British Rail Class 455
The British Rail Class 455 is a Mark 3-based electric multiple unit passenger train built by BREL between 1982 and 1985. Upon their introduction, they replaced Class 508s as well as aging Southern Railway slam-door stock on commuter services out of London Waterloo.
Whilst the trains were originally built utilising recycled DC traction equipment from Southern Railway 4Sub rolling stock from the 1940s, South West Trains refitted their units with AC traction equipment provided by Vossloh in 2017; despite this change however the trains retained their original gearboxes. The units are operated on suburban services in Greater London and Surrey by South Western Railway, as well as formerly by Southern. They are currently being replaced by the Class 701 EMU on the South Western Railway network.
Description
The Class 455 was originally to be classified as the Class 510, which were planned as a version of the. However, as the chopper control system at the time was not considered robust enough for the electrically rougher third rail Southern Region, they were fitted with GEC Traction camshaft-control systems instead. The Class 510 designation was changed to Class 455.The class has the same bodyshell as the and, but as they were designed for inner suburban services they do not feature first class seating, air conditioning or toilet facilities and are restricted to. Like the Class 317/318, as well as the diesel, they are based on the British Rail Mark 3, with a steel construction, unlike the earlier PEP based,,, and, which have aluminium alloy bodies.
Between 1982 and 1985, a total of 505 carriages were built by British Rail Engineering Limited's Holgate Road carriage works. When combined with 43 existing trailers from s, they formed 137 four-car sets. The Class 455 allowed the and to be withdrawn, as well as allowing the Class 508 units to be transferred to the Merseyside network for which they were originally intended. They also allowed other stock to be cascaded to the North London and Oxted lines.
There were three batches of Class 455 units, all consisting of four cars: driving trailer vehicles at each end, an intermediate trailer vehicle and an intermediate motorised vehicle, all originally built to the standard class 3+2 seating arrangement with 316 seats. Technically, they are formed DTSO+MSO+TSO+DTSO.
Class 455/8
The Class 455/8 units were built between 1982 and 1984. These include all 46 units formerly operated by Southern and 28 allocated to South Western Railway. The last day of service of the Southern Class 455/8 was 14 May 2022.Class 455/7
The Class 455/7 units were built in 1984–1985. There are 43 four-car units, all allocated to South Western Railway at Wimbledon depot. They differ from the Class 455/8 in having a revised front end that was later used on and units.No new intermediate trailer vehicles were produced for this subclass; instead, they use redundant TSO vehicles that had been removed from units prior to those units being transferred to Merseyrail in Liverpool. The reused vehicles can be recognised by their lower and wider profile compared to 'normal' Class 455 vehicles, as well as different windows.
Class 455/9
The Class 455/9 units were built in 1985, and all 20 units are allocated to South Western Railway at Wimbledon depot. These were similar to the 455/7s, except that they had new-build TSOs.In 1990, two units were fitted with chopper traction control to demonstrate the feasibility of operation on the South Western Railway. Car No. 5912 and Nos. 5916–20 were equipped with chopper systems manufactured by GEC Traction and Brush, respectively. During the test runs, the GEC system showed only marginal energy savings, while the Brush system suffered from ongoing reliability problems with its traction control. Eventually, both cars reverted to their original resistance control systems.
In connection with the Crossrail project, which was rejected in 1994, two trailer cars were modified to take plug doors. Both were coupled and ran in service in this condition. After an extended period in service, it was found that the modifications had slightly weakened the overall structure. One train was re-fitted with sliding doors, but the other was removed from service, remaining at Eastleigh Works to be cannibalised for spare parts. The latter car served as a demonstrator for the South West Trains refurbished full red livery until it was scrapped in 2005.
Two units later gained replacement carriages that had originally been part of the prototype DEMU, which had the same bodyshell. 455912's TSO was replaced by 67400. 455913's MSO 62838, which had been crushed by a cement mixer lorry falling off a bridge, was replaced with 67301, which had originally been a Class 210 DTSO and was later a DMSO in the experimental. The undamaged end of 62838 was used to replace the former cab end of 67301; the remainder of 62838 was scrapped.
The last units of the 455/9 fleet were scrapped in late 2025.
Operations
Current operations
South West Trains / South Western Railway
In February 1996, all South Western division 455s were transferred to South West Trains. From September 1996, SWT began to modify the Network SouthEast livery with a Stagecoach orange brand added. In November 2004, SWT took delivery of the first unit refurbished by Bombardier, Ashford. The work involved replacing the original seats with high-back Grammar seats in 2+2 configuration, modifying the doorways so that the sliding doors can open further, and the repainting of the units in a new predominantly red livery. The last was completed in March 2008.In April 2013, it was announced that the SWT units would be fitted with a new alternating current traction system provided by Vossloh Kiepe. The project works commenced in June 2014 and involved replacing the original pneumatically actuated camshaft control system with a solid-state insulated-gate bipolar transistor inverter and variable-voltage/variable-frequency drive, and exchanging the as-built English Electric DC traction motors with new AC units. The upgraded units also received new Knorr-Bremse brake controllers, which allows regenerative braking in addition to the existing rheostatic function.
The new traction motors are each lighter than the DC originals, and the traction system upgrade as a whole improves reliability and reduces overall operating and maintenance costs. Additionally, as the upgrade reduced the amount of time Class 455 units spent being inspected and serviced in depots, South West Trains were able to proceed with the introduction of new units without needing to acquire more depot space.
All units passed to South Western Railway with the South Western franchise change in August 2017. They are used on most London commuter rail routes from to South West London and neighbouring areas.
In the early months of 2024, unit 455868 received a repaint into British Rail Blue and Grey livery. The repaint was made to celebrate the career of the class, and also its reliability, as the fleet has won many Golden Spanner awards during its service with both operators.
A farewell tour for the South Western Railway Class 455 fleet took place on 21 December 2025 operated by the Branch Line Society.
Former operations
British Rail
Deliveries commenced in 1982 to Strawberry Hill. On 16 November 1982, a train was unveiled at, with the first entering service on 28 March 1983. All were initially allocated to Wimbledon Depot working services on the Central and South Western divisions. The Central Division 455/8s were transferred to Selhurst in 1986 after modifications to the depot were completed. All were delivered in British Rail blue and grey livery; it had been anticipated that some or all 455/9s would be painted in a green variant of the 'Jaffa Cake' London & SouthEast livery, but this was overruled by the BR Design Panel. From 1986 all 455s were progressively repainted in Network SouthEast white, blue and red livery. In May 1991, 455743 was renumbered 455750 and renamed Wimbledon Traincare Depot in recognition of the depot obtaining BS5750 quality services accreditation.During April 1994, amid the lead up to the privatisation of British Rail, 46 trains were allocated to the Network SouthCentral shadow franchise and sold to Eversholt. The remainder were allocated to the South West Trains shadow franchise and sold to Porterbrook.
Connex South Central / Southern
On 13 October 1996, the Network SouthCentral shadow franchise was taken over by Connex South Central, using 46 Class 455 trains. In the late 1990s, 16 were repainted in Connex's white and yellow livery. In August 2001, the franchise passed to Southern with all 46 transferred. Some were repainted in Southern's white and green livery. Between February 2004 and February 2006, all were refurbished by Alstom at Eastleigh Works. New 3+2 high back seating as fitted to the and the removal of cab end gangways to facilitate the installation of driver's air-conditioning were notable features.A second refurbishment programme started for the Southern units in June 2012. This included a repaint and interior changes, such as changes to the grab rails on the top between each door. The refurbishment of the first train was completed in August 2012, and the project was completed in December 2013.
A third refurbishment programme began in January 2018 for the 455s to become compliant with the PRM 2020 specifications.
Southern Class 455 units were used on inner and outer suburban services out of London to destinations in South London and Surrey, before being withdrawn in May 2022. They were not directly replaced, as the May 2022 timetable planned all Class 455 services to be operated by existing Class 377s. A farewell tour for the Southern Class 455 units took place on 14 May 2022.
The first pair of Southern Class 455s were sent for scrap on 4 May 2022.