An aircraft includes a fuselage coupled to a wing having a root section and first and second outboard sections each having first and second wing layers pivotably coupled to respective outboard ends of the root section. A thrust array is coupled to the wing. A power system is operably associated with the thrust array to provide power to each of a plurality of propulsion assemblies. A flight control system is operably associated with the thrust array and the wing. The flight control system is operable to control the thrust output from the propulsion assemblies and the configuration of the wing. In a thrust-borne vertical lift mode, the wing has a split wing configuration such that the thrust array forms a two dimensional thrust array. In the wing-borne forward flight mode, the wing has a monoplane configuration such that the thrust array forms a one dimensional thrust array.

An autogyro includes a fuselage with a rotor. The rotor includes rotor blades which are arranged on an upper face of the fuselage, and a rotor drive which temporarily drives the rotor via a first motor. The rotor blades autorotate via an airflow.

An anti-torque system (10) for a helicopter (1) is described that comprises: an electric power supply unit (15); at least one first rotor (17), operatively connected to an electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a first variable angular speed; and at least one second rotor (25) operatively connected to electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a second variable angular speed.

The present invention discloses a fuel-electric hybrid multi-axis rotor-type unmanned aerial vehicle which relates to the field of unmanned aerial vehicles. The fuel-electric hybrid multi-axis rotor-type unmanned aerial vehicle includes an unmanned aerial vehicle frame, a lifting rotor, a posture adjusting rotor, a fuel engine, a motor, a fuel tank and a power supply device; the fuel engine, the motor, the fuel tank and the power supply device are mounted on the unmanned aerial vehicle frame; the fuel tank supplies fuel to the fuel engine; the fuel engine is configured to drive the lifting rotor; and the motor is powered by the power supply device and configured to drive the posture adjusting rotor. A main purpose is to enable the multi-axis rotor-type unmanned aerial vehicle having a large-load and long-duration flight function to quickly and precisely adjust the flight direction and flight speed.

An aircraft includes an engine and a first variable frequency generator having a first rotor that is rotatable at a rate that is based on a rotational rate of the engine to cause the first variable frequency generator to generate a first multiphase signal. The aircraft further includes a second variable frequency generator having a second rotor that is rotatable at the rate to cause the second variable frequency generator to generate a second multiphase signal. The first multiphase signal is phase aligned with the second multiphase signal. The aircraft further includes one or more switches coupled to a first electrical system and configured to selectively provide power to the first electrical system based on either the first multiphase signal or the second multiphase signal.

An assembly for an aircraft having a propeller, including a wheel well for a retracted landing gear, first and second cooling ducts; and an engine assembly having an engine shaft configured for driving engagement with the propeller, the engine assembly including a coolant circulation system for circulation of a liquid coolant, a lubricant circulation system for circulation of a lubricant, a first heat exchanger in fluid communication with at least the coolant circulation system, and a second heat exchanger in fluid communication with at least the lubricant circulation system. Each heat exchanger is positioned and configured for receiving a cooling airflow from the respective cooling duct. The wheel well is located between the heat exchangers. A method of cooling a lubricant and a liquid coolant of an engine assembly is also discussed.

A system is described that includes a turbine engine including an engine fan including one or more variable-pitch blades driven by a shaft, which rotates at a rotational speed which depends on a pitch of the one or more variable-pitch blades of the engine fan. The system further includes a generator configured to produce alternating-current (AC) electricity at a particular frequency relative to the rotational speed of the shaft. The system also includes a propulsor, which includes a propulsor motor and a propulsor fan. The propulsor motor is configured to drive, based on the AC electricity produced by the generator, the propulsor fan. The system includes a controller configured to control the particular frequency of the AC electricity by at least controlling the pitch of the one or more variable-pitch blades of the engine fan and thereby the rotational speed of the generator.

An aircraft propulsion plant including an electric motor having a rotor and a stator mechanically linked to a base which can be mounted at the rear of an aircraft fuselage, a fan rotated by the rotor, a set of fixed blades located downstream of the fan, and a nacelle comprising an outer casing and a fan casing surrounding the fan and the set of fixed blades. The nacelle is mechanically linked to the base through the set of fixed blades. This configuration enables a cooling circuit to be formed for enabling the heat produced by the electric motor at the location of the stator to be evacuated towards the fixed blades and the nacelle where it is dissipated. Furthermore, this heat may be used for the de-icing of the nacelle lip.

A compounding drive includes an input member, an epicyclical gear arrangement connected to the input member, an output member connected to the epicyclical gear arrangement, and a hydraulic pump/motor set. The hydraulic pump/motor set connects the epicyclical gear arrangement to the output member through an overrunning clutch for unidirectional communication of mechanical rotation between the input member and the output member. Engine arrangements, aircraft, and methods of compounding internal combustion engines are also described.