Class 90

Class 90
Powertype	Electric

Class 90

The Class 90 is a British electric locomotive type introduced in the late 20th century for mixed-traffic duties on the West Coast Main Line, East Coast Main Line, and regional routes. Designed amid network electrification programmes involving the British Rail board, the Department of Transport, and private contractors such as British Rail Engineering Limited and Brush Traction, the type balanced freight capability with passenger service performance. It entered service during a period of organisational change that included the InterCity sector restructuring, the Privatisation of British Rail process, and the emergence of multiple train operating companies like Virgin Trains and Freightliner.

Design and Development

Development began as part of a response to increasing demand for modern electric traction on upgraded intercity corridors, coordinated by the Railtrack infrastructure owner and influenced by European developments exemplified by Siemens and Alstom. The design drew upon lessons from predecessors linked to the British Rail Class 87 and British Rail Class 89 programmes, while integrating technology from suppliers associated with ABB Group, Brush Traction, and GEC Traction. Specifications targeted a Bo-Bo wheel arrangement to suit the track standards maintained by the Rail Safety and Standards Board and to comply with rules overseen by the Office of Rail and Road. Weight distribution and crashworthiness reflected regulations influenced by the Health and Safety Executive and standards cited in documents from the European Commission rail interoperability initiatives.

Prototyping and testing took place on test circuits connected to depots such as Crewe and Doncaster, with acceptance trials involving representatives from British Rail's Research Division and the Railway Industry Association. Final production incorporated cab ergonomics informed by consultations with the Train Drivers' Association (UK) and unions like the RMT.

Technical Specifications

The locomotive features a 25 kV AC overhead electrification collector using a pantograph compliant with Network Rail interface requirements. Traction equipment utilises three-phase AC inverters incorporating power electronics developed in collaboration with firms akin to GEC and Siemens, driving asynchronous traction motors closely related in concept to those fitted to the Eurostar and TGV derivatives. Braking systems combine rheostatic/regenerative capability with air brakes standardised under specifications aligned with the Rail Safety and Standards Board.

Primary dimensions, axle loadings, maximum tractive effort and top speed were tailored for mixed-traffic duties to match operational patterns set by operators including British Rail InterCity, Rail Express Systems, and regional franchises such as ScotRail and Northern Rail. Onboard systems include multiple-unit working compatibility derived from protocols used on formations with Class 47 and Class 86 locomotives and integration with standard-cab signalling aids consistent with procedures at Euston and King's Cross terminals.

Operational History

Entry into service coincided with timetable changes implemented by British Rail and later impacted by market shifts during the Privatisation of British Rail. Units were allocated to principal depots including Crewe South, Doncaster Plant, and Polmadie and operated trains for major operators such as Virgin Trains, Stagecoach Group, and freight operators like DB Cargo UK and Freightliner Group. The locomotives hauled express services on corridors linking London with Glasgow, Manchester, and Birmingham, and performed heavy freight workings for clients using freight terminals at Firms such as Drax power station and ports like Felixstowe.

Throughout service life, the type underwent periodic overhauls at workshops including Brush's Loughborough facility and Wabtec's Doncaster Works, with modifications implemented to meet changing safety directives from Office of Rail and Road and to incorporate innovations similar to those used by Hitachi and Bombardier Transportation on newer fleets. Availability records and performance statistics were reported to industry bodies including the Rail Safety and Standards Board and used by franchise bidders in procurement dossiers.

Variants and Subclasses

Several subclasses and refurbishment packages were produced by contractors comparable to Brush Traction, Wabtec, and private overhaul firms, resulting in changes to gearing, traction control software, and onboard ancillary systems. Some units were fitted with gauge-clearance modifications to operate on routes constrained by structures managed by Network Rail and tunnel portals such as those on the West Coast Main Line upgrades. Other conversions focused on freight optimisation for operators like Freightliner and GB Railfreight, including alterations to train heating and auxiliary power systems to simplify compatibility with rolling stock from builders like British Rail Engineering Limited and Metro-Cammell.

Accidents and Incidents

A number of incidents involved wind-related disruptions on open sections of the West Coast Main Line and collisions at level crossings recorded by the Rail Accident Investigation Branch (RAIB)]. Investigations referenced operational procedures from the Office of Rail and Road and recommendations echoed by the Rail Safety and Standards Board. Major events prompted technical audits at depots such as Crewe and resulted in retrofits to cab safety equipment and enhancements similar to measures later applied to fleets from Bombardier and Siemens.

Preservation and Legacy

Following secondary-market sales and withdrawals, several examples entered preservation on heritage railways overseen by trusts akin to the National Railway Museum and volunteer groups operating depots at locations like Barrow Hill and Didcot Railway Centre. The class' influence can be traced in later designs promoted by manufacturers such as Siemens and Alstom, and it is cited in studies by academic institutions including Imperial College London and University of Birmingham addressing traction lifecycle management. Its mixed-traffic concept informed procurement decisions by franchises including Avanti West Coast and TransPennine Express, and its technological lineage appears in modern traction strategies advocated by the Department for Transport (United Kingdom) and Network Rail.

Category:British electric locomotives