Thanks Sasha & nanettealsop & Helen, it is a very strange place along some of the unused lines and tunnels, I'm lucky to know someone kind enough to show me places that the public are not usually permitted, glad you like the image too. The roundel (london underground symbol) was straight forward to make, just an ellipse and a line.
Helen - What I did was duplicate the original black aeroplane clip art, re coloured one red and unticked it. Ran object edge on the black one and then clipwarp. I then moved the red one to the top and I think it was either overlay or multiply, then just a once over with AA's Assistant. I used the same method with the red frame too
I'm getting kind of clipwarp fever now, I look around at things to take a picture of so that I can add a twist to it