Abstract: A method is provided for operating a hybrid-electric propulsion system of an aircraft. The hybrid-electric propulsion system includes a gas turbine engine having a high pressure system, a low pressure system, an electric machine coupled to at least one of the high pressure system or low pressure system, and an energy storage unit. The method includes operating the electric machine as an electric generator to charge the energy storage unit during a flight operation of the aircraft; switching the gas turbine engine to an electric operating mode during or after a landing operation of the aircraft; driving a system of the gas turbine engine using power from the energy storage unit while in the electric operating mode to provide or assist with providing ground operations the aircraft.

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: A propulsion system, the propulsion system comprising a rotating element, a stationary element, and an inlet between the rotating element and the stationary element, wherein the inlet passes radially inward of the stationary element; wherein the inlet passes radially inward of the stationary element; wherein the inlet leads to an inlet duct containing a ducted fan having an axis of rotation and a plurality of blades; and wherein the inlet duct divides into a first duct and a second duct, separate from the first duct. A method of operating a propulsion system, comprising the steps of: operating a first rotating fan assembly to produce a first stream of air; directing a portion of the first stream of air into a second ducted rotating fan assembly; operating the second ducted rotating fan assembly to produce a second stream of air; dividing the second stream of air into a core stream and a fan stream; and directing the core stream into a gas turbine engine core.