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British Rail Class 142

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British Rail Class 142
NameBritish Rail Class 142
Service1985–2019
Manufacturermero!! (see text)
FamilyPacer
Constructed1985–1987
Numberbuilt96
Formation2-car sets
Fleetnumbers142001–142096
Capacity102–121 seats
OperatorBritish Rail, Regional Railways, Northern Trains, Arriva Rail North, First North Western, TransPennine Express, Arriva Trains Wales, ScotRail
Carlength15.4 m per coach
Width2.82 m
Height3.77 m
Maxspeed75 mph (121 km/h)
Transmissionmechanical
EngineCummins L10
GaugeStandard gauge
BrakesVacuum and later air
CouplingBuckeye
Gauge1,435 mm

British Rail Class 142. The British Rail Class 142 is a class of diesel multiple unit (DMU) built for British Rail between 1985 and 1987 as part of the Pacer family intended to replace first-generation DMUs following the Beeching cuts aftermath and the introduction of the InterCity 125 era. Designed for cost-effective regional and branchline services, the units operated widely across England, Wales, and parts of Scotland until phased withdrawal in the late 2010s amid changing accessibility and emissions regulations.

Introduction

The Class 142 was produced during the Margaret Thatcher government era of railway rationalisation by a consortium including British Leyland's Leyland Bus division and BREL subcontractors, responding to the Serpell Report climate and the needs of Regional Railways. Ordered to provide a low-cost modernisation following the First Great Western and Network SouthEast restructurings, the units entered service with fleet numbers 142001–142096 and became a ubiquitous sight on services once served by Class 101 and Class 108 DMUs.

Design and Development

Built on a bus-derived underframe to reduce costs, the Class 142 used modified Alexander bus bodies mounted on a long-wheelbase chassis influenced by the Leyland National and components from British Rail Engineering Limited. The Pacer concept evolved from prototype experiments such as the Leyland Experimental Unit and reflected lessons from the Modernisation Plan (1963). The design team prioritized low capital expenditure, lightweight construction, and simplified maintenance, drawing on suppliers including Cummins for powerplants and Voith-style transmissions adapted for mechanical drive. Early deployment followed tests overseen by Railtrack predecessors and trial running on the Tyne Valley Line and Ribble Valley line corridors.

Technical Specifications

Each two-car set comprised two driving motor coaches with a formation derived from Leyland National bus architecture, seating arranged longitudinally or with mixed seating depending on operator specification for routes such as StalybridgeHuddersfield and Manchester suburban services. Powered by two inline six-cylinder Cummins L10 diesel engines per set driving via a mechanical gearbox, the units achieved a top speed of 75 mph and rode on modified Brown, Boveri & Cie-type bogie adaptions. Braking systems originally used vacuum brakes later retrofitted with air brakes to comply with Rail Vehicle Accessibility Regulations and to integrate with multiple-working standards used by Class 150 and Class 155 DMUs on shared diagrams.

Operational History

Introduced into service by Regional Railways in the mid-1980s, Class 142s operated intensively on commuter and branch services across the North West England, Yorkshire and the Humber, and Wales networks. Operators over the years included First North Western, Arriva Trains Wales, ScotRail, Northern Rail, and later Arriva Rail North and Northern Trains. Routes served encompassed the Wrexham–Chester line, the Blackpool–Preston corridor, and suburban lines into Leeds and Bradford. The units were noted for cheap construction, high reliability in mileage terms, and mixed passenger reception, especially on long-distance diagrams compared with units such as the Sprinter family.

Accidents and Incidents

Class 142 units were involved in several notable incidents including derailments and collisions investigated by the Rail Accident Investigation Branch and its predecessors. Incidents prompted safety advisories circulated to operators including Network Rail stakeholders. Specific occurrences on routes such as the Dewsbury area and incidents near Chester drew attention to suspension and chassis response under adverse track geometry similar to issues earlier highlighted in the Harrington Humps and platform interface debates. Investigations often referenced standards promulgated after the Clapham Junction rail crash reforms and influenced subsequent fleet recertification and retrofit programmes.

Refurbishment and Modifications

Throughout their working life, many Class 142s received comprehensive refurbishments funded by operators and rolling stock companies, incorporating new seating, HVAC upgrades, installation of automatic passenger counting and CCTV systems, and accessibility modifications including accessible toilets and passenger information systems to meet the Disability Discrimination Act 1995 and later Equality Act 2010 requirements. Mechanical updates included engine replacements, noise-damping measures, and conversion from vacuum to electro-pneumatic braking to allow multiple working with modern DMUs. Some vehicles were trialled with hybrid diesel-electric systems in experimental programmes involving industry partners and local enterprise networks.

Withdrawal and Preservation

Regulatory changes including the Persons with Reduced Mobility Technical Specification for Interoperability and the introduction of Rail Vehicle Accessibility Regulations (2010) accelerated withdrawal of the Class 142 from mainline service, with final operational handovers occurring by 2019. Several units were acquired for preservation by heritage railways such as the Great Central Railway (GCR), the Keighley and Worth Valley Railway, and the East Lancashire Railway, while others found secondary careers as community spaces or on industrial sidings. Preservation efforts involve restoration volunteers from organisations including The Railway Heritage Trust, local councils, and charitable trusts coordinating certification with the Office of Rail and Road.

Category:Diesel multiple units of the United Kingdom