A hybrid propulsion installation for an aircraft, including an internal combustion engine having at least one combustion chamber; at least one electricity generator; an electrical propulsion system; electromechanical protection mechanism arranged between the or each electricity generator and the electrical propulsion system; wherein the installation also includes: an electronic computer configured to: receive at least one piece of information on a position of the electromechanical protection mechanism; receive at least one piece of information on a speed of rotation of a shaft of the internal combustion engine; and control the flow of fuel supplying the combustion chamber depending on the information received.

A hybrid propulsion installation for an aircraft, including an internal combustion engine having at least one combustion chamber; at least one electricity generator; an electrical propulsion system; electromechanical protection mechanism arranged between the or each electricity generator and the electrical propulsion system; wherein the installation also includes: an electronic computer configured to: receive at least one piece of information on a position of the electromechanical protection mechanism; receive at least one piece of information on a speed of rotation of a shaft of the internal combustion engine; and control the flow of fuel supplying the combustion chamber depending on the information received.

A propulsion assembly includes a first torque source coupled with a first shaft and a second torque source coupled with a second shaft. A coupler selectively couples the first and second torque sources. When the first and second torque sources are coupled via the coupler, in response to a command to decouple the first torque source, an unloading operation is performed to decrease the torque output provided by the first torque source to a threshold, and when reached, the first shaft is decoupled from the coupler. When the first torque source is coupled with the coupler but the second torque source is not, in response to a command to couple the second torque source, a speed matching operation is performed to increase the speed of the second shaft to match a speed of the first shaft, and when the speeds are matched, the second shaft is coupled to the coupler.

A propulsion assembly includes a first torque source coupled with a first shaft and a second torque source coupled with a second shaft. A coupler selectively couples the first and second torque sources. When the first and second torque sources are coupled via the coupler, in response to a command to decouple the first torque source, an unloading operation is performed to decrease the torque output provided by the first torque source to a threshold, and when reached, the first shaft is decoupled from the coupler. When the first torque source is coupled with the coupler but the second torque source is not, in response to a command to couple the second torque source, a speed matching operation is performed to increase the speed of the second shaft to match a speed of the first shaft, and when the speeds are matched, the second shaft is coupled to the coupler.

A propulsion system is provided for an aircraft. This propulsion system includes a propulsor rotor, a drivetrain, a first power unit and a second power unit. The drivetrain is coupled to the propulsor rotor. The first power unit includes a first overrunning clutch and a first electric motor. The first overrunning clutch is configured to selectively couple the first electric motor to the drivetrain. The first electric motor is configured to drive rotation of the propulsor rotor through the first overrunning clutch and the drivetrain. The second power unit includes a second overrunning clutch and a second electric motor. The second overrunning clutch is configured to selectively couple the second electric motor to the drivetrain. The second electric motor is configured to drive the rotation of the propulsor rotor through the second overrunning clutch and the drivetrain.

A propulsion system for an aircraft is provided that includes an electric generator, a compressor, an internal combustion (IC) engine, a turbine, an electric power storage unit, and an electric motor. The compressor is configured to selectively produce a flow of compressor air at an air pressure greater than an ambient air pressure. The IC engine is configured to selectively intake compressor air during operation and produce an exhaust gas flow during operation. The turbine, powered by exhaust gas flow, is in communication with and configured to power the compressor and the electric generator. The electric power storage unit is in communication with the electric generator. The electric motor is in communication with the IC engine. The electric motor is powered by the electrical power produced by the electric generator, and the electric motor is configured to selectively provide motive force to the IC engine.

A method for controlling a thermal and electrical power plant for setting in motion at least one rotary member of a rotorcraft, the power plant comprising at least one heat engine and an electrical system provided with at least one electric machine. The method comprises: selecting, with a selector, an operating mode chosen from several operating modes; determining a density altitude and comparing, with a controller, the current density altitude and a threshold density altitude; and controlling, with the controller, the at least one electric machine depending on at least the chosen operating mode as well as the comparison and a necessary power to be supplied to the power transmission system.

A method for controlling a thermal and electrical power plant for setting in motion at least one rotary member of a rotorcraft, the power plant comprising at least one heat engine and an electrical system provided with at least one electric machine. The method comprises: selecting, with a selector, an operating mode chosen from several operating modes; determining a density altitude and comparing, with a controller, the current density altitude and a threshold density altitude; and controlling, with the controller, the at least one electric machine depending on at least the chosen operating mode as well as the comparison and a necessary power to be supplied to the power transmission system.

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.

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.