BR/BREL

'BR/BREL' is used in this encyclopedia where a British Railways locomotive or multiple unit class was designed and built jointly by the central BR engineering staff and British Rail Engineering Limited, BR's wholly-owned engineering subsidiary established in 1969 under the Transport Act 1968 to consolidate the former BR Workshops into a single corporate structure. BREL's thirteen main sites at formation gave it the manufacturing capacity to undertake almost all of BR's rolling stock new-build and heavy overhaul work.

The BR/BREL relationship was a close one: BR's central engineering and traction teams specified the performance requirements and key engineering parameters, while BREL's drawing offices and manufacturing teams developed the detailed designs and built the vehicles. This collaborative approach produced the most significant and numerous classes of the 1970s and 1980s, including the Class 56 and Class 58 heavy freight diesel locomotives, the InterCity 125 HST power cars (Class 43), and the extensive Sprinter and Express Sprinter DMU family (Classes 150, 155, 156, 158, 159) that modernised BR's regional and rural passenger services.

BREL also built large numbers of EMUs in this period, including the Class 313, 314, 317, 318, 319, 320, and 321 families for the electrified commuter networks around London, Glasgow, and the North-West. The progressive privatisation of BREL from 1989 ended the integrated BR/BREL design arrangement: the locomotive-building component was sold to ABB Transportation in 1992, eventually passing through ADtranz and Bombardier to Alstom, while the carriage-building at Derby Litchurch Lane and other sites passed through similar ownership changes.