History
The D78 Stock was a type of rolling stock used on the London Underground, introduced between 1980 and 1983 for the District line. Manufactured by Metro-Cammell in Birmingham, it replaced the ageing CO/CP and R Stock trains.
Characterised by wider doors and a more spacious interior, the D78 Stock was designed with passenger comfort in mind and marked a departure from earlier designs. It was also the first stock on the Underground to feature single-leaf doors instead of double-leaf ones, which allowed for smoother and more reliable operation.
The trains served the District line reliably for over three decades. In the early 2010s, Transport for London began replacing them with the new S Stock, part of a broader modernisation programme. The last D78 train was withdrawn from passenger service in April 2017.
Rather than being scrapped entirely, many D78 vehicles found a second life. Some were converted into Class 230 trains by Vivarail for use on National Rail services, extending the legacy of the D78 Stock beyond London.
