GB2554882A

GB2554882A - An actuator mountable within an aircraft wing

Info

Publication number: GB2554882A
Application number: GB1617262.9A
Authority: GB
Inventors: Wright Philip
Original assignee: Airbus Operations Ltd
Current assignee: Airbus Operations Ltd
Priority date: 2016-10-11
Filing date: 2016-10-11
Publication date: 2018-04-18
Also published as: GB201617262D0

Abstract

An actuator 51 mountable within an aircraft wing comprises an actuating member 52 to deploy a slat 31 from the wing when the actuating member is moved in a first direction, and to deploy a spoiler 41 from the wing when said actuating member is moved in a second direction. The actuator may comprise an arm which rotates in both the first and second directions. The slat and spoiler may be biased by springs 39, 49. The actuator may form part of a wing assembly 21. The aircraft wing may comprise inboard and outboard portions (18, 17, figure 2) where the outboard portion can fold relative to the inboard portion, and where the wing assembly is found on either portion.

Description

(54) Title of the Invention: An actuator mountable within an aircraft wing Abstract Title: Actuator for aircraft wing slat and spoiler (57) An actuator 51 mountable within an aircraft wing comprises an actuating member 52 to deploy a slat 31 from the wing when the actuating member is moved in a first direction, and to deploy a spoiler 41 from the wing when said actuating member is moved in a second direction. The actuator may comprise an arm which rotates in both the first and second directions. The slat and spoiler may be biased by springs 39, 49. The actuator may form part of a wing assembly 21. The aircraft wing may comprise inboard and outboard portions (18, 17, figure 2) where the outboard portion can fold relative to the inboard portion, and where the wing assembly is found on either portion.

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AN ACTUATOR MOUNTABLE WITHIN AN AIRCRAFT WING

TECHNICAL FIELD [0001] The present invention relates to an actuator mountable within an aircraft wing. The present invention also relates to a wing assembly comprising the actuator, to a wing for an aircraft comprising the wing assembly and to an aircraft comprising the wing according to the invention.

BACKGROUND [0002] Aircraft must operate across a large flight envelope over which the wings need to create lift to keep the aircraft flying in a controlled manner at various airspeeds. Therefore, a wing having a single geometry is normally not sufficient for creating the required lift in, for example, landing and cruise without unacceptable disadvantages such as too much drag.

[0003] As a result, aircraft wings are designed with control surfaces, such as slats, flaps, and spoilers, which can be moved to alter the characteristics of the wings to alter their lift coefficient so that the required amount of lift is created for a given airspeed.

[0004] More than one type of control surface is often used and multiple units of the control surfaces can usually be found along the span of the leading edge of an aircraft wing. However, the systems for deploying such control surfaces are often complicated, heavy, and large resulting in a reduction in aircraft efficiency. Furthermore, in aircraft with wingtips that fold to make them compatible with airport gate width restrictions, it is difficult to provide multiple systems that extend across the fold.

SUMMARY [0005] According to the invention, there is provided an actuator mountable within an aircraft wing, the actuator comprising an actuating member to deploy a slat from said wing when said actuating member is moved in a first direction, and to deploy a spoiler from said wing when said actuating member is moved in a second direction.

- 1 [0006] Preferably, the actuating member is configured to contact and push a slat into a deployed position when the actuating member is moved in said first direction.

[0007] The actuating member may have a slat contacting surface to contact and push a slat when the actuating member is moved in said first direction.

[0008] In a preferred embodiment, the actuating member is configured to contact and push a spoiler into a deployed position when the actuating member is moved in said second direction.

[0009] The actuating member may have a spoiler contacting surface to contact and push a spoiler when the actuating member is moved in said second direction.

[0010] Preferably, the actuating member is rotatable in each of said first and second directions.

[0011] In some embodiments, the actuating member comprises an arm configured to be mountable within an aircraft wing for rotation about an axis extending through an end of the arm.

[0012] According to another aspect of the invention, there is provided a wing assembly for an aircraft comprising a slat and a spoiler each being mountable to an aircraft wing and an actuator according to the invention mountable within the wing for deploying the slat and the spoiler.

[0013] Preferably, the slat has a face configured so that the actuating member contacts said face to push the slat into its deployed position when the actuating member is moved in said first direction.

[0014] Preferably, the spoiler has a face configured so that the actuating member contacts said face to push the spoiler into its deployed position when the actuating member is moved in said second direction.

[0015] The slat and the spoiler are preferably rotatably mountable to an aircraft wing.

[0016] In a preferred embodiment, the wing assembly comprises a slat biasing member for retaining the slat in a stowed position, the actuating member being configured to push the slat into its deployed position against a bias generated by

-2the slat biasing member when the actuating member is moved in said first direction.

[0017] Preferably, the slat biasing member is a spring.

[0018] In a preferred embodiment, the wing assembly comprises a spoiler biasing member for retaining the spoiler in a stowed position, the actuating member being configured to push the spoiler into its deployed position against a bias generated by the spoiler biasing member when the actuating member moves in said second direction.

[0019] Preferably, the spoiler biasing member is a spring.

[0020] In a preferred embodiment, the slat, spoiler, and the actuating member are mounted for rotation about a common axis.

[0021] According to another aspect of the invention, there is provided an aircraft wing comprising a wing assembly according to the invention.

[0022] The aircraft wing may comprise an inboard portion and an outboard portion, the outboard portion being foldable relative to the inboard portion, wherein the wing assembly is part of the outboard portion.

[0023] The aircraft wing may comprise an inboard portion and an outboard portion, the outboard portion being foldable relative to the inboard portion, wherein the wing assembly is part of the inboard portion.

[0024] According to another aspect of the invention, there is provided an aircraft comprising the aircraft wing according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS [0025] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0026] Fig. 1 shows a schematic perspective view of a known aircraft;

[0027] Fig. 2 shows a schematic front view of the aircraft shown in Fig. 1 with outboard portions of its main wings in a folded position;

[0028] Fig. 3 shows a schematic cross-sectional view of a wing assembly comprising an actuator for selectively deploying a slat and a spoiler, the actuator being shown in its neutral position;

-3[0029] Fig. 4 shows a schematic cross-sectional view of the wing assembly shown in Fig. 3 after the actuator has been rotated in a first direction to deploy the slat; and [0030] Fig. 5 shows a schematic cross-sectional view of the wing assembly shown in Fig. 3 when the actuator has been rotated in a second direction to deploy the spoiler.

DETAILED DESCRIPTION [0031] Referring to Figs. 1 and 2, a commercial aircraft 1 of known configuration is shown. The aircraft 1 comprises a fuselage 2, main wings 3, tail planes 4, and a vertical tail 5 which all extend from the fuselage 2.

It is known that one option for increasing the efficiency of the main wings 3 is to increase their aspect ratio. That is, the span of the main wings 3 may be increased in order to reduce drag while maintaining the lift characteristics of the main wing 3.

[0032] The main wings 3 comprises an aerofoil shaped cross-section which tapers towards a wing tip 6 at the extremities of the span. The aerofoil shaped main wings 3 comprise a leading edge 7 and a trailing edge 8 which are connected by an upper surface 9 and a lower surface (not shown). During flight airflow is first influenced by the leading edge 7. Therefore, the leading edge 7 is the most upstream point of the main wings 3 and the trailing edge 8 is the furthest downstream point.

[0033] The main wings 4 further comprise movable control surfaces which are configured to vary the amount of lift generated. Fift devices such as slats 12 are provided along the leading edge 7 of the main wings 3. The slats 12 are configured to increase the critical angle of attack, which is the angle at which airflow detaches from the upper surface 9 of the main wings 3 when the slats 12 are deployed. Therefore, the aircraft 1 is able to fly a higher angle of attack, than when the slats 12 are retracted, which allows a larger amount of lift to be generated. The slats 12 are deployed when the aircraft 1 is flying at low speed, for example, during landing.

-4[0034] Flaps 13 are located along the trailing edge 8 and are configured to increase the camber of the main wings 3 which increase the lift coefficient of the main wings 3 when they are deployed. Spoilers 14 are located in the upper surface 9 and are configured to decrease the lift generated by the main wings 3 when they are deployed. Spoilers 14 are deployed during cruise to offload excess lift caused by gusts or manoeuvres and can be deployed after landing to decrease lift and increase drag.

[0035] When deployed, a spoiler 14 extends at an angle to the profile of the main wings 3 into the airflow over the main wing 3. The extension of the spoiler 14 into the airflow causes the flow behind the spoiler 14 to separate from the upper surface 9 of the section of the main wing 3 in which the spoiler 14 has been deployed. This causes a controlled stall over the section of the main wing 3 downstream if the deployed spoiler 14 which greatly reduces, or ‘dumps’, the lift created by the section of the main wing 3 downstream of the spoiler 14.

[0036] The main wings 3 may further comprise a folding system 16, shown in Fig. 2, configured to fold an outboard portion 17 of the main wings 3 along a fold line (F) relative to an inboard portion 18 of the main wings 3. This allows the aircraft 1 with the enlarged wingspan to access existing terminal gates.

[0037] However, this may mean that there are a number of control surfaces which are located on the outboard portion 17 on one side of the fold line (F). This means that complex systems must be developed to connect the outboard control surfaces to the inboard controls to enable their deployment. Furthermore, the weight of the main wings 3 is increased due to the control systems in the outboard portions 17 and the presence of the folding system 16. An alternative is to have no control systems in the outboard portions 17 which can result in an amount of lift inconsistent with the section of the flight envelope in which the aircraft 1 is flying.

[0038] The present invention helps to overcome the above problems of complexity and increased weight of the main wings 3 by combining the functionality and reducing the complexity of the control systems and

-5 reducing the number of control systems on the main wing 3, which is particularly important in the foldable outboard portions 17 of the main wings 3. However, the present invention can also be employed in other portions of the main wings 3, or in wings 3 which do not have foldable outboard portions 17, with the aim of reducing weight.

[0039] Referring now to Fig. 3, a wing assembly 21 for a portion of an aircraft wing 3, shown in Fig. 1, is shown. The wing assembly 21 is shown in a neutral position in which all control surfaces are in their stowed positions in which they are retracted within a leading edge 26 of the wing

3. In its neutral position, the wing assembly 21 has an aerofoil shaped cross-section having a leading edge 22 and a trailing edge (not shown) which are connected by an upper surface 23 and a lower surface 24.

[0040] The wing assembly 21 comprises a leading edge portion 26 which extends in the spanwise direction. The leading edge portion 26 is the first part of the wing assembly 21 which airflow contacts during flight when the wing assembly 21 is in its neutral position. The leading edge portion 26 comprises an upper surface 27 and a lower surface 28 which meet at the leading edge 22 of the wing assembly 21.

[0041] The upper surface 27 of the leading edge portion 26 forms a part of the upper surface 23 of the wing assembly 21 and the lower surface 28 of the leading edge portion 26 forms a part of the lower surface 24 of the wing assembly 21.

[0042] The wing assembly 21 further comprises a wing structure 29 located rearward of the leading edge portion. The wing structure 29 comprises the load carrying wing structure which is not shown in detail. The load carrying wing structure may comprise spar and ribs in a conventional configuration.

[0043] The wing assembly 21 further comprises a slat 31 rotatably mounted to the leading edge portion 26. The slat 31 has an aerofoil shaped cross-section which extends in the spanwise direction. The slat 31 comprises a leading edge 32 and a trailing edge 33 which are connected by an upper surface 34 and a lower surface 35.

-6[0044] When in the stowed position, the slat 31 is mounted to the leading edge portion 26 such that it is proximate the lower surface 28 of the leading edge portion 26 of the wing assembly 21. In the present embodiment, the upper surface 34 of the slat 31 is flush with the lower surface 28 of the leading edge portion 26 when the slat 31 is in its stowed position.

[0045] Furthermore, the lower surface 35 of the slat 31 is located inside the profile of the wing assembly 21. Therefore, the trailing edge 33 of the slat 31 is proximate to the leading edge 22 of the wing assembly 21 and the leading edge 32 of the slat 31 is distal from the leading edge 22, or proximate to the wing structure 31, when the slat 31 is in the stowed position. That is, the leading edge 32 of the slat 31 is further from the leading edge 22 of the wing assembly 21 than the trailing edge 33 of the slat 31, when the slat 31 is in its the stowed position. Therefore, the slat 31 is effectively up-side down and facing downstream.

[0046] The slat 31 further comprises a connecting member 37, partially shown in dotted lines, which connects the aerofoil-shaped cross-section to the point about which the slat 31 is rotatably mounted to the leading edge portion 26, its centre of rotation.

[0047] The connecting member 37 is a local feature. That is, the connecting member 37 does not extend the width of the slat 31 in the spanwise direction. For example, the connecting member 37 may be located in the centre of the slat’s width or alternatively, connecting members 37 may be located at either spanwise end of the slat 31.

[0048] In the present embodiment, the connecting member 37 protrudes from the lower surface 35 of the slat 31 in a chordwise direction and extends to the point about which the slat 31 is rotatably mounted on the leading edge portion 26. The connecting member 37 comprises an engagement face 38 which is configured to face substantially in the upward direction towards the upper surface 23 of the wing assembly 21. The engagement face 38 is configured to be engaged so that the slat 31

-7can be rotated from its stowed position to its deployed position, as will be described hereinafter.

[0049] The wing assembly 21 further comprises a slat biasing member 39 which is configured to urge the slat 31 in its stowed position shown in Fig. 3, as will be described in more detail hereinafter. The slat biasing member 39 may be, for example, but not limited to, a spring element such as a torsion spring which acts about the centre of rotation of the slat 31, or a return spring.

[0050] The wing assembly 21 further comprises a spoiler 41 rotatably mounted to the leading edge portion 26. In the present embodiment, the spoiler 41 comprises an upper surface 42 and a lower surface 43 which meet upstream at a leading edge 44 of the spoiler 41 and are connected downstream by a rear surface 45. However, in an alternative embodiment, the upper and lower surfaces 42, 43 of the spoiler 41 may meet downstream at a trailing edge (not shown).

[0051] The spoiler 41 extends in a spanwise direction and is mounted to the leading edge portion 26 such that it is proximate the upper surface 27 of the leading edge portion 26. In the present embodiment, the upper surface 42 of the spoiler 41 is flush with the upper surface 27 of the leading edge portion 26, when the spoiler 41 is in its neutral, stowed position.

[0052] As shown in the embodiment illustrated in Fig. 3, the leading edge 44 of the spoiler 41 is located at or proximate to the leading edge 22 of the leading edge portion 26 of the wing assembly 21. Furthermore, in the present embodiment, the lower surface 43 of the spoiler 41 acts as an engagement face 47 and is configured to be engaged so that the spoiler 41 can be rotated from its stowed position to its deployed position, as will be described in more detail hereinafter.

[0053] The spoiler 41 may further comprise a connecting member (not shown) extending from the lower surface 43 of the spoiler 41 to the point about which the spoiler 41 is rotatably mounted to the leading edge portion 26, its centre of rotation. However, it will be understood that in an

-8alternative embodiment, the spoiler 41 may have a different crosssectional shape and may comprise a connecting member having an engagement face in a similar manner to the slat 31.

[0054] The wing assembly 21 further comprises a spoiler biasing member 49 which is configured to urge the spoiler 41 in its stowed position shown in Fig. 3, as will be described in more detail hereinafter. The spoiler biasing member 49 may be, for example, but not limited to, a spring element such as a torsion spring which acts about the centre of rotation of the spoiler 41 or a return spring.

[0055] The wing assembly 21 further comprises an actuator 51 for selectively deploying the slat 31 and the spoiler 41 which are rotatably mounted to the leading edge portion 26 of the wing assembly 21. The actuator 51 comprises an actuating member 52 which is rotatably mountable within the wing assembly 21. The actuating member 52 may assume a neutral position in which both the slat 31 and the spoiler 41 are located in their stowed positions, as previously described.

[0056] The actuating member 52 is a local feature, as described in reference to the connecting member 37 of the slat 31. That is, the actuating member 52 does not extend the width of the wing assembly 21 in the spanwise direction. The actuating member 52 has a similar width and is located in a similar position along the span of the wing assembly 21 to the connecting member 37. For example, the actuating member 52 may be located in the centre of the wing assembly’s span or alternatively, actuating members 52 may be located at either spanwise end of the wing assembly 21.

[0057] The actuating member 52 comprises a slat contacting surface 53 which is configured to cooperate with the slat 31 when the actuating member 52 is rotated from its neutral position in a first direction, to rotate the slat 31 into a deployed position from the leading edge portion 26 of the wing assembly 21. More, specifically, the slat contacting surface 53 is configured to cooperate with the engagement face 38 of the connecting member 37 of the slat 31.

-9[0058] When the actuating member 52 is in the neutral position, the slat contacting surface 53 is configured to face substantially downwards and in a direction towards the lower surface 28 of the leading edge portion 26. In the present embodiment, the slat contacting surface 53 of the actuating member 52 is configured to abut the engagement face 38 of the slat 31 when the actuating member 52 is in its neutral position. Therefore, any clockwise rotation of the actuating member 52, against the bias of the slat biasing member 39 retaining the slat 31 in its stowed position, will result in the instant initiation of deployment of the slat 31.

[0059] The actuating member 52 further comprises a spoiler contacting surface 54 which is configured to cooperate with the spoiler 41 when the actuating member 52 is rotated from its neutral position in a second direction, to rotate the spoiler 41 into a deployed position from the leading edge portion 26 of the wing assembly 21. More specifically, the spoiler contacting surface 54 is configured to cooperate with the lower surface 43 of the spoiler 41 in the present embodiment.

[0060] When the actuating member 52 is in the neutral position, the spoiler contacting surface 54 is configured to face substantially upwards and in a direction towards the upper surface 27 of the leading edge portion 26. In the present embodiment, the spoiler contacting surface 54 of the actuating member 52 is configured to abut the lower surface 43 of the spoiler 41 when the actuating member 52 is in its neutral position. Therefore, any anticlockwise rotation of the actuating member 52, against the bias of the spoiler biasing member 49 retaining the spoiler 41 in its stowed position, will result in the instant initiation of deployment of the spoiler 41.

[0061] The actuator 51 may further comprise or be connected to a power supply (not shown) which is configured to enable the actuator 51 to be operable to rotate the actuating member 52 in the first direction, clockwise, to urge the slat 31 from its stowed position to its deployed position, and in the second direction, anticlockwise, to urge the spoiler 41 from its stowed position to its deployed position.

-10[0062] The actuator 51 may comprise a torque supplying device for supplying torque to the actuating member 52 such as, for example, but not limited to a geared electric rotary actuator or a hydraulic motor.

[0063] In the present embodiment, the actuating member 52 is mounted to the leading edge portion 26 for rotation about its axis of rotation A. The axis of rotation of the actuating member 52 is at or proximate to its upstream end 56 when the actuating member 52 is in its neutral position. The actuating member 52 has a common axis with the axis of rotation of the slat 31. Furthermore, the spoiler 41 is also mounted to the leading edge portion 26 such that it rotates about the common axis of rotation of the actuating member 52 and slat 31. That is, the actuating member 52 is configured to be mounted for rotation about a common axis A with an axis of rotation of the slat 31 and the spoiler 41.

[0064] Therefore, the slat contacting and spoiler contacting surfaces 53, 54 of the actuating member 52 do not move laterally relative to the engagement faces 38, 47 of the slat 31 and spoiler 41 which reduces friction and wear of the components. However, in an alternative embodiment, the axis of rotation of the slat 31 and/or spoiler 41 may be different to the axis of rotation of the actuating member 52.

[0065] In the present embodiment, the axis of rotation of the slat 31 is proximate its trailing edge 33 whilst, the axis of rotation of the spoiler 41 is proximate its leading edge 44.

[0066] Referring now to Fig. 4, a schematic cross-sectional view of the wing assembly 21 is shown when the actuator 51 has been rotated in the first direction to urge the slat 31 into its deployed position.

[0067] The actuating member 52 is rotated in the clockwise direction so that the slat contacting surface 53 of the actuating member 52 applies pressure on the engagement face 38 of the slat 31. The actuating member 52 is then rotated against the bias of the slat biasing member 39 which is configured to retain the slat 31 in its stowed position when the actuating member 52 is not cooperating with the slat 31.

- 11 [0068] When the actuating member 52 is rotated in the first direction, the spoiler biasing element 49 retains the spoiler 41 in its stowed position. The rear surface 45 of the spoiler 41 may abut the leading edge portion 26 to prevent the spoiler 41 being rotated further in the first direction than its stowed position, shown in Fig. 3.

[0069] When in its deployed position, the slat 31 extends from the leading edge portion 26 is located upstream of the leading edge 22 of the leading edge portion 26. That is, the incoming airflow contacts, or is affected by, the slat 31 first during flight when the slat 31 is in its deployed position. When in its deployed position, the leading edge 32 of the slat 31 is upstream of its trailing edge 33 such that the slat 31 is orientated similarly to a conventionally deployed slat, as shown in Fig. 4.

[0070] When in its deployed position, the trailing edge 33 and lower surface 35 of the slat 31 are spaced from the leading edge portion 26 form an airflow slot 58. The size of the airflow slot 58 may be determined by the angle through which the slat 31 is rotated from its stowed position, the axis of rotation of the slat 31, and the geometry of the slat 31. The deployed position of the slat 31 is between 110-175 degrees in the clockwise direction relative to the stowed position. Preferably, the deployed position of the slat 31 is 120 degrees in the clockwise direction relative to the stowed position.

[0071] When the wing assembly 21 is in the configuration shown in Fig. 4, the slat 31 is deployed in front of the leading edge portion 26. The airflow slot 58 allows air to flow between the lower surface 35 of the slat 31 and the upper surface 27 of the leading edge portion 26 to help keep airflow over the upper surface 23 of the wing assembly 21 from separating and attached closer to the trailing edge (not shown) of the wing assembly 21. This allows the main wing 3, shown in Fig. 1, to operate at a higher angle of attack before stalling. Therefore, the aircraft 1, shown in Fig. 1, can generate a higher lift co-efficient and so can fly at lower speed such as during landing.

- 12[0072] The slat 31 is configured so that, when it is in its deployed position, the wing 3 can assume a higher angle of attack. As the lift coefficient of an aircraft 1 varies with angle of attack, a higher coefficient of lift is produced as a result of the higher angle of attack thereby enabling the aircraft to fly at lower speeds, or to enable it to take off and land in shorter distances. The function achieved by the movement of the slat 31 into its deployed position is similar to the function achieved by the deployment of a conventional leading edge slat from the leading edge 7 of an aircraft wing 3, as this also results in an airflow slot being created behind the slat for the purpose of increasing lift.

[0073] When the slat 31 is in its deployed position and the actuating member 52 is rotated in the second direction to return the actuating member 52 to its neutral position, during flight the airflow continues to act on the slat 31. As the slat 31 is no longer being urged or retained in its deployed position by the actuating member 52, the dynamic pressure of the airflow acts on its upper surface 33 to rotate the slat 31 in the second direction, anticlockwise, back toward its stowed position. Therefore, the engagement face 38 of the slat 31 is urged against the slat contacting surface 53 of the actuating member 52 by the airflow when the slat 31 is being moved into its stowed position. Furthermore, the slat biasing member 39 may urge the slat 31 back into its stowed position when the actuating member 52 is rotated in the second direction from the slat deployed position towards its neutral position.

[0074] Referring now to Fig. 5, a schematic cross-sectional view of the wing assembly 21 is shown when the actuator 51 has been rotated in the second direction to urge the spoiler 41 into its deployed position.

[0075] The actuating member 52 is rotated in the anticlockwise direction so that the spoiler contacting surface 54 of the actuating member 52 applies pressure on the engagement face 47 of the spoiler 41. The actuating member 52 is then rotated against the bias of the spoiler biasing member 49 which is configured to retain the spoiler 41 in it stowed

-13 position when the actuating member 52 is not cooperating with the spoiler 41.

[0076] When the actuating member 52 is rotated in the second direction, the slat biasing element 39 retains the slat 31 in its stowed position. A part of the lower surface 35 of the slat 31 may abut the leading edge portion 26 to prevent the slat 31 being rotated further in the second direction than its stowed position, shown in Fig. 3.

[0077] When in its deployed position, the upper surface 42 of the spoiler 41 extends from the upper surface 27 of the leading edge portion 26 to separate the flow from the upper surface 23 of the wing assembly 21 and reduce the lift generated. The deployed position of the spoiler 41 is between 20-60 degrees in the anticlockwise direction relative to the stowed position. Preferably, the deployed position of the spoiler 41 is 3040 degrees in the anticlockwise direction relative to the stowed position.

[0078] When the spoiler 41 is in its deployed position, the lift component created by the wing 3 is reduced by creating a controlled stall over a portion of the wing 3 behind the spoiler 41.

[0079] When the spoiler 41 is in its deployed position and the actuating member 52 is rotated in the first direction to return the actuating member 52 to its neutral position, during flight the airflow continues to act on the spoiler 41. As the spoiler 41 is no longer being urged or retained in its deployed position by the actuating member 52, the dynamic pressure of the airflow acts on its upper surface 42 to rotate the spoiler 41 in the first direction, clockwise, back toward its stowed position. Therefore, the engagement surface 47 of the spoiler 41 is urged against the spoiler contacting surface 54 of the actuating member 52 by the airflow when the spoiler 41 is being moved into its stowed position. Furthermore, the spoiler biasing member 49 may urge the spoiler 41 back into its stowed position when the actuating member 52 is rotated in the first direction from the slat deployed position towards its neutral position.

[0080] The spoiler 41 is located much further forward on the wing chord than conventional spoilers at or proximate to the leading edge 22 of the

- 14wing assembly 21. Therefore, the upper surface 42 of the spoiler 41 is closer to the region of the aerofoil that generates the majority of the lift. This means that when the spoiler 41 is deployed so that the upper surface 42 extends from the leading edge portion 26 of the wing assembly 21, it is more effective at decreasing lift and so only a small deployment is required. The small deployment can also be effected quickly, due to the contact between the lower surface 43 of the spoiler 41 and the spoiler contacting surface 54 of the actuating member 52, which is important for decreasing the load on the outboard portions 17 of the main wings 3, shown in Fig. 1, during cruise.

[0081] The present invention can be used on the inboard portions 18 of the main wing 3 but is particularly advantageous when the wing assembly 21 is positioned in the foldable outboard portions 17 of the main wings 3 if such foldable outboard portions 17 are present. By employing the wing assembly 21 in the outboard portions 17, the number of systems across the foldline (F) is reduced because the wing assembly 21 combines the slat 31 and spoiler 41 systems into one or reduces the complexity of the systems required to move the control surfaces.

[0082] Not only does the wing assembly 21 reduce the complexity of the connection between the main wing 3 and the foldable outboard portions 17 but the wing assembly 21 helps to reduce the weight of the main wings 3, irrespective of its position on the main wings 3, which in turn lowers fuel consumption. Therefore, aircraft 1 using the wing assembly 21 are more efficient.

[0083] It will be appreciated that the wing assembly 21 comprising the slat 31, spoiler 41, and actuator 51 of the present invention may be incorporated into the main wings 3 of an aircraft that does not comprise foldable outboard portions 17.

[0084] Furthermore, it will be appreciated that the wing assembly 21 comprising the slat 31, spoiler 41, and actuator 51 of the present invention may be incorporated into the main wing 3 of an aircraft 1 that comprises inboard portions 18 and outboard portions 17 that are foldable relative to

-15 the inboard portions 18. In such an aircraft 1, the wing assembly comprising the slat 31, spoiler 41, and actuator 51 may be incorporated into either the inboard portion or the outboard portion 17 of the main wings 3 or both.

[0085] In addition to the wing assembly 21 comprising the actuator 51, other parts of the wing 3 may also be provided with conventional leading edge slats and spoilers. For example, if the wing assembly 21 is incorporated into the foldable outboard portions 17, the inboard portion 18 may be provided with control devices of a conventional type.

Claims

1. An actuator (51) mountable within an aircraft wing (3), the actuator (51) comprising an actuating member (52) to deploy a slat (31) from said wing (3) when said actuating member (52) is moved in a first direction, and to deploy a spoiler (41) from said wing (3) when said actuating member (52) is moved in a second direction.

2. An actuator (51) according to claim 1, wherein the actuating member (52) is configured to contact and push a slat (31) into a deployed position when the actuating member (52) is moved in said first direction.

3. An actuator (51) according to claim 2, wherein the actuating member (52) has a slat contacting surface (53) to contact and push a slat (31) when the actuating member (52) is moved in said first direction.

4. An actuator (51) according to any of claims 1 to 3, wherein the actuating member (52) is configured to contact and push a spoiler (41) into a deployed position when the actuating member (52) is moved in said second direction.

5. An actuator (51) according to claim 4, wherein the actuating member (52) has a spoiler contacting surface (54) to contact and push a spoiler (41) when the actuating member (52) is moved in said second direction.

6. An actuator (51) according to any preceding claim, wherein the actuating member (52) is rotatable in each of said first and second directions.

7. An actuator (51) according to any preceding claim, wherein the actuating member (52) comprises an arm configured to be mountable within an aircraft wing (3) for rotation about an axis extending through an end of the arm.

- 17

8. A wing assembly (21) for an aircraft (1) comprising a slat (31) and a spoiler (41) each being mountable to an aircraft wing (3), and an actuator (51) according to any preceding claim mountable within the wing (3) for deploying said slat (31) and said spoiler (41).

9. A wing assembly (21) according to claim 8, wherein the slat (31) has a face (38) configured so that the actuating member (52) contacts said face (38) to push the slat into its deployed position when the actuating member (52) is moved in said first direction.

10. A wing assembly (21) according to claim 8 or 9, wherein the spoiler (41) has a face (47) configured so that the actuating member (52) contacts said face to push the spoiler into its deployed position when the actuating member (52) is moved in said second direction.

11. A wing assembly (21) according to any of claims 8 to 10, wherein the slat (31) and the spoiler (41) are rotatably mountable to an aircraft wing.

12. A wing assembly (21) according to any of claims 8 to 11, comprising a slat biasing member (39) for retaining the slat (31) in a stowed position, the actuating member (52) being configured to push the slat into its deployed position against a bias generated by the slat biasing member (39) when the actuating member (52) is moved in said first direction.

13. A wing assembly (21) according to claim 12, wherein the slat biasing member (39) comprises a spring.

14. A wing assembly (21) according to any of claims 8 to 13, comprising a spoiler biasing member (49) for retaining the spoiler (41) in a stowed position, the actuating member (52) being configured to push the spoiler (41) into its deployed position against a bias generated by the spoiler biasing member (49) when the actuating member (52) moves in said second direction.

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15. A wing assembly (21) according to claim 14, wherein the spoiler biasing member (49) comprises a spring.

16. A wing assembly (21) according to any of claims 8 to 15, wherein the slat (31), the spoiler (41), and the actuating member (52) are mounted for rotation about a common axis (A).

17. An aircraft wing (3) comprising a wing assembly (21) according to any one of claims 8 to 16.

18. The aircraft wing (3) according to claim 17, comprising an inboard portion (18) and an outboard portion (17), the outboard portion (17) being foldable relative to the inboard portion (18), wherein the wing assembly (21) is part of the foldable outboard portion (17).

19. The aircraft wing according to claim 17, comprising an inboard portion (18) and an outboard portion (17), the outboard portion (17) being foldable relative to the inboard portion (18), wherein the wing assembly (21) is part of the inboard portion (18).

20. An aircraft (1) comprising the wing (3) according to any of claims 17 to 19.

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Intellectual

Property

Office

Mr Michael Shaw

10 March 2017

GB1617262.9

1-20