Abstract: A propulsion system (1) for a helicopter, comprising a turboshaft engine (2) with a linked turbine and an electric machine (3) capable of operating as an electric motor, the turboshaft engine (2) and the electric machine (3) being capable of driving in rotation at least one main rotor (5) intended to be coupled to a rotating wing (6) characterised in that it comprises means of coupling and decoupling (14) in rotation between a rotor (3a) of the electric machine (3) and a rotor (2a) of the turboshaft engine (2), the means of coupling and decoupling (14) being capable of allowing the rotor (2a) of the turboshaft engine (2) to be driven in rotation with the aid of the electric machine (3), in a first state of the propulsion system (1), and capable of allowing the rotor (2a) of the turboshaft engine (2) and the rotor (3a) of the electric machine (3) to be decoupled in rotation, in a second state of the propulsion system (1).

Abstract: The invention relates to a system (12) for the recovery of energy from exhaust gases from at least one turboshaft engine, comprising a turbine (34) fitted rotatably around a recovery shaft (40), adapted to bleed off at least a part (14) of the exhaust gases, known as bleed gases (14), and to expand said bleed gases (14) to become expanded gases (42) at a pressure below atmospheric pressure, a first heat exchanger (44), adapted to use a cold source (45) to cool said expanded gases (42) to become cooled gases (46), and a compressor (36) fitted rotatably around said recovery shaft (40), adapted to compress said cooled gases (46) to atmospheric pressure.

Abstract: The invention relates to a turboshaft engine comprising a gas generator (5) that is capable of being rotated, and a free turbine (6) that is rotated by the gases of said gas generator (5), characterized in that it comprises a device (20) for spontaneously mechanically coupling said gas generator (5) and said free turbine (6) that is capable of mechanically and spontaneously connecting said gas generator (5) and said free turbine (6) as soon as the ratio of the rotational speed (NGG) of said gas generator to the rotational speed (NTL) of said free turbine reaches a predetermined threshold value.

Abstract: The invention relates to an architecture of a propulsion system of a multiple-engine helicopter comprising turboshaft engines (5, 6), characterised in that it comprises: at least one hybrid turboshaft engine (5) that is capable of operating in at least one standby mode during a stable flight of the helicopter, the other turboshaft engines (6) operating alone during this stable flight; an air turbine (30) that is mechanically connected to the gas generator (17) of the hybrid turboshaft engine (5) and is suitable for rotating said gas generator (17); means for withdrawing pressurised air from the gas generator (27) of a running turboshaft engine (6); and a duct (31) for routing this withdrawn air to said air turbine (30).

Abstract: A turbine engine for a helicopter, the helicopter including a main gearbox, a rotor, and a speed-reducing device housed entirely within the main gearbox of the helicopter while also being connected to the rotor, the turbine engine including a casing, a gas generator with a gas generator shaft, and a free turbine for being driven in rotation by a gas stream generated by the gas generator, the free turbine including a free turbine shaft. When the turbine engine is fastened to the gearbox of the helicopter, the free turbine shaft extends axially into the main gearbox of the helicopter to be connected directly to the speed-reducing device.

Abstract: A method and configuration to optimize an entire traction system available on a helicopter including an auxiliary engine by allowing the engine to provide non-propulsive and/or propulsive power during flight. The auxiliary engine is coupled to participate directly in providing mechanical or electrical propulsive power and electrical non-propulsive power to the aircraft. An architecture configuration includes an on-board power supply network, two main engines, and a system for converting mechanical energy into electrical energy between a main gearbox to the propulsion members and a mechanism receiving electrical energy including the on-board network and power electronics in conjunction with starters of the main engines. An auxiliary power engine provides electrical energy to the mechanism for receiving electrical energy via the energy conversion system and a mechanism for mechanical coupling between the auxiliary engine and at least one propulsion member.

Abstract: The invention relates to a system (12) for the recovery of energy from exhaust gases from at least one turboshaft engine, comprising a turbine (34) fitted rotatably around a recovery shaft (40), adapted to bleed off at least a part (14) of the exhaust gases, known as bleed gases (14), and to expand said bleed gases (14) to become expanded gases (42) at a pressure below atmospheric pressure, a first heat exchanger (44), adapted to use a cold source (45) to cool said expanded gases (42) to become cooled gases (46), and a compressor (36) fitted rotatably around said recovery shaft (40), adapted to compress said cooled gases (46) to atmospheric pressure.

Abstract: 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.

Abstract: The invention relates to a turboshaft engine comprising a gas generator (5) that is capable of being rotated, and a free turbine (6) that is rotated by the gases of said gas generator (5), characterised in that it comprises a device (20) for spontaneously mechanically coupling said gas generator (5) and said free turbine (6) that is capable of mechanically and spontaneously connecting said gas generator (5) and said free turbine (6) as soon as the ratio of the rotational speed (NGG) of said gas generator to the rotational speed (NTL) of said free turbine reaches a predetermined threshold value.

Abstract: The invention relates to an architecture of a propulsion system of a multiple-engine helicopter comprising turboshaft engines (5, 6), characterised in that it comprises: at least one hybrid turboshaft engine (5) that is capable of operating in at least one standby mode during a stable flight of the helicopter, the other turboshaft engines (6) operating alone during this stable flight; an air turbine (30) that is mechanically connected to the gas generator (17) of the hybrid turboshaft engine (5) and is suitable for rotating said gas generator (17); means for withdrawing pressurised air from the gas generator (27) of a running turboshaft engine (6); and a duct (31) for routing this withdrawn air to said air turbine (30).

Abstract: A method and architecture for recombining power of a turbomachine improving on problems of size, mass, or reliability. In the method energy is recovered in an exhaust nozzle and converted and recirculated using a mechanical and/or electrical power recombining mechanism. An example of an architecture of a turbomachine includes a main turbine engine and a heat exchanger positioned in the exhaust nozzle and coupled, via pipes, to an independent system that converts thermal energy into mechanical energy. This independent system is connected to a localized mechanical recombination mechanism via a power shaft to supply power to a power transmission shaft according to aircraft requirements.

Abstract: A mechanical protection device including: a transmission shaft having a main axis of rotation and an element that is frangible under a torsional overload; a movable member secured to the transmission shaft to rotate about the main axis and configured to move radially outwards relative to the main axis from a first position to a second position; a spring urging the movable member towards the first position; and a tangential abutment configured to stop rotation of the movable member about the main axis when the movable member is in the second position. The movable member and the spring are calibrated so that from a predetermined trigger angular speed the movable member moves from the first position to the second position under effect of centrifugal force greater than prestress of the spring.

Abstract: A method and configuration to optimize an entire traction system available on a helicopter including an auxiliary engine by allowing the engine to provide non-propulsive and/or propulsive power during flight. The auxiliary engine is coupled to participate directly in providing mechanical or electrical propulsive power and electrical non-propulsive power to the aircraft. An architecture configuration includes an on-board power supply network, two main engines, and a system for converting mechanical energy into electrical energy between a main gearbox to the propulsion members and a mechanism receiving electrical energy including the on-board network and power electronics in conjunction with starters of the main engines. An auxiliary power engine provides electrical energy to the mechanism for receiving electrical energy via the energy conversion system and a mechanism for mechanical coupling between the auxiliary engine and at least one propulsion member.

Abstract: 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.

Abstract: A turbine engine, for example for a helicopter, the engine including a gas generator and a free turbine driven in rotation by a gas stream generated by the gas generator, the turbine engine further including a reversible electric machine for coupling to the gas generator, the reversible electric machine configured to set the gas generator into rotation during a stage of starting the turbine engine. To generate electricity, the reversible electric machine is also configured to be coupled to the free turbine after the turbine engine has started.

Abstract: A mechanical protection device including: a transmission shaft having a main axis of rotation and an element that is frangible under a torsional overload; a movable member secured to the transmission shaft to rotate about the main axis and configured to move radially outwards relative to the main axis from a first position to a second position; a spring urging the movable member towards the first position; and a tangential abutment configured to stop rotation of the movable member about the main axis when the movable member is in the second position. The movable member and the spring are calibrated so that from a predetermined trigger angular speed the movable member moves from the first position to the second position under effect of centrifugal force greater than prestress of the spring.

Abstract: A method and architecture for recombining power of a turbomachine improving on problems of size, mass, or reliability. In the method energy is recovered in an exhaust nozzle and converted and recirculated using a mechanical and/or electrical power recombining mechanism. An example of an architecture of a turbomachine includes a main turbine engine and a heat exchanger positioned in the exhaust nozzle and coupled, via pipes, to an independent system that converts thermal energy into mechanical energy. This independent system is connected to a localized mechanical recombination mechanism via a power shaft to supply power to a power transmission shaft according to aircraft requirements.

Abstract: A turbine engine for a helicopter, the helicopter including a main gearbox, a rotor, and a speed-reducing device housed entirely within the main gearbox of the helicopter while also being connected to the rotor, the turbine engine including a casing, a gas generator with a gas generator shaft, and a free turbine for being driven in rotation by a gas stream generated by the gas generator, the free turbine including a free turbine shaft. When the turbine engine is fastened to the gearbox of the helicopter, the free turbine shaft extends axially into the main gearbox of the helicopter to be connected directly to the speed-reducing device.

Abstract: A turbine engine, for example for a helicopter, the engine including a gas generator and a free turbine driven in rotation by a gas stream generated by the gas generator, the turbine engine further including a reversible electric machine for coupling to the gas generator, the reversible electric machine configured to set the gas generator into rotation during a stage of starting the turbine engine. To generate electricity, the reversible electric machine is also configured to be coupled to the free turbine after the turbine engine has started.