The invention relates to an aircraft comprising a fuselage (1), which is propelled by a turbine engine with two coaxial fans, namely an upstream fan (7) and a downstream fan (8), driven by two contra-rotating rotors (5, 6) of a power turbine (3). The two fans (7, 8) and the turbine (3) are integrated into a nacelle (14) which projects downstream from the fuselage (1) and through which air flows. According to the invention, at least one of the fans (7, 8) of the aircraft and, in particular, the downstream fan (8) comprises variable-spacing blades, and at least one stator-forming variable-spacing blade ring (25) in the aircraft is placed upstream of the upstream fan (7). The variable-spacing stator blades (25) and the variable-spacing blades of the downstream fan (8) are mutually configured to direct the air flow in a first mode in which the air flows through the nacelle (14) from upstream to downstream and in a second mode in which the air is pushed back upstream through the nacelle (14).

Provided is a transition duct that forms an annular gas flow channel through which a main flow gas flows from a high-pressure turbine to a low-pressure turbine, wherein the gas flow channel has an inner peripheral flow channel surface and an outer peripheral flow channel surface, the inner peripheral flow channel surface and the outer peripheral flow channel surface extend radially outward while angles of inclination relative to an axial direction of a rotating shaft change from the high-pressure turbine (first turbine) toward the low-pressure turbine (second turbine), and an inner peripheral maximum inclined part is provided in a range A2 that extends in the axial direction from a position of alignment with an outer peripheral maximum inclined part to a position advanced toward the low-pressure turbine by a length no more than 20% of the duct length.

Provided is a transition duct that forms an annular gas flow channel through which a main flow gas flows from a high-pressure turbine to a low-pressure turbine, wherein the gas flow channel has an inner peripheral flow channel surface and an outer peripheral flow channel surface, the inner peripheral flow channel surface and the outer peripheral flow channel surface extend radially outward while angles of inclination relative to an axial direction of a rotating shaft change from the high-pressure turbine (first turbine) toward the low-pressure turbine (second turbine), and an inner peripheral maximum inclined part is provided in a range A2 that extends in the axial direction from a position of alignment with an outer peripheral maximum inclined part to a position advanced toward the low-pressure turbine by a length no more than 20% of the duct length.

Controller for controlling a bleed valve including a first body with an internal cavity connected to an air inlet port and an air outlet port, a second body including a chamber, a mobile member in the cavity and in the chamber, connecting the two bodies. The member is mobile between a position whereby the ports fluidly communicate and a position whereby the ports are isolated, the member further including two pistons housed in the chamber and defining in this chamber at least two spaces. The controller also includes a fluid supply for at least one of the spaces for the purpose of moving the pistons in the chamber.

Controller for controlling a bleed valve including a first body with an internal cavity connected to an air inlet port and an air outlet port, a second body including a chamber, a mobile member in the cavity and in the chamber, connecting the two bodies. The member is mobile between a position whereby the ports fluidly communicate and a position whereby the ports are isolated, the member further including two pistons housed in the chamber and defining in this chamber at least two spaces. The controller also includes a fluid supply for at least one of the spaces for the purpose of moving the pistons in the chamber.

A highly efficient gas turbine engine includes the fan of the gas turbine engine driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

A highly efficient gas turbine engine includes the fan of the gas turbine engine driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.

A gas turbine engine includes a main compressor section and a turbine section. The turbine section has a first turbine blade and vane and a downstream turbine component. A tap is configured to tap air from the compressor section at a location upstream of a most downstream location. The tap is connected to a heat exchanger. The heat exchanger is connected to a cooling compressor. The cooling compressor is connected to the downstream turbine component. A second tap is configured to tap air from a location in the main compressor section. The second tap is connected through a check valve to a line leading to the downstream turbine component. A control operates the cooling compressor such that when the cooling compressor is operating, air downstream of the cooling compressor is at a pressure higher than the pressure of the second tap, and the control is operational to selectively drive the cooling compressor at high power operation of an associated gas turbine engine, and to stop operation of the cooling compressor at lower power operations, such that air is delivered through the cooling compressor to the downstream turbine component at the high power operations, and air is delivered from the second tap at least some time when the cooling compressor is not operational. A method is also disclosed.

A gas turbine engine includes a main compressor section and a turbine section. The turbine section has a first turbine blade and vane and a downstream turbine component. A tap is configured to tap air from the compressor section at a location upstream of a most downstream location. The tap is connected to a heat exchanger. The heat exchanger is connected to a cooling compressor. The cooling compressor is connected to the downstream turbine component. A second tap is configured to tap air from a location in the main compressor section. The second tap is connected through a check valve to a line leading to the downstream turbine component. A control operates the cooling compressor such that when the cooling compressor is operating, air downstream of the cooling compressor is at a pressure higher than the pressure of the second tap, and the control is operational to selectively drive the cooling compressor at high power operation of an associated gas turbine engine, and to stop operation of the cooling compressor at lower power operations, such that air is delivered through the cooling compressor to the downstream turbine component at the high power operations, and air is delivered from the second tap at least some time when the cooling compressor is not operational. A method is also disclosed.

A highly efficient gas turbine engine is provided. The fan of the gas turbine engine is driven from a turbine via a gearbox, such that the fan has a lower rotational speed than the driving turbine, thereby providing efficiency gains. The efficient fan system is mated to a core that has low cooling flow requirements and/or high temperature capability, and which may have particularly low mass for a given power.