An engine including a motor and a nacelle and a duct between the nacelle and the motor. The nacelle includes a fixed structure, a mobile assembly that is mobile between an advanced position and a retracted position to define a window between the duct and the outside, and a plurality of blades that are mobile in rotation between a stowed position and a deployed position, each one extending on either side of its axis of rotation with a first arm and a second arm. In the stowed position, the first arm is outside the duct and the second arm is inside the nacelle, and where, in the deployed position, the first arm is across the duct and the second arm projects out of the nacelle. With such blades, the flow of air is optimally directed towards the front without it being necessary to provide cascades.

A gas turbine engine including: a turbomachine coupled to a propeller of the gas turbine engine, the turbomachine being in fluid communication with an external environment through an air inlet; and an electric motor coupled to the propeller, wherein the air inlet is in fluid communication with a bypass duct having a selectively variable geometry.

A hybrid-electric propulsion system is provided. In one example aspect, the hybrid-electric propulsion system includes a power converter and a propulsor. The propulsor includes a gas turbine engine having a shaft and one or more bearings supporting the shaft. The propulsor also includes an electric machine electrically coupled with the power converter. The electric machine includes a stator assembly and a rotor assembly. The rotor assembly has a rotor and a rotor connection assembly. The rotor connection assembly operatively couples the rotor with the shaft. The rotor connection assembly has an insulated joint for interrupting common mode electric current from flowing from the rotor of the electric machine to the shaft. A grounding device is included to electrically ground the shaft. The power converter includes an electromagnetic interference filter to reduce common mode voltage reaching the electric machine.

A planetary gearbox is provided that includes a sun gear, a plurality of planet gear assemblies, each planet gear assembly having a main gear meshed with the sun gear, a fore lateral gear and an aft lateral gear disposed on opposite sides of the main gear and rotating therewith, a planet carrier rotatably supporting at least some of the planet gear assemblies, and at least one fore ring gear meshed with the fore lateral gears, at least one aft ring gear meshed with the aft lateral gears, wherein one of the sun gear, the planet carrier, and the ring gears is configured to be operatively connected to an input, one is configured to be operatively connected to an output, and rotation of a remaining one is limited.

An engine system includes a turbine engine including a compressor section, a combustor section having a burner, a turbine section, and a nozzle in an open-loop configuration. The engine system also includes a bottom-cycle apparatus and an exhaust heat exchanger downstream of the turbine section of the turbine engine configured to reject heat from the turbine engine to the bottoming-cycle apparatus and create a cooled turbine exhaust in the turbine engine. The engine system further includes an exhaust compressor arranged downstream of the exhaust heat exchanger and upstream of the nozzle of the turbine engine configured to compress the cooled turbine exhaust stream and increase a pressure of the cooled turbine exhaust stream prior to exiting the nozzle of the turbine engine.

An electric power system for a vehicle includes at least one electric machine, one or more power rectifiers, and a plurality of DC channels. The at least one electric machine includes a plurality of tooth-wound multi-phase windings that are substantially magnetically decoupled, and the at least one electric machine is mechanically balanced even if one of the plurality of windings is de-energized. The one or more power rectifiers are configured to produce rectified power from the power generated by the at least one electric machine. The plurality of DC channels are formed after the at least one power rectifier and are configured to provide DC power to one or more loads within a vehicle.

An engine system of an aircraft includes a gas turbine engine comprising at least one spool and at least one electric machine operably coupled with the at least one spool. A controller is configured to detect if the at least one spool of the gas turbine engine is in or is approaching an overspeed condition and apply a load to the at least one spool via the at least one electric machine.

Propulsion systems and methods of operation are provided. An exemplary propulsion system comprises a rotating element; a stationary element; an inlet duct having an inlet between the rotating and stationary elements, the inlet passing radially inward of the stationary element; a ducted fan disposed in the inlet duct downstream of the inlet and having an axis of rotation and a plurality of blades; a gas turbine engine core having a high pressure compressor, a combustor, and a high pressure turbine in serial relationship; and a booster compressor disposed between the ducted fan and the gas turbine engine core. At least one of the ducted fan and the booster compressor is driven by a variable speed power source such that the rotational speed of the ducted fan and/or booster compressor is controllable independently from the rotational speed of any rotor of the propulsion system.

A reverse flow gas turbine engine has a low pressure (LP) spool and a high pressure (HP) spool arranged sequentially in an axial direction. The LP spool comprises an LP compressor disposed forward of an LP turbine and drivingly connected thereto via an LP compressor gear train. The HP spool comprises an HP compressor in flow communication with the LP compressor, and an HP turbine disposed forward of the HP compressor and drivingly connected thereto via an HP shaft.

A multi-engine aircraft that includes two or more powerplants, each including an electric motor, and an electric power system controlling electrical distribution and operatively connected to the electric motors. The electric power system includes primary battery packs operatively connected to the electric motor of a respective one of the two or more powerplants, a reserve battery pack, and a switch interconnecting the reserve battery pack and the electric motors. The reserve battery pack is shared by the electric motors by the switch and configured such that the reserve battery pack provides electric power to a selected one of the electric motors.