(19)
(11)EP 3 388 331 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
04.12.2019 Bulletin 2019/49

(21)Application number: 18175169.4

(22)Date of filing:  28.04.2015
(51)Int. Cl.: 
B64C 9/02  (2006.01)
B64C 9/16  (2006.01)

(54)

SLIDABLE DIVERGENT TRAILING EDGE DEVICE

VORRICHTUNG MIT VERSCHIEBBARER DIVERGIERENDER AUSTRITTSKANTE

DISPOSITIF DE BORD DE FUITE DIVERGENT COULISSANT


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 06.06.2014 US 201414298105

(43)Date of publication of application:
17.10.2018 Bulletin 2018/42

(62)Application number of the earlier application in accordance with Art. 76 EPC:
15165345.8 / 2952429

(73)Proprietor: The Boeing Company
Chicago, IL 60606-1596 (US)

(72)Inventors:
  • JAMISON, Flint M.
    Chicago, IL 60606-1596 (US)
  • AMOROSI, Stephen R.
    Chicago, IL 60606-1596 (US)
  • KLEIN, Michael K.
    Chicago, IL 60606-1596 (US)

(74)Representative: Boult Wade Tennant LLP 
Salisbury Square House 8 Salisbury Square
London EC4Y 8AP
London EC4Y 8AP (GB)


(56)References cited: : 
EP-A1- 1 488 998
US-A- 2 405 726
US-A- 3 076 623
US-B1- 6 565 045
US-A- 2 147 360
US-A- 2 791 385
US-A1- 2012 261 519
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND



    [0001] A Divergent Trailing Edge (DTE) device can increase lift over drag (L/D) of a wing. The DTE may be fixed to an aft lower surface of a wing. However, a fixed DTE creates a load distribution that can have a significant collateral impact of requiring a stronger, heavier wing.

    [0002] A DTE may instead be hinged to an aft lower surface of a wing. A hinged DTE may be retracted to a stowed position, and it may be scheduled to extend during the less heavily loaded phases of flight, thus minimizing the collateral structural weight.

    [0003] A hinged DTE may be extended and retracted by an actuator and drive linkage. The actuator and linkage carry air loads and, therefore, are sized accordingly. If the actuator fails during flight, free surface flutter of the hinged DTE can occur. If the actuator and linkage are too large to fit within the airfoil, they are covered by an external fairing, which adds complexity, weight, and drag.

    [0004] US 6565045 B1 discloses an aerodynamic surface, such as a wing, empennage, angle of drift, nacelle pylon and the like for an aircraft includes at least one lightening hole pertaining to the trailing edge of the underwing, at least one hinged baffle that can be mounted in the lightening hole of the underwing, whereby the chord thereof is equal to a several hundredths of the chord of the aerodynamic surfacer and an actuator for the moveable baffle so that it can rotate around the hinge line.

    [0005] US 2012/261519 A1 discloses a gurney flap assembly having an actuator, a flexible or hinged body, the body flexing from a retracted to a deployed position in reaction to motion of the actuator, and a first seal extending along a first edge of the flexible body that flexes from the stowed position. Linear motion of the actuator output is transposed to the gurney flap thereby moving it from a retracted position into the airstream. This trailing edge device will improve airfoil lift.

    SUMMARY



    [0006] According to an embodiment herein, a wing comprises a trailing edge, and a divergent trailing edge device slideable along an aft surface of the trailing edge between a stowed position and a fully deployed position. The trailing edge device is located entirely within the trailing edge when stowed, and it increases lift over drag of the wing when deployed. The wing also comprises a cover on a lower surface of the divergent trailing edge device, the cover providing a sliding surface for the divergent trailing edge device.

    [0007] According to another embodiment herein, an aircraft comprises a wing including a trailing edge having a moveable flight control surface and a fixed surface. The aircraft further comprises a plurality of divergent trailing edge devices integrated with the moveable flight control surface, and a plurality of actuators for independent control of the divergent trailing edge devices. Each divergent trailing edge device is slideable between a stowed position entirely within the moveable flight control surface and a deployed position at least partially under the moveable flight control surface.

    [0008] According to another embodiment herein, a method performed during flight of an aircraft comprises sliding a divergent trailing edge device along a trailing edge of each aircraft wing to reduce lift over drag (L/D) of the wing; and thereafter stowing the divergent trailing edge device entirely within the trailing edge.

    [0009] These features and functions may be achieved independently in various embodiments or may be combined in other embodiments. Further details of the embodiments can be seen with reference to the following description and drawings.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0010] 

    FIG. 1 is an illustration of an aircraft.

    FIG. 2 is an illustration of a wing.

    FIG. 3A is an illustration of a divergent trailing edge device in a fully deployed position.

    FIG. 3B is an illustration of a divergent trailing edge device in a stowed position.

    FIG. 3C is an illustration taken along sectional lines 3C-3C in FIG. 3B.

    FIG. 4 is an illustration of a wing and a divergent trailing edge device at a trailing edge of the wing.

    FIG. 5 is an illustration of a wing, a divergent trailing edge device, and a cover for a lower surface of the divergent trailing edge device.

    FIG. 6 is an illustration of a wing, a divergent trailing edge device, and a cover for an upper surface of the divergent trailing edge device.

    FIG. 7 is an illustration of a divergent trailing edge device including a substantially straight stiffened panel.

    FIGS. 8A and 8B are illustrations of a wing including a plurality of divergent trailing edge devices.

    FIG. 9 is an illustration of a method of enhancing performance of an aircraft.


    DETAILED DESCRIPTION



    [0011] Reference is made to FIG. 1, which illustrates an aircraft 110 including a fuselage 120, wings 130, and empennage 140. One or more propulsion units 150 are coupled to the fuselage 120, wings 130 or other portions of the aircraft 110.

    [0012] Reference is made to FIG. 2. Each wing 130 includes a leading edge and a trailing edge 210. The trailing edge 210 may include fixed surfaces 220 and moveable flight control surfaces 230. Examples of the moveable flight control surfaces 230 include, but are not limited to, ailerons, flaps, flaperons, and slats.

    [0013] The wing 130 further includes at least one divergent trailing edge (DTE) device 240. Each DTE device 240 is slideable along an aft surface of the trailing edge 210 between a stowed position and a fully deployed position. When stowed, the DTE device 240 is entirely within the trailing edge 210. When deployed fully or partially, the DTE device 240 extends beneath a lower surface of the trailing edge 210 to increases lift over draft of the wing 130.

    [0014] Chord length of the DTE device 240 may be between about 1% and 6% of chord length of the wing 130. In some configurations, the DTE device 240 may have a chord length between about four and six inches.

    [0015] Each DTE device 240 may be mounted to either a fixed surface 220 of the trailing edge 210 or a moveable flight control surface 230 of the trailing edge 210. In some wing configurations, multiple DTE devices 240 may be mounted to a fixed surface 220 and/or a moveable flight control surface 230.

    [0016] Reference is now made to FIGS. 3A and 3B, which illustrate an example of a wing 130 including a moveable flight control surface 230 and a DTE device 240 mounted to the moveable flight control surface 230. The DTE device 240 includes a stiffened panel 310. In some configurations, such as the configuration illustrated in FIGS 3A and 3B, the stiffened panel 310 is curved. In other configurations, the stiffened panel may be straight (see, e.g., FIG. 7).

    [0017] The moveable flight control surface 230 also includes a cover 315 for the DTE device 240. The cover 315 provides a sliding surface for the DTE device 240.

    [0018] An actuator assembly 320 may be utilized to slide the trailing edge device 240 between the stowed and deployed positions. The actuator assembly 320 may control the DTE device 240 independently of the moveable flight control surface 230. In some configurations, the actuator assembly 320 may include an actuator and linkage. In other configurations, the actuator assembly 320 may include an actuator alone. The actuator may be pneumatic, hydraulic, or electromechanical, and it may be located in a wing box 330 of the wing 130.

    [0019] FIG. 3A shows the DTE device 240 in a fully deployed position. By way of example, FIG. 3A shows the DTE device 240 with a maximum divergence angle (α) of about 15 degrees.

    [0020] The stiffened panel 310 may have a curvature whereby the divergence angle (α) of the DTE device 240 varies as the DTE device 240 is being deployed. For instance, the DTE device 240 has a maximum divergence angle (α) when fully deployed, and a smaller divergence angle (α) when partially deployed.

    [0021] FIG. 3B shows the DTE device 240 in the stowed position. The DTE device 240 is located entirely inside the moveable flight control surface 230 and, therefore, does not affect L/D of the wing 130.

    [0022] The DTE device 240 may be stowed to avoid exposure to high loading. As a result, a wing 130 including the DTE device 240 may have lighter wing structures than a wing including a fixed divergent trailing edge device. The lighter structures, in turn, lead to weight and fuel savings. Yet the DTE device 240 offers the same L/D advantage as a fixed divergent trailing edge device.

    [0023] Because the DTE device 240 is slideable instead of hinged, air loads are mostly carried through the wing 130. As a result, the DTE device 240 avoids issues inherent in hinged devices, such as issues with stiffness and torsional loads. The DTE device 240 also avoids free surface and flutter problems in the event the actuator assembly 320 fails.

    [0024] Moreover, since the air loads are carried mostly by the wing 130, the actuator assembly 320 may be configured primarily to overcome friction forces associated with sliding the DTE device 240. As a result, size of the actuator assembly 320 may be reduced to the point where it can be located entirely within the wing box 330. Advantageously, a fairing is not used to cover the actuator assembly 320, whereby collateral impact associated with the fairing is avoided.

    [0025] Reference is now made to FIG. 4, which illustrates an example of a trailing edge 210 and a DTE device 240 that is deployed. An upper surface 410 of the DTE device 240 is visible. The upper surface 410 has a plurality of ribs 420, which extend in a chordwise direction. The ribs 420 provide chordwise stiffness of the DTE device 240. The ribs 420 of the DTE device 240 make contact with the aft lower surface 430 of the trailing edge 210. Upward flight loads on the DTE device 240 are transmitted by the ribs 420 to the trailing edge 210 and are reacted by the wing 130.

    [0026] Additional reference is now made to FIG. 5, which illustrates ribs 510 on an aft lower surface of the trailing edge 210. These ribs 510 extend in a chordwise direction. In some configurations, the ribs 510 on the after lower surface of the trailing edge device 210 may be interlocked with ribs on the upper surface of the DTE device 240.

    [0027] FIG. 3C shows a configuration in which ribs 340 on the upper surface of the DTE device 240 are interlocked with ribs 350 on an aft lower surface of the trailing edge 210. These interlocked ribs 340 and 350 provide chordwise stiffness and prevent jamming when loads are not uniform spanwise. With these loads paths, the risk of flutter is reduced.

    [0028] Returning to FIG. 5, a cover 520 over a lower surface of the DTE device 240 provides a curved sliding surface for the DTE device 240. The cover 520 may also react air loads. For instance, the cover 520 may react a down load on the DTE device 240. The cover 520 may be fastened to the trailing edge 210 by fasteners 530. The fasteners 530 extend through slots 540 in the DTE device 240 and may limit lateral movement of the DTE device 240.

    [0029] Reference is now made to FIG. 6. In some examples not forming part of the claimed invention, a cover 610 may be part of the trailing edge 210. In the configuration shown in FIG. 6, the DTE device 240 slides along a surface 622 of a lower portion 620 the trailing edge 210. Fasteners 630 fasten the cover 610 to the lower portion 620. The fasteners 630 extend through slots 640 in the DTE device 240 and may limit lateral movement of the DTE device 240.

    [0030] Although the DTE devices 240 in FIGS. 3A, 3B, 4, 5 and 6 are all shown with curved stiffened panels, the DTE device 240 is not so limited. For instance, the DTE device 240 may include a stiffened panel that is substantially straight

    [0031] Reference is made to FIG. 7, which illustrates a DTE device 240 that includes a substantially straight stiffened panel 710. An actuator assembly 320 including an actuator 720 and an actuator linkage 730 move the DTE device 240 between a stowed position and a fully deployed position. When deployed, the DTE device 240 has a fixed divergence angle (α). When stowed, the DTE device 240 is contained entirely within the trailing edge 210.

    [0032] The actuator linkage 730 is along the direction of travel of the DTE device 240, which is mostly normal to the air load direction. Sized to overcome friction forces associated with sliding the DTE device 240, the actuator 720 and the actuator linkage 730 may be located entirely within the trailing edge 210.

    [0033] Reference is now made to FIG. 8A, which illustrates an example of a wing 130 including a wing box 810, a leading edge 820, and a trailing edge 210. The trailing edge 210 includes moveable flight control surfaces such as an inboard flap 830, flaperon 832, outboard flap 834, and aileron 836. The trailing edge 210 further includes a fixed surface including a tip 838.

    [0034] The wing 130 further includes a plurality of DTE devices 240. The surfaces 830 to 838 of the trailing edge 210 may include zero, one or multiple DTE devices 240. In the configuration shows in FIG. 8A, the tip 838 has no DTE devices 240, the flaperon 832 has a single DTE device 240, the inboard flap 830 has multiple DTE devices 240, the outboard flap 834 has multiple DTE devices 240, and the aileron 836 has multiple DTE devices 240. In another configuration, DTE devices 240 may be included from the root of the trailing edge 210 all the way out to the tip 838.

    [0035] Each DTE device 240 is slideable between a stowed position and a fully deployed position. The DTE devices 240 may be stowed entirely within their respective surfaces of the trailing edge 210. The DTE devices 240 may be deployed fully or partially under their respective surfaces of the trailing edge 210.

    [0036] Each of the DTE devices 240 may be provided with an actuator for independent control. Each actuator may be housed within its respective trailing edge surface 830-838.

    [0037] For example, FIG. 8B illustrates a portion of the aileron 836 and a rear spar 812 of the wing box 810. Each of the DTE devices 240 may be independently controllable. For instance, each trailing edge device 240 may be provided with an actuator 840 that is housed with the aileron 836.

    [0038] Reference is now made to FIG. 9, which illustrates a method of enhancing performance of an aircraft. The method includes selectively sliding one or more divergent tailing edge devices along a trailing edge of each aircraft wing to reduce lift over drag (L/D) of each wing (block 910). For example the DTE devices may be deployed to reduce drag and/or alleviate load. Any divergent trailing edge devices that are not deployed are stowed entirely within the trailing edges (block 920).

    [0039] Deploying selected DTE devices during different phases of the flight is advantageous. Depending on wing loading due to gross weight, center of gravity, speed and altitude, the DTE devices may be scheduled to deploy to optimize wing loading and aerodynamic efficiency.


    Claims

    1. A wing (130) comprising:
    a trailing edge (210);

    a divergent trailing edge device (240) slideable along a surface of the trailing edge between a stowed position and a fully deployed position, the trailing edge device located entirely within the trailing edge when stowed, the trailing edge device increasing lift over drag of the wing when deployed; and.

    a cover (315, 520) on a lower surface of the divergent trailing edge device, the cover providing a sliding surface for the divergent trailing edge device.


     
    2. The wing (130) of claim 1, wherein the divergent trailing edge device (240) extends beneath a lower surface of the trailing edge (210) when deployed.
     
    3. The wing (130) of any preceding claim, wherein the divergent trailing edge device (240) is mounted to a moveable flight control surface of the trailing edge, or
    a fixed surface of the trailing edge.
     
    4. The wing (130) of claims 1 or 2, wherein the divergent trailing edge device (240) has a divergence angle that varies as the device is being deployed.
     
    5. The wing (130) of any of claims 1 to 3, further comprising an actuator assembly (320) contained entirely within the trailing edge (210) for sliding the divergent trailing edge device (240).
     
    6. The wing (130) of any of claims 1 to 4, wherein the divergent trailing edge device (240) includes a stiffened curved panel (310).
     
    7. The wing (130) of any of claims 1 to 4, wherein the trailing edge device (240) includes a stiffened panel (710) that is substantially straight.
     
    8. The wing (130) of any preceding claim, wherein an upper surface (410) of the divergent trailing edge device (240) includes ribs (340, 420) that make contact with an aft lower surface of the trailing edge.
     
    9. The wing (130) of claim 8, wherein the aft lower surface of the trailing edge (210) also has ribs (350), which interlock with the ribs (340) of the trailing edge device (240).
     
    10. The wing (130) of any one of claims 1 to 9, wherein chord length of the trailing edge device (240) is between about 1% and 6% of chord length of the wing.
     
    11. The wing (130) of any preceding claim, further comprising at least one additional divergent trailing edge device (240) slidable along the aft surface of the trailing edge, each additional divergent trailing edge device slideable between a stowed position and a deployed position and a plurality of actuators for independent control of each divergent trailing edge device.
     


    Ansprüche

    1. Flügel (130) mit:

    einer Hinterkante (210);

    einer divergenten Hinterkantenvorrichtung (240), die entlang einer Oberfläche der Hinterkante zwischen einer eingefahrenen Position und einer vollständig ausgefahrenen Position verschiebbar ist, wobei die Hinterkantenvorrichtung im eingefahrenen Zustand vollständig innerhalb der Hinterkante angeordnet ist, wobei die Hinterkantenvorrichtung im ausgefahrenen Zustand das Auftriebs-Widerstandsverhältnis des Flügels erhöht; und

    einer Abdeckung (315, 520) auf einer Unterseite der divergierenden Hinterkantenvorrichtung, wobei die Abdeckung eine Gleitfläche für die divergierende Hinterkantenvorrichtung bildet.


     
    2. Flügel (130) nach Anspruch 1, bei dem sich die divergierende Hinterkantenvorrichtung (240) im ausgefahrenen Zustand unter einer Unterseite der Hinterkante (210) erstreckt.
     
    3. Flügel (130) nach einem der vorhergehenden Ansprüche, bei dem die divergierende Hinterkantenvorrichtung (240) an einer beweglichen Flugsteuerfläche der Hinterkante oder einer festen Fläche der Hinterkante montiert ist.
     
    4. Flügel (130) nach Anspruch 1 oder 2, bei dem die divergierende Hinterkantenvorrichtung (240) einen Divergenzwinkel aufweist, der sich beim Ausfahren der Vorrichtung ändert.
     
    5. Flügel (130) nach einem der Ansprüche 1 bis 3, ferner mit einer vollständig in der Hinterkante (210) enthaltenen Stellgliedanordnung (320) zum Verschieben der divergenten Hinterkantenvorrichtung (240).
     
    6. Flügel (130) nach einem der Ansprüche 1 bis 4, bei dem die divergente Hinterkantenvorrichtung (240) eine versteifte, gekrümmte Platte (310) aufweist.
     
    7. Flügel (130) nach einem der Ansprüche 1 bis 4, bei dem die Hinterkantenvorrichtung (240) eine versteifte Platte (710) aufweist, die im Wesentlichen gerade ist.
     
    8. Flügel (130) nach einem der vorhergehenden Ansprüche, bei dem eine Oberseite (410) der divergierenden Hinterkantenvorrichtung (240) Rippen (340, 420) aufweist, die mit einer hinteren Unterseite der Hinterkante in Kontakt kommen.
     
    9. Flügel (130) nach Anspruch 8, bei dem die hintere Unterseite der Hinterkante (210) auch Rippen (350) aufweist, die mit den Rippen (340) der Hinterkantenvorrichtung (240) ineinander greifen.
     
    10. Flügel (130) nach einem der Ansprüche 1 bis 9, bei dem die Sehnenlänge der Hinterkantenvorrichtung (240) zwischen etwa 1% und 6% der Sehnenlänge des Flügels beträgt.
     
    11. Flügel (130) nach einem der vorhergehenden Ansprüche, ferner mit mindestens einer zusätzlichen divergierenden Hinterkantenvorrichtung (240), die entlang der hinteren Fläche der Hinterkante verschiebbar ist, wobei jede zusätzliche divergierende Hinterkantenvorrichtung zwischen einer eingefahrenen Position und einer ausgefahrenen Position verschiebbar ist, und einer Mehrzahl von Stellgliedern zur unabhängigen Steuerung jeder divergierenden Hinterkantenvorrichtung.
     


    Revendications

    1. Aile (130) comprenant :

    un bord de fuite (210) ;

    un dispositif de bord de fuite divergent (240) pouvant coulisser le long d'une surface du bord de fuite entre une position rangée et une position complètement déployée, le dispositif de bord de fuite étant entièrement situé dans le bord de fuite lorsqu'il est rangé, le dispositif de bord de fuite augmentant la finesse aérodynamique de l'aile lorsqu'il est déployé ; et

    un couvercle (315, 520) sur une surface inférieure du dispositif de bord de fuite divergent, le couvercle fournissant une surface de glissement pour le dispositif de bord de fuite divergent.


     
    2. Aile (130) selon la revendication 1, dans laquelle le dispositif de bord de fuite divergent (240) s'étend au-dessous d'une surface inférieure du bord de fuite (210) lorsqu'il est déployé.
     
    3. Aile (130) selon l'une quelconque des revendications précédentes, dans laquelle le dispositif de bord de fuite divergent (240) est monté sur une surface de commande de vol mobile du bord de fuite, ou
    sur une surface fixe du bord de fuite.
     
    4. Aile (130) selon la revendication 1 ou 2, dans laquelle le dispositif de bord de fuite divergent (240) a un angle de divergence qui varie lorsque le dispositif est en cours de déploiement.
     
    5. Aile (130) selon l'une quelconque des revendications 1 à 3, comprenant en outre un ensemble actionneur (320) contenu entièrement à l'intérieur du bord de fuite (210) pour un coulissement du dispositif de bord de fuite divergent (240).
     
    6. Aile (130) selon l'une quelconque des revendications 1 à 4, dans laquelle le dispositif de bord de fuite divergent (240) comprend un panneau incurvé renforcé (310).
     
    7. Aile (130) selon l'une quelconque des revendications 1 à 4, dans laquelle le dispositif de bord de fuite (240) comprend un panneau renforcé (710) qui est sensiblement droit.
     
    8. Aile (130) selon l'une quelconque des revendications précédentes, dans laquelle une surface supérieure (410) du dispositif de bord de fuite divergent (240) comprend des nervures (340, 420) qui viennent en contact avec une surface inférieure arrière du bord de fuite.
     
    9. Aile (130) selon la revendication 8, dans laquelle la surface inférieure arrière du bord de fuite (210) présente également des nervures (350) qui se verrouillent mutuellement avec les nervures (340) du dispositif de bord de fuite (240).
     
    10. Aile (130) selon l'une quelconque des revendications 1 à 9, dans laquelle la longueur de corde du dispositif de bord de fuite (240) est comprise entre environ 1 % et 6 % de la longueur de corde de l'aile.
     
    11. Aile (130) selon l'une quelconque des revendications précédentes, comprenant en outre au moins un dispositif de bord de fuite divergent supplémentaire (240) pouvant coulisser le long de la surface arrière du bord de fuite, chaque dispositif de bord de fuite divergent supplémentaire pouvant coulisser entre une position rangée et une position déployée, et une pluralité d'actionneurs pour une commande indépendante de chaque dispositif de bord de fuite divergent.
     




    Drawing
























    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description