A system is provided. The system includes a first inlet providing a medium from a source; a compressing device in communication with the first inlet; and at least one heat exchanger. The compressing device includes a compressor that receives the medium and a turbine downstream of the compressor. The system is powered by mechanical power from the medium and by electrical power through a motor. The motor input power is less than or equal to 0.5 kilowatt per pounds per minute of the medium compressed.

A turbojet engine including an intermediate casing including radial arms and a driveshaft for a gearbox for auxiliary machines of the turbojet engine, the driveshaft mounted in a radial arm, the radial arm including an intermediate bearing supporting the driveshaft, the intermediate bearing including plural rolling bearings supporting the driveshaft, the driveshaft including a first shaft element connected at one end to a mechanism providing mechanical transmission to an engine shaft of the turbojet engine, and a second shaft element connected at one end to a mechanism providing mechanical transmission to the box. The first shaft element and the second shaft element are linked by a connection including plural splines. A single plane transversely passes through the plural splines and the plural rolling bearings.

An inlet door state control system for an auxiliary power unit (APU) includes an inlet door configured to allow air into an inlet of the APU. The system also includes an actuator configured to open the inlet door. The system also includes an APU threshold switch connected to the actuator, the APU threshold switch configured to automatically change from an open position to a closed position when a predetermined APU operating condition is met. In the system, the actuator opens the inlet door when the APU threshold switch is in the closed position.

A gas turbine engine for an aircraft includes a compressor, a combustion chamber, and a turbine having at least one stator, and at least one rotor. Each stator and rotor is formed by a plurality of blades, a fluid channel is formed between two consecutive blades, and each blade has two opposing surfaces. The compressor is in fluid communication with a first group of stator channels, and the combustion chamber is in fluid communication with a second group of stator channels, such that heat exchange can be performed through two opposing surfaces of at least one stator blade. The outer and the inner walls define a duct for the passage of the heated fluid through the rotor blades, and the outer wall is also arranged for directing the compressed air towards the combustion chamber.

A turbomachine dual spool differential can include a gear assembly configured to combine a low pressure spool input and a high pressure spool input into a combination output to provide an output speed range smaller than a low pressure spool speed range alone. The gear assembly can include a ring gear, a sun gear, and a plurality of planetary gears disposed between the sun gear and the ring gear and meshed with the sun gear and the ring gear. The planetary gears can be rotationally connected to a carrier.

A high efficiency multifunction power system for an aircraft is provided. The system includes an AC generator and a multifunction power converter-controller module including at least one multifunction power converter-controller. The at least one multifunction power converter-controller is configured to function as a power converter and a controller to perform multiple operation modes.

An APU has a gas turbine engine and a starter generator to be selectively driven by the gas turbine engine. A sensor senses windmilling of components associated with the starter generator. A lock feature limits rotation within the starter generator when windmilling is sensed. A method of operation is also disclosed.

The invention relates to a removable reactivation pack for a turboshaft engine of a helicopter, comprising a gas generator equipped with a drive shaft, said turboshaft engine (6) being capable of operating in at least one standby mode during a stable flight of the helicopter, said removable pack comprising: a removable gearbox comprising a gearbox output shaft; controlled means for rotating said gearbox output shaft, referred to as reactivation means of said turboshaft engine; mechanical means for reversibly coupling said gearbox output shaft to said drive shaft of said gas generator.

A gas turbine engine including: a tail cone; a low pressure compressor; a low pressure turbine; a low speed spool interconnecting the low pressure compressor and the low pressure turbine; and an electric generator located within the tail cone, the electric generator being operably connected to the low speed spool, wherein the electric generator includes a coolant cavity in thermal communication with one or more components of the electric generator; a structural support housing at least partially enclosing the electric generator, the structural support housing including a forward wall located on a forward end of the structural support housing, wherein the forward wall includes a first opening; a first coolant conveying tube extending through the first opening to fluidly connect to the coolant cavity; and a first electrical connector tube extending through the first opening within the first coolant conveying tube to electrically connect to the electric generator.

A system and a method for the automatic starting of the engines of a twin-engine aircraft. When a first engine is made by the pilots of the aircraft to follow an automatic starting procedure, this engine follows the conventional four-phase starting cycle. The rotor of the high-pressure stage of the second engine is spun up for a predetermined duration and to a speed that is substantially constant and less than the nominal value during the starting cycle for the first engine. Once the starting cycle for the first engine is complete, the second engine is made by the pilots of the aircraft to follow an automatic starting procedure. The starting cycle for the second engine comprises just three phases.