GB2168299A

GB2168299A - Aircraft structure with gas turbine engine and thrust reverser

Info

Publication number: GB2168299A
Application number: GB08431557A
Authority: GB
Inventors: Arnold Charles Newton
Original assignee: Rolls Royce PLC
Current assignee: Rolls Royce PLC
Priority date: 1984-12-13
Filing date: 1984-12-13
Publication date: 1986-06-18

Abstract

A gas turbine engine (12) is mounted from and forwardly of an aircraft wing (10) such that its nozzle (16) lies just under the wing. The nozzle is tiltable upwards and the wing has an exposable aperture (20) therethrough. Thus when the aperture is exposed and the nozzle tilted upwards, the engine may continue running and the efflux passes through the wing. Flaps (24, 26) on the wing may be positioned so as to enhance the effect of the upwards attitude of the nozzle. The arrangement is used to obtain reverse thrust following touchdown of an aircraft having the arrangement. <IMAGE>

Description

SPECIFICATION Aircraft structure with gas turbine engine and thrust reverser The present invention discloses, in combination, an aircraft structure having exhaust flow directing means, a gas turbine engine supported by the wing and including a thrust directing nozzle.

The invention will now be described, by way of example and with reference to the accompanying drawings in which: Figure 1 depicts one embodiment of the inventive combination and Figure 2 depicts a further embodiment of the inventive combination.

In Figure 1, an aircraft wing 10 supports a gas turbine engine 12 via a pylon 14.

The pylon 14 extends forwardly of the wing 10 so that the exhaust nozzle 16 of the gas turbine 12 is positioned in the vicinity of the leading edge 18 of the wing 10.

An aperture 20 is provided in the casing 10 and is positioned in line with the gas turbine engine 12, and downstream thereof. A member of elongate, aerofoil section cascades 22 are fixed in the aperture 20 and extend spanwise of the wing 10. Only two such cascades are shown in Figure 1, but any suitable number could be utilised.

When an associated aircraft (not shown) takes off, cruises and descends, the aperture is closed by doors 24 and 26, so as to provide a smooth wing outer surface.

The gas turbine engine 12 is enclosed in a streamlined cowl 30 and the downwstream end portion of both cowl 30 and the jet pipe 32 of the gas turbine engine 12 are scarfed in a common plane 34.

The jet pipe 32 and the cowl 30 are bulged (not shown) in the area which includes the scarf, so as to enable them to be circular in the plane of the scarfe.

The cowl portion 30a which is downstream of the scarfe plane 34 is fixed to the nozzle 16 for corotation therewith, relative to the structure upstream of the scarfe plane 34. In practice, the scarfe plane 34 would be bridged by a thrust bearing structure (not shown), to ease the relative rotation.

On touch down of an associated aircraft (not shown), the doors 24 and 26 are opened to the positions shown in chain dotted lines, and then the structure 30a and 16 rotated through 1800, so as to cause the exhaust gases to exit the engine 12 in the direction indicated by the arrow 36. The gases are thus directed to the aperture 20, where the cascades 22 and the curved leading and trailing edges 38 and 40 of the aperture 20, deflect them in a direction which has a forward component. Reverse thrust is thus achieved.

It will be appreciated that on relative roation of the nozzle and cowl structure 16 and 30a, the exhaust gases will move off the centre line of the gas turbine engine 12 and an asymmetric thrust will occur. It follows an associated aircraft (not shown) must be provided with even numbers of gas turbine engines 12, spaced symmetrically about the aircraft longitudinal axis. Further, the rotatable nozzles of the engines on one side of the aircraft (not shown) must rotate in a direction opposite to that in which the nozzles on the other side thereof rotate.

Referring now to Figure 2, in which like parts have like numerals. In this embodiment of the present invention, the cowl 30 has no rotating portions. The jet pipe 32 however, terminates in a part spherical portion 32a over which a part spherical nozzle 16a fits insliding relationship. A gap 40 therebetween, is sealed by a piston ring seal 42.

In operation, the nozzle 16a is caused to rotate about an axis 44, until its exhaust gases are directed at the aperture 20 and its cascades 22. The rotation of the nozzle 16a occurs in a vertical plane containing the longitudinal axis of the jet pipe 32 and consequently, no asymmetric thrust is generated.

1. In combination, a gas turbine engine, an aircraft wing, a pylon projecting forwardly from said wing and having a free end from which said gas turbine engine is suspended such that its nozzle lies just rearward of the wing leading edge, wherein said nozzle is joined to the gas turbine engine for movement relative thereto in a manner which enables efflux to be ejected in an upwardly direction and said wing includes an exposable aperture through which said upwardly directed efflux may pass.

2. The combination of claim 1 wherein said nozzle is joined to the gas turbine engine via a thrust bearing which lies in a plane which is normal to the desired upwardly directed thrust line and the relative movement is rotary.

3. The combination of claim 1 wherein said nozzle is joined to the gas turbine engine via a spherical joint and the relative movement is rotary and occurs about the centre of the sphere.

4. The combination as claimed in any previous claim wherein the aperture in the wing includes cascade vanes positioned so as to receive said efflux and guide it forwardly over the wing and flaps are provided in the upper and lower surfaces of the wing for the purpose of closing the aperture when it is not in use.

5. The combination of a gas turbine engine, a wing and a pylon substantially as described in this specification and with reference to Figure 1 of the drawings.

6. The combination of a gas turbine engine, a wing and a pylon substantially as described in this specification and with reference to Figure 2 of the drawings.

Amendments to the claims have been filed, and have the following effect: (b) New or textually amended claims have been filed as follows:

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Aircraft structure with gas turbine engine and thrust reverser The present invention discloses, in combination, an aircraft structure having exhaust flow directing means, a gas turbine engine supported by the wing and including a thrust directing nozzle. The invention will now be described, by way of example and with reference to the accompanying drawings in which: Figure 1 depicts one embodiment of the inventive combination and Figure 2 depicts a further embodiment of the inventive combination. In Figure 1, an aircraft wing 10 supports a gas turbine engine 12 via a pylon 14. The pylon 14 extends forwardly of the wing 10 so that the exhaust nozzle 16 of the gas turbine 12 is positioned in the vicinity of the leading edge 18 of the wing 10. An aperture 20 is provided in the casing 10 and is positioned in line with the gas turbine engine 12, and downstream thereof. A member of elongate, aerofoil section cascades 22 are fixed in the aperture 20 and extend spanwise of the wing 10. Only two such cascades are shown in Figure 1, but any suitable number could be utilised. When an associated aircraft (not shown) takes off, cruises and descends, the aperture is closed by doors 24 and 26, so as to provide a smooth wing outer surface. The gas turbine engine 12 is enclosed in a streamlined cowl 30 and the downwstream end portion of both cowl 30 and the jet pipe 32 of the gas turbine engine 12 are scarfed in a common plane 34. The jet pipe 32 and the cowl 30 are bulged (not shown) in the area which includes the scarf, so as to enable them to be circular in the plane of the scarfe. The cowl portion 30a which is downstream of the scarfe plane 34 is fixed to the nozzle 16 for corotation therewith, relative to the structure upstream of the scarfe plane 34. In practice, the scarfe plane 34 would be bridged by a thrust bearing structure (not shown), to ease the relative rotation. On touch down of an associated aircraft (not shown), the doors 24 and 26 are opened to the positions shown in chain dotted lines, and then the structure 30a and 16 rotated through 1800, so as to cause the exhaust gases to exit the engine 12 in the direction indicated by the arrow 36. The gases are thus directed to the aperture 20, where the cascades 22 and the curved leading and trailing edges 38 and 40 of the aperture 20, deflect them in a direction which has a forward component. Reverse thrust is thus achieved. It will be appreciated that on relative roation of the nozzle and cowl structure 16 and 30a, the exhaust gases will move off the centre line of the gas turbine engine 12 and an asymmetric thrust will occur. It follows an associated aircraft (not shown) must be provided with even numbers of gas turbine engines 12, spaced symmetrically about the aircraft longitudinal axis. Further, the rotatable nozzles of the engines on one side of the aircraft (not shown) must rotate in a direction opposite to that in which the nozzles on the other side thereof rotate. Referring now to Figure 2, in which like parts have like numerals. In this embodiment of the present invention, the cowl 30 has no rotating portions. The jet pipe 32 however, terminates in a part spherical portion 32a over which a part spherical nozzle 16a fits insliding relationship. A gap 40 therebetween, is sealed by a piston ring seal 42. In operation, the nozzle 16a is caused to rotate about an axis 44, until its exhaust gases are directed at the aperture 20 and its cascades 22. The rotation of the nozzle 16a occurs in a vertical plane containing the longitudinal axis of the jet pipe 32 and consequently, no asymmetric thrust is generated. CLAIMS

4. The combination of a gas turbine engine, a wing and a plyon substantially as described in this specification and with reference to Figure 1 of the drawings.

1. In combination, a gas turbine engine, an aircraft wing, a pylon projecting forwardly from said wing and having a free end from which said gas turbine engine is suspended such that its nozzle lies just rearward of the wing leading edge, wherein said nozzle is joined to the gas turbine engine for rotary movement relative thereto in a manner which enables efflux to be ejected in an upwardly direction said join being in a plane which is normal to said upward direction and said wing includes an exposable aperture through which said upwardly directed efflux may pass.

2. The combination of claim 1 wherein said nozzle is joined to the gas turbine engine via a thrust bearing which lies in said plane which is normal to the desired upwardly directed thrust line.

3. The combination as claimed in any previous claim wherein the aperture in the wing includes cascade vanes positioned so as to receive said efflux and guide it forwardly over the wing and flaps are provided in the upper and lower surfaces the wing for the purpose of closing the aperture when it is not in use.