Wingtip extension for reducing wake vortices of aircraft

Patent metadata

Field	Value
Publication number	US-9545997-B2
Application number	US-74680608-A
Country	US
Kind code	B2
Filing date	Dec 8, 2008
Priority date	Dec 10, 2007
Publication date	Jan 17, 2017
Grant date	Jan 17, 2017

Abstract

The invention relates to a wingtip extension comprising a leading edge and a trailing edge, which wingtip extension is affixable to an outer end of a wing, wherein the leading edge, at least in some sections, is essentially straight, and the straight section of the leading edge comprises a leading-edge sweep angle that exceeds the leading-edge sweep angle of the wing, and the local depth of the wingtip extension gradually decreases between a connecting region for connection to the wing and the outer end of the wingtip extension. By means of a wingtip extension according to the invention, in a delta wing a vortex burst region is positioned just behind the wingtip, as a result of which vortex burst region the cores of wingtip vortices burst and eventually become unstable, so that as a result of this the wake vortices of the aircraft can be reduced. The invention furthermore relates to a wing, comprising wingtip extensions according to the invention, as well as to an aircraft comprising such a wing.

First claim

The invention claimed is:

1. A wingtip extension for a wing of an aircraft for reducing of wake vortices, comprising:
a leading edge at least partially being substantially straight; and
a trailing edge configured to be affixable to a connection region of the wing;
wherein a straight section of the leading edge comprises a leading-edge sweep angle exceeding the leading-edge sweep angle of the wing;
wherein a local depth of the wingtip extension corresponds to a local depth of the wing in the connection region;
wherein a local depth of the wingtip extension gradually decreases between a connecting region for connection to the wing and the opposite end of the wingtip extension
wherein the wingtip is configured such that a wingtip vortex arising from the wingtip is influenced by a bursting vortex core such that the wingtip vortex starts to decay; and
wherein a cross-sectional profile of the wingtip extension is substantially flat or at least at the leading edge is tapered to a point.

2. The wingtip extension of claim 1 , wherein the trailing edge is essentially straight.

3. The wingtip extension of claim 1 , wherein the trailing edge extends so as to be substantially parallel to the trailing edge of the wing.

4. The wingtip extension of claim 1 , wherein the leading edge and the trailing edge converge in such a manner that an outer end of the wingtip extension forms a point.

5. The wingtip extension of claim 1 , wherein the leading edge and the trailing edge are spaced apart from each other at an outer end of the wingtip extension.

6. The wingtip extension of claim 1 , wherein the trailing edge comprises a trailing edge sweep angle larger than a trailing edge sweep angle of the wing.

7. The wingtip extension of claim 1 , wherein the wingtip extension comprises a positive distortion so that a local angle of attack of the wingtip extension increases towards the outside.

8. The wingtip extension of claim 1 , wherein the leading-edge sweep angle ranges from 40° to 75°.

9. The wingtip extension of claim 1 , wherein the leading-edge sweep angle is about 60°.

10. The wingtip extension of claim 1 , wherein the leading-edge sweep angle is about 70°.

11. An aircraft comprising first and second wings, each of first and second wings comprising a wingtip extension arranged at a connection region of the respective wing,
wherein the wingtip extension comprises:
a leading edge at least partially being substantially straight; and
a trailing edge configured to be affixable to a connection region of the wing;
wherein a straight section of the leading edge comprises a leading-edge sweep angle exceeding the leading-edge sweep angle of the wing;
wherein a local depth of the wingtip extension corresponds to a local depth of the wing in the connection region;
wherein a local depth of the wingtip extension gradually decreases between a connecting region for connection to the wing and the opposite end of the wingtip extension;
wherein the wingtip is configured such that a wingtip vortex arising from the wingtip is influenced by a bursting vortex core such that the wingtip vortex starts to decay; and
wherein a cross-sectional profile of the wingtip extension is substantially flat or at least at the leading edge is tapered to a point.

12. A method for reducing wake vortices of an aircraft, the method comprising:
affixing a wingtip extension to an outer edge of a wing of the aircraft;
wherein a leading edge of the wingtip extension is at least partially substantially straight and a trailing edge is affixed to a connection region of the wing and wherein a straight section of the leading edge comprises a leading-edge sweep angle exceeding a leading-edge sweep angle of the wing; and
causing a vortex to burst in a region between the leading edge and the trailing edge of the wingtip extension such that an arising wingtip vortex is influenced by the bursting core of the vortex to such an extent as to cause decay of the wingtip vortex.

13. The method of claim 12 , wherein the bursting the vortex in the region between the leading edge and the trailing edge occurs at angles of attack common during takeoff and landing of the aircraft.

14. The method of claim 12 , further comprising causing the core of the wingtip vortex to burst behind the wingtip.

15. The method of claim 12 , further comprising positively warping the wingtip extension.

Assignees

• Kelm Roland
• Airbus Operations Gmbh

Inventors

• Kelm Roland

Classifications

• Y02T50/164

  Cross-Sectional Technologies · mapped topic

• B64C23/065 Primary

  at the wing tips · CPC title

• Y02T50/10

  Drag reduction · CPC title

• B64C23/069 Primary

  using one or more wing tip airfoil devices, e.g. winglets, splines, wing tip fences or raked wingtips · CPC title