Abstract: A method for operating a hybrid-electric propulsion system of an aircraft, the hybrid-electric propulsion system comprising a gas turbine engine having a compressor and an electric machine coupled to the compressor, the method comprising: sensing data indicative of a pressure within the compressor of the gas turbine engine; determining conditions within the compressor are within a threshold of a stall limit for the compressor based at least in part on the sensed data indicative of the pressure within the compressor of the gas turbine engine; and modifying a torque of the compressor using the electric machine in response to determining the conditions within the compressor are within the threshold of the stall limit for the compressor to reduce a risk of compressor stall.

Abstract: A method for operating a hybrid-electric propulsion system of an aircraft is provided. The hybrid-electric propulsion system includes a gas turbine engine having a high pressure system, a low pressure system, and an electric machine coupled to one of the high pressure system or low pressure system. The method includes receiving data indicative of an actual or anticipated in-flight shutdown of the gas turbine engine; and adding power to the gas turbine engine through the electric machine in response to receiving data indicative of the actual or anticipated in-flight shutdown of the gas turbine engine.

Abstract: A method for operating a hybrid-electric gas turbine engine is provided. The method includes: receiving data indicative of an actual rotational speed of a shaft; calculating an error between the actual rotational speed of the shaft and a commanded rotational speed of the shaft; providing the calculated error to a fuel flow control circuit operable with a fuel delivery system of the hybrid-electric propulsion engine; providing the calculated error to an electric machine control circuit operable with an electric machine of the hybrid-electric propulsion engine, the electric machine drivingly coupled to the shaft; and modifying a torque on the shaft from the electric machine with the electric machine control circuit based on the calculated error.

Abstract: A method is provided for operating a hybrid-electric propulsion system having a first engine, a second engine, a first electric machine coupled to the first engine, and a second electric machine coupled to one of the first engine or the second engine. The method includes: receiving data indicative of a first engine operating parameter, a second engine operating parameter, or both; determining a first engine operating parameter margin, a second parameter operating margin, or both; determining a load share for the first engine, the second engine, or both, or between the first engine and the second engine based on the first engine operating parameter margin, the second engine operating parameter margin, or both; and transferring a first amount of power to or from the first electric machine and a second amount of power to or from the second electric machine in response to the determined load share.

Abstract: An engine system is provided for an aircraft having an engine and an engine controller. The engine system includes: an electric machine configured to be in electrical communication with the engine controller for powering the engine controller; and a fuel oxygen reduction unit defining a liquid fuel flowpath and a stripping gas flowpath and configured to transfer an oxygen content of a fuel flow through the liquid fuel flowpath to a stripping gas flow through the stripping gas flowpath, the fuel oxygen reduction unit also in electrical communication with the electric machine such that the electric machine powers at least in part the fuel oxygen reduction unit.

Abstract: A computing system for an unducted rotor engine with a variable pitch vane assembly in aerodynamic relationship with an unducted rotor assembly, including a sensor-based controller configured to execute a first set of operations and a model-based controller configured to execute a second set of operations. The first set of operations includes obtaining a first signal corresponding to a commanded low spool speed; obtaining a second signal indicative of a pitch angle corresponding to thrust output from the unducted rotor assembly and variable pitch vane assembly; generating a pitch feedback signal corresponding to a commanded adjustment to the pitch angle based at least on one or both of a variable blade pitch angle or a variable vane pitch angle. The second set of operations include obtaining a desired thrust output via a throttle input; determining, at least via a power management block, a commanded thrust output signal; receiving the commanded thrust output signal; and generating an output signal.

Abstract: A propulsion system is provided, the propulsion system including a variable pitch rotor assembly including a plurality of blades coupled to a disk. The plurality of blades includes a first blade configured to articulate a first blade pitch separately from a second blade configured to articulate a second blade pitch. A vane assembly is positioned in aerodynamic relationship with the variable pitch rotor assembly. A core engine including a high speed spool and a low speed spool, wherein the low speed spool is operably coupled to the rotor assembly. One or more controllers is configured to execute operations. The operations include articulating the first blade of the rotor assembly, wherein articulating the first blade alters the first blade pitch, and articulating the second blade of the rotor assembly, wherein articulating the second blade alters the second blade pitch.

Abstract: An aircraft can comprise an engine, an environmental control system, an engine controller, and a plurality of sensors detecting engine or aircraft parameters. Engine or aircraft operation can be updated in real time based on input from the sensors, including airflow management or operation parameters.