Mounting system and mounting method for gas turbine aero engine

1. A system for mounting a gas turbine engine to a pylon on a wing of an aircraft, the pylon having a forward pylon mount and a rearward pylon mount, the gas turbine engine having a forward engine mount for service attachment to the forward pylon mount and a rearward engine mount for service attachment to the rearward pylon mount,

the system comprising at least one temporary forward link, being length-adjustable, and at least one temporary rearward link, being length-adjustable, for temporarily attaching the gas turbine engine to the pylon via the temporary forward link and the temporary rearward link, wherein the at least one temporary forward link and the at least one temporary rearward link each including:

a hoisting arm including a respective winch, a respective pulley located at a distal end of the hoisting arm, and a respective tension member that extends from the respective winch and over the respective pulley and that is removably coupled to a respective engine mount, the respective winch operable to adjust pay out of the respective tension member thereby to provide length adjustment of the respective tension member, the at least one temporary forward link and the at least one temporary rearward link being operable to maintain a positional relationship between the gas turbine engine and the pylon in the absence of adjustment of the lengths of the respective tension member of the at least one temporary forward link and the at least one temporary rearward link,

wherein:

the hoisting arm, the respective winch, and the respective pulley of the at least one temporary forward link are removably mounted on an upwardly facing surface of the pylon;

the system provides a positional relationship between the gas turbine engine and the pylon such that the forward engine mount is out of alignment with the forward pylon mount and/or the rearward engine mount is out of alignment with the rearward pylon mount,

adjustment of the length of the respective tension member of at least one of the at least one temporary forward link and the at least one temporary rearward link is operable to bring the forward engine mount into alignment with the forward pylon mount and/or the rearward engine mount into alignment with the rearward pylon mount for service attachment of the gas turbine engine to the pylon, and

the at least one temporary forward link and the at least one temporary rearward link are removable from the gas turbine engine and from the pylon.

2. The system of claim 1 wherein the at least one temporary rearward link includes exactly two temporary rearward links, and wherein the hoisting arm of a first temporary rearward link of the two temporary rearward links is disposed on and extends away from a first lateral side of the pylon with respect to the forwards-rearwards direction of the aircraft and engine, and the hoisting arm of a second temporary rearward link of the two temporary rearward links is disposed on and extends away from a second lateral side of the pylon located opposite the first lateral side.

3. The system of claim 1 wherein the at least one temporary forward link includes exactly one temporary forward link, disposed on the upwardly facing surface of the pylon at a forward end of the pylon.

4. The system of claim 3 wherein the respective winch and the respective pulley of the temporary forward link are disposed on the pylon above a central axis of the engine such that the respective tension member is aligned with the central axis.

5. The system of claim 1 wherein, for service attachment of the gas turbine engine to the pylon, the forward engine mount attaches to the forward pylon mount via at least one mounting pin extending through corresponding mounting pin apertures in the forward engine mount and the forward pylon mount.

6. The system of claim 1 wherein the gas turbine engine is a core mounted gas turbine engine.

7. The system of claim 1 wherein each respective winch is a variable speed winch.

8. A method for mounting a gas turbine engine to a pylon on a wing of an aircraft, the pylon having a forward pylon mount and a rearward pylon mount, the gas turbine engine having a forward engine mount for service attachment to the forward pylon mount and a rearward engine mount for service attachment to the rearward pylon mount, the method comprising:

providing at least one temporary forward link, being length-adjustable, and at least one temporary rearward link, being length-adjustable, the at least one temporary forward link and the at least one temporary rearward link each including a hoisting arm including a respective winch, a respective pulley located at a distal end of the hoisting arm, and a respective tension member that extends from the respective winch and over the respective pulley and that is removably coupled to a respective engine mount, the respective winch operable to adjust pay out of the respective tension member thereby to provide length adjustment of the respective tension member, wherein the hoisting arm, the respective winch, and the respective pulley of the at least one temporary forward link are removably mounted on an upwardly facing surface of the pylon,

presenting the gas turbine engine to the pylon, in a state in which the forward engine mount is out of alignment with the forward pylon mount and/or the rearward engine mount is out of alignment with the rearward pylon mount,

temporarily attaching the gas turbine engine to the pylon via the at least one temporary forward link and the at least one temporary rearward link, the at least one temporary forward link and the at least one temporary rearward link being operable to maintain a positional relationship between the gas turbine engine and the pylon in the absence of adjustment of the lengths of the at least one temporary forward link and the at least one temporary rearward link,

adjusting the length of the respective tension member of at least one of the at least one temporary forward link and the at least one temporary rearward link to bring the forward engine mount into alignment with the forward pylon mount and/or the rearward engine mount into alignment with the rearward pylon mount for service attachment of the gas turbine engine to the pylon,

conducting service attachment of the gas turbine engine to the pylon,

removing the at least one temporary forward link and the at least one temporary rearward link.

9. An aircraft in a state in which a gas turbine engine is temporarily mounted to a pylon on a wing of the aircraft, the pylon having a forward pylon mount and a rearward pylon mount, the gas turbine engine having a forward engine mount for service attachment to the forward pylon mount and a rearward engine mount for service attachment to the rearward pylon mount, a positional relationship between the gas turbine engine and the pylon being such that the forward engine mount is out of alignment with the forward pylon mount and/or the rearward engine mount is out of alignment with the rearward pylon mount,

the aircraft further comprising at least one temporary forward link, being length-adjustable, and at least one temporary rearward link, being length-adjustable, the gas turbine engine being temporarily attached to the pylon via the at least one temporary forward link and the at least one temporary rearward link, wherein the at least one temporary forward link and the at least one temporary rearward link each include a hoisting arm including a respective winch, a respective pulley located at a distal end of the hoisting arm, and a respective tension member that extends from the respective winch and over the respective pulley and that is removably coupled to a respective engine mount, the respective winch operable to adjust pay out of the respective tension member thereby to provide length adjustment of the respective tension member, the at least one temporary forward link and the at least one temporary rearward link being operable maintain the positional relationship between the gas turbine engine and the pylon in the absence of adjustment of the lengths of the respective tension member of the at least one temporary forward link and the at least one temporary rearward link,

wherein:

the hoisting arm, the respective winch, and the respective pulley of the at least one temporary forward link are removably mounted on an upwardly facing surface of the pylon;

adjustment of the length of the respective tension member of at least one of the at least one temporary forward link and the temporary rearward link is operable to bring the forward engine mount into alignment with the forward pylon mount and/or the rearward engine mount into alignment with the rearward pylon mount for service attachment of the gas turbine engine to the pylon, and

the at least one temporary forward link and the at least one temporary rearward link are removable from the gas turbine engine and from the pylon.

10. The aircraft of claim 9 wherein the gas turbine engine further comprises: an engine core comprising a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan located upstream of the engine core, the fan comprising a plurality of fan blades; and a gearbox that receives an input from the core shaft and outputs drive to the fan so as to drive the fan at a lower rotational speed than the core shaft.

11. The aircraft of claim 10 wherein: the turbine is a first turbine, the compressor is a first compressor, and the core shaft is a first core shaft; the engine core further comprises a second turbine, a second compressor, and a second core shaft connecting the second turbine to the second compressor; and the second turbine, second compressor, and second core shaft are arranged to rotate at a higher rotational speed than the first core shaft.

12. The system of claim 3 wherein the temporary forward link further includes a forward mount bracket arranged on an axially facing forward end face of the pylon, and wherein the forward pylon mount includes a first mounting arm and a second mounting arm that each extend from the forward mount bracket.

13. The system of claim 12 wherein the forward mount bracket includes at least one access slot formed therein, and wherein the respective tension member extends from pulley, through the at least one access slot, and couples to the forward engine mount.

14. The aircraft of claim 9 wherein the at least one temporary rearward link includes exactly two temporary rearward links, and wherein the hoisting arm of a first temporary rearward link of the two temporary rearward links is disposed on and extends away from a first lateral side of the pylon with respect to the forwards-rearwards direction of the aircraft and engine, and the hoisting arm of a second temporary rearward link of the two temporary rearward links is disposed on and extends away from a second lateral side of the pylon located opposite the first lateral side.

15. The aircraft of claim 9 wherein the at least one temporary forward link includes exactly one temporary forward link, disposed on the upwardly facing surface of the pylon at a forward end of the pylon.

16. The aircraft of claim 15 wherein the respective winch and the respective pulley of the temporary forward link are disposed on the pylon above a central axis of the engine such that the respective tension member is aligned with the central axis.

17. The aircraft of claim 9 wherein, for service attachment of the gas turbine engine to the pylon, the forward engine mount attaches to the forward pylon mount via at least one mounting pin extending through corresponding mounting pin apertures in the forward engine mount and the forward pylon mount.

18. The aircraft of claim 15 wherein the temporary forward link further includes a forward mount bracket arranged on an axially facing forward end face of the pylon, and wherein the forward pylon mount includes a first mounting arm and a second mounting arm that each extend from the forward mount bracket.

19. The aircraft of claim 18 wherein the forward mount bracket includes at least one access slot formed therein, and wherein the respective tension member extends from pulley, through the at least one access slot, and couples to the forward engine mount.