A gas turbine engine configured with an engine core. A fan located upstream of the engine core, the fan comprising a plurality of fan blades; and a gearbox arranged to receive an input from the core shaft and to output drive to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox being an epicyclic gearbox comprising a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted, the planet carrier having an effective linear torsional stiffness and the gearbox having a gear mesh stiffness between the planet gears and the ring gear. Additionally, the product of the effective linear torsional stiffness of the planet carrier and the gear mesh stiffness between the planet gears and the ring gear is greater than or equal to 5.0×10.sup.18 N.sup.2m.sup.−2.

A gas turbine engine for an aircraft configured with an engine core that has a turbine, a compressor, and a core shaft connecting the turbine to the compressor. A fan located upstream of the engine core, that has a plurality of fan blades. A gearbox arranged to receive an input from the core shaft and to output to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox being an epicyclic gearbox having a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The gearbox having an overall gear mesh stiffness, and wherein the overall gear mesh stiffness of the gearbox is greater than or equal to 1.05×10.sup.9 N/m and less than or equal to 8.0×10.sup.9 N/m.

A turbomachine engine includes a fan assembly and a core engine comprising a turbine and an input shaft rotatable with the turbine is provided. A single-stage epicyclic gear assembly receives the input shaft at a first speed and drives an output shaft coupled to the fan assembly at a second speed. A sun gear rotates about a longitudinal centerline of the gear assembly and has a sun gear-mesh region along the longitudinal centerline of the gear assembly where the sun gear is configured to contact a plurality of planet gears. A ring gear-mesh region is provided along the longitudinal centerline of the gear assembly where a ring gear is configured to contact the plurality of planet gears. The sun gear-mesh region is axially offset from the ring gear-mesh region along the longitudinal centerline.

A method for manufacturing a mechanical reducer for an aircraft turbomachine including a central pinion, an outer crown, N planet pinions, where N≥3, each planet pinion including a first stage meshing with the central pinion, and a second stage meshing with the outer crown, the method including the assembly marking, wherein N teeth of the central pinion are marked, and N pairs of teeth of the first stage of each planet pinion are marked, the N planet pinions each being marked identically, and the assembly of the mechanical reducer, so that the teeth of the pairs of marked teeth of the first stage of each planet pinion are disposed on either side of a marked tooth of the central pinion.

A turbomachine engine includes a fan assembly and a core engine comprising a turbine and an input shaft rotatable with the turbine is provided. A single-stage epicyclic gear assembly receives the input shaft at a first speed and drives an output shaft coupled to the fan assembly at a second speed. A sun gear rotates about a longitudinal centerline of the gear assembly and has a sun gear-mesh region along the longitudinal centerline of the gear assembly where the sun gear is configured to contact a plurality of planet gears. A ring gear-mesh region is provided along the longitudinal centerline of the gear assembly where a ring gear is configured to contact the plurality of planet gears. The sun gear-mesh region is axially offset from the ring gear-mesh region along the longitudinal centerline.

A gas turbine engine configured with an engine core. A fan located upstream of the engine core, the fan comprising a plurality of fan blades; and a gearbox arranged to receive an input from the core shaft and to output drive to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox being an epicyclic gearbox comprising a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted, the planet carrier having an effective linear torsional stiffness and the gearbox having a gear mesh stiffness between the planet gears and the ring gear. Additionally, the product of the effective linear torsional stiffness of the planet carrier and the gear mesh stiffness between the planet gears and the ring gear is greater than or equal to 5.0×10.sup.18N.sup.2m.sup.−2.

A planetary gear for a planetary gearset has a gear body and a planetary gear shaft defining a planetary gear rotational axis (APR) of the planetary gear. The gear body includes a gear rim having a first number (n1) of teeth and a second number (n2) of ribs. The ribs extend between the planetary gear shaft and the gear rim, and planetary gear contact projections are arranged on the ribs and project beyond the gear rim along the planetary gear rotational axis (APR). Also disclosed is a planet carrier for such a planetary gear, including an insert for removing torque from the carrier body, which insert is connected to the first disk-shaped body. The first disk-shaped body forms a first free planet carrier face on which a number of reinforcing ribs are arranged.

An epicyclic gear assembly includes a carrier that includes a first plate axially spaced from a second plate. At least one epicyclic gear set is located between the first plate and the second plate. The first plate is configured to rotate with an output of the epicyclic gear assembly. A first bearing race is attached to the first plate for supporting a first bearing. A second bearing race is attached to the second plate for supporting a second bearing.

A method for manufacturing a mechanical reducer for an aircraft turbomachine including a central pinion, an outer crown, N planet pinions, where N≥3, each planet pinion including a first stage meshing with the central pinion, and a second stage meshing with the outer crown, the method including the assembly marking, wherein N teeth of the central pinion are marked, and N pairs of teeth of the first stage of each planet pinion are marked, the N planet pinions each being marked identically, and the assembly of the mechanical reducer, so that the teeth of the pairs of marked teeth of the first stage of each planet pinion are disposed on either side of a marked tooth of the central pinion.

A gas turbine engine for an aircraft configured with an engine core that has a turbine, a compressor, and a core shaft connecting the turbine to the compressor. A fan located upstream of the engine core, that has a plurality of fan blades. A gearbox arranged to receive an input from the core shaft and to output to the fan so as to drive the fan at a lower rotational speed than the core shaft. The gearbox being an epicyclic gearbox having a sun gear, a plurality of planet gears, a ring gear, and a planet carrier on which the planet gears are mounted. The gearbox having an overall gear mesh stiffness, and wherein the overall gear mesh stiffness of the gearbox is greater than or equal to 1.05×10.sup.9 N/m and less than or equal to 8.0×10.sup.9 N/m.