomachine. A method for operating a hybrid-electric propulsion system includes operating, by one or more computing devices, the turbomachine in an idle operating condition; receiving, by the one or more computing devices, a command to accelerate the turbomachine while operating the turbomachine in the idle operating condition; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine and increase an acceleration of the turbomachine in response to the received command to accelerate the turbomachine.

Abstract: Systems and methods for estimating engine and electrical machine health are provided. The systems and methods therefore include features that provide for improved health estimates of one or more engines and/or electrical machines of one or more engines having an electrical machine embedded therein or coupled thereto. In particular, the systems and methods therefore include features for utilizing sensed or measured operating parameters of the electrical machines and/or operating parameters of the prime mover to estimate the health of the prime mover and/or the electrical machines embedded therein or coupled thereto.

Abstract: A hybrid-electric propulsion system includes a turbomachine, a propulsor coupled to the turbomachine, and an electrical system, the electrical system including an electric machine coupled to the turbomachine. A method for operating a hybrid-electric propulsion system includes operating, by one or more computing devices, the turbomachine in an idle operating condition; receiving, by the one or more computing devices, a command to accelerate the turbomachine while operating the turbomachine in the idle operating condition; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine and increase an acceleration of the turbomachine in response to the received command to accelerate the turbomachine.

Abstract: A hybrid-electric propulsion system includes a turbomachine and an electrical system, the electrical system including an electric machine coupled to the turbomachine. A method for operating the propulsion system includes receiving, by one or more computing devices, a command to accelerate the turbomachine to provide a desired thrust output; receiving, by the one or more computing devices, data indicative of a temperature parameter approaching or exceeding an upper threshold; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine to provide, or assist with providing, the desired thrust output in response to receiving the command to accelerate the turbomachine and receiving the data indicative of the temperature parameter approaching or exceeding the upper threshold.

Abstract: A hybrid-electric propulsion system includes a propulsor, a turbomachine, and an electrical system, the electrical system including an electric machine coupled to the turbomachine. A method for operating the propulsion system includes operating, by one or more computing devices, the turbomachine such that the turbomachine rotates the propulsor; receiving, by the one or more computing devices, a command to accelerate the turbomachine while operating the turbomachine; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine, the propulsor, or both in response to the received command to accelerate the turbomachine.

Abstract: A hybrid-electric propulsion system includes a propulsor, a turbomachine, and an electrical system having an electric machine coupled to the turbomachine. A method for operating the propulsion system includes operating, by one or more computing devices, the turbomachine to rotate the propulsor and generate thrust for the aircraft; receiving, by the one or more computing devices, data indicative of an un-commanded loss of the thrust generated from the turbomachine rotating the propulsor; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine, the propulsor, or both in response to receiving the data indicative of the un-commanded loss of thrust.

Abstract: A hybrid-electric propulsion system includes a propulsor, a turbomachine, and an electrical system, the electrical system including an electric machine coupled to the turbomachine. A method for operating the propulsion system includes operating, by one or more computing devices, the turbomachine in a steady-state flight operating condition, the turbomachine rotating the propulsor when operated in the steady-state flight operating condition; receiving, by the one or more computing devices, a command to accelerate the turbomachine while operating the turbomachine in the steady-state flight operating condition; and providing, by the one or more computing devices, electrical power to the electric machine to add power to the turbomachine, the propulsor, or both in response to the received command to accelerate the turbomachine.

Abstract: A method of operating a hybrid-electric propulsion system for an aircraft includes determining a flight phase parameter for the aircraft is equal to a first value, and operating the hybrid-electric propulsion system in an electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the first value. The method also includes determining the flight phase parameter for the aircraft is equal to a second value different from the first value, and operating the hybrid-electric propulsion system in an electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the second value.

Abstract: Systems and methods for estimating engine and electrical machine health are provided. The systems and methods therefore include features that provide for improved health estimates of one or more engines and/or electrical machines of one or more engines having an electrical machine embedded therein or coupled thereto. In particular, the systems and methods therefore include features for utilizing sensed or measured operating parameters of the electrical machines and/or operating parameters of the prime mover to estimate the health of the prime mover and/or the electrical machines embedded therein or coupled thereto.

Abstract: A hybrid-electric propulsion system includes an electric machine coupled to a rotating system of the turbomachine and an electric energy storage unit, the electric machine electrically coupled to an electric power source. A method for operating the turbomachine of a hybrid-electric propulsion system includes providing electrical power from the electric machine to the electric energy storage unit during a flight operation mode of the turbomachine, the turbomachine rotating the electric machine to generate electrical power during the flight operating mode; determining the turbomachine is in a post flight operation mode or in a pre-flight operation mode; and providing electrical power from the electric power source to the electric machine such that the electric machine rotates the rotating system of the turbomachine to prevent or correct a bowed rotor condition.

Abstract: A hybrid-electric propulsion system includes a turbomachine and an electric machine coupled to the turbomachine. A method for operating the hybrid-electric propulsion system includes receiving information indicative of an operability parameter of the turbomachine; determining the turbomachine is operating within a predetermined operability range based at least in part of the received information indicative of the operability parameter of the turbomachine; and operating the hybrid electric propulsion system in an electric generation mode to generate electric power with the electric machine in response to determining the turbomachine is operating within the predetermined operability range.

Abstract: A hybrid-electric propulsion system includes a propulsor, a turbomachine, and an electrical system. The electrical system includes a first electric machine coupled to the turbomachine and an electric energy storage unit. A method for operating the propulsion system includes operating the hybrid electric propulsion system in a flight operation mode. The method also includes operating the hybrid electric propulsion system in a maintenance operation mode, wherein operating the hybrid electric propulsion system in the maintenance operation mode includes providing electrical power from an electrical power source to the first electric machine such that the first electric machine rotates a compressor and a turbine of the turbomachine during a borescope inspection of the turbomachine.

Abstract: A computer-implemented method of assessing a health of a gas turbine engine of a hybrid-electric propulsion system for an aircraft includes receiving, by one or more computing devices, data indicative of an amount of electrical power provided to, or extracted from, an electric machine. The method also includes receiving, by the one or more computing devices, data indicative of an operating parameter of the hybrid-electric propulsion system. The method also includes assessing, by the one or more computing devices, a health of the gas turbine engine based at least in part on the received data indicative of the amount of electrical power provided to, or extracted from, the electric machine and the received data indicative of the operating parameter of the hybrid electric propulsion system. The method also includes providing, by the one or more computing devices, information to a user indicative of the health of the gas turbine engine.

Abstract: A hybrid-electric propulsion system for an aircraft includes a turbomachine, the turbomachine including a first spool and a second spool. A method for operating the hybrid electric propulsion system includes operating, by one or more computing devices, the turbomachine such that the first spool mechanically drives a prime propulsor of the hybrid-electric propulsion system; and modifying, by the one or more computing devices, a speed relationship parameter defined between the first spool and second spool by providing electrical power to, or drawing electrical power from, an electric machine mechanically coupled to the first spool, the second spool, or both.

Abstract: A hybrid-electric propulsion system for an aircraft includes a propulsor and a turbomachine. The turbomachine includes a high pressure turbine drivingly coupled to a high pressure compressor through a high pressure spool. The hybrid electric propulsion system further includes an electrical system including a first electric machine, a second electric machine, and an electric energy storage unit electrically connectable to the first and second electric machines. The first electric machine is coupled to the high pressure spool of the turbomachine and the second electric machine is coupled to the propulsor for driving the propulsor to provide a propulsive benefit for the aircraft. The hybrid electric propulsion system also includes a controller configured to provide electrical power from an electric power source to the first electric machine to drive the first electric machine to start, or assist with starting, the turbomachine.

Abstract: A propulsion system for an includes a combustion engine, a propulsor, and an electric machine configured to either be driven by the combustion engine or configured to drive the propulsor. The electric machine defines an axis. The electric machine includes a rotor extending along and rotatable about the axis, and a stator having a plurality of winding assemblies, the plurality of winding assemblies spaced along the axis of the electric machine, each winding assembly operable with the rotor independently of an adjacent winding assembly during operation of the electric machine.

Abstract: Methods and apparatus for detecting a sensor angle error in a system in which a measured quantity is determined on the basis of a phase of a signal. A signal derived from the measurement of multiple sensors is ascribed to a vector in a two-dimensional space, and a norm is calculated characterizing that vector. A value is calculated characterizing variation of that norm over a specified period of time and that value is compared with a threshold in order to identify a sensor fault.