Лондондық метроның 1938 жылғы вагондарының дизайны

London Underground tube stock design

The London Underground 1938 Stock was a London Underground tube stock design. A total of 1,121 cars were built by Metro Cammell and Birmingham RC&W. An additional 173 cars were added to the fleet by the end of 1953, comprising 91 new builds (the 1949 Tube Stock), 76 conversions from Pre 1938 Tube Stock or 1935 Tube Stock, and six unconverted cars of 1935 Tube Stock, and the stock was used on the London Underground until 1988. During their long lives they worked on the Bakerloo, Northern, Piccadilly, East London, Central, and Northern City lines. Ten sets were refurbished and ran on the Isle of Wight as Class 483, making them the oldest passenger rolling stock operating timetabled services on the National Rail network at the time of their withdrawal in January 2021. The trains represented a major technical advance, as all the electrical equipment was located under the floor for the first time. All previous tube stock had large equipment compartments behind the driving cabs in motor cars, which reduced the space available for passengers by about a third.

As part of the New Works Programme of 1935–1940, there were plans to operate nine car trains of 1938 stock on the Northern line. These cars were originally numbered differently from the other cars, the first digit '1' being replaced by a '9'. The formation for a nine car train would have been DM + NDM + SNDM + T + NDM + T + SNDM + NDM + DM. With the scaling back of the planned extensions for the Northern and Bakerloo lines, and the need to order further stock to balance the fleet (the 1949 stock), cars were renumbered in the early 1950s. The DMs, trailers, as well as twenty eight of the thirty NDMs had the '9' replaced by a '1', the DMs becoming 10324 10333, 11324 11333, the trailers 012389 012408, and the NDMs 12029 12054, 12056 12057. NDMs 92055 and 92058 were rebuilt into Uncoupling Non Driving Motors (UNDMs) along with all twenty SNDMs. The twenty two cars rebuilt into UNDMs were renumbered 30000 30021.

So successful was the 1938 Stock that, when, in 1948, additional cars were needed, 91 almost identical cars were built, 70 non driving motor (NDM) cars and 21 trailer cars. These were known as 1949 stock and operated with the 1938 stock. They were numbered in the same scheme; the UNDMs were numbered 30022 30045, 31000 31045 and the trailers 012495 012515. After World War II, the former 1935 stock streamlined DMs were rebuilt into trailers, and included with the 1938 stock, being renumbered 012477 012494. Before the war, three trailers were built for use with the streamlined DMs. These three cars differed from the 1938 trailers in that they were not equipped with compressors. However, the cars were not delivered until after the war and with the DMs rebuilt the three cars became part of the 1938 stock fleet, being numbered 012412 012414, and fitted with compressors.

Each motor car is fitted with two series DC motors, one on each of the two bogies and are designed to operate from the 630 volt traction supply. Each motor has an output of approximately 250 horsepower. The controllers and switchgear are operated from a 50 volt auxiliary supply provided by a motor generator set. This system allows the master controller at one end of the train to simultaneously operate the switchgear on all the motor cars in a similar manner to the system developed by Sprague for the Elevated railway in Chicago, Illinois some 46 years earlier. This same supply is also used to power the train lighting as well as some other auxiliary circuits.

The motor cars are divided into two distinct types, the 'A' end car and the 'D' end car. Each of the bogies fitted to the two cars is identical. This means that if the two motor cars at the two ends of a train were identical, they would attempt to pull the train in opposite directions. Consequently, the bogies on the 'D' end motor car are installed the other way around from those on the 'A' end causing the two motor cars to move the train in the same direction. The 'A' and 'D' designation is from the designation of the axles on the two bogies. The 'A' end car has the 'A' axle at the driving cab end of the car with the 'B' axle on the opposite end of the same bogie. The 'C' axle on the second bogie is nearest the driving cab with the 'D' axle closest to the coupled trailer car. The sequence is reversed on the 'D' end motor car. This is also why the alternate car is not designated the logically more obvious 'B' end. Another mechanical difference between the two types of car is that the 'D' end car has a spring loaded buffer at the driving cab end whereas the 'A' end car has a solid buffer. These differences mean that when coupling two train sets together, the 'A' end of one set must be coupled to the 'D' end of the other. Although train sets are not normally split in day to day usage, they do have to be split when undergoing major maintenance tasks, such as when the bodies are lifted off of the bogies. This is not a problem on most lines, where all the train sets start and remain the same way around. However, on the Northern line the existence of the Kennington loop, just south of Kennington station, which allows Charing Cross branch trains to depart from its southbound platform and arrive at its northbound platform reverses the complete train once every journey. This means that, on this line, on average, half the trains will be facing in the opposite direction to the remainder. Only sets facing the same way can be coupled together.

The 1938 design stock features the (by this time) standard series/parallel traction control using bridge transition. The control system has an unusual feature. Ordinarily, the driver moves the master controller from 'off' up to 'full series' and then further to the 'full parallel' position when the train will be under full power. The unusual feature is that once the driver has moved the controller to 'full parallel' and the train has accelerated to the point where the switchgear is actually in full parallel, the driver can then move the master controller back to 'full series'. The traction switchgear will remain in 'full parallel' unless the driver moves the master controller from 'full series' to any position towards 'off'. Many drivers took advantage of this feature because it was more comfortable maintaining the downward pressure on the deadman's handle with the handle at the 6 o'clock position (the 'full series' position) rather than the 9 o'clock position (the 'full parallel' position).

In 1938, fifty eight 'Standard Stock' trailers, originally built in 1927, were converted to operate with the 1938 Stock. These cars were renumbered 70513–70570. The first car withdrawn was 70550, as a result of damage sustained in an accident at Watford Junction in 1962, and the last car, 70534, was withdrawn in 1973.

A crash involving 1938 stock occurred at Moorgate on 28 February 1975. A train hit the dead end wall of the station, killing 43 people including the driver in unclear circumstances. After the accident, a safety system named after the crash (Moorgate Protection) was introduced in 1978.

The Chronicles of Narnia: Prince Caspian (2008). The fantasy film features 1938 tube stock at the beginning and end of the film.

On 9 January 2013, 1938 tube stock appeared on a £1.28 British postage stamp as part of a set commemorating the 150th anniversary of the first London underground train journey. The stamp's captions read "Classic rolling stock" and "1938", with the caption's background in Bakerloo line colour.