London Underground 1992 Stock & City line, which until 1994 was part of the national railway network, and became their Class 482. When this line passed to London Underground at the start of the process to privatise British Rail on 1 April 1994, these units also passed to London Underground. The vehicles are essentially identical to those used on the Central line; the main difference being that trip-cocks are used for protection instead of ATO/ATP. Transport for London and Metronet closed the Waterloo & City line for five months from April to September 2006 to allow major upgrade work on the tunnels and rolling
London Underground G Stock London Underground G Stock The G Stock were 50 electric multiple unit train carriages built for the District Railway in 1923 by Gloucester RC&W. They operated on the District line of the London Underground until 1971 (with most cars being withdrawn in the early 1960s). The G Stock was built to allow the scrapping of some of wooden-built B Stock trailer cars which were in poor condition. Some steel-framed B Stock motor cars were converted to trailers, themselves being replaced by new G Stock motorcars. The G Stock consisted entirely of motor cars, all built with a clerestory roof similar