In one exemplary embodiment, a gas turbine engine includes a bypass flow ratio greater than about ten. A fan supported on a fan shaft having a plurality of fan blades and a low fan pressure ratio of less than 1.45 measured across the fan blades alone. A gutter with an annular channel. A gear system connected to the fan shaft having a gear reduction ratio greater than 2.5, planetary gears, and a ring gear with an aperture that is axially aligned with the annular channel. A torque frame at least partially supports the gear system. A low pressure turbine with an inlet, an outlet, and a low pressure turbine pressure ratio greater than 5:1.

A turbine engine has a fan shaft. At least one tapered bearing is mounted on the fan shaft. The fan shaft includes at least one passage extending in a direction having at least a radial component, and adjacent the at least one tapered bearing. A fan is mounted for rotation on the tapered bearing. An epicyclic gear train is coupled to drive the fan. The epicyclic gear train includes a carrier supporting intermediate gears that mesh with a sun gear. A ring gear surrounds and meshes with the intermediate gears. Each of the intermediate gears are supported on a respective journal bearing. The epicyclic gear train defines a gear reduction ratio of greater than or equal to about 2.3. A turbine section is coupled to drive the fan through the epicyclic gear train. The turbine section has a fan drive turbine that includes a pressure ratio that is greater than about 5. The fan includes a pressure ratio that is less than about 1.45, and the fan has a bypass ratio of greater than about ten (10).

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 is provided for determining the diameter of a rotor of a turbomachine, rotor being equipped with rotor blades. The method involves setting the rotor with the rotor blade ring in rotation, arranging a clearance measuring device assigned to the rotor blade ring outside the region of the latter, measuring the distance to the rotor blades of the rotor blade ring which are rotating past the clearance measuring device, and using the measured distance for determining the diameter of the rotor. During measuring, the rotational speed is identical to, almost identical to or higher than the setpoint rotational speed of the rotor.

A turbomachine is made by first providing a stepped shaft having a large-diameter cylindrical portion, an intermediate-diameter cylindrical portion, and a small-diameter cylindrical portion all centered on a common axis. A separately manufactured a one-piece and annular first impeller wheel is then permanently mounted on the large-diameter portion with a back face of the first wheel facing axially toward the intermediate-diameter portion and carrying a rotor bearing half of an axial magnetic bearing. A rotor ring of a radial bearing is then detachably mounted on the intermediate-diameter portion of the shaft, and finally a one-piece and annular second impeller wheel is detachably mounted on the small-diameter portion of the shaft with a back face of the second wheel facing axially toward the first wheel and carrying a rotor bearing half of another axial magnetic bearing.

A gas turbine engine according to an example of the present disclosure includes a propulsor section including a propulsor supported on a propulsor shaft, a turbine section including a turbine shaft, a compressor section having a plurality of compressor hubs with blades driven by the turbine shaft about an engine axis, and an epicyclic gear train interconnecting the propulsor shaft and the turbine shaft. The epicyclic gear train includes a sun gear coupled to the turbine shaft, intermediary gears arranged circumferentially about and meshing with the sun gear, a carrier and a ring gear including first and second portions. The first and second portions have axially opposed faces abutting one another at a radial interface.

In one exemplary embodiment, an epicyclic gear train for a turbine engine includes a first shaft that is rotatable about an axis. A ring gear includes first and second portions each having an inner periphery with teeth. The first and second portions are secured to one another at a radial interface. At least one of the first and second portions includes a flange that extends radially outward. The flange is fixed to the first shaft in an axial direction by a fastening element. A carrier supports star gears that mesh with the ring gear. A sun gear meshes with the star gears and is coupled to a second shaft.

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.

An unbalanced rotor is provided to perform unbalance testing on an aircraft power plant. The unbalanced rotor includes a hollow body rotatable about a rotation axis and an unbalancing weight installed inside of the hollow body. The unbalancing weight is installed inside of the hollow body to intentionally vibrate the rotor during rotation of the rotor. The unbalancing weight is fastened to the hollow body via one or more fasteners. A portion of the unbalancing weight is disposed radially inwardly of a retainer of the hollow body and is engaged with the retainer to define a radial load path between the unbalancing weight and the hollow body via the retainer. The radial load path excludes the one or more fasteners.

A gas turbine engine according to an example of the present disclosure includes a propulsor section including a propulsor supported on a propulsor shaft, a turbine section including a turbine shaft, a compressor section having a plurality of compressor hubs with blades driven by the turbine shaft about an engine axis, and an epicyclic gear train interconnecting the propulsor shaft and the turbine shaft. The epicyclic gear train includes a sun gear coupled to the turbine shaft, intermediary gears arranged circumferentially about and meshing with the sun gear, a carrier and a ring gear including first and second portions. The first and second portions have axially opposed faces abutting one another at a radial interface.