Class 769 Flex

In the mid-2010s there was a need for diesel multiple units to replace life-expired stock such as the Pacer family but (at the time) little chance of new DMUs being built. Instead, Porterbrook in conjunction with Northern, sought to fill the gap with converting surplus Class 319 electric multiple units into bi-mode multiple units with diesel power packs. The result was the Class 769 Flex which retains it's EMU systems (indeed the two diesels feed power into the unit's existing traction system) and so can take it's power from electrified lines where available.
GWR 769 959 on test at Guildford


Information
Number built: 36 (Conversions from Class 319)
Built: 2017-21 (Original build 1987-90)
Builder: Brush Traction (conversions)
Motor: 2 MAN D2876 diesels
Power: 1, 046 hp (780 kW)

Work began at Brush's Loughborough Works in 2017 with Class 769s ordered by Northern, Transport for Wales and Great Western Railway (their examples will be "tri-mode" as they will be able to take their power from overhead and third rail). Testing of the first example began in 2018 however, the development of the trains has not been trouble free and has had numerous delays and reliability problems. Northern hoped to start using their Class 769s in 2019 but this was delayed until 2021. Transport for Wales' units entered service in 2020 though have not been without technical issues. GWR hopes to start using their 769s before the end of 2022.

A parcel carrying version of the unit is the Class 768.
769 959 departs on test