A rotary wing aircraft having an electrical installation including at least one thermopile for powering at least one piece of electrical load equipment. Technical specifications for the thermopile specify: a usable power for supplying to the load equipment in the range 20 W to 200 kW, a power rise time lapse lying in the range 3 s to 30 s, and a low operating time for usefully supplying a predetermined quantity of electrical energy lying in the range 10 s to 180 s. The invention applies in particular to rotary wing aircraft.

An electric power distribution system for an aircraft is provided, which includes an engine gearbox, a power distribution center, two or more three-phase synchronous electric power generators, a neutral current transformer per generator, a single set of power feeder wires, and a single generator control unit (GCU). The generators are connected in parallel with each other, and connected with the power distribution center by the same set of power feeder wires. The GCU is electrically coupled with each generator to feed the generator with an excitation field current, and with each neutral current transformer to sense an instantaneous neutral-current value. The GCU is adapted to perform a generator voltage regulation loop based on a desired voltage value and the at least two sensed instantaneous neutral-current values by individually modifying the excitation field current of each generator.

An aircraft propulsion power plant for use in an aircraft includes one or more core engines housed in an airframe of the aircraft, one or more secondary propulsion units, each of the one or more secondary propulsion units being removably attached to the airframe, and one or more power transmission means, each of the one or more power transmission means being configured to transmit mechanical power from the or each core engine to a corresponding one of the or each secondary propulsion unit when the or each secondary propulsion unit is attached to the airframe.

The invention relates to a method for providing predefined desired drive characteristics (38, 50) in an aircraft, characterized by the following steps: driving a thrust generation element of the aircraft by means of an electric motor that has actual drive characteristics (34) which include at least some of the desired drive characteristics (38, 50) but are also partly different therefrom; andhaving a control device adjust operating points of the electric motor exclusively according to the desired drive characteristics (38, 50).

This disclosure is directed to a single blade propeller and systems, devices, and techniques pertaining to assisting in critical stages of flight (e.g., takeoff, landing, emergency situations, etc.) in vertical takeoff and landing (VTOL) aircraft. The single blade propeller may be incorporated into fixed and rotary wing VTOL aircraft as part of a first propulsion system. The first propulsion system may include one or more single blade propellers driven by electric motors, combustion engines, and/or hybrid engines. Each of the single blade propellers may include a lift-producing blade and a counterweight opposite the lift-producing blade. As each of the single blade propellers spins, it may produce lift in a direction approximately perpendicular to the horizon to effect vertical flight.

UAV configurations and battery augmentation for UAV internal combustion engines, and associated systems and methods are disclosed. A representative configuration includes a fuselage, first and second wings coupled to and pivotable relative to the fuselage, and a plurality of lift rotors carried by the fuselage. A representative battery augmentation arrangement includes a DC-powered motor, an electronic speed controller, and a genset subsystem coupled to the electronic speed controller. The genset subsystem can include a battery set, an alternator, and a motor-gen controller having a phase control circuit configurable to rectify multiphase AC output from the alternator to produce rectified DC feed to the DC-powered motor. The motor-gen controller is configurable to draw DC power from the battery set to produce the rectified DC feed.

Apparatus and methods for controlling yaw of a rotorcraft in the event of one or both of low airspeed and engine failure are disclosed. A yaw propulsion provides a yaw moment at low speeds. The yaw propulsion device may be an air jet or a fan. A pneumatic fan may be driven by compressed air released into a channel surrounding an outer portion of the fan. The fan may be driven by hydraulic power. Power for the yaw propulsion device and other system may be provided by a hydraulic pump and/or generator engaging the rotor. The generator may be used to charge a battery during autorotation or descending. Low speed yaw control may be provided by auxiliary rudders positioned within the stream tube of a prop. The auxiliary rudders may one or both of fold down and disengage from rudder controls when not in use.

A control for a hybrid turbo electric aero-propulsion system prioritizes and optimizes the operating parameters, according to a desired optimization objective, for and across a number of different control optimization subsystems of the hybrid turbo electric aero-propulsion system. The control subsystems may include, for example, a propulsion control optimization subsystem and a power plant control optimization subsystem. The optimizations may be based on a system model, which is developed and updated during the operation of the hybrid turbo electric aero-propulsion system.

Hybrid aircraft power plants are provided together with associated systems and methods for operating such hybrid aircraft power plants. A hybrid aircraft power plant includes a thermal engine, an electric motor and one or more controllers operatively connected to the thermal engine and to the electric motor. The thermal engine and the electric motor are drivingly connected to an air mover of an aircraft via a combining gear train. The one or more controllers are configured to govern an actual output torque of the electric motor to reduce an error between a target operating speed for the air mover and an actual operating speed of the air mover, and govern an output of the thermal engine to reduce an error between a target output torque for the electric motor and the actual output torque of the electric motor.

A method for testing a hybrid power plant equipping a rotary-wing aircraft comprising at least one lift rotor, the hybrid power plant being configured to rotate the at least one lift rotor, the hybrid power plant comprising at least one heat engine configured to rotate the at least one lift rotor; and at least one electric motor supplied with electrical energy by at least one electrical power source, the at least one electric motor being configured to rotate the at least one lift rotor at least when at least one of the at least one heat engine fails.