By far the bigger problem was how to portray the interior of the Lancaster fuselage from an angle that normally you cannot see because it is behind the outer skin and the radome suspended below the mid-upper gun turret.

The last time I visited the BBMF at RAF Coningsby I had taken a couple of photographs of the interior of their Lancaster, PA474. So I knew what it looked like – but from the wrong angle to use in my compilation.

Happily I was able to get their publications editor, Clive Rowley, who had commissioned the picture, to go and stick his camera in from the rear crew door to give me a better idea of the required perspective.

Once I had it clearer in my mind's eye, I then basically built the various pieces of equipment either by adapting the pictures to hand or simply creating elements from scratch - such as the outer and inner parts of the H2S radome, the ribs that frame the aircraft, and the pipework, wires, ammo boxes and runs.