The Circle line is a spiral-shaped London Underground line, running from Hammersmith in the west to Edgware Road and then looping around central London back to Edgware Road. The railway is below ground in the central section and on the loop east of Paddington. Unlike London's deep-level lines, the Circle line tunnels are just below the surface and are of similar size to those on British main lines. Printed in yellow on the Tube map, the 17-mile (27 km) line serves 36 stations, including most of London's main line termini. Almost all of the route, and all the stations, are shared with one or more of the three other sub-surface lines, namely the District, Hammersmith & City and Metropolitan lines. On the Circle and Hammersmith & City lines combined, over 141 million passenger journeys were recorded in 2019.
The London Underground 1973 Stock is a type of rolling stock used on the Piccadilly line of the London Underground. It was introduced into service in 1975 with the extension of the line to Hatton Cross, followed by a further extension to Heathrow Central in 1977. A total of 86 six-car trains were built.
London Underground rolling stock includes the electric multiple-unit trains used on the London Underground. These come in two sizes, smaller deep-level tube trains and larger sub-surface trains of a similar size to those on British main lines, both running on standard gauge tracks. New trains are designed for the maximum number of standing passengers and for speed of access to the cars.
The British Rail Class 485 and British Rail Class 486 electrical multiple units were originally built for the London Electric Railway from 1923-31 as its 'Standard' tube stock. They were purchased by British Rail in 1967 and transported to the Isle of Wight to work 'mainline' services on the newly electrified Ryde to Shanklin line, where they worked for an additional quarter of a century. At the time of their purchase the units had already worked for over 40 years on the London Underground, but their introduction allowed the last steam locomotives on the line to be withdrawn.
The Standard Stock title was applied to a variety of Tube stock built between 1923 and 1934, all of which shared the same basic characteristics, but with some detailed differences. This design is sometimes referred to as 1923 Tube Stock, 1923 Stock, or Pre 1938 Stock. Most of the Standard Stock was built to replace the first generation of "Gate Stock" Tube trains or to provide additional trains for extensions built in the 1920s and early 1930s. Standard Stock cars consisted of motor cars, with a driver's cab, behind which was a "switch compartment" occupying approximately one-third of the length of the car, plus trailer cars and "control trailers", with a driving cab but no motor. All were equipped with air operated sliding doors. The guard's door on the earlier trains was a manually operated, inward-opening hinged door.
The London Underground R Stock electric multiple units were used on London Underground's District line from 1949 to 1983. Composed of new cars and converted Q38 Stock trailers, the cars were built and converted in three batches between 1949 and 1959. The cars were driving motors (DM) or non-driving motors (NDM), there being no unpowered trailers. The second batch, introduced in 1952, was constructed from aluminium, saving weight and one train was left unpainted as an experiment. Considered a success, trains were left unpainted or painted white or grey to match in 1963–68. Originally designed to operate in trains with six off-peak and eight cars during peak hours, the trains were reformed as fixed seven-car trains in 1971. R Stock trains were replaced by the D78 Stock and withdrawn between 1981 and 1983.
The Q Stock consisted of various District line trains, built from 1923 until the mid-1930s, originally built with manually operated sliding doors. Following conversion to air operated doors, the trains became collectively known as Q Stock. Given that five different types of rolling stock were converted to Q Stock, the resulting hybrid trains looked bizarre - with the older carriages having flat sides and clerestory roofs, whilst the Q38 had flared sides at floor level.
The London Underground O and P Stock electric multiple units were used on the London Underground from 1937 to 1981. O Stock trains were built for the Hammersmith & City line, using metadyne control equipment with regenerative braking, but the trains were made up entirely of motor cars and this caused technical problems with the traction supply so trailer cars were added. P Stock cars were built to run together with the O Stock cars now surplus on Metropolitan line Uxbridge services. The trains had air-operated sliding doors under control of the guard; the O Stock with controls in the cab whereas the P Stock controls in the trailing end of the motor cars. The P Stock was introduced with first class accommodation, but this was withdrawn in 1940.
The London Underground 1962 Stock was a type of London Underground tube train built for use on the Central line. They were used on the Central line between 1962 and 1995, with some later being transferred to the Northern line where they were used until 1999.
The London Underground A60 and A62 Stock, commonly referred to as A Stock, was a type of sub-surface rolling stock which operated on the Metropolitan line of the London Underground from 12 June 1961 to 26 September 2012, and on the East London line from 1977 until 22 December 2007, when it closed to be converted into London Overground.
The London Underground D78 Stock, commonly referred to as D Stock, was a type of sub-surface rolling stock which operated on the District line of the London Underground, except on the Wimbledon to Edgware Road service. The first units were withdrawn in January 2015 with the last withdrawn on 21 April 2017.
The London Underground 1983 Stock was a class of electric multiple unit built by Metro-Cammell for use on London Underground's Jubilee line.
The London Underground 1972 Stock is a type of rolling stock used on the London Underground. The 1972 Stock was originally ordered to make up the shortfall in trains on the Northern line's 1959 Tube Stock fleet, but is currently used on the Bakerloo line. Following the withdrawal of the British Rail Class 483 EMUs in 2021, the 1972 Stock are now the oldest EMUs in passenger service in the United Kingdom. A total of 63 seven-car trains were built in two separate batches.
The London Underground 1967 Stock was a type of deep-level train that operated on the Victoria line of the London Underground from the line's opening on 1 September 1968 until 30 June 2011. It was also used on the Central line between Woodford and Hainault between 21 February 1968 and 1984, as the same automatic train operation (ATO) system was used on both lines.
The London Underground 1996 Stock is a type of rolling stock used on the Jubilee line of the London Underground. The trains were built by GEC Alsthom-Metro-Cammell and entered service in 1997. They are similar to the 1995 Stock used on the Northern line.
The London Underground S7 and S8 Stock, commonly referred to as S Stock, is a type of passenger train running on the London Underground's subsurface lines since 2010. Manufactured by Bombardier Transportation's Derby Litchurch Lane Works, the S Stock was ordered to replace the A60, A62, C69, C77 and D78 stock on the Metropolitan, District, Hammersmith & City, and Circle lines, which all dated from the 1960s and 1970s.
Rolling stock used on the London Underground and its constituent companies has been classified using a number of schemes. This page explains the principal systems for the rolling stock of the Central London Railway (CLR), the Underground Electric Railways Company of London (UERL), the District Railway (DR) and the Metropolitan Railway (MR). For information about individual classes of locomotives and other rolling stock, see London Underground rolling stock.
The London Underground 1956 Stock consisted of three prototype units built before mass production of the 1959 tube stock. These units were tested on the Piccadilly line and remained in service after production trains were introduced. Later they were transferred to the Northern line, but in 1995 they were replaced as non-standard by 1962 Stock cascaded from the Central line.
Departmental locomotives on the London Underground consist of vehicles of a number of types which are used for engineering purposes. These include battery locomotives, diesel locomotives, electric locomotives, sleet locomotives, pilot motor cars and ballast motor cars. Details of the first four types are covered elsewhere. Pilot motor cars and ballast motor cars are generally vehicles which have been withdrawn from passenger service, but continue to be used by the engineering department. Pilot motor cars are used to move other vehicles around the system, while ballast motor cars are used to haul ballast trains and engineering trains.
Acton Works is a London Underground maintenance facility in West London, England. It is accessed from the District line and Piccadilly line tracks to the east of Acton Town station, and was opened in 1922. It was responsible for the overhaul of rolling stock, and gradually took on this role for more lines, until the formation of the London Passenger Transport Board in 1933, when all major overhauls of underground vehicles were carried out at the works. By 1985, when rolling stock had become more reliable and maintenance intervals had increased, this function was devolved to depots on each line. Subsequently, Acton continued to overhaul major items after they had been removed from trains at the depots, and tendered for work, which included the conversion of the A60 Stock to One Person Operation. It is likely to be reorganised and expanded to house the departments displaced from Lillie Bridge Depot which is being demolished as part of the redevelopment of Earls Court Exhibition Centre.
