Airframe for an air vehicle

1. An airframe for an air vehicle comprising an outer skin layer and a support layer defining said airframe of said air vehicle, wherein said outer skin layer is magnetically coupled during flight to said support layer;

wherein said support layer is provided with a plurality of support columns extending outwardly from the support layer, the outer skin layer being both supported by the plurality of support columns and magnetically coupled to the support layer thereby; and

wherein said plurality of support columns are provided with one or more electromagnets located in or on the plurality of support columns and said outer skin layer comprises a magnetically susceptible material, the outer skin layer being magnetically coupled to the support layer by the one or more electromagnets and the magnetically susceptible material.

2. The airframe according to claim 1 , wherein the magnetically susceptible material is embedded in, or incorporated by, the outer skin layer.

3. The airframe according to claim 2 , wherein the magnetically susceptible material comprises an array of ferromagnetic sheet material inserts embedded in or otherwise provided in or on said outer skin layer.

4. The airframe according to claim 2 , wherein the magnetically susceptible material comprises magnetically susceptible particles incorporated in or on the outer skin layer.

5. The airframe according to claim 4 , wherein the magnetically susceptible material comprises a distributed particulate array.

6. The airframe according to claim 2 , wherein the magnetically susceptible material comprises a permanently magnetic material.

7. The airframe according to claim 1 , wherein said one or more electromagnets comprise superconducting windings.

8. The airframe according to claim 1 , further comprising a means for supplying power to said one or more electromagnets to generate an attracting force relative to said magnetically susceptible material so as to couple said outer skin layer to said support layer.

9. The airframe according to claim 8 , further comprising a means for selectively suspending or reversing said power supplied to said one or more electromagnets so as to release said outer skin layer from said support layer.

10. The airframe according to claim 8 , wherein the plurality of support columns comprise rigid elongate cylindrical or tubular members and the one or more electromagnets are contained in the support columns.

11. An air vehicle including the airframe according to claim 1 .

12. A method of manufacturing an airframe for an air vehicle, the method comprising the steps of:

providing a support layer defining said airframe of said air vehicle and including a plurality of support columns extending outwardly from the support layer;

providing one or more electromagnets located in or on the plurality of support columns;

providing an outer skin layer comprising a magnetically susceptible material;

and magnetically coupling said outer skin layer to said support layer by the one or more electromagnets and the magnetically susceptible material, said magnetic coupling to be sustained during flight.