British Rail Class 170 Turbostar

The Bombardier Class 170 Turbostar was a family of 139 two- and three-car diesel multiple unit sets built between 1998 and 2005 by Adtranz (later Bombardier Transportation) at Derby, forming the second generation of the Turbostar platform that had been introduced with the Class 168 for Chiltern Railways. Where the Class 168 had been designed to a single operator's specific requirements, the Class 170 was conceived as a modular, flexible product that could be configured to meet the varying needs of multiple franchises across the privatised railway — and it succeeded comprehensively, being ordered by seven different operators and serving across a remarkable geographic spread from the Scottish Highlands to the south of England.

The Turbostar body was a significant advance over the Sprinter family that the Class 170 was progressively replacing. The aluminium body shell was lighter than the steel construction of the Class 158, and the aerodynamically styled, slightly raked nose — the profile that defined the Turbostar look — was both functionally effective at speed and visually distinctive in a way that the flat-fronted Sprinter family had never been. Each power car was fitted with two MTU 6R 183TD13H diesel engines producing 422 hp each, giving the two-car set 844 hp and a maximum speed of 100 mph. The interior was designed to a higher standard than any previous British DMU, with wide aisles, comfortable seating, full air conditioning, power sockets, and a passenger information system.

The Class 170 fleet was ordered and delivered in five subclasses across multiple operators. The 170/1 (170101–170117) went to Midland Mainline for cross-country and East Midlands services; the 170/2 (170201–170208) to South West Trains; the 170/3 (170301–170308) to Hull Trains for open-access King’s Cross–Hull services; the 170/4 (170401–170478) was the largest subclass, delivered to Central Trains and ScotRail for wide-ranging regional services; and the 170/5 (170501–170523) went to First TransPennine Express and subsequently West Midlands Trains. The diversity of routes on which the 170 has operated is remarkable: from Hull Trains’ high-speed King’s Cross workings to ScotRail’s Highland main line services to Aberdeen and Inverness, and Central Trains’ sprawling cross-country network through the Midlands.

Under the various franchise changes and refranchising rounds of the 2000s and 2010s, the Class 170 fleet was redistributed considerably. As of 2026, the class is operated by CrossCountry (on Birmingham-based cross-country services), Greater Anglia (East Anglian regional services), ScotRail (the largest current operator, with a substantial fleet on Edinburgh–Fife, Highland, and Aberdeen services), Transport for Wales, and West Midlands Trains. The Hull Trains examples have been replaced by newer Class 180 and Class 802 sets. Hull Trains’ original 170/3s passed to other operators; none of the class has been withdrawn and scrapped as of 2026, reflecting the high quality and maintained condition of the fleet.