Class 165 Networker Turbo

Class 165 Networker Turbo
Name	Class 165 Networker Turbo
Service	1990–present
Manufacturer	British Rail Engineering Limited
Family	Networker
Yearconstruction	1990–1992
Formation	2/3 cars per unit
Operator	Chiltern Railways; Great Western Railway; First Great Western Link
Carbody	Steel
Maxspeed	75 mph (121 km/h)
Gauge	1,435 mm (4 ft 8+1⁄2 in)

Class 165 Networker Turbo The Class 165 Networker Turbo is a British diesel multiple unit built for commuter and regional services. Introduced in the early 1990s by British Rail Engineering Limited, the type served suburban routes radiating from London Paddington, London Marylebone, and Reading railway station and later operated by multiple post-privatisation companies. The fleet is noted for work on routes linked to Thames Valley, Cotswolds, and Chiltern Main Line services, and has had roles alongside other types such as Class 150 and Class 166.

Design and development

Built by British Rail Engineering Limited at the Holgate Road carriage works site, the units were part of the wider Networker family developed during the InterCity 125 era and the late British Rail modernisation programmes. Design objectives included replacing ageing Class 117 and Class 121 sets on services out of Paddington and Marylebone and improving accessibility for commuters using interchange hubs like Maidenhead railway station and Slough railway station. The procurement process involved consultations with the Office of Passenger Rail Franchising and later interactions with private operators such as Great Western Railway and Chiltern Railways after Railway privatisation in Great Britain. Technical choices—steel carbody, multiple working compatibility, and diesel transmission—were influenced by earlier projects involving British Rail Class 321, British Rail Class 365, and lessons from Network SouthEast operations. Contractors included suppliers tied to Rolls-Royce plc and Brown, Boveri & Cie-related engineering firms.

Technical specifications

Powerplants use diesel engines produced under arrangements that involved firms linked to Perkins Engines and transmission systems with technology comparable to equipment used on Class 158 units. The sets were built in two- and three-car formations to match route capacity demands on corridors serving Oxford, Aylesbury, Reading, Banbury, and High Wycombe. The brake systems and bogies reflect developments from earlier rolling stock programmes including components traced to Metro-Cammell designs. Maximum permitted speed is 75 mph, with acceleration and braking tuned for frequent stops at suburban stations such as Gerrards Cross, Windsor & Eton Central, and Slough. Passenger accommodation mirrors standards applied in the Privatisation of British Rail era and includes features to comply with regulations influenced by bodies like the Rail Safety and Standards Board and accessibility guidance connected to Disability Discrimination Act 1995.

Operations and service history

Initially introduced on Thames Valley and Chiltern routes, the fleet entered service concurrent with changing franchise boundaries involving operators such as Great Western Trains, First Great Western Link, and later FirstGroup. Units were allocated to depots at Reading TMD, Tyseley, and Marylebone depot, running alongside regional trains serving Newbury, Wokingham, Oxford Parkway, and Leamington Spa. During the 2000s and 2010s, the units underwent refurbishment programmes coordinated with franchise agreements affecting Arriva Trains Northern and operational partnerships tied to regional authorities such as Oxfordshire County Council and Buckinghamshire Council. Fleet cascades saw movement to services linking Banbury with Marylebone and temporary duty on relief workings toward Plymouth during rolling stock shortages related to deliveries of new Class 800 and Class 387 fleets.

Liveries and fleet allocations

Liveries have varied from original Network SouthEast-style colours on examples introduced in the early 1990s to corporate schemes applied by Chiltern Railways, Great Western Railway, and franchise successors including First Great Western. Special promotional liveries commemorated partnerships with organisations such as Royal Agricultural University and local councils in the Thames Valley region. Allocations shifted across depots like Reading, Tyseley, Old Oak Common and Marylebone, with repainting and interior refreshes timed to franchise changes involving National Express and FirstGroup.

Accidents and incidents

Units have been involved in a number of operational incidents typical of long-serving commuter fleets, with recorded events investigated by the Rail Accident Investigation Branch and earlier by the Health and Safety Executive and British Transport Police. Notable occurrences included collisions and derailments requiring emergency response from bodies such as Network Rail and coordination with local emergency services in locations like Didcot Parkway and High Wycombe. Each investigation led to recommendations implemented across regional fleets, affecting procedures overseen by Office of Rail and Road and maintenance regimes at depots such as Reading TMD.

Preservation and legacy

While the majority of the fleet remains in passenger service, some vehicles have been earmarked for withdrawal, sale, or transfer to operators and preservation groups associated with heritage sites like Didcot Railway Centre and initiatives supported by organisations such as the Railway Heritage Trust. The class’s legacy lies in its role bridging late-20th-century Networker design principles and early-21st-century franchise operations, influencing subsequent DMU procurements related to programs featuring British Rail Class 170 and CAF-supplied fleets. Its operational history intersects with broader rail policy developments including debates in the Transport Select Committee and investment decisions involving the Department for Transport.

Category:Diesel multiple units of Great Britain