Automation of the London Underground Automation of the London Underground Automation of London Underground rolling stock has been partially implemented since the introduction of automatic train operation on the Hainault to Woodford section of the Central line in 1964. It is currently in use on four lines. Transport for London plans to extend this to other lines by 2022. Partially automated trains using Automatic Train Operation (ATO) have been used on passenger services on the Victoria line since 1968. The side doors to the driver's cab were sealed, so that access was normally through the passenger saloon. Since the trains were to be operated by
London Underground with smaller trains that run in two circular tunnels ("tubes") with a diameter about . These lines have the exclusive use of a pair of tracks, except for the Piccadilly line, which shares track with the District line between Acton Town and Hanger Lane Junction and with the Metropolitan line between Rayners Lane and Uxbridge; and the Bakerloo line, which shares track with London Overground services north of Queen's Park. Fifty-five per cent of the system runs on the surface. There are of cut-and-cover tunnel and of tube tunnel. Many of the central London underground stations on deep-level tube routes