A method for operating a hybrid-electric propulsion system of an aircraft, the hybrid-electric propulsion system comprising: a first propulsor assembly, the first propulsor assembly comprising: a turbomachine; a first propulsor coupled to the turbomachine; and an electric machine coupled to the turbomachine; a second propulsor assembly, the second propulsor assembly being an electric propulsor assembly; and an electric energy storage unit electrically coupled to the electric machine and the second propulsor assembly, the method comprising: 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 on the received information indicative of the operability parameter of the turbomachine; operating the hybrid electric propulsion system in an electric generation mode to generate electric power to charge the electric energy storage unit with the electric machine in response to determining the turbomachine is operating within the predetermined operability range; and providing electrical power from at least one of the electric machine and the electric energy storage unit to the second propulsor assembly to at least partially drive the second propulsor assembly; wherein a first amount of electrical power is provided from the electric machine to the electric energy storage unit when the operability parameter of the turbomachine is below an upper threshold of the predetermined operability range by a first quantity and a second amount of electrical power is provided from the electric machine to the electric energy storage unit when the operability parameter of the turbomachine is below the upper threshold of the predetermined operability range by a second quantity, the first amount being greater than the second amount and the first quantity being greater than the second quantity. a first propulsor assembly, the first propulsor assembly comprising: a turbomachine; a first propulsor coupled to the turbomachine; and an electric machine coupled to the turbomachine; a turbomachine; a first propulsor coupled to the turbomachine; and an electric machine coupled to the turbomachine; a second propulsor assembly, the second propulsor assembly being an electric propulsor assembly; and an electric energy storage unit electrically coupled to the electric machine and the second propulsor assembly, the method comprising: 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 on the received information indicative of the operability parameter of the turbomachine; operating the hybrid electric propulsion system in an electric generation mode to generate electric power to charge the electric energy storage unit with the electric machine in response to determining the turbomachine is operating within the predetermined operability range; and providing electrical power from at least one of the electric machine and the electric energy storage unit to the second propulsor assembly to at least partially drive the second propulsor assembly; wherein a first amount of electrical power is provided from the electric machine to the electric energy storage unit when the operability parameter of the turbomachine is below an upper threshold of the predetermined operability range by a first quantity and a second amount of electrical power is provided from the electric machine to the electric energy storage unit when the operability parameter of the turbomachine is below the upper threshold of the predetermined operability range by a second quantity, the first amount being greater than the second amount and the first quantity being greater than the second quantity. 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 on the received information indicative of the operability parameter of the turbomachine; operating the hybrid electric propulsion system in an electric generation mode to generate electric power to charge the electric energy storage unit with the electric machine in response to determining the turbomachine is operating within the predetermined operability range; and providing electrical power from at least one of the electric machine and the electric energy storage unit to the second propulsor assembly to at least partially drive the second propulsor assembly; wherein a first amount of electrical power is provided from the electric machine to the electric energy storage unit when the operability parameter of the turbomachine is below an upper threshold of the predetermined operability range by a first quantity and a second amount of electrical power is provided from the electric machine to the electric energy storage unit when the operability parameter of the turbomachine is below the upper threshold of the predetermined operability range by a second quantity, the first amount being greater than the second amount and the first quantity being greater than the second quantity.