An example aircraft includes a parallel propulsion unit, the parallel propulsion unit comprising: a propulsor configured to provide forward propulsion of the aircraft; a gas turbine engine configured to drive the propulsor; an electrical machine configured to generate, for output via one or more electrical busses, electrical energy using mechanical energy derived from the gas turbine engine; and a power sharing module configured to control a ratio of the mechanical energy used to drive the propulsor and used to generate electrical energy; and a plurality of series propulsion units, each series propulsion unit comprising a respective propulsor of a plurality of propulsors that are configured to provide vertical propulsion of the aircraft and a respective electrical machine of a plurality of electrical machines, each respective electrical machine configured to drive a respective propulsor of the plurality of propulsors using electrical energy received from one or more electrical busses.

An aircraft propulsion system having a variable airflow capture area is provided. The propulsion system includes a main propulsion source and an auxiliary propulsion source. In a first mode, the auxiliary propulsion source is stowed within an aerodynamic profile of the aircraft, and the main propulsion source provides all of the propulsion force for powering flight of the aircraft. In a second mode, the auxiliary propulsion source is deployed to augment the airflow capture area of the main propulsion source and increase an overall airflow capture area of the propulsion system. In the second mode, the auxiliary power source is operated by power extracted from the main propulsion source. The main propulsion source may include one or more low bypass ratio engines. The auxiliary power source may include one or more auxiliary thrust fans coupled at a plurality of locations on the aircraft.

An aircraft turbine engine includes a gas generator and a fan arranged upstream from the gas generator and configured to generate a main gas flow, one portion of which flows in a flow path of the gas generator to form a primary flow, and another portion of which flows in a flow path around the gas generator to form a secondary flow. The gas generator has a low-pressure body with a rotor driving the fan and a low-pressure compressor situated upstream from an intermediate housing. The turbine engine also includes an electric machine, mounted coaxially downstream from the fan and upstream from the intermediate housing. An intermediate shaft is driven by the rotor of the low-pressure body and drives rotors of the electric machine and of the low-pressure compressor.

An aircraft turbine engine includes a gas generator and a fan arranged upstream from the gas generator and configured to generate a main gas flow, one portion of which flows in a flow path of the gas generator to form a primary flow, and another portion of which flows in a flow path around the gas generator to form a secondary flow. The gas generator has a low-pressure body with a rotor driving the fan and a low-pressure compressor situated upstream from an intermediate housing. The turbine engine also includes an electric machine, mounted coaxially downstream from the fan and upstream from the intermediate housing. An intermediate shaft is driven by the rotor of the low-pressure body and drives rotors of the electric machine and of the low-pressure compressor.

The disclosure is directed to drive assemblies for unmanned aerial vehicles (UAVs). Specifically, the disclosure is directed to hybrid drive assembly and control system for UAVs, utilizing indexed belt tension modulation to couple and decouple an electric motor and an internal combustion engine.

A computer-implemented method for optimally operating a hybrid-electric propulsion system by control of equipment dynamics. Prior to start of a mission, an original energy management plan is generated which is calculated to minimize estimated life-cycle operating costs for the vehicle during the mission. During an initial portion of the mission, operations of first and second power sources, a power distribution system, and a propulsion system are controlled such that a power mixture is supplied to the propulsion system from the first and second power sources in accordance with the original energy management plan. During the initial portion of the mission, a modified energy management plan is generated which is calculated to minimize estimated life-cycle operating costs for the vehicle. During a subsequent portion of the mission, operations of the first and second power sources, power distribution system, and propulsion system are controlled such that a power mixture is supplied to the propulsion system from the first and second power sources in accordance with the modified energy management plan.

The present disclosure provides an apparatus with a prime mover coupled to a generator that is directly electrically coupled to an electric motor. A propeller or fan may be coupled to and driven by the electric motor. A bi-directional power converter may be coupled to the generator and further coupled to an energy storage device. The energy storage device may be selectively coupled to the electric motor. Methods of using the apparatus are also provided.

A cross flow fan to be incorporated into an aircraft fuselage comprises an ingestion fan rotor to be positioned in a tail section of an aircraft fuselage to reduce boundary layer air from a top surface of the fuselage and to drive the air away from the top surface, and a drive arrangement for the ingestion fan rotor. An aircraft is also disclosed.

A power plant for a small aircraft with a gas turbine engine that drives a number of electric generators, where a gear box transmit power from the engine shaft to the number of generators, the gear box having a single input shaft that drives a number of driven gears with each driven gear having a generator drive shaft that extends out both sides, and an electric generator connected to each side of the drive shaft. A compact arrangement of generators are formed where each generator can be disengaged from the drive shaft to regulate total electrical output or to prevent a damaged generator from causing damage to other parts of the system or aircraft.

The present disclosure provides an apparatus with a prime mover coupled to a generator that is directly electrically coupled to an electric motor. A propeller or fan may be coupled to and driven by the electric motor. A bi-directional power converter may be coupled to the generator and further coupled to an energy storage device. The energy storage device may be selectively coupled to the electric motor. Methods of using the apparatus are also provided.