WING AIRFOIL STIFFENING FOR SOLAR POWERED AIRCRAFT

• US 20160167764A1
• Filed: 12/15/2014
• Published: 06/16/2016
• Est. Priority Date: 10/19/2011
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Grip, Robert Erik, Kutzmann, Aaron J., Rawdon, Blaine Knight
• Granted Patent: US 10,640,221 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B64C 3/18 Spars; Ribs; Stringers
• CPC Class Codes: B64C 3/182 Stringers, longerons
• CPC Class Codes: B64C 3/185 Spars
• CPC Class Codes: B64C 3/187 Ribs
• CPC Class Codes: B64C 3/22 Geodetic or other open-frame structures
• CPC Class Codes: B64C 3/26 Construction, shape, or attachment of separate skins, e.g. panels
• CPC Class Codes: B64D 27/24 using steam or spring force jet aircraft B64D27/16
• CPC Class Codes: B64D 27/353 using solar cells
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y02T 50/50 On board measures aiming to increase energy efficiency
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

A light-weight stiffened wing airfoil includes at least one wing segment (52). The wing segment comprises an upper (53b) and a lower skin assembly (53a), wherein each of the upper and lower skin assemblies incorporates a plurality of inwardly facing stringer grooves (74); a first rib (64-1) at a distal end of the wing segment and a second rib (64-2) at a proximal end of the wing segment; a plurality of rib trusses (70) extending from the first and second ribs to the opposing skin assembly (53); and a plurality of support members extending from the inwardly facing stringer grooves to the opposing skin assembly.

Claims

1. A light-weight stiffened wing airfoil including at least one wing segment (52), the wing segment comprising:

an upper (53b) and a lower skin assembly (53a), wherein each of the upper and lower skin assemblies incorporates a plurality of inwardly facing stringer grooves (74);

a first rib (64-1) at a distal end of the wing segment and a second rib (64-2) at a proximal end of the wing segment;

a plurality of rib trusses (70) extending from the first and second ribs to an opposing skin assembly (53); and

a plurality of support members extending from the inwardly facing stringer grooves to the opposing skin assembly.

2. The light-weight stiffened wing airfoil of claim 1, wherein the plurality of support members comprise rib support members (76a) that extend from the inwardly facing stringer grooves (74) to portions of the first rib (64-1) and the second rib (64-2) located on the opposing skin assembly (53).

3. The light-weight stiffened wing airfoil of claim 2, wherein the plurality of support members further comprise:

skin support members (76b) extending from the inwardly facing stringer grooves (74) to various points (86) on the opposing skin assembly (53) between the first rib (64-1) and the second rib (64-2).

4. The light-weight stiffened wing airfoil of claim 3, wherein each of the rib support members (76a) corresponds to one of the skin support members (76b).

5. The light-weight stiffened wing airfoil of claim 3, wherein the various points (86) of the opposing skin assembly (53) are evenly spaced between the first rib (64-1)and second rib (64-2).

6. The light-weight stiffened wing airfoil of claim 1, wherein at least some of the plurality of support members (76) comprise flexible wires or rigid rods.

7. The light-weight stiffened wing airfoil of claim 1, wherein at least one of the lower skin assembly (53a) and the upper skin assembly (53b) curves away from the other of the lower skin assembly and the upper skin assembly.

8. The light-weight stiffened wing airfoil of claim 7, wherein the at least one curved skin assembly is curved inward by tension supplied by at least some of the support members (76).

9. The light-weight stiffened wing airfoil of claim 1, wherein the support members (76) extending from the inwardly facing stringer grooves (74) of the lower skin assembly (53a) to the upper skin assembly (53b) comprise wires, and wherein the support members extending from the inwardly facing stringer groves of the upper skin assembly to the lower skin assembly comprise rigid rods.

10. The light-weight stiffened wing airfoil of claim 1, wherein a group of the plurality of support members (76) contact the inwardly facing stringer grooves (74) of the upper and lower skin assemblies (53) via a connector (88) in contact with a rib flange (90) of one of the first rib (64-1) or the second rib (64-2), or one or more of the inwardly facing stringer grooves (74).

11. The light-weight stiffened wing airfoil of claim 10, wherein at least one of the plurality of rib trusses (70) is mounted to the connector (88).

12. The light-weight stiffened wing airfoil of claim 10, wherein a blade (94) of the connector (88) contacts one of the upper (53b) and lower skin assemblies (53a).

13. The light-weight stiffened wing airfoil of claim 1, further comprising:

a solar panel (58) located on the upper skin assembly (53b) opposite the inwardly facing stringer grooves (74).

14. The light-weight stiffened wing airfoil of claim 1, wherein a portion of the plurality of support members (76c) attached to an aft portion (96) of one of the upper (53b) and lower skin assemblies (53a) comprise shape-memory alloy, wherein the portion of support members controls a shape of a trailing edge (98) of at least one of the upper and lower skin assemblies.

15. A method for stiffening a light-weight wing airfoil of a wing comprising:

bracing an upper skin assembly (53b) and a lower skin assembly (53a) of the light-weight wing airfoil by a first rib (64-1) located at a distal end of the light-weight wing airfoil and a second rib (64-2) located at a proximal end of the light-weight wing airfoil, wherein the first and second ribs are each supported by a plurality of rib trusses (70) extending between upper (64a) and lower rib caps (64b) of each of the first rib and the second rib; and

cross-bracing the light-weight wing airfoil by a plurality of wires, rigid rods, or both (76), wherein the plurality of wires, rigid rods, or both extend from one of the upper or lower rib caps of the first rib or the second rib to the opposing upper skin assembly or lower skin assembly.

16. The method of claim 15, wherein the cross-bracing further comprises:

stiffening the light-weight wing airfoil by a plurality of rib wires, rib rigid rods, or both (76a), wherein the rib wires, rib rigid rods, or both extend between the upper (64a) and the lower rib caps (64b) of each of the first (64-1) and second rib (64-2); and

stiffening the light-weight wing airfoil by a plurality of skin wires, skin rigid rods, or both (76b), wherein skin wires, skin rigid rods, or both extend from one of the upper or lower rib caps of the first rib or the second rib to various points (86) on the opposing upper skin assembly or the lower skin assembly between the first and second ribs.

17. The method of claim 15, wherein at least one of the lower skin assembly (53a) and the upper skin assembly (53b) curves away from the other of the lower skin assembly and the upper skin assembly.

18. The method of claim 15, wherein the cross-bracing further comprises:

stiffening the light-weight wing airfoil by a plurality of wires (76) extending from the lower rib cap (64b) of the first (64-1) or second rib (64-2) on the lower skin assembly (53a) to the upper skin assembly (53b); and

stiffening the light-weight wing airfoil by a plurality of rigid rods (76) extending from the upper rib cap (64a) of the first (64-1) or second rib (64-2) on the upper skin assembly (53b) to the lower skin assembly (53a).

19. The method of claim 15, wherein the cross-bracing further comprises:

attaching a group of the wires, rigid rods, or both (76), to at least one of the upper (64a) or the lower rib caps (64b) of the first (64-1) or second rib (64-2) via one or more holes (93) on a connector (88).

20. The method of claim 19, wherein the group of wires, rigid rods, or both (76), extend from the connector (88) outwardly in a radial configuration.

21. A method for assembling a stiffened light weight wing airfoil comprising:

attaching a plurality of rib trusses (70) to upper (64a) and lower rib caps (64b) of a first (64-1) and second rib (64-2) using a plurality of connectors (88);

bonding the first and second ribs to a proximal portion and a distal portion of one of an upper skin assembly (53b) or a lower skin assembly (53a);

fitting a plurality of support members (76a) between the plurality of connectors (88), wherein the plurality of support members extend from the upper rib cap of the first or second rib to the lower rib cap of the first or second rib; and

bonding the other of the upper skin assembly or the lower skin assembly to the first and second ribs.

22. The method of claim 21, wherein the fitting further comprises:

fitting a plurality of skin support members (76b) between the plurality of connectors (88) and various points (86) on at least one of the upper skin assembly (53b) and the lower skin assembly (53a).