Two filming models of the XQR were made, to different scales. The puppet-scale cockpit set was adapted from the interior of "Thunderbird 4". As the lightning bolt effect could not be created in-studio, it was instead added during post-production via optical printing. The illusion of distant lightning bursts was created by flashing an arc welder, while the flames and smoke issuing from the crippled XQR were produced by Jetex fuel pellets attached to the side of the model that was facing away from the camera. For the crash scene, petrol gel explosives were detonated in the foreground to simulate the plane's destruction; the model was retained so that it could be re-used in later episodes. A shot of the reconstructed XQR making its final approach to Cloudbase was filmed but ultimately cut.