A method includes controlling an electric motor of a hybrid-electric powerplant for an aircraft using an EPC (electric powertrain controller) and controlling a heat engine of the hybrid-electric powerplant using an ECU (engine control unit). The method includes performing at least one of the following to protect the hybrid-electric powerplant: using the ECU to power down the electric motor, and/or using the EPC to power down the heat engine.

A hybrid electric propulsion (HEP) system can include a heat engine torque sensor connected between a heat engine and a combining gear box to sense a heat motor input torque input to the combining gear box, an electric motor torque sensor connected between an electric motor and the combining gear box to sense an electric motor input torque input to the combining gear box, and a combining gear box torque sensor connected to an output of the combining gearbox. The system can include a HEP controller operatively connected to each of the heat engine torque sensor, the electric motor torque sensor, and the combining gear box torque sensor to receive one or more torque signals therefrom. The controller can be configured to output one or more output signals as a function of the signals from each of the heat engine torque sensor, the electric motor torque sensor, and the combining gear box torque sensor.

A VTOL aircraft includes a plurality of lift propellers configured to rotated by lift motors to provide vertical thrust during takeoff, landing and hovering operations. The lift propellers are configured to generate a cooling airflow to cool the lift motors during use. During a cruise operation when the VTOL aircraft is in forward motion, the lift propellers may be stowed in a stationary position. Therefore, the cooling airflow may be reduced or eliminated when it is not needed.

A disclosed gas turbine engine includes a first electric motor assembly that provides a first drive input for driving fan blades about an axis. A geared architecture is driven by a turbine section and is coupled to the fan section to provide a second drive input for driving the fan blades. A second electric motor assembly is coupled to rotate the geared architecture relative to a fixed structure for controlling a speed of the fan blades provided by a combination of the first drive input and the second drive input.

A system includes a torque sensor; and a hybrid power system. The hybrid power sensor includes a frame; an engine mounted on the frame; and a generator, the generator including: a generator rotor mechanically coupled to a shaft of the engine; and a generator stator coupled to the frame by the torque sensor. The torque sensor is configured to measure a torque on the generator stator.

The synchronous machine module includes a synchronous machine and a rotational speed controller for controlling a rotational speed of the synchronous machine, which rotational speed controller has a detector for detecting a variable which is formed by the effective power or is dependent thereon. The rotational speed controller is designed to set the rotational speed of the synchronous machine and/or the time profile thereof as a function of the detected variable and/or its time profile. The vehicle drive has such a synchronous machine module and a power generator, which in order to supply the synchronous machine module is connected thereto. The vehicle is, in particular, an aircraft and has such a vehicle drive and/or such a synchronous machine module.

The disclosure is directed to an optionally hybrid power system that may operate either as a traditional power system, deriving power from a single power source, or as a hybrid power system, deriving power from multiple types of power sources. An example optionally hybrid power system may include a gas turbine engine and one or more electric motors. When configured as a traditional power system the optionally hybrid power system may derive all power from the gas turbine engine. However, when configured as a hybrid power system, the one or more motors may be coupled to the optionally hybrid power system to supplement the power produced by the gas turbine engine. Additionally, an operator interface that may control the optionally hybrid power system may select from a plurality of operating modes that depend on the configuration of the optionally hybrid power system.

Methods and systems for a clean fuel, manned or unmanned aircraft, having an electric, low-emission or zero-emission lift and propulsion system, an integrated highway in the sky avionics system for navigation and guidance, a tablet-based motion command, or mission planning system to provide the operator with drive-by-wire style direction control, and automatic on-board-capability to provide traffic awareness, weather display and collision avoidance. Automatic computer monitoring by a programmed multiple-redundant autopilot control units control each motor-controller and motor to produce pitch, bank, yaw and elevation, while simultaneously restricting the flight regime that the pilot can command, to protect the pilot from inadvertent potentially harmful acts that might lead to loss of control or loss of vehicle stability. By using the results of the state measurements to inform motor control commands, the methods and systems contribute to the operational simplicity, reliability and safety of the vehicle.

An aircraft propulsion system with a drag reduction portion adapted to reduce skin friction on at least a portion of the external surface of an aircraft. The drag reduction portion may include an inlet to ingest airflow. The aircraft may also have an internally cooled electric motor adapted for use in an aerial vehicle. The motor may have its stator towards the center and have an external rotor. The rotor structure may be air cooled and may be a complex structure with an internal lattice adapted for airflow. The stator structure may be liquid cooled and may be a complex structure with an internal lattice adapted for liquid to flow through. A fluid pump may pump a liquid coolant through non-rotating portions of the motor stator and then through heat exchangers cooled in part by air which has flowed through the rotating portions of the motor rotor. The drag reduction portion and the cooled electric motor portion may share the same inlet.

An aircraft propulsion system with a drag reduction portion adapted to reduce skin friction on at least a portion of the external surface of an aircraft. The drag reduction portion may include an inlet to ingest airflow. The aircraft may also have an internally cooled electric motor adapted for use in an aerial vehicle. The motor may have its stator towards the center and have an external rotor. The rotor structure may be air cooled and may be a complex structure with an internal lattice adapted for airflow. The stator structure may be liquid cooled and may be a complex structure with an internal lattice adapted for liquid to flow through. A fluid pump may pump a liquid coolant through non-rotating portions of the motor stator and then through heat exchangers cooled in part by air which has flowed through the rotating portions of the motor rotor. The drag reduction portion and the cooled electric motor portion may share the same inlet.