The Central line is a London Underground line that runs through central London, from Epping, Essex, in the north-east to Ealing Broadway and West Ruislip in west London. Printed in red on the Tube map, the line serves 49 stations over 46 miles (74 km), making it the longest line on the Underground. It is one of only two lines on the Underground network to cross the Greater London boundary, the other being the Metropolitan line. One of London's deep-level railways, Central line trains are smaller than those on British main lines.
The District line is a London Underground line running from Upminster in the east and Edgware Road in the west to Earl's Court in west London, where it splits into multiple branches. One branch runs to Wimbledon in south-west London and a short branch, with a limited service, only runs for one stop to Kensington (Olympia). The main route continues west from Earl's Court to Turnham Green after which it divides again into two western branches, to Richmond and Ealing Broadway.
Acton Town is a London Underground station in the south-west corner of Acton, West London, in the London Borough of Ealing, close to the border with the London Borough of Hounslow. The station is served by the District and Piccadilly lines and is in Travelcard Zone 3. On the District line, it is between Chiswick Park and Ealing Common stations, and on the Piccadilly line it is between Hammersmith and Ealing Common on the Uxbridge branch & South Ealing on the Heathrow branch. Acton Town station was opened as Mill Hill Park on 1 July 1879 by the District Railway. It remained as a terminus until on 1 May 1883 and 23 June 1903 the DR opened two branches from Acton Town to Hounslow Town and Park Royal & Twyford Abbey respectively. On 4 July 1932 the Piccadilly line was extended to Acton Town. District line services to both the Hounslow and Uxbridge branches were withdrawn completely on 9 and 10 October 1964 after which operations were provided by the Piccadilly line alone.
Ealing Broadway is a major single-level interchange station located in Ealing, in the London Borough of Ealing, West London for London Underground services and also Elizabeth line services on the National Rail Great Western Main Line.
Ealing Common is a London Underground station on the Uxbridge branch of the Piccadilly line and on the Ealing Broadway branch of the District line. Eastbound, the next station is Acton Town; westbound, the next station is North Ealing on the Piccadilly line and Ealing Broadway on the District line. Here, the District and Piccadilly lines share the same pair of tracks through the station – the only other example where a deep level line and a sub surface line share the same pair of tracks is further up the Uxbridge branch, where the Piccadilly line shares tracks with the Metropolitan line from Rayners Lane to Uxbridge. It is the only station west of Acton Town to be served by both the Piccadilly and District lines.
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 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 Metropolitan District Railway, also known as the District Railway, was a passenger railway that served London, England, from 1868 to 1933. Established in 1864 to complete an "inner circle" of lines connecting railway termini in London, the first part of the line opened using gas-lit wooden carriages hauled by steam locomotives. The Metropolitan Railway operated all services until the District Railway introduced its own trains in 1871. The railway was soon extended westwards through Earl's Court to Fulham, Richmond, Ealing and Hounslow. After completing the inner circle and reaching Whitechapel in 1884, it was extended to Upminster in Essex in 1902.
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.
Electric locomotives were first used on the London Underground when the first deep-level tube line, the City and South London Railway (C&SLR), was opened in 1890. The first underground railways in London, the Metropolitan Railway (MR) and the District Railway (DR), used specially built steam locomotives to haul their trains through shallow tunnels which had many ventilation openings to allow steam and smoke to clear from the tunnels. It was impractical to use steam locomotives in the small unvented tubular tunnels of the deep-level lines, and the only options were rope haulage or electric locomotives.
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 1935 Stock was an experimental train design by Metropolitan Cammell in London. Twelve two-car units, marshalled into four six-car trains, were built. They served as the prototypes for the later 1938 Stock.
The 1920 Tube Stock consisted of forty cars built by Cammell Laird in Nottingham, England. These cars were the first new tube cars to be built with air operated doors. The batch consisted of twenty trailer and twenty control trailer cars, which were formed into six-car trains by the addition of twenty French motor cars built in 1906 and modified for air-door operation. They initially ran on the Piccadilly tube, but in 1930 were considered to be drab, compared to new stock being delivered at the time. The motor cars were therefore replaced by Standard Stock units, built in 1927, and the 1920 cars were refurbished. They were transferred to the Bakerloo line in 1932, and continued to operate until 1938.
The Central London Railway Stock were electric multiple units composed of trailers that had been converted from carriages designed to be hauled by electric locomotives with new motor cars. The Central London Railway opened in 1900 with electric locomotives hauling wooden carriages, but the heavy locomotives caused vibrations that could be felt in the buildings above the route. It was found that conversion to electric multiple units solved the problem, so new motor cars were bought and replaced all the locomotives by June 1903. Trains normally ran with six-cars, four trailers and two motor-cars. Some trailers were equipped with control equipment to allow trains to be formed with three cars.
Ealing Common Depot is a London Underground railway depot on the District line, located between Acton Town and Ealing Common stations in west London, England. It is the oldest of the main depots on the Underground, having been built in 1905, when the District Railway was upgraded for electric traction. All depot facilities were moved there from Lillie Bridge Depot, and it was known as Mill Hill Park Works. It subsequently became Ealing Common Works, and its status was reduced to that of a depot in 1922, when Acton Works was opened, and took over responsibility for all major overhauls. Most of the functions of Acton Works were devolved back to the depots, including Ealing Common, in 1985.
The Acton–Northolt line (ANL), historically known as the New North main line (NNML), is a railway line in West London, England. Built between 1903 and 1906, it runs from the Great Western Main Line at Old Oak Common TMD to the Chiltern Main Line at South Ruislip, alongside the West Ruislip branch of the London Underground Central line, for a distance of around 11 miles (18 km).
District Railway electric multiple units were used on London's Metropolitan District Railway after the lines were electrified in the early 20th century.
The history of the District line started in 1864 when the Metropolitan District Railway was created to create an underground 'inner circle' connecting London's railway termini. The first part of the line opened using Metropolitan Railway gas-lit wooden carriages hauled by steam locomotives. The District introduced its own trains in 1871 and was soon extended westwards through Earl's Court to Fulham, Richmond, Ealing and Hounslow. After completing the 'inner circle' and reaching Whitechapel in 1884, it was extended to Upminster in East London in 1902. To finance electrification at the beginning of the 20th century, American financier Charles Yerkes took it over and made it part of his Underground Electric Railways Company of London (UERL) group. Electric propulsion was introduced in 1905, and by the end of the year electric multiple units operated all of the services.
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.
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