London Underground D78 Stock
A refurbished D78 Stock train at West Ham in 2014
The interior of a refurbished D78 Stock car
In service28 January 1980 – 21 April 2017 (London Underground)
1 November 2021 – present on Island Line (as Class 484)
Built atWashwood Heath, England
ReplacedO and P Stock
R Stock
Number built75 sets (450 cars)
SuccessorS7 Stock
Formation3 cars per unit, 2 units per train
Capacity821 per train
Line(s) servedDistrict
Car lengthDM 18.37 m (60 ft 3 in)
UNDM/T 18.12 m (59 ft 5 in)
Width2.85 m (9 ft 4 in)
Height3.62 m (11 ft 11 in)
Maximum speed72 km/h (45 mph)
WeightDM 27.46 tonnes (27.03 long tons; 30.27 short tons)
UNDM 26.11 tonnes (25.70 long tons; 28.78 short tons)
T 18.40 tonnes (18.11 long tons; 20.28 short tons)
Traction systemPneumatic single camshaft
(GEC Traction)
Traction motorsLT118 DC motor
(Brush Traction)
Seating280 per train
Stock typeSubsurface

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 The first units were withdrawn in January 2015 with the last withdrawn on 21 April 2017.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 D stock was ordered in 1976 to replace the pre-war CO/CP Stock and post-war R Stock on the District line.[1] Seventy-five six-car trains were built by Metro-Cammell, Washwood Heath, the first entering service on 28 January 1980[2] with last delivered in 1983.[3]


D78 stock interior as built, photograph taken during press run, 9 January 1980. Moquette was orange/brown rectangle pattern. Windows were non-opening; hopper ventilators were fitted after complaints of poor ventilation. The trains were the last ones with "bobble springs" hanging from the roof.
Single leaf doorway of D78 stock; photograph taken on press run.
D78 stock in pre-refurbishment condition

The D Stock consisted of six-car trains, as opposed to the seven-car trains of CO/CP and R Stock, whose cars were shorter: under normal operation, each train consisted of two 3-car units, and 20 of the units are double-ended to allow 3-car operations under exceptional circumstances.[4]

The traction motors were the same LT118 type as on 1973 Tube Stock, and the bogies are same, unlike other subsurface rolling stock. With single-leaf doors and transverse and longitude seating, the style is very similar to 1983 stock on the Jubilee line. The D stock and 1983 stock trains were the only trains on the underground to have their headlights positioned under the train body; many trains on the underground had only their tail lights under the body.

The trains brought many innovations. The Metalastik rubber/metal "Chevron" primary springs and 'diabolo'-shaped rubber/metal secondary springs suspension meant a smoother ride for passengers. The driver's cab is more ergonomic, the seat swiveling to move forwards, backwards, up or down. The dead man's handle is replaced by a joystick that needs to be twisted for the dead man feature, and moved fore and aft for motoring and braking. There is a Train Management System replacing the original Train Equipment Panel that highlights faults to the driver.

The most noticeable difference between the stock and earlier trains is that the doors are single leaf. Originally, passengers pressed door-control buttons to open them. Posters explaining how to operate the doors were put up around Tube stations in English, French and German when the stock was introduced. The stock had a "POGO" switch (Passenger open/Guard's open) that could switch control of the doors from passengers to the guard (when the stock was introduced, the guard controlled the doors from the rear cab).

While this function proved useful at above-ground stations and termini (especially in winter), station dwell time was significantly increased, and passengers had trouble getting used to the new system, not knowing how to open the door. By the late 1990s, the control of the doors went to the driver. The buttons remained, but they were covered up on refurbishment between 2004 and 2008.

At over 18 metres (59 ft), the cars were the longest on the Underground. The windows had to be modified because of overheating when new, with pull-down opening windows installed in each car.


D stock Rail Adhesion train at Rickmansworth.

The stock was used on the District line, except the High Street Kensington to Edgware Road section, because the platforms are not long enough for D Stock.[citation needed]

Between April 1985 and May 1987, the stock operated the East London line service in three-car formations, there being enough stock spare because of reduced services on the District line. This allowed A60/62 Stock to be sent for One Person Operation (OPO) conversion. The A60/62 stock took over the service again in 1987. The class received the Class 499/0 designation on British Rail's TOPS system to operate on the Richmond and Wimbledon branches.[5]

The stock started being replaced by S Stock in 2016.[6] It was replaced about 15 years short of its intended lifespan, as a consistent new fleet will allow for frequencies to be increased and will reduce maintenance costs.

In July 2011, Harrogate Chamber of Commerce proposed to use the stock on the Harrogate line from York to Leeds via Harrogate to increase capacity.[7] Stations in the Harrogate and Leeds urban areas are close together: the superior acceleration of the stock over the Class 150 diesel multiple units currently used, is intended to cut journey times. It was proposed that the line would be electrified with third rail, similar to the Docklands Light Railway, as opposed to the London Underground or the Southern Region network.

On 24 July 2012, car 7007 was designated as the Olympic 2012 Train with London Underground Chief Operating Officer Howard Collins carrying the Olympic Torch from Wimbledon to Wimbledon Park.[8] This is the only London Underground train to be an Olympic Torch train.

In March 2017 the first D stock RAT (Rail Adhesion Train) was designated to replace the A60/A62 Stock trains which were currently working as Rail Adhesion Trains. The A stock units were 50+ years old at that point and were ageing rapidly. There are 2 sets made up of units 7010 and 7123 and 7040 and 7107. [9]


Upminster (D) →
Facilities Wheelchair bays Wheelchair bays Wheelchair bays Wheelchair bays Wheelchair bays Wheelchair bays
Numbers 7000






  • 17035 and 17077 exchanged numbers in 1994.
← (A)
(D) →
Facilities Wheelchair space Wheelchair space Wheelchair space
Numbers 7500




De-icing equipment was fitted to trailers 17000 to 17048 (evens).


Interior before refurbishment
Interior of the prototype refurbished car
Interior after refurbishment
The exterior of a newly refurbished train at Ealing Common Depot

The mid-life refurbishment was the first to be carried out under the public–private partnership (PPP), by Metronet, and was delayed until contract negotiations were completed. A prototype unit of three cars (7008/17008/8008) was prepared by London Underground's Train Modification Unit at Acton Depot in 2001.[10][11] This had some detail differences from the eventual refurbishment, and was later brought up to the standard of the rest of the stock. The refurbishment programme began in summer 2005 with the work undertaken by Bombardier Transportation's Derby Litchurch Lane Works.[12][13] The programme was completed in 2008.[14]

The refurbishment consisted of:

The refurbished D Stock were the first Underground trains to have electronic dot-matrix information displays on the sides of the cars; some pre-war trains had slot-in or reversible destination or non-stopping plates. It was also the first type in the subsurface fleet to sound buzzers even when the door opens. The rest of the refurbished sub surface stock only had buzzers when the doors closed.

The refurbished D Stock also had the London Underground roundel painted on the sides of all the cars; previously, only the DM cars had the roundel on them.

Around 2014, the emergency cords were fitted with flap coverings as a safety measure so that passengers only pull the cords in case of emergency.


The D78 Stock and its replacement, the S7 Stock, at Ealing Broadway on the final day of D78 Stock operation.
D78 Stock at Ealing Common Depot on 7 May 2017.

Withdrawals commenced on 19 January 2015 when the first full 6-car train, formed of units 7510 and 7058, was withdrawn from service at Ealing Common Depot and loaded onto trucks for Long Marston for the driving motors to be converted into 230s and the other cars to be either scrapped or stored for future use. The last train, formed of units 7007 and 7032, ran on 21 April 2017.[15]

A farewell heritage tour took place on 7 May 2017 operated by units 7007+7032.[citation needed]

In February 2016, four redundant D78 cars were used by the emergency services in a mock tube accident staged at Littlebrook Power Station.[16]

One car 7012 is preserved by the London Transport Museum Depot at Acton.[citation needed]

Car 7027 is preserved at Coopers Lane School, Lewisham for use as a library.[17]


Main articles: British Rail Class 230 and British Rail Class 484

Class 484 carriage 231 ready to enter service

In 2014 Vivarail purchased 156 driving motor cars and 70 trailer vehicles for conversion to Diesel–electric multiple units.[18] 75 two or three-car units proposed.[19][20] Under TOPS they are designated as Class 230.[21]

A prototype was produced for testing and accreditation in August 2015, with introduction to service in 2016.[22] The first Class 230 service to carry passengers operated on 19 July 2017 when a unit was used to operate a shuttle service from Honeybourne to the Rail Live exhibition at the Quinton Rail Technology Centre.[23]

The first customer for production Class 230 units was West Midlands Trains, which ordered three two-car DMUs in October 2017. Subsequently Transport for Wales Rail ordered a total of five three-car sets, to be built as bi-mode multiple units (BMMUs), in June 2018.[24][25]

ex-D78 Stock Class 484 484001 at Ryde Traincare Depot alongside ex-1938 Tube Stock Class 483 483009.

In September 2019 South Western Railway announced that it would be leasing five two-car Class 484s for use on the upgraded Island Line on the Isle of Wight from 2020. These continue to be powered by electricity drawn from the third rail.[26] The first units arrived on the Isle of Wight on 19 November 2020, and entered service on 1 November 2021 once upgrade works on the island line were completed. While the 484s are considerably taller than the 483s they replaced, a survey of the line prior to the commencement of upgrade works confirmed that the new units would be able to traverse Ryde Tunnel, a requirement for any stock to run on the Island Line. [27]


  1. ^ "District line replacement cars authorised" Railway Gazette International August 1976 page 285
  2. ^ "London Underground Railway Society" (PDF). Underground News. Vol. 219. March 1980. p. 88. ISSN 0306-8617. OCLC 499388777.
  3. ^ "Rolling Stock Data Sheet, London Underground (First Edition)" (PDF). WhatDoTheyKnow. Retrieved 17 April 2016.
  4. ^ Connor 2015, p. 142
  5. ^ "LUL stock given TOPS numbers". The Railway Magazine. No. 1145. September 1996. p. 57.
  6. ^ "Transforming the Tube" (PDF). Transport for London. July 2008. Archived from the original (PDF) on 5 June 2011. Retrieved 28 May 2009.
  7. ^ "HARROGATE LINE NEWS 1 1st Meeting supports bid" (PDF). Harrogate Chamber of Commerce. 12 August 2011. Archived from the original (PDF) on 1 October 2011. Retrieved 26 August 2011.
  8. ^ "Olympic torch: Flame rides on London Underground train". BBC News Online. 24 July 2012. Retrieved 24 August 2012.
  9. ^
  10. ^ "Spellar inspects District Line stock" Rail issue 436 29 May 2002 page 16
  11. ^ D78 modernised Railway Gazette International 1 October 2002
  12. ^ "Metronet tests refreshed D stock" Rail issue 515 8 June 2005 page 26
  13. ^ D78 stock gets a fresh new look Railway Gazette International 1 August 2005
  14. ^ "D78 stock refurbishment complete" Today's Railways UK issue 78 June 2008 page 19
  15. ^ Farewell to the D stock The Railway Magazine 3 May 2017
  16. ^ "Emergency Services Stage Mock Tube Disaster" Rail Express issue 239 April 2016 page 9
  17. ^ Mansfield, Ian (10 November 2016). "Old tube train carriage turned into school library". Retrieved 15 March 2022.
  18. ^ "Viva Vivarail's D-train transformation" Rail issue 771 1 April 2015 page 60
  19. ^ D78 Stock Conversion is Go Archived 16 July 2015 at the Wayback Machine Modern Railways December 2014 pages 37-38
  20. ^ "Vivarail Homepage". Vivarail. Retrieved 20 January 2015.
  21. ^ Sam McCaffrey (1 May 2015). "'They don't make trains like this anymore'". Rail Technology Magazine. Retrieved 17 May 2015.
  22. ^ Old tube trains gain a new lease of life - The Engineer. Retrieved 2020-12-02.
  23. ^ "D-Train to carry passengers" Rail issue 824 13 April 2017
  24. ^ "Vivarail to supply three D-Trains to West Midlands Trains". Retrieved 5 June 2018.
  25. ^ "KeolisAmey reveal new-look Wales trains and services". 4 June 2018. Retrieved 8 June 2018.
  26. ^ Isle of Wight line’s future secured with £26m investment Railway Gazette International 16 September 2019
  27. ^ "Vivarail to supply new train fleet for the Island Line". Rail Insider. 17 September 2019. Archived from the original on 5 June 2020. Retrieved 5 June 2020.