A gas turbine engine having an interdigitated turbine assembly including a first turbine rotor and a second turbine rotor, wherein a total number of stages at the interdigitated turbine assembly is between 3 and 8, and an average stage pressure ratio at the interdigitated turbine assembly is between 1.3 and 1.9. A gear assembly is configured to receive power from the interdigitated turbine assembly, and a fan assembly is configured to receive power from the gear assembly. The interdigitated turbine assembly and the gear assembly are together configured to allow the second turbine rotor to rotate at a second rotational speed greater than a first rotational speed at the first turbine rotor. The fan assembly and the gear assembly are together configured to allow the fan assembly to rotate at a third rotational speed less than the first rotational speed and the second rotational speed. The interdigitated turbine assembly, the gear assembly, and the fan assembly together have a maximum AN.sup.2 at the second turbine rotor between 30 and 90.

A gas turbine engine has a first spool having a low pressure compressor section disposed forward of an air inlet along a direction of travel of the engine, and a low pressure turbine section disposed forward of the low pressure compressor section and drivingly engaged thereto. A second spool has a high pressure compressor section disposed forward of the low pressure compressor section, and a high pressure turbine section disposed forward of the high pressure compressor section and drivingly engaged thereto. The high pressure turbine section is disposed aft of the low pressure turbine section. An output drive shaft drivingly engages the low pressure turbine section and extends forwardly therefrom to drive a rotatable load. A method of operating a gas turbine engine is also discussed.

A gas turbine engine has a first spool having a low pressure compressor section disposed forward of an air inlet along a direction of travel of the engine, and a low pressure turbine section disposed forward of the low pressure compressor section and drivingly engaged thereto. A second spool has a high pressure compressor section disposed forward of the low pressure compressor section, and a high pressure turbine section disposed forward of the high pressure compressor section and drivingly engaged thereto. The high pressure turbine section is disposed aft of the low pressure turbine section. An output drive shaft drivingly engages the low pressure turbine section and extends forwardly therefrom to drive a rotatable load. A method of operating a gas turbine engine is also discussed.

The invention relates to a turbomachine of an aircraft comprising an outer casing (2) delimiting with an inner hub (3), a flow path (1) of a gas stream in which is disposed a low-pressure turbine configured to rotationally drive a low-pressure shaft; said turbomachine comprising, in the direction of flow of the gas stream, a first propeller (31); and a second propeller (32) downstream of the first propeller, the first propeller (31) being rotationally driven by said low-pressure shaft and the second propeller being rotationally driven by an electric motor (70), the second propeller (32) being further disposed at a distance between 1.5 and 4 cord lengths (LC1) from the first propeller (31) defined between the respective axes of shimming (A31, A32) of each of the first and second propellers.

The invention relates to a turbomachine of an aircraft comprising an outer casing (2) delimiting with an inner hub (3), a flow path (1) of a gas stream in which is disposed a low-pressure turbine configured to rotationally drive a low-pressure shaft; said turbomachine comprising, in the direction of flow of the gas stream, a first propeller (31); and a second propeller (32) downstream of the first propeller, the first propeller (31) being rotationally driven by said low-pressure shaft and the second propeller being rotationally driven by an electric motor (70), the second propeller (32) being further disposed at a distance between 1.5 and 4 cord lengths (LC1) from the first propeller (31) defined between the respective axes of shimming (A31, A32) of each of the first and second propellers.

A gas turbine engine having an interdigitated turbine assembly including a first turbine rotor and a second turbine rotor, wherein a total number of stages at the interdigitated turbine assembly is between 3 and 8, and an average stage pressure ratio at the interdigitated turbine assembly is between 1.3 and 1.9. A gear assembly is configured to receive power from the interdigitated turbine assembly, and a fan assembly is configured to receive power from the gear assembly. The interdigitated turbine assembly and the gear assembly are together configured to allow the second turbine rotor to rotate at a second rotational speed greater than a first rotational speed at the first turbine rotor. The fan assembly and the gear assembly are together configured to allow the fan assembly to rotate at a third rotational speed less than the first rotational speed and the second rotational speed. The interdigitated turbine assembly, the gear assembly, and the fan assembly together have a maximum AN.sup.2 at the second turbine rotor between 30 and 90.

A gas turbine engine having an interdigitated turbine assembly including a first turbine rotor and a second turbine rotor, wherein a total number of stages at the interdigitated turbine assembly is between 3 and 8, and an average stage pressure ratio at the interdigitated turbine assembly is between 1.3 and 1.9. A gear assembly is configured to receive power from the interdigitated turbine assembly, and a fan assembly is configured to receive power from the gear assembly. The interdigitated turbine assembly and the gear assembly are together configured to allow the second turbine rotor to rotate at a second rotational speed greater than a first rotational speed at the first turbine rotor. The fan assembly and the gear assembly are together configured to allow the fan assembly to rotate at a third rotational speed less than the first rotational speed and the second rotational speed. The interdigitated turbine assembly, the gear assembly, and the fan assembly together have a maximum AN.sup.2 at the second turbine rotor between 30 and 90.

An engine assembly includes an engine including a component and defining an opening and an interior, the component including a first side and an opposite second side, the second side positioned within the interior of the engine. The engine assembly also includes an inspection tool having a first member including at least one of a receiver or a transmitter and directed at the first side of the component. The inspection tool also includes a second member including the other of the receiver or the transmitter and positioned at least partially within the interior of the engine and directed at the second side of the component to communicate a signal with the first member through the component, the second member being a robotic arm extending through the opening of the engine.

An engine assembly includes an engine including a component and defining an opening and an interior, the component including a first side and an opposite second side, the second side positioned within the interior of the engine. The engine assembly also includes an inspection tool having a first member including at least one of a receiver or a transmitter and directed at the first side of the component. The inspection tool also includes a second member including the other of the receiver or the transmitter and positioned at least partially within the interior of the engine and directed at the second side of the component to communicate a signal with the first member through the component, the second member being a robotic arm extending through the opening of the engine.

Counter-rotating turbine of a turbomachine extending about an axis of rotation and comprising an inner rotor rotating about the axis of rotation, and comprising at least one inner movable blade rotatably supported by a first shaft, an outer rotor rotating about the axis of rotation in a direction opposite to the inner rotor, and comprising at least one outer movable blade rotatably supported by a second shaft coaxial with the first shaft, the first and second shafts extending axially from upstream to downstream of the turbine, wherein the first shaft is guided in rotation by a first bearing disposed between the first shaft and an upstream casing of the turbine, and the second shaft is guided in rotation by a second bearing disposed between the second shaft and said upstream casing of the turbine.