An aircraft system includes an aircraft fuselage, an auxiliary power unit and an air inlet assembly. The auxiliary power unit is within the aircraft fuselage. The auxiliary power unit may be configured as or otherwise include an engine. The air inlet assembly includes an inlet orifice, an inlet duct and a door. The inlet duct fluidly couples the inlet orifice with an airflow inlet of the engine. The door is configured to pivot about a generally horizontal pivot axis between an open position and a closed position. The door opens the inlet orifice in the open position and substantially closes the inlet orifice in the closed position.

Aircraft support structures, systems, and methods are disclosed. In one embodiment, an aircraft system includes a rotating component and a support (e.g. strut) that supports the rotating component. The support includes a locking assembly (P1) that is configured to lock, automatically, an inner member (214) of the support with respect to an outer member (208) of the support for stiffening the support in response to reaching or exceeding a predetermined threshold amount of displacement, load, stress, or rotation. The aircraft support structures, systems, and methods herein utilize self-locking and self-unlocking supports (e.g. struts) for increasing or decreasing a stiffness of the support.

A method and architecture to optimize an entire traction system available on a helicopter by using an auxiliary engine to provide energy to equipment and accessories of the helicopter connected to the engines. Main engines and an APU unit, as an auxiliary engine, include a gas generator connected to, for the main engines, a reduction gearbox and an accessory gearbox for mechanical, electrical, and/or hydraulic power take-off and connected to, for the APU unit, at least one power conversion member. The power conversion member of the APU unit is connected to the equipment and accessories by the reduction gearbox and/or the accessory gearbox of the main engines.

A system and method for controlling a position of an inlet door of an auxiliary power unit are provided. A first control signal comprising instructions for opening the inlet door to a selected one of at least a first position and a second position is output. A possible failure in a feedback signal associated with the selected one of the at least first position and second position is detected and a second control signal comprising instructions for opening the inlet door to the other one of the at least first position and second position is then output.

A safety open and closing system for an overpressure door on fuselage of an aircraft. Wherein the safety opening and closing system allows safe access through the overpressure door to the compartment. The safety open and closing system including an assembly of a hollow beam, a blocking bar in the hollow beam, a spring biasing the blocking bar with respect to the hollow beam and a lever at the end of the blocking beam which pivots between a position A that allows closure of the overpressure door and a position B preventing closure of the door.

The invention relates to an electric power distribution box for an aircraft, comprising a frame (3) containing at least one power connector (7) formed of one or more slide rails (8) that are able to interact with one end (11) of a power circuit board (9), said power circuit board (9) comprising at least one switching element (13) for an electric power distribution plate. The invention also relates to an electric power distribution assembly (1) comprising such a power distribution box.

Electric aircraft power plants and associated methods are provided. One power plant includes an emergency power unit (EPU) for providing electric power in the event of a malfunction of a battery pack of an electric aircraft to permit the electric aircraft to make an emergency maneuver. The EPU includes a rocket engine for generating a stream of exhaust fluid using a rocket propellant, a turbine operatively connected to extract energy from the stream of exhaust fluid generated by the rocket engine, and an electric generator operatively connected to be driven by the turbine and to supply electric power to an electric motor propelling the electric aircraft.

Methods and systems for operating an auxiliary power unit (APU) of an aircraft are described. The method comprises obtaining external environment parameters of the aircraft, determining an available output power for the APU as a function of the external environment parameters, and setting an overcurrent protection threshold of the APU to a level associated with the available output power.

This invention concerns an aircraft propulsion system in which an engine has an engine core comprising a compressor, a combustor and a turbine driven by a flow of combustion products of the combustor. At least one propulsive fan generates a mass flow of air to propel the aircraft. An electrical energy store is provided on board the aircraft. At least one electric motor is arranged to drive the propulsive fan and the engine core compressor. A controller controls the at least one electric motor to mitigate the creation of a contrail caused by the engine combustion products by altering the ratio of the mass flow of air by the propulsive fan to the flow of combustion products of the combustor. The at least one electric motor is controlled so as to selectively drive both the propulsive fan and engine core compressor.

A mount structure for mounting an ancillary engine unit to a gas turbine engine is provided. The mount structure has plural elongate struts which each extend from a connector portion at one end of the strut to a fastening portion at the other end of the strut. The housing of the ancillary engine unit is formed of a first material having a first coefficient of thermal expansion, and the elongate struts are formed of a second material having a second coefficient of thermal expansion. Each elongate strut extends away from its connector portion in a direction which is crosswise to the direction of the hypothetical differential thermal strain at that connector portion. The mount structure further has a containment bracket which is configured to contain each connector portion.