Turbomachine (10) having a contrarotating turbine for aircraft, the turbomachine comprising a contrarotating turbine (22) of which a first rotor (22a) is configured to rotate in a first direction of rotation and is connected to a first turbine shaft (36), and a second rotor (22b) is configured to rotate in an opposite direction of rotation and is connected to a second turbine shaft (38), the first rotor comprising turbine discs that are interleaved between turbine discs of the second rotor, said first shaft (36) being guided by at least two guide bearings (60, 62) mounted between this first shaft and a stator casing, and said second shaft (38) being guided by at least two guide bearings (56, 58) mounted between this second shaft and another stator casing (28).

Disclosed is a turbo machine (10) with counter-rotating turbine for an aircraft, comprising: - a high-pressure body, - a low-pressure counter-rotating turbine (22), - a planetary-type mechanical epicyclic reduction gear (42), - guide bearings (56-62) for the turbine shafts (36, 38), characterised in that said reduction gear (42) and certain of the bearings (60, 62) are housed in a lubrication chamber (86) supplied with oil and comprising dynamic seals (86a-86d), and in that the turbo machine comprises circuits (C1, C2) for pressurising these seals.

A carrier assembly has a pair of axially spaced-apart plates defining an axial gap therebetween. The plates have a plurality of planetary bores on a plurality of planetary axes. A plurality of planetary gear mount assemblies are disposed on the planetary axes and mounted within the planetary bores of the gear carrier. Each assembly comprises a journal bearing shaft having a pair of compliance grooves extending axially from opposed axial ends of the shaft. An inner cylindrical surface of each compliance groove defines a shaft mounting surface. A pair of collars is provided to assemble each journal bearing shaft to the carrier. Each collar has a mounting socket mating the shaft mounting surface and an external collar surface matching the planetary bore diameter.

A gas turbine engine typically includes a fan section, a compressor section, a combustor section and a turbine section. A speed reduction device such as an epicyclical gear assembly may be utilized to drive the fan section such that the fan section may rotate at a speed different than the turbine section so as to increase the overall propulsive efficiency of the engine. In such engine architectures, a shaft driven by one of the turbine sections provides an input to the epicyclical gear assembly that drives the fan section at a speed different than the turbine section such that both the turbine section and the fan section can rotate at closer to optimal speeds providing increased performance attributes and performance by desirable combinations of the disclosed features of the various components of the described and disclosed gas turbine engine.

A carrier structure for an epicyclic gear drive is provided. The carrier structure includes carrier elements connected with at least one planet gear and the first carrier element is connected with the second carrier element through at least two struts with the at least two struts having an inclination angle of more than 20° in the direction of a rotation around a rotation axis of the carrier structure.

A gas turbine engine comprises a gearbox comprising a sun gear, an annulus gear, a plurality of planet gears and a planet gear carrier. The sun gear meshes with the planet gears and the planet gears mesh with the annulus gear. Each planet gear is rotatably mounted in the planet gear carrier. The planet gear carrier comprises a plurality of axles arranged parallel to the axis of the gearbox. The axially spaced ends of each axle are secured to the planet gear carrier. Each planet gear is rotatably mounted on a corresponding one of the axles by a bearing arrangement. Each bearing arrangement comprises a journal bearing and a rolling element bearing and each planet gear is rotatably mounted on a journal bearing and each journal bearing is rotatably mounted on an axle by at least one rolling element bearing.

An epicyclic gear train for a turbine engine includes a gutter with an annular channel. A rotating structure includes a ring gear that has an aperture that is axially aligned with the annular channel. Axially spaced apart walls extend radially outward relative to the rotating structure to define a passageway. The passageway is arranged radially between and axially aligned with the aperture and the annular channel. The walls are configured to inhibit an axial flow of an oil passing from the aperture toward the annular channel.

A method of designing a turbofan engine according to an exemplary aspect of the present disclosure includes, among other things, providing a fan section including a plurality of fan blades, providing a low pressure turbine driving the plurality of fan blades through a gear train, providing a fan nacelle and a core nacelle, the fan nacelle at least partially surrounding the core nacelle, providing a fan bypass flow path defined between the core nacelle and the fan nacelle, and providing a fan variable area nozzle in communication with the fan bypass flow path and defining a fan nozzle exit area between the fan nacelle and the core nacelle.

A gas turbine engine comprises a gearbox comprising a sun gear, an annulus gear, a plurality of planet gears and a carrier. The carrier comprises a primary structure and at least one reinforcing structure. The primary structure comprises a first material and the at least one reinforcing structure comprises a second material. The primary structure includes a first ring, a second ring spaced axially from the first ring and a plurality of circumferentially spaced axles extending axially between the first ring and the second ring. Each planet gear is rotatably mounted on a respective one of the axles by a bearing. The reinforcing structure is secured to the primary structure and the reinforcing structure comprises a particulate reinforced material or a fibre reinforced material. The reinforcing structure increases the stiffness of the carrier and reduces the weight of the carrier.

According to an aspect, a system for a gas turbine engine includes a reduction gear train operable to drive rotation of a starter gear train that interfaces to an accessory gearbox of the gas turbine engine. The reduction gear train includes a starter interface gear that engages the starter gear train and a core-turning clutch operably connected to the starter interface gear. The reduction gear train also includes a geared rotary actuator including a primary planetary gear system, where the geared rotary actuator is operably connected to the core-turning clutch. The reduction gear train further includes a secondary planetary gear system operably connected to the primary planetary gear system and a core-turning input. The system also includes a mounting pad with an interface to couple a core-turning motor to the core-turning input of the reduction gear train.