Aircraft wing with wing tip seal panel assembly

An aircraft wing including: a main wing portion with a tip end, and a wing tip device rotatably coupled to the tip end of the main wing portion at a joint, the wing tip device rotatable at the joint about a first axis between a flight configuration and a ground configuration; and a seal panel assembly including: a seal panel extending across the joint; a first connecting element having a first end non-rotatably coupled to the seal panel and a second end rotatably coupled to the main wing portion such that the seal panel is rotatable about a second axis; and a second connecting element having a first end rotatably coupled to the seal panel and a second end rotatably coupled to the wing tip device, such that rotation of the wing tip device about the first axis causes the seal panel to rotate about the second axis.

RELATED APPLICATION

This application incorporates by reference and claims priority to United Kingdom patent application GB 2201786.7, filed Feb. 11, 2022.

TECHNICAL FIELD

The present invention relates to an aircraft wing comprising a seal panel assembly, and an aircraft comprising the aircraft wing.

BACKGROUND

There is an increasing trend to increase the wing span of aircraft, however there are many limiting factors such as meeting restrictions related to the size of taxiways, runways and terminal gates. One way of tackling these restrictions is to provide folding wing tips, where a wing tip device is moveable between a flight configuration for use during flight and a ground configuration for use during ground manoeuvres.

It is desirable to effectively cover the joint between the main wing portion and wing tip device, however existing solution are often complex to avoid clashing of the relevant structures whilst providing an aerodynamic profile in the flight configuration. Consequently, there is a need to cover the folding wing tip mechanism simply and effectively.

SUMMARY

A first aspect of the invention provides an aircraft wing comprising: a main wing portion with a tip end, and a wing tip device rotatably coupled to the tip end of the main wing portion at a joint, the wing tip device rotatable at the joint about a first axis between a flight configuration and a ground configuration; and a seal panel assembly, comprising: a seal panel extending across the joint; a first connecting element having a first end non-rotatably coupled to the seal panel and a second end rotatably coupled to the main wing portion such that the seal panel is rotatable about a second axis; and a second connecting element having a first end rotatably coupled to the seal panel and a second end rotatably coupled to the wing tip device, such that rotation of the wing tip device about the first axis causes the seal panel to rotate about the second axis.

With this arrangement, a simple mechanism for moving a seal panel is provided. The seal panel assembly is passively driven, and the seal panel rotates about a single axis. The seal panel is well placed during all stages of deployment (flight configuration, intermediate configuration and ground configuration) to cover the joint, or parts of the joint, beneath the seal panel. A single panel is about to cover the joint at all stages of deployment.

The first axis and the second axis may be substantially parallel. The seal panel and wing tip device may be configured to rotate in the same direction.

The second end of the first connecting element may be inboard of the seal panel. This assist in avoiding clashing of the seal panel with main wing portion during extended rotational range of the wing tip device.

The first connecting element may comprise a first arm portion and a second arm portion that meet at an elbow. This assists in avoiding a clash of the first connecting element with parts of the existing aircraft wing structure, such as the leading and/or trailing edge panels that may extend over a portion of the seal panel assembly.

A central axis of the first arm portion may extend at an angle less than 135 degrees with respect to a central axis of the second arm portion. A central axis of the first arm portion may extend at an angle less than 100 degrees with respect to a central axis of the second arm portion.

The seal panel may comprise a side panel having a face portion substantially perpendicular to the first axis, the side panel configured to extend over at least a portion of the first and second connecting elements in the ground configuration. This arrangement may provide additional coverage and protection to the connecting elements, the joint, or to other parts extending through the joint such as electrical harnesses.

An inboard edge of the side panel may be arcuate. This may allow the inboard edge to substantially conform to the respective outboard edge of the main wing portion, such that the gap between the side panel and main wing portion is minimised.

The side panel may be a first side panel located towards a first end of the joint, and the seal panel may comprise a second side panel located towards a second end of the joint. This assists in protecting from the leading and trailing edge directions of the wing.

The first connecting element and second connecting element may be located between the first and second side panels. This arranged protects the first and second connecting elements.

The seal panel may have a perimeter edge, and substantially the entire perimeter edge may be adjacent one of an outer skin of the main wing portion and an outer skin of the wing tip device in the flight configuration. This ensures the aerodynamic profile of the wing.

The aircraft wing may further comprise a seal for sealing between the seal panel and the surrounding structure of the main wing portion and the wing tip device in the flight configuration, wherein the seal extends along substantially the entire perimeter of the seal panel.

The aircraft wing may further comprise a power system extending across the joint at a chordwise position, wherein the seal panel assembly is located at a chordwise position of the power system extending across the joint such that the seal panel is arranged to cover the power systems. With this arrangement, the seal panel may provide access to the power system.

The main wing portion may be rotatable coupled to the wing tip device by a plurality of lugs. The seal panel assembly may be located at a chordwise position of the lugs such that the seal panel is arranged to cover the plurality of lugs. With this arrangement, the seal panel may provide access to the lugs.

The seal panel assembly may be a first seal panel assembly arranged to cover a first portion of the joint, and the aircraft wing may comprise a second seal panel assembly arranged to cover a second portion of the joint.

The seal panel may extend across the joint on an upper surface of the aircraft wing.

A further aspect of the invention provides an aircraft comprising the aircraft wing of the first aspect.

Unless stated otherwise, the term ‘substantially’ is intended to refer to deviations due to manufacturing tolerances and the like.

DETAILED DESCRIPTION OF EMBODIMENT(S)

FIG.1illustrates a typical fixed wing aircraft1. The aircraft1may have a port wing2and a starboard wing3that extend from a fuselage4. Each wing2,3may carry wing mounted engines9. The fuselage4has a nose5and a tail6. The tail6may have horizontal and vertical stabiliser surfaces7,8. The aircraft1may be a typical jet passenger transport aircraft although the invention is applicable to a wide variety of fixed wing aircraft types, including commercial, military, passenger, cargo, jet, propeller, general aviation, etc. with any number of engines attached to the wings2,3or fuselage4.

Each wing2,3of the aircraft1may have a main wing portion10that is a cantilevered structure with a length extending in a span-wise direction from a wing root to a wing tip, the root being joined to the aircraft fuselage4. A wing tip device20may be provided on the tip end of each wing2,3. The wings2,3are similar in construction so only the port wing2will be described in detail with reference toFIG.2.

The wing2may have a plurality of flight control surfaces, including slats12, ailerons13, air brakes/spoilers14, and flaps15. Whilst the aircraft1is shown with a particular quantity and configuration of control surfaces, it will be understood that the wing2may comprise a different number and/or arrangement of control surfaces.

The wing tip device20is a folding wing tip device20configured to rotate relative to the wing2at a joint11about a first axis. The joint11may extend from a leading edge to a trailing edge of the wing2. The joint11may be considered to extend generally chordwise, where the chord of the wing2is a line extending between the leading edge and trailing edge of the wing2. The first axis may be substantially parallel to a longitudinal axis of the aircraft1extending from the nose5to the tail6. Alternatively, the first axis may be angled with respect to the longitudinal axis of the aircraft1, for example within 30 degrees of the longitudinal axis and preferably within 10 degrees of the longitudinal axis. The folding wing tip device20may be rotated relative to the wing2by an actuator (not shown).

In this way, the wing tip device20is rotatable about the first axis between: (i) a flight configuration for use during flight (See, e.g.,FIGS.3and4) and (ii) a ground configuration for use during ground-based operations such as airport taxiing (See, e.g.,FIGS.5and6).

In the flight configuration, the wing tip device20extends outwardly and typically extends so as to maximise the wing span of the aircraft1. As such, an upper surface of the main wing portion10may abut or be adjacent an upper surface of the wing tip device20. Similarly, a lower surface of the main wing portion10may abut or be adjacent a lower surface of the wing tip device20.

In the ground configuration, the wing tip device20may extend upwardly, away from the flight configuration, such that the span of the aircraft wing2is reduced, although in alternative examples the wing tip device20may extend downwardly.

As shown inFIGS.5and6, the wing tip device20typically extends upwardly at an angle of substantially 90 degrees in the ground configuration, although it will be appreciated that the wing tip device20may extend up to any suitable angle, e.g. any angle between 45 degrees and 135 degrees.

It should be noted thatFIGS.4and6show a view of part of the aircraft wing2in which the majority of the leading edge panels of the wing2are removed and only a single leading edge panel25of the main wing portion10is shown. The lower cover of the main wing portion10and wing tip device20are similarly removed.

A seal panel31extends across the joint11, as shown inFIG.4in the flight configuration and inFIG.6in the ground configuration. The seal panel31may be substantially rigid. The seal panel31may be formed of any suitable material, e.g. aluminium, glass fibre reinforced composite, or carbon fibre reinforced composite.

The seal panel31is arranged to cover the joint at all stages of deployment between the flight configuration and ground configuration, as will be described below, thereby protecting the joint11. The seal panel31has a perimeter edge, and as shown inFIG.4, substantially the entire perimeter edge may abut or be adjacent the upper cover18of the main wing portion10and an upper cover29of the wing tip device20. In this way, the seal panel31may fit flush with the surrounding upper cover18,29of the aircraft wing2when in the flight configuration. This allows a smooth aerodynamic profile to be formed. In some examples, there may be a seal51for sealing the seal panel31with the surrounding structure of the main wing portion10and the wing tip device20in the flight configuration. The seal51may extend along substantially the entire perimeter of the seal panel31.

The lower and upper covers18,29may form part of the outer skin of the aircraft1.

FIG.7shows an example of the joint11between the main wing portion10and the wing tip device20. The joint11includes a first axis16about which the wing tip device20is configured to rotate relative to the wing2.

The joint11includes a series of interleaving lugs17(only one of which is shown inFIG.7). The lugs17each include a first pin hole18through which a pin (not shown) extends, and which defines the first axis16about which the wing tip device20rotates. The lugs17may also include a second pin hole for receiving a locking pin (not shown) for fixing the wing tip device20in the flight configuration.

The seal panel31extends across the joint11and is passively moved between a flight configuration and a ground configuration as the wing tip device20moves between the flight configuration and the ground configuration.

The seal panel31is part of a seal panel assembly30. The seal panel assembly30comprises a first connecting element32having a first end33anon-rotatably coupled to the seal panel31and a second end33brotatably coupled to the main wing portion10such that the seal panel31is rotatable about a second axis34(i.e. the second end33bis pivotally coupled to the main wing portion10). The second axis34may be substantially parallel to the first axis16, although offset from the first axis16. In this way, the seal panel31has a constant and pre-defined arc of travel about the second end33bof the first connecting element32. The seal panel31has a single axis of rotation.

The seal panel assembly30includes a second connecting element36having a first end37arotatably coupled to the seal panel31and a second end37brotatably coupled to the wing tip device20. It will be appreciated that the second connecting element36may be directly or indirectly coupled to the seal panel31, i.e. due to the first end33aof the first connecting element32being non-rotatably coupled to the seal panel31, the first end37aof the second connecting element36may be rotatably coupled to the first connecting element32such that the first end37aof the second connecting element36is indirectly coupled to the seal panel31via the first connecting element32.

The seal panel assembly30is such that rotation of the wing tip device20about the first axis16causes the seal panel31to rotate about the second axis34. In this way, the seal panel assembly30may be considered a slave mechanism passively driven by the actuator that folds the wing2.

The seal panel assembly30may comprise multiple first and second connecting elements32,36, such as two, three or more. This may assist in supporting the seal panel31.

The actuation of the seal panel assembly30will now be described with reference toFIGS.7to12.

FIGS.7and8show an example of the aircraft wing2in a flight configuration. In the flight configuration, as shown inFIG.8, the seal panel31may lie flush with the outer aerodynamic surface of the main wing portion10and the wing tip device20. The seal panel31may be substantially parallel to the outer aerodynamic surface of the main wing portion10and the outer aerodynamic surface of the wing tip device20.

The second end33bof the first connecting element32may be inboard of the seal panel31, wherein inboard refers to a spanwise position closer to the longitudinal axis of the aircraft1. This defines the centre of rotation of the seal panel31, and thereby helps to avoid clashing of the seal panel31with the main wing portion10.

The main wing portion10may include a leading edge panel25, as shown inFIG.8. The leading edge panel25may extend across at least a portion of the spanwise extent of the seal panel31. The leading edge panel25may extend over the rotatable coupling of the second end33bof the first connecting element32.

The first connecting element32may be elbow shaped, such that a first arm portion42aand a second arm portion42bmeet at an elbow43, so as to avoid clashing of the first connecting element32with the leading edge panel25when the seal panel assembly30is moved between the flight configuration and the ground configuration. The first arm portion42aand the second arm portion42bmay be fixedly connected, such that there is no relative rotation between the first and second arm portions42a,42b. The first arm portion42amay have a central axis angled with respect to a central axis of the second arm portion42b. The angle shown in the example ofFIGS.7and8is substantially 70 degrees, although the angle may be any suitable value. For example, the angle may be between 30 degrees and 150 degrees, and is preferably more than 100 degrees and less than 135 degrees. It will be appreciated that the most suitable angle for the elbow43will depend, at least partly, on the arrangement of the seal panel assembly30.

FIGS.9and10show an example of the aircraft wing2in an intermediate configuration between the flight configuration and the ground configuration. Specifically,FIGS.9and10show the wing tip device20rotated by approximately 45 degrees about the first axis16with respect to the position of the wing tip device20in the flight configuration.

It will be appreciated that the seal panel assembly30may comprise multiple first and second connecting elements32,36. The seal panel assembly30may include a different number of first connecting elements32to second connecting elements36. The example shown inFIG.9includes two first connecting elements32and four second connecting elements36. For the purposes of clarity, only one of the first connecting elements32and second connecting elements36is labelled inFIG.9.

Due to the particular kinematics of the seal panel assembly30, the seal panel31correspondingly rotates about the second axis34. The seal panel31is rotatable in the same direction as the wing tip device20, such that rotation of the wing tip device20in an anti-clockwise direction about the first axis16(when viewed from the front of the aircraft1or aircraft wing2) is accompanied by a corresponding anti-clockwise rotation of the seal panel31about the second axis34, and vice-versa. The seal panel31only rotates with the wing tip device20, and in the same constant angular direction, such that the seal panel31rotates in a constant arc about the second axis34.

However, it will be appreciated that the rotation speeds of the wing tip device20about the first axis16and the seal panel31about the second axis34may differ, such that the rotation of the wing tip device20by a first angle may be accompanied by rotation of the seal panel31by a second angle different to the second angle. In the example shown inFIGS.9&10, the seal panel31has rotated less than the wing tip device20. Specifically, the seal panel31is shown to have rotated approximately 35 degrees in the intermediate configuration although it will be appreciated that the term ‘intermediate configuration’ may refer to any position in between the flight and ground configurations.

It will be appreciated that the exact rotation of seal panel31depends on the length of the second connecting element36, as well as the position of its two ends37a,37b. However, it has been realised that particular advantages are provided when the kinematics of the seal panel assembly30are such that the distance between the seal panel31and the outer surface of the wing tip device20are minimised during rotation between the flight configuration and the ground configuration. For examples, this may ensure that the seal panel31covers the first and second connecting elements32,36during all rotation between the flight configuration and ground configuration. This arrangement may similarly protect other components within the joint11, such as actuators or electrics.

The seal panel31is non-rotatably coupled to the first connecting element32, with the first connecting element32rotatably coupled at its other end, i.e. the second end33b. This arrangement simplifies the movement of the seal panel31, such that it rotates about a single axis, i.e. the second axis34. In particular, this may ensure that once the seal panel assembly30is moved from the flight configuration, the seal panel31is angled downwardly towards the main wing portion10at all positions between the flight configuration and the ground configuration. This may allow any runoff from the seal panel31(e.g. residue/contaminants/de-icer on the seal panel31) to fall towards the main wing portion10, away from any components under the seal panel31such as actuators, or the remainder of the seal panel assembly30. This can be particularly beneficial when the wing2has dihedral, as is the case in the present example.

It will be appreciated fromFIGS.9and10that the elbow43in the first connecting element32assists in avoiding clashing of the first connecting element32with the leading edge panel25. In particular, it will be appreciated fromFIGS.9and10that the leading edge panel25may be located between the first end33aof the first connecting element32and the second end33bof the first connecting element32, such that the elbow43assists in avoiding the first connecting element32clashing with the leading edge panel25.

Further rotation of the wing tip device20about the first axis16results in the seal panel31correspondingly rotating about the second axis34towards a ground configuration, such as shown inFIGS.11and12.

FIGS.11and12show the wing tip device20rotated by approximately 90 degrees with respect to the flight configuration, however it will be appreciated that the ground configuration may be any suitable angle with respect to the flight configuration, particularly in which the wing span of the aircraft1is reduced with respect to the flight configuration.

In the ground configuration, the seal panel31may be angled with respect to the surface of the main wing portion10and the surface of the wing tip device20. In the example shown inFIGS.7to12, the seal panel assembly30is configured to maintain the seal panel31at an angle to the surface of the main wing portion10that is less than the angle between the surface of the wing tip device20and the surface of the main wing portion10.

The angle between the seal panel31and the surface of the main wing portion10shown inFIG.12is approximately 65 degrees, whilst the surface of the wing tip device20is angled with respect to the surface of the main wing portion10by approximately 90 degrees, such that the angle between the surface of the wing tip device20and the seal panel31is approximately 25 degrees, although it will be appreciated that the respective angles may be any suitable values.

In some examples, the angle between the surface of the wing tip device20and the seal panel31may be anything between 5 degrees and 85 degrees. The angle between the surface of the wing tip device20and the seal panel31is preferably between 20 degrees and 45 degrees.

The seal panel assembly30avoids the need for a more complicated arrangement for passively (or actively) moving the seal panel31between the flight and ground configurations. There is no need for a complicated linkage arrangement, and instead the seal panel assembly30may be connected to the main wing portion10at only a single point (i.e. the second end33bof the first connecting element32) and connected to the wing tip portion20at only a single point (i.e. the second end37bof the second connecting element36).

Passive actuation of the seal panel assembly30, using the existing movement of the wing tip device20, allows the use of more complicated mechanisms and additional actuators to be avoided. As a result, a simplified and more reliable way of moving the seal panel31may be provided.

FIGS.13to16show an example substantially similar to the example shown in relation toFIGS.7to12, with the addition of a side panel46.

The side panel46may be coupled to the seal panel31and/or may be coupled to the first connecting element32. The side panel46may include a face portion47substantially perpendicular to the second axis34.

The side panel46may be configured to extend over at least a portion of the first and second connecting elements32,36in both the flight configuration and the ground configuration. In this way, the side panel46may protect the first and second connecting elements32,36. This may be particularly advantageous in the ground configuration, where the first and second connecting elements32,36would otherwise be exposed to the external environment when viewed fore or aft of the seal panel assembly30, i.e. when viewed in a direction substantially parallel to the longitudinal axis of the aircraft1. In the flight configuration, the side panel46extends into the existing wing structure and is hidden from view on the external surface on the wing1.

The side panel46may be shaped so as to maximise the coverage and protection that the side panel46may provide to the seal panel assembly30, whilst avoiding clashing of the side panel46with the main wing portion10and wing tip device20.

The side panel46may have a first edge48a. The first edge48amay be arcuate. The first edge48ais an edge adjacent the main wing portion10, i.e., an inboard edge. The side panel46may include a second edge48badjacent the wing tip device20, i.e. an outboard edge.

The first edge48amay be a circular arc. The radius of the circular arc may be substantially the same as the length of the first arm portion43a, i.e. within 5-10% of the length of the first arm portion43a, so as to minimise the clearance between the first edge48aand the surface of the main wing portion10whilst avoiding undesirable contact with the main wing portion10during movement from the flight configuration (FIG.13), to the intermediate configuration (FIG.14), to the ground configuration (FIG.15).

The second edge48bmay be similarly shaped to minimise the clearance between the second edge48band the surface of the wing tip device20, whilst avoiding contact with the wing tip device20.

In some examples, the seal panel assembly30may comprise first and second side panels46a,46b.FIG.16shows an example in which a first side panel46ais located towards a first end of the joint11(e.g. towards a leading edge of the wing2) and a second side panel46bis located towards a second end of the joint11(e.g. towards a trailing edge of the wing2). In this way, the joint11and any other components (such as actuators and the like) may be protected by the side panels46a,46b.

In some examples, the first connecting element32and second connecting element36may be located between the first and second side panels46a,46b.FIG.16shows such an example. By locating the first connecting element32and second connecting element36between the first and second side panels46a,46b, the connecting elements32,36may be protected by the side panels46a,46b.

It will be clear to the skilled person that the examples described above may be adjusted in various ways.

In above-described examples, the aircraft wing2has a leading edge and a trailing edge, and the seal panel31extends the majority of the distance between the leading and trailing edges (e.g. 60-70%). This allows the seal panel31to extend over the entire joint11between the main wing portion10and the wing tip device20.

In alternative examples, the seal panel31may extend over less of the distance between the leading and trailing edges.

In some examples, there may be a plurality of seal panel assemblies30a,30bthat each extend over a different portion of the joint11.FIGS.17and18show an example in which a first seal panel31aof a first seal panel assembly30aextends over a first portion of the joint11and a second seal panel31bof a second seal panel assembly30bextends over a second portion of the joint11.

In some examples, the seal panels31,31a,31bdo not extend across the lugs17or at least only extend over a portion of the lugs17. In such examples, the seal panels31a,31bmay be utilised to protect other systems of the wing2and/or to provide access to such systems.

In the example shown inFIGS.17and18, the first seal panel31aextends across a portion of the leading edge panel25of the main wing portion10and a leading edge panel of the wing tip device26. Similarly, the second seal panel31bextends across a portion of the trailing edge panel27of the main wing portion10and a trailing edge panel28of the wing tip device20.

A power system50(e.g. an electrical harness) is shown to extend adjacent the leading edge of the wing2and within the space between the leading edge panels25,26and the wing box of the wing2. A similar power system50may be located adjacent the trailing edge within a space between the trailing edge panels27,28and the wing box of the wing2.

By providing a seal panel assembly30,30a,30bacross the joint11adjacent to the power systems50(such that the power systems50are at approximately the same chordwise and spanwise positions on the wing2), the seal panel(s)31,31a,31bmay be removed to provide access to the power systems50. This can assist in the installation, inspection and repair of the power systems50.

It will be appreciated that the seal panel assembly30,30a,30band associated seal panel31,31a,31bmay extend across the lugs17and/or power systems50(such that the lugs17and/or power systems50are at approximately the same chordwise and spanwise positions on the wing2), or any other part of the joint11. This may include a single seal panel31, such as described in the examples relating toFIGS.7to16, or may include two or more seal panels31a31bthat each extend across respective portions of the joint11. It will be appreciated that there may be any arrangement and any number of the seal panel assemblies30,30a30band associated seal panels31,31a,31b.

In some examples, the seal panel assembly30,30a,30bmay comprise multiple first and second connecting elements32,36, such as two, three or more. This may assist in supporting the seal panel31,31a,31b.

It will be appreciated that, whilst the examples describe joint11arranged such that the wing tip device10is rotated upwardly when moved to the ground configuration, the joint11may be such that the wing tip device is rotated downwardly when moved to the ground configuration. In such examples, the seal panel31,31a,31bmay alternatively cover a lower surface of the wing2.

Where the word ‘or’ appears this is to be construed to mean ‘and/or’ such that items referred to are not necessarily mutually exclusive and may be used in any appropriate combination.