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 turbine includes a first rotor and a second rotor that can rotate in opposite directions and are interleaved. The turbine further includes a ring to which abradable material is secured, the ring, unsegmented, extending between the first impellers of the first rotor and the second rotor, over a sector of between 350 and 360°, and, axially between an upstream end and a downstream end of the ring, the ring is held with the second rotor.

A dual pump unit having a pair of pumps that provide parallel hydraulic paths, and are configured to operate concurrently in opposite rotational directions. The dual pump unit has a sealed casing which includes a suction flange, two volutes in hydraulically parallel configuration, and a discharge flange. The pair of pumps are located within a respective volute of the casing and, in an example, are radially inline and horizontally inline. The casing may include a flattened bottom. Each pump may include a touchscreen for configuration of the respective pump. The pumps are controllable to circulate a circulating medium to collectively provide output to source a load.

An assembly for an aircraft propulsion system is provided, the assembly having an axial centerline. The assembly comprises a fixed structure, a first thrust reverser door, and a second thrust reverser door. The first thrust reverser door being pivotally attached to the fixed structure along a first pivot axis, and the second thrust reverser door being pivotally attached to the fixed structure along a second pivot axis. The first pivot axis and the second pivot axis are both radially located at a first distance from the assembly axial centerline. The first pivot axis is located at a first axial position, and the second pivot axis is located at a second axial position. The second axial position is displaced from the first axial position.

A dual pump unit having a pair of pumps that provide parallel hydraulic paths, and are configured to operate concurrently in opposite rotational directions. The dual pump unit has a sealed casing which includes a suction flange, two volutes in hydraulically parallel configuration, and a discharge flange. The pair of pumps are located within a respective volute of the casing and, in an example, are radially inline and horizontally inline. The casing may include a flattened bottom. Each pump may include a touchscreen for configuration of the respective pump. The pumps are controllable to circulate a circulating medium to collectively provide output to source a load.

A turbine has a first rotor and a second rotor configured to pivot about a longitudinal axis (X) according to two opposite directions of rotation. The first rotor has a radially outer drum from which bladesextend radially inwards. The first rotorand the second rotor are surrounded by a stator annular part. The stator annular partdelimits, with the drum, at least one upstream annular cavityand one downstream annular cavityseparated from each other by sealing means.

A turbine for a turbomachine has a first rotor and a second rotor configured to pivot about an axis in two opposite directions of rotation. The first rotor includes a radially outer drum from which blades extend radially inwards. The turbine has cooling means attached relative to the outer drum. The cooling means include a support plate with at least one first orifice and a calibration plate that is attached to the support plate and located radially inside the support plate. The calibration plate has at least one second calibration orifice facing the outer drum to allow the passage of cooling air radially from the outside to the inside through the first and second orifices.

A turbine for a turbomachine has a first rotor and a second rotor configured to pivot about an axis in two opposite directions of rotation. The first rotor includes a radially outer drum from which blades extend radially inwards. The turbine has cooling means attached relative to the outer drum. The cooling means include a support plate with at least one first orifice and a calibration plate that is attached to the support plate and located radially inside the support plate. The calibration plate has at least one second calibration orifice facing the outer drum to allow the passage of cooling air radially from the outside to the inside through the first and second orifices.

A turbomachine includes a rotatable annular outer drum rotor connected to a first plurality of blades. The rotatable annular outer drum rotor is constructed of, at least, a first drum segment and a second drum segment. The turbomachine further includes a retaining ring arranged and secured between the first and second drum segments of the rotatable annular outer drum rotor for radially retaining each of the first plurality of blades via their respective blade root portions within the rotatable annular outer drum rotor.

Aircraft turbomachine with mechanical reducer and counter-rotating turbine are described. The turbomachine includes a fan driven in rotation by a fan shaft, a mechanical reducer with epicyclic gear train, a gas generator comprising a counter-rotating turbine, a first turbine shaft of which is coupled to an input shaft of the reducer and to a pin, and a second turbine shaft of which is coupled to the fan shaft. The guidance of the reducer input shaft is provided by a first ball bearing, the guidance of the pin is provided by a second roller bearing, and the guidance of the first shaft is provided by a third roller bearing axially interposed between the first and second bearings.