
Visible crew/equipment: In the fourth part, as the mortally wounded fighter is falling against the back wheel of the cart, the camera is positioned low and its shot is panned upwards, revealing the top of the cyclorama, a large concave backcloth that has been pulled around the studio walls (presumably BBC Studio 1) to give the impression of daylight in these studio-shot but supposedly external scenes.
Answer: It was never destroyed on-screen; it was intact at the end of the TV movie, and destroyed by the start of the 2005 series. It was destroyed in the novel "The Ancestor Cell," but in a completely different manner to what happened in the series.
DaveJB