# US 10,501,170 B2 · Aircraft wing with a wing tip device and a strut > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,501,170 B2 - Document ID: US10501170B2 - Status: Granted - Kind: B2 - Application number: 15/301,489 - Filed: 2015-04-02 - Published: 2017-02-02 - Granted: 2019-12-10 - Earliest claimed: 2014-04-04 - Assignees: Airbus Operations GmbH - Applicants: Airbus Operations Limited - Inventors: Christopher Lynas; Robert Thompson; Llifon Williams; John Hobday - Web page: https://patentgrep.com/patent/US10501170B2 ## CPC - B64C 23/072: {the wing tip airfoil devices being moveable in their entirety} - B64C 3/546: {by foldable elements} - B64C 3/185: {Spars} - B64C 3/54: Varying in area - Y02T 50/10: Drag reduction - B64C: AEROPLANES; HELICOPTERS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract An aircraft wing (1) has a wing tip device (3) joined thereto. The root (7) of the wing tip device (3) is joined to the tip of the wing (1) at a first connection (11). An external strut (9) extends between the wing (1) and the wing tip device (3), the strut (9) being joined to the wing (1) at a second connection (13). The second connection (13) is inboard of the first connection, such that loadings on the wing tip device (3) generated during use, are transferred, via the strut (9), to a location on the wing (1) that is inboard of where the root (7) of the wing tip device (3) is joined to the tip of the wing. ## Claims ### Claim 1 A primary aircraft wing having a wing tip device joined thereto, wherein the root of the wing tip device is joined to a tip of the primary wing at a first connection, wherein a leading edge of the wing tip device is aligned along a spanwise direction with a leading edge of the primary wing across the first connection, and wherein an external strut extends between the primary wing and the wing tip device, the external strut being joined to the primary wing at a second connection, the second connection being inboard of the first connection and outboard of a root of the primary wing, such that loadings on the wing tip device generated during flight, are transferred, via the external strut, to a location on the primary wing that is inboard of where the root of the wing tip device is joined to the tip of the primary wing wherein the wing tip device is configured to pivot about the first connection, and the second connection and an end of the external strut at the second connection are configured to translate in the spanwise direction along the fixed primary wing as the wing tip device pivots about the first connection. ### Claim 2 (depends on 1) The aircraft wing according to claim 1, wherein the primary wing was originally designed not to have the wing tip device, the wing tip device having been retro-fitted or forward-fitted to the primary wing. ### Claim 3 (depends on 1) The primary aircraft wing according to claim 1, wherein an assembly comprising the primary wing, the external strut and the wing tip device is statically determinate. ### Claim 4 (depends on 1) The primary aircraft wing according to claim 1, wherein the wing tip device is moveable about the first connection between (i) a flight configuration for use during all flight operations during which the external strut is exposed to air flowing over the primary wing, and (ii) a ground configuration for use during ground-based operations, in which ground configuration the wing tip device is folded about the first connection such that the span of the aircraft is reduced. ### Claim 5 (depends on 1) The primary aircraft wing of claim 1, wherein the second connection is joined to a position on the primary wing closer to the wing tip device than to the root of the primary wing. ### Claim 6 (depends on 1) The primary aircraft wing of claim 1, wherein the primary wing is a mono-wing. ### Claim 7 (depends on 1) The primary aircraft wing of claim 1, wherein the trailing edge of the fixed primary wing is aligned in the spanwise direction with a trailing edge of the wing tip device across the first connection. ### Claim 8 (depends on 1) The primary aircraft wing of claim 1, wherein the second connection between the fixed primary wing and the external strut is closer to the trailing edge of the fixed primary wing than to the leading edge of the fixed primary wing. ### Claim 9 (depends on 1) The primary aircraft wing according to claim 1, wherein the first connection is unsuitable for transferring the loadings on the wing tip device to the primary wing, in the absence of the external strut. ### Claim 10 (depends on 9) The primary aircraft wing according to claim 9, wherein the first connection is substantially unable to support a bending moment across the first connection, wherein the bending moment is applied by the wing tip device in absence of the external strut. ### Claim 11 (depends on 1) The primary aircraft wing according to claim 1, wherein the external strut is joined to the wing tip device at a third connection. ### Claim 12 (depends on 11) The primary aircraft wing of claim 11, wherein the external strut is bowed between the second and third connections in a direction outward from the fixed primary wing and the wing tip device. ### Claim 13 A method of modifying a primary wing by fitting a wing tip device, the method comprising the steps of: joining a root of the wing tip device to a tip of the primary wing at a first connection, aligning, along a spanwise direction, a leading edge of the wing tip device with a leading edge of the primary wing across the first connection, and fitting an external strut extending between the primary wing and the wing tip device, the external strut being connected to the primary wing at a second connection, the second connection being inboard of the first connection and outboard of a root of the primary wing, such that loadings on the wing tip device generated during use, are transferred, via the external strut, to a location on the primary wing that is inboard of where the root of the wing tip device is joined to the tip of the primary wing, wherein the external strut is exposed to air flowing across the primary wing during all flight operations of the primary wing. ### Claim 14 (depends on 13) The method according to claim 13, wherein the wing tip device is retro-fitted onto the primary wing that was not originally designed to receive the wing tip device, and the method further comprises the step of removing a pre-existing structure from the primary wing, prior to joining the root of the wing tip device to the tip of the primary wing at the first connection. ### Claim 15 (depends on 13) The method according to claim 13, wherein the wing tip device is forward-fitted onto the primary wing that was not originally designed to receive the wing tip device, and the method further comprises the step of manufacturing the tip of the primary wing to be suitable for joining to the root of the wing tip device at the first connection. ### Claim 16 (depends on 13) The method according to claim 13, wherein the wing tip device hangs below the first connection prior to the strut being fitted to extend between the primary wing and the wing tip device. ### Claim 17 (depends on 13) The method of claim 13, wherein the second connection is joined to a position on the primary wing closer to the wing tip device than to the root of the primary wing. ### Claim 18 (depends on 13) The method of claim 13, wherein the primary wing is a mono-wing. ### Claim 19 (depends on 13) The method of claim 13, further comprising aligning, along the spanwise direction, a trailing edge of the wing tip device with a trailing edge of the primary wing across the first connection. ### Claim 20 (depends on 13) The method of claim 13, wherein the wing tip device is configured to pivot about the first connection, and the second connection and an end of the external strut at the second connection are configured to translate in the spanwise direction along the fixed primary wing as the wing tip device pivots about the first connection. ### Claim 21 (depends on 13) The method of claim 13, wherein the second connection between the fixed primary wing and the wing tip device is closer to the trailing edge of the fixed primary wing than to the leading edge of the fixed primary wing. ### Claim 22 (depends on 13) The method of claim 13, wherein the external strut is bowed outward from the primary wing and the wing tip device. ### Claim 23 A primary aircraft wing comprising: a fixed primary wing having a leading edge, a trailing edge, a root and a wing tip opposite, along a spanwise direction, to the root; a wing tip device having a leading edge, a trailing edge and a root; a first connection connecting the wing tip of the fixed primary wing to the root of the wing tip device, wherein the leading edge of the fixed primary wing is aligned in the spanwise direction with the leading edge of the wing tip device across the first connection; and an external strut extending between the fixed primary wing and the wing tip device, wherein the external strut is joined to the fixed primary wing at a second connection outboard, along the spanwise direction, of the root of the fixed primary wing and inboard of the wing tip, and the external strut is exposed to air flowing across the primary wing during all flight operations of the primary wing. ### Claim 24 (depends on 23) The primary aircraft wing of claim 23, wherein the trailing edge of the fixed primary wing is aligned in the spanwise direction with the trailing edge of the wing tip device across the first connection. ### Claim 25 (depends on 23) The primary aircraft wing of claim 23, wherein the wing tip device is configured to pivot about the first connection, and the second connection and an end of the external strut at the second connection are configured to translate in the spanwise direction along the fixed primary wing as the wing tip device pivots about the first connection. ### Claim 26 (depends on 23) The primary aircraft wing of claim 23, wherein the second connection between the fixed primary wing and the wing tip device is closer to the trailing edge of the fixed primary wing than to the leading edge of the fixed primary wing. ### Claim 27 (depends on 23) The primary aircraft wing of claim 23, wherein the external strut is bowed between the second connection and wherein the external strut is joined to the wing tip device at a third connection that extends in a direction outward from the fixed primary wing and the wing tip device.