GB2515044A

GB2515044A - Aircraft wing arrangement

Info

Publication number: GB2515044A
Application number: GB1310406.2A
Authority: GB
Inventors: Richard Haskins; John Alan Jones
Original assignee: Airbus Operations Ltd
Current assignee: Airbus Operations Ltd
Priority date: 2013-06-12
Filing date: 2013-06-12
Publication date: 2014-12-17
Also published as: GB201310406D0

Abstract

An aircraft wing 4 extends outwardly from a wing root to a wing tip and includes a front portion 25 and a rear portion forming control surfaces 26 and includes upper and lower skins 15,16. The wing includes a plurality of fuel tanks 11-14. Each of the plurality of fuel tanks extends from an inboard region of the wing towards the wing tip and they have anti-slosh baffles located within them. A method of making an aircraft wing comprises the steps of providing a plurality of composite vessels (11-14, fig 4A) for the formation of fuel tanks; providing the vessels with upper and lower wing skin precursors (15P, 16P, fig 4B) and forming a cured primary structure (fig 4C) from the vessels and wing skin precursors.

Description

AIRCRAFT WING ARRANGEMENT

Background of the Invention

The present invention relates to an aircraft wing arrangement (such as a main wing or a tail structure, such as a vertical stabiliser or fin, or a horizontal stabiliser) and a method of making an aircraft wing arrangement.

Typical aircraft wing arrangements comprise several fuel tanks spaced along the length of the wing.

The object of the present invention is to provide an alternative aircraft wing arrangement and an alternative method of making an aircraft wing arrangement.

Summary of the Invention

In accordance with a first aspect of the present invention, there is provided an aircraft wing arrangement comprising an aircraft wing extending outwardly from a wing root to a wing tip and a plurality of fuel tanks, each of the plurality of fuel tanks extending from an inboard region of the wing towards the wing tip.

Those skilled in the art will recognise that the wing arrangement may comprise other fuel tanks in addition to said plurality of fuel tanks. For example, the wing arrangement may comprise a central fuel tank and/or a surge or vent tank located in the region of the wing tip.

The aircraft wing arrangement may comprise one of a left or a right wing of a fixed wing aircraft, or may comprise both the left and right wing of a fixed-wing aircraft, optionally with a centre wing-box therebetween.

The plurality of fuel tanks may optionally comprise two, three, four or five fuel tanks.

Each of the plurality of fuel tanks may extend side by side to one another. One or more, optionally more than one and optionally each, of the plurality of fuel tanks is optionally elongate.

Each of the plurality of fuel tanks may have a first end associated with (and preferably proximate to, or at) the wing root and a second end associated with (and preferably proximate to, or at) a wing tip. If the wing arrangement comprises a surge or vent tank located in the region of the wing tip, the second end of each of the plurality of fuel tanks may be proximate to the surge tank. One or more of the plurality of fuel tanks may be in fluid communication with the surge or vent tank, typically via a conduit.

It is preferred that one or more, optionally more than one and optionally each of the plurality of fuel tanks comprises composite material. One or more, optionally more than one and optionally each of the plurality of fuel tanks may comprise one or more walls which comprises composite material. A composite material typically comprises fibres (optionally in the form of a fabric) and a matrix, such as a resin. The fibre material may be a synthetic material (such as carbon fibre), as opposed to a natural material (such as wood) The size and position of the fuel tanks may be chosen to mitigate against the deleterious effects of uncontrolled engine rotor failure by mitigating against total fuel loss through any leak path that may be caused by debris.

The wing arrangement may optionally be a dihedral wing.

Alternatively, the wing arrangement may be an anhedral wing.

At least one, optionally more than one and optionally each, of the plurality of fuel tanks is provided with a fuel tank outlet. At least one fuel tank outlet may optionally he in fluid communication with another fuel tank (the fuel tank outlet allowing fuel to be supplied from one fuel tank to another) . At least one fuel tank outlet may be provided with a one-way valve operable to control egress of fuel from the fuel tank. At least one fuel tank outlet is in fluid communication with an aircraft engine fuel inlet conduit.

The location of a fuel tank outlet will depend, inter alia, on whether the wing is a dihedral or anhedral wing.

At least one, optionally more than one and optionally each of the plurality of fuel tanks is provided with at least one baffle arranged to inhibit movement of fuel in an inward and/cr outwards direction. At least one (optionally more than one and optionally each) baffle may comprise a plate provided with one or more apertures or recesses for allowing passage of fuel therethrough. Such baffles are often known as anti-slosh barriers or baffles; they typically inhibit movement of fuel along a fuel tank. Such movement of fuel may, in certain circumstances, have a destabilising effect on the aircraft and can, if not accounted for in design and construction, present a hazard to controlled flight. The baffles may typically be mutually spaced along the length of the fuel tank. At least one, optionally more than one and optionally each baffle may be provided with at least one one-way valve operable to permit fuel to move inwardly or outwardly. At least one of the baffles may optionally be provided with one or more vent spaces.

The wing arrangement may optionally be provided with at least one vent conduit. At least one of the plurality of fuel tanks may be provided with at least one vent conduit. Optionally, more than one of the plurality of fuel tanks may be provided with at least one vent conduit. Vent conduits may optionally form a fluid flow path from a fuel tank to a surge, or vent, tank, such a surge or vent tank optionally and typically being located in the wing tip portion of a wing.

The inboard part of the wing or of at least one fuel tank may be provided with a vent which may typically be located in an upper part of fuel tank.

The wing arrangement may be provided with one or more aircraft control structures, such as wing flap, aileron or rudder. The one or more aircraft control structures may be replaceable and/or interchangeable with alternative aircraft control structures having different characteristics. For example, the aileron may be interchangeable with a second aileron, for example, a longer aileron capable of producing increased roll.

A wing flap may be interchangeable with a second wing flap, for example, capable of producing more lift and more drag.

The wing arrangement may be provided with one or more wing arrangement leading edge components. The one or more leading edge components may be replaceable and/or interchangeable with alternative leading edge components having different characteristics.

The wing arrangement may comprise one or more engines, each engine receiving fuel from a respective fuel tank. Optionally, one fuel tank may provide fuel to only one engine.

In accordance with a second aspect of the present invention, there is provided a method of producing an aircraft wing arrangement, the method comprising: (i) Providing a plurality of composite vessels for the formation of fuel tanks therefrom; (ii) Providing the vessels with upper and lower wing skin precursors; and (iii) Forming a cured primary structure from the vessels and wing skin precursors.

The method of the second aspect of the present invention may be used to make the aircraft wing arrangement of the first aspect of the present invention.

Step (iii) optionally comprises subjecting the plurality of vessels and wing skin precursors to an elevated temperature to form the cured primary structure. This is typically known as heat or thermal curing. Alternatively or additionally, step (iii) may comprise irradiating the plurality of vessels and wing skin precursors to form the cured primary structure.

Irradiating may comprise irradiating with electromagnetic radiation (such as ultra violet, infra red or visible radiation) or with an electron beam, for example.

Alternatively or additionally, one or more of the vessels and upper and lower wing skin precursors may comprise two or more reactive components which react to form a matrix of a composite material. Typically, over time the two or more reactive components react to form a matrix.

At least one, more than one and optionally each of the plurality of vessels provided in step (i) may optionally be at least partially cured and optionally substantially fully cured. The vessels may be partially cured, sufficiently cured to enable handling of the vessels in the absence of any supporting structure (such as a former) At least one, more than one and optionally each of the plurality of vessels provided in step (i) may comprise substantially uncured composite precursor material. Such substantially uncured composite precursor material is curable to form a cured composite material. Uncured vessels may optionally be supported, for example, by an airbag and/or a mandrel.

Step (iii) typically cures the vessels fully (if not fully cured when prcvided in step (i) ) and cures the wing skin precursors.

The vessels provided in step (U are preferably adjacent to one another. The vessels provided in step (i) are optionally provided in side-by-side arrangement, optionally extending outwardly from a wing inboard region. Alternatively or additionally, one or more of the vessels may be arranged inward or outward of another at least one of the vessels.

Step (ii) may be performed using an automated laying machine.

The upper and lower wing skins may be formed by providing upper and lower wing skin precursors, and curing the same to form upper and lower wing skins. The upper and lower wing skins may be provided at the same time. Alternatively, the lower wing skin and upper wing skin may be provided consecutively. The upper and lower wing skin precursors may be urged Into engagement with the vessels before and/or during a curing process.

The method may comprise providing at least one, optionally more than one and optionally each vessel with at least one baffle arranged to inhibit movement of fuel in an inward and/or outwards direction.

At least one, optionally more than one and optionally each of the vessels may be elongate.

The method may comprise providing control surfaces and attaching the control surfaces to the cured primary structure.

The method may comprise providing one or more fuel supply conduits for the supply of fuel from one or more fuel tanks.

The method may comprise providing one or more vent conduits for the venting of gas (such as air and/or fuel vapour) from, or to, one or more fuel tanks.

The aircraft wing arrangement produced by the method of the second aspect of the present invention may optionally comprise one of a left or right wing of a fixed-wing aircraft, or may comprise both the left and right wing of a fixed-wing aircraft, optionally with a centre wing box therebetween. The aircraft wing arrangement produced by the method of the second aspect of the present invention may optionally comprise one or a left or right tail wing horizontal stabiliser.

The method may comprise adding additional features to the primary structure. For example, the method may comprise attaching a surge tank to the primary structure.

The method of the second aspect of the present invention may be used to make the aircraft wing arrangement of the first aspect of the present invention. The method of the second aspect of the present invention may therefore comprise the features of the aircraft wing arrangement of the first aspect of the present invention. Likewise, the aircraft wing arrangement of the first aspect of the present invention may comprise the features disclosed in relation to the method of the second aspect of the present invention. If the vessels provided in step (i) are at least partly cured, then the method of the second aspect of the present invention may be adapted by providing cured wing skins in step (ii), instead of wing skin precursors.

In accordance with a third aspect of the present invention, there is provided an aircraft wing arrangement made in accordance with the method of the second aspect of the present invention.

In each of the aspects of the present invention above, the wing arrangement could be a main wing of an aircraft, a tail wing structure (such as the lift generating portion of a tailplane, sometimes referred to as a horizontal stabiliser) or a fin (sometimes referred to as a vertical stabiliser) or rudder structure of a tail.

The term "composite" refers to a composite material comprising a fibrous component and a matrix, and includes uncured materials (such as a precursor to a cured matrix, such precursors typically being in the form of viscous liquids) The composite material may optionally be a synthetic composite material In which one or both of the fibrous component and the matrix Is synthetic (as opposed to being natural) The fibrous component, for example, may be synthetic (e.g. carbon fibre) The fibrous component may, for example, comprise individual short fibres; these are typically dispersed within a matrix.

Alternatively or additionally, the fibrous component may comprise lengths of fibre and/or a sheet of material comprising fibres. The matrix may typically comprise a resin.

In the precursor state, the matrix typically comprises a viscous liquid precursor which, on curing, forms a solid.

The fibrous component may optionally comprise carbon fibre. In this case, the matrix may comprise an epoxy resin. Those skilled in the art will realise that many different composite materials may be used.

The matrix of the composite material may be curable at a low temperature (for example, 80_l0000) . Alternatively, the matrix may be curable at a higher temperature (for example, 150-200°C)

Description of the Drawings

The present invention will now he described by way of example only with reference to the following figures of which: Figure 1 is a schematic perspective view of an aircraft comprising an example of an aircraft wing arrangement in accordance with an aspect of the present invention; Figure 2 is a schematic end view of the aircraft wing arrangement shown in Fig. 1; Figure 3 is a schematic cross-sectional view of the wing arrangement of Figure 2 taken along line AA; and Figure 4 shows an example of a method in accordance with an aspect of the present invention.

Detailed Description

Figure 1 is a schematic perspective view of an aircraft comprising a wing arrangement in accordance with the first aspect of the present invention.

The aircraft is denoted generally by reference numeral 1, and comprises a fuselage 2, a left wing 4 and right wing 5, each attached to a centre box (not shown) and a tail 6 comprising left tail plane 7, right tail plane 8, stabilising fin 9 and rudder 10. The left wing 4, right wing 5, left tail plane 7 and right tail plane 8 are examples of wing structures in accordance with the present invention, and are described in more detail below.

Left wing 4 will now be described in more detail with reference to Fig. 2. Left wing 4 comprises four composite fuel tanks 11, 12, 13, 14 which extend along the length of the wing 4 from a wing root to a surge tank 30 (best seen in Fig. 3) The wing 4 comprises upper wing skin 15 and lower wing skin 16 which are formed from composite material. The wing 4 comprises wing front portion 25 and control surfaces 26 (typically in the form of an aileron and a wing flap) at the rear of wing 4.

The wing 4 comprises various venting conduit and fuel outlet conduits, some of which are now described. Venting conduits 17, 18 extend from respective fuel tanks outwardly to the surge tank 30. Fuel outlet conduit 19 extends inwardly from respective fuel tanks towards the fuselage. Fuel outlet conduit 20 extends outwardly to a position in the middle of the wing from which it descends from the fuel tank through an engine-supporting pylon (not shown) to a jet engine (not shown) . Conduits 17, 18, 19 and 20 are all defined by pipes.

Each of the fuel tanks 11, 12, 13, 14 is provided with several anti-slosh baffles 31, 41, 51, 32, 42, 52, 33, 43, 53, 34, 44, 54, as is best seen in Figure 3. The baffles have been omitted from Fig. 2 for clarity. The anti-slosh baffles inhibit motion of fuel along the length of the fuel tank in which they are deployed. Each baffle comprises a plate with one or more apertures or recesses for the passage of fuel therethrough.

The method of manufacture of the wing 4 will now be described with reference to Fig. 4. Fully cured composite fuel-tank forming vessels 11, 12, 13, 14 are placed in side-by-side arrangement as can be seen in Fig. 4A. The vessels are made by depositing composite precursor in the form of a resin and fibrous material around a mandrel and then curing the composite precursor at elevated temperature and pressure. For example, Lhe fibrous maLerial may be wound around a former.

Suitable materials which could be used to make the fuel-tank forming vessels are ACG/Umeco EF6809 (from Umeco) and Hexcel M21E, which may typically be cured at about 170°C at a pressure of about 7 bar.

Pipes 67, 68, 69, 70 are situated in positions in which the formation of conduits is desired. Wing skin precursors 15? and 16? are then formed onto the precursor wing structure as shown in Fig. 43. This is typically achieved using a laying-up apparatus. The wing skin precursors are typically formed from composite precursor material. A press 100 is then used to compress the precursor wing structure, which is cured at elevated temperature to form a sturdy, self-supporting wing arrangement. The surge tank may then be incorporated into the wing arrangement. The control surfaces 26 and front wing portion 25 may be added to the wing arrangement.

Those skilled in the art will realise that the aircraft need not be provided with a surge tank, or a pressure-relief valve.

Those skilled in the art will realise that the fuel tanks need not be fully cured before being assembled together with the wing skins. The fuel tanks may typically be sufficiently cured so that they can be handled without damaging the fuel tanks.

The wings of the present invention may be anhedral or dihedral.

Those skilled in the art will realise that not all of the wing structures of an aircraft need be made by the methods of the present invention. For example, only two of the wing arrangements (such as the main wings or the horizontal stabilising tail structures) may be made by a method of the present invention.

Those skilled in the art will realise that different venting and fuel supply arrangements are possible.

Those skilled in the art will realise that the fuel tanks used in the method of the present invention do not have to be formed by a winding process around a former.

Where, in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims.

Claims

Claims 1. A method of producing an airoraft wing arrangement, the method comprising: (i) Providing a plurality of oomposite vessels for the formation of fuel tanks therefrom; (ii) Providing the vessels with upper and lower wing skin preoursors; and (iii) Forming a cured primary structure from the vessels and wing skin preoursors.
2. A method according to olaim 1 wherein at least one of the plurality of vessels provided in step (i) is at least partially cured.
3. A method aocording to claim 2 wherein at least one of the plurality of vessels provided in step (i) is substantially fully cured.
4. A method according to any of claims 1 to 3 wherein at least one of the plurality of vessels provided in step (i) comprises substantially uncured composite precursor material.
5. A method according to any preceding claim wherein step (iii) oomprises subjecting the plurality of vessels and wing skin precursors to an elevated temperature to form the cured primary struoture.
6. A method according to any preceding claimwherein in step (1), the vessels are adjacent to one another.
7. A method according to preceding claim wherein the vessels provided in step (1) are provided in side-by-side arrangement.
8. A method according to claim 7 wherein the vessels extend outwardly from a wing inboard region.
9. A method according to preceding claim wherein one or more of the vessels are arranged inward or outward of another at least one of the vessels.
10. A method aocording to any preceding olaim wherein the upper and lower wing skins are formed by providing upper and lower wing skin precursors, and curing the same to form upper and lower wing skins.
11. A method according to claim 10 wherein the upper and lower wing skins are provided at the same time.
12. A method according to claim 10 wherein the lower wing skin and upper wing skin are provided consecutively.
13. A method according to any of claims 10 to 12 wherein the upper and lower wing skin precursors are urged into engagement with the vessels before and/or during a curing process.
14. A method according to any preceding claim comprising providing at least one of said vessels with at least one barrier arranged to inhibit movement of fuel in an inward and/or outwards direction.
15. A method according to any preceding claim comprising providing one or more fuel supply conduits for the supply of fuel from one of more fuel tanks.
16. A method according to any preceding claim comprising providing one or more venting conduits for the venting of gas from one or more fuel tanks.
17. A method according to any preceding claim comprising providing controi surfaces and attaching the control surfaces to the cured primary structure.
18. A method according to any preceding claim comprising providing a surge tank and attaching the surge tank to the cured primary structure.
19. An aircraft wing arrangement comprising an aircraft wing extending outwardly from a wing root to a wing tip and a plurality of fuel tanks, each of the plurality of fuel tanks extending from an inboard region of the wing towards the wing tip.
20. An aircraft wing arrangement according to claim 19 wherein each of the plurality of fuel tanks extends side by side to one another.
21. An aircraft wing arrangement according to claim 19 or claim 20 wherein one or more of the plurality of fuel tanks is elongate.
22. An aircraft wing arrangement according to any of claims 19 to 21, wherein each of the plurality of fuel tanks has a first end associated with (and proximate to, or at) the wing root and a second end associated with (and proximate to, or at) a wing tip.
23. An aircraft wing arrangement according to claim 22 comprising a surge tank located in the region of the wing tip, the second end of each of the plurality of fuel tanks being proximate to the surge tank.
24. An aircraft wing arrangement according to any of claims 19 to 23 wherein one or more of the plurality of fuel tanks is comprised of composite material.
25. An aircraft wing arrangement according to any of claims 19 to 24 wherein at least one ci the plurality ci fuel tanks is provided with at least one barrier arranged to inhibit movement of fuel in an inward and/or outwards direction.
26. An aircraft wing arrangement according to any of claims 19 to 25 comprising at least one vent conduit.
27. An aircraft wing arrangement according to any of claims 19 to 26 comprising at least one fuel outlet conduit.
28. An aircraft wing arrangement according to any of claims 19 to 27 comprising one or more aircraft control structures.
29. An aircraft wing arrangement according to claim 28 wherein the one or more aircraft control structures are replaceable and/or interchangeable with alternative aircraft control structures having different characteristics.
30. A method of making an aircraft wing arrangement according to any of claims 19 to 29 in accordance with the method of any of claims 1 to 18.
31. An aircraft wing arrangement made in accordance with the method of any of claims 1 to 18.
32. An aircraft comprising an aircraft wing arrangement in accordance with any of claims 19 to 29 and 31.