Abstract: A method of operating a gas turbine engine in a multi-engine aircraft, the gas turbine engine having an engine shaft mounted for rotation in a bearing and a gearbox connected to the engine shaft for torque transmission therebetween, includes axially preloading the bearing using an axially biasing element disposed between the gas turbine engine and the gearbox. The axially biasing element reacts against the gearbox to exert an axial preload force on the bearing and the engine shaft of the gas turbine engine.

Abstract: A method of operating a gas turbine engine in a multi-engine aircraft, the gas turbine engine having an engine shaft mounted for rotation in a bearing and a gearbox connected to the engine shaft for torque transmission therebetween, includes axially preloading the bearing using an axially biasing element disposed between the gas turbine engine and the gearbox. The axially biasing element reacts against the gearbox to exert an axial preload force on the bearing and the engine shaft of the gas turbine engine.

Abstract: A gear comprises gear teeth. An annular web has the gear teeth on an external surface thereof and rotatable about a rotational axis of the gear. The web comprises a wall having at least a first axial surface and a second axial surface on the opposite side of the wall. The web defined by a first web section in which the first axial surface, in an inward direction, inclines away from a radial plane to which the rotational axis is normal, a second web section radially inward of the first web section, and in which the first axial surface, in the inward direction, inclines toward said radial plane.

Abstract: A seal arrangement for a gas turbine engine includes a seal runner having a sealing lip extending radially outwardly from a root portion to a tip portion. A static seal is mounted in axially opposed facing relationship to the sealing lip. The static seal and the sealing lip define an axial gap therebetween. A point of flexion is provided in the root portion to allow the sealing lip to flex relative to the axial gap under centrifugal loads, and wherein a center of gravity of the sealing lip is disposed radially outwardly from the point of flexion by a first predetermined amount and axially offset from the point of flexion by a second predetermined amount. The first and second predetermined amounts are selected to modulate the centrifugal flexion of the sealing lip so as to compensate at least partially for thermally induced deformation of the sealing lip.

Abstract: A seal arrangement for a gas turbine engine includes a seal runner having a sealing lip extending radially outwardly from a root portion to a tip portion. A static seal is mounted in axially opposed facing relationship to the sealing lip. The static seal and the sealing lip define an axial gap therebetween. A point of flexion is provided in the root portion to allow the sealing lip to flex relative to the axial gap under centrifugal loads, and wherein a center of gravity of the sealing lip is disposed radially outwardly from the point of flexion by a first predetermined amount and axially offset from the point of flexion by a second predetermined amount.

Abstract: A gear comprises gear teeth. An annular web has the gear teeth on an external surface thereof and rotatable about a rotational axis of the gear. The web comprises a wall having at least a first axial surface and a second axial surface on the opposite side of the wall. The web defined by a first web section in which the first axial surface, in an inward direction, inclines away from a radial plane to which the rotational axis is normal, a second web section radially inward of the first web section, and in which the first axial surface, in the inward direction, inclines toward said radial plane.

Abstract: A fan and shaft assembly for a turbofan gas turbine engine comprises a shaft and a fan. Sets of aligned throughbores are respectively of the shaft and the fan, at a junction between the shaft and the fan. Fastening systems are provided for the sets of aligned throughbores. Each fastening system comprises a sleeve received in one of the sets of aligned throughbores and sized to fit without play in the set of aligned throughbores. A head of the sleeve abuts a surface at the junction between the shaft and the fan. A fastener is inserted in the sleeve and extends beyond both ends of the sleeve to clamp the fan to the shaft, the fastener being loosely received in the sleeve. A method for replacing a component of a fastening system retaining a fan to a shaft is provided as well.

Abstract: A fan and shaft assembly for a turbofan gas turbine engine comprises a shaft and a fan. Sets of aligned throughbores are respectively of the shaft and the fan, at a junction between the shaft and the fan. Fastening systems are provided for the sets of aligned throughbores. Each fastening system comprises a sleeve received in one of the sets of aligned throughbores and sized to fit without play in the set of aligned throughbores. A head of the sleeve abuts a surface at the junction between the shaft and the fan. A fastener is inserted in the sleeve and extends beyond both ends of the sleeve to clamp the fan to the shaft, the fastener being loosely received in the sleeve. A method for replacing a component of a fastening system retaining a fan to a shaft is provided as well.

Abstract: A sealing collar is provided on a body in which the body has a cylindrical wall on which a hole emerges and a fluid situated in the body is able to escape through the hole. The sealing collar includes a fixing band entirely surrounding the cylindrical wall. The fixing band has a sealing portion to sealedly obturate the hole and a means for closing and tightening the fixing band. The fixing band is provided with at least one claw extending in the direction of the cylindrical wall so that on closing and tightening of the fixing band around the cylindrical wall, the hole is sealedly obturated and the claw is pressed against the cylindrical wall and contributes to immobilizing the sealing collar on the body.

Abstract: A turbine rotor for a gas turbine engine including a disc having a hub defining a central bore for receiving an engine shaft. A nut retains the disc on the shaft. The disc retaining nut has at least one cooling passage defined therein and disposed for directing a flow of cooling air passing through the bore of the disc.

Abstract: A turbine rotor for a gas turbine engine comprises a disc having a hub defining a central bore for receiving an engine shaft. A nut retains the disc on the shaft. The disc retaining nut has at least one cooling passage defined therein and disposed for directing a flow of cooling air passing through the bore of the disc.