British Rail Class 378
| Industry | Rail transport manufacturing |
|---|---|
| Headquarters | Derby , United Kingdom |
| Products | Electric multiple units (including Class 378 Capitalstar) |
The British Rail Class 378 Capitalstar is an electric multiple unit passenger train developed specifically for the London Overground system and forms part of the Electrostar series produced by Bombardier Transportation. A total of 57 five-car sets were constructed, with most initially delivered as three- or four-car configurations.
Commissioned in August 2006 as replacements for aging fleets such as the Class 313 units operated by Silverlink, the Class 378 was intended to enhance operational performance rather than refurbish older trains. Built at Bombardier’s Derby manufacturing plant, the first train entered revenue service in July 2009, approximately six months later than planned due to supplier-related delays.
The Class 378 incorporates design features similar to the Class 376 units used by Southeastern, including broader metro-style sliding pocket doors that facilitate rapid passenger flow. Distinctively, it employs fully longitudinal seating akin to that found on London Underground rolling stock, optimizing standing room and alleviating congestion to better serve high-density metro routes on the London Overground.
History
By the early 2000s, numerous obsolete rolling stock types remained active across London, notably within the Silverlink franchise on the North London line, which was often criticized for overcrowding and unreliable services. The then-operational Class 313 trains featured outdated interiors and were perceived as uninviting, particularly during nighttime operations. Driven by a desire to enhance service standards, Transport for London (TfL) pursued a modern replacement for these units.
In August 2006, TfL entered into a £223 million agreement with Bombardier for an initial order of 152 cars, scheduled for delivery starting September 2008, with an option to increase to 216 cars. This contract also covered maintenance services and the establishment of a new depot near New Cross Gate railway station. The resulting fleet, designated as Class 378, was assembled at Bombardier’s Derby facility.
In July 2007, TfL placed an additional order for 36 Capitalstar carriages valued at £36 million to enhance capacity on the East London Line and extend North London Line trains from three to four cars, with deliveries expected in 2011. The first fully assembled Class 378 unit was revealed in September 2008 and underwent testing prior to entering passenger service. TfL also acquired three dual-voltage units to support operations on the South London line.
By February 2013, TfL approved a further acquisition of 57 vehicles aimed at lengthening all Class 378 sets from four to five cars, thereby increasing capacity network-wide. Five-car formations commenced service on the East London Line in November 2014 and were expanded across the entire network by late 2015. By January 2016, every unit operated in this extended five-car format.
Initially purchased outright by TfL, ownership of the fleet was transferred under a leaseback arrangement to QW Rail Leasing in 2007; similarly, the additional fifth cars were leased in 2013. Both lease agreements extend until June 2027. In March 2023, TfL requested authorization to end these leases prematurely and repurchase the fleet, citing potential cost reductions and lowered financial risk. This acquisition strategy aims to maintain operation of the Class 378 trains until their anticipated service life concludes in 2044. The repurchase was finalized during summer 2023 for £281 million.
Design and features
The Class 378 Capitalstar is a dual-voltage electric multiple-unit (EMU) engineered to operate on both 750 V DC third rail systems and overhead line electrification. This model represents a tailored variant of Bombardier's Electrostar series, specifically designed for short-distance urban transit. Following the completion of five-car expansions in 2016, each trainset comprises a driving motor car and an intermediate motor car positioned on either side of a central trailer car. In the Class 378/2 subclass, the trailer is outfitted with the pantograph and electrical transformer.
The interior layout prioritizes passenger volume by substituting conventional seating with longitudinal benches and incorporating broad doorways to facilitate rapid boarding and disembarking. A significant section of each carriage is allocated for standing passengers, equipped with grabrails akin to those found on London Underground trains. Given the relatively brief duration of journeys on the North London Line, onboard toilets are omitted. Contemporary features include air conditioning, real-time passenger information system displays, wheelchair access with level boarding, and distinct seat moquette patterns to indicate priority seating areas.
To ensure safety within the confined single-bore tunnels of the East London Line, each driver's cab is fitted with a detrainment device, which consists of foldable stairs that deploy from the cab’s nose door.
Sophisticated sensors track passenger numbers per carriage to optimize energy consumption for heating and related systems. External CCTV footage is automatically relayed to an in-cab monitor when doors open, removing the necessity for additional platform-based driver-only operation (DOO) apparatus. In emergency situations, internal CCTV feeds appear on the driver’s screen, allowing direct communication through an intercom system with passengers involved.
Operations
Originally planned for service commencement in January 2009, the Class 378 faced a seven-month delay due to the 2008 economic downturn, which led to supplier insolvencies and shortages of components. This disruption similarly affected deliveries of comparable Class 377/5 units intended for First Capital Connect. As a result, the first Class 378 entered operational service on 29 July 2009.
In 2011, several Class 378 units experienced unexpected shutdowns on the North London Line caused by harmonic interference from passing Class 92 freight locomotives. Bombardier addressed this problem by recalibrating interference tolerance parameters.
By January 2016, Transport for London (TfL) had completed extending all 57 units to five-car formations. However, in December 2018, unit 378232 was reverted to a four-car setup to operate on the Gospel Oak to Barking line due to delays in delivery of Class 710 trains. Additionally, units 378206 and 378209 were temporarily shortened to four cars to cover services following the withdrawal of diesel-powered Class 172 trains.
In July 2015, London Overground placed an order for 45 new Class 710 units, some of which replaced Class 378 trains on the Watford DC line. The displaced Class 378s were redeployed to strengthen other routes. By late 2018, London Overground updated the Class 378 fleet’s livery and seat moquette to align visually with the newer Class 710 trains.
In January 2018, all Class 378 trains were briefly taken out of service for urgent safety inspections after one unit suffered a brake caliper failure.
Fleet
The Class 378 fleet is divided into two variants: the DC-only 378/1 and the dual-voltage 378/2, which can operate on both AC and DC power supplies:
- Class 378/1 – These twenty four-car trains run exclusively on 750 V DC and serve the extended East London Line. They replaced the A60/A62 Stock and were introduced on 27 April 2010, initially running between Dalston Junction and New Cross/New Cross Gate. By May 2010, services extended to Crystal Palace and West Croydon. As members of the Electrostar family, these units have a recessed roof design allowing space for pantographs, anticipating future dual-voltage capability. Southern services on the South London line ceased in 2012, succeeded by air-conditioned Class 378 trains operated by London Overground.
- Class 378/2 – Comprising thirty-seven four-car units, these dual-voltage trains operate across the North London, West London, Watford DC, East London, and South London lines. They are powered by both 25 kV AC overhead lines and 750 V DC third rail systems. Introduced from 2010 onwards, they replaced the older Class 313 and Class 508 fleets. The initial batch of 24 units began as three-car Class 378/0 sets (378001–378024) but were later lengthened to four cars and reclassified as Class 378/2 (renumbered to 378201–378224). The remaining thirteen units (378225–378234 and 378255–378257) were constructed as four-car dual-voltage trains from inception.
| Class | Operator | Quantity | Year built | Cars per unit | Unit numbers | Lines served | Additional information |
|---|---|---|---|---|---|---|---|
| 378/1 | London Overground | 20 | 2009–2010 | 4 | 378135–378154 | Powered solely by third rail. | |
| 378/2 | 24 | 2008–2010 | 378201–378224 | Dual-voltage capability; initially three-car Class 378/0. | |||
| 13 | 2010–2011 | 378225–378234, Template:Avoid wrap | Built as four-car dual-voltage units. |
Named units
Several units have been given special names:
- 378135: Daks Hamilton
- 378136: Transport for London
- 378204: Professor Sir Peter Hall
- 378205: Every Story Matters #LondonForEveryone (displays unique livery celebrating the LGBTQ+ community)
- 378211: Gary Hunter
- 378232: Jeff Langston
- 378233: Ian Brown CBE