Bombardier Electrostar

Family of British electric passenger trains

The Bombardier Electrostar (sold as the ADtranz Electrostar until 2001) is a family of electric multiple unit (EMU) passenger trains manufactured by Bombardier Transportation (formerly Adtranz) at their Derby Litchurch Lane Works in England between 1999 and 2017. It has become the most common new EMU type in the United Kingdom since the privatisation of British Rail with a number of variants. Electrostar trains are most common on high volume suburban commuter routes around London; and on mainline services from London south to Surrey and the south coast, east to Essex, and north to Cambridge and Stansted Airport. The model shares the same bodyshell and core structure as the Bombardier Turbostar which is the most common post privatisation diesel multiple unit (DMU) family; both evolved from the Class 168 Clubman design by ADtranz. The Turbostar and Electrostar platforms are a modular design, sharing the same basic bodyshell and core structure, and optimised for speedy manufacture and easy maintenance. A common underframe, created by seam welding a number of aluminium alloy extrusions, is covered by body panels and topped by a single piece roof, again made from extruded sections. Car ends (cabs) are made from glass reinforced plastic and steel, and are bolted onto the main car bodies. Underframe components are collected in "rafts" which are bolted into slots on the underframe. The predominantly aluminium alloy body gives light weight to help acceleration and energy efficiency. The Electrostar was selected for use on the Gautrain system in South Africa, a new railway between Johannesburg, Pretoria, and the Johannesburg International Airport. The trains were assembled by UCW Partnership in South Africa from components made in Derby. Transport for London (TfL) announced in August 2006 that it had ordered 48 three and four car Electrostar trains for the new London Overground service. These were categorised by Network Rail as Class 378, and entered service in 2009 to replace the Class 313 and Class 508 trains on the North London Line and West London Line, and to provide the opening service on the new East London line extension in 2010. In 2009, as part of the government's wider rolling stock plan, an order was placed for thirty four car Class 379 Electrostar units intended for use by National Express East Anglia (now operated by Greater Anglia) on the Stansted Express and West Anglia services. The first of these units entered passenger service on Thursday 3 March 2011. Production of the trains ended in 2017 when unit number 387174 for Great Western Railway was completed at Derby Litchurch Lane Works. The family was superseded by the Bombardier Aventra.

Class Image Operator(s) Introduced Number Power Carriages Door configuration End gangways Notes 357 Electrostar c2c 1999 74 AC electric 4 "Plug" style No 375 Electrostar Southeastern 1999 112 Dual Voltage/DC electric 3 or 4 "Plug" style Yes Class 375 and 377 differ only in their coupler configuration and other minor fittings; all Southern units built as Class 375 have since been converted to Class 377 couplers and re classed. Minor differences in interior trim remain. 376 Electrostar rowspan="2" rowspan="2" |Southeastern 2004 36 DC electric 5 Sliding pocket No 377 Electrostar 2002 239 Dual Voltage/DC electric 3, 4 or 5 "Plug" style Yes Class 377/6 and Class 377/7s have been built with different exteriors, matching the Class 379s and Class 387s. 378 Capitalstar rowspan="2" rowspan="2" |London Overground 2008 57 Dual Voltage/DC electric 5 Sliding pocket Emergency only The Class 378s were constructed in three separate batches 24 three car units designated as Class 378/0 with dual voltage capability were built for use on the North London Line and West London Line. 20 four car DC only units designated Class 378/1 were built for the East London Line. 13 four car Class 378/2s were also built, and the Class 378/0s had an extra car added to make them Class 378/2s. All later extended to 5 cars. Gautrain Electrostar rowspan="2" rowspan="2" |Gautrain 2010 24 AC electric 4 "Plug" style No 379 Electrostar rowspan="2" rowspan="2" |Stored 2010 30 AC electric4 "Plug" style Yes The Class 379s incorporate some technical features of the proposed Aventra Mark II Electrostar. However they are outwardly similar to Class 375 and Class 377.387 Electrostar 2014 107 Dual Voltage4 "Plug" styleYes Class 387s for Thameslink were ordered to cope with extra service before enough s were built. These transferred to Great Northern, once enough Class 700s were in service. 387/2s have replaced s on Gatwick Express. Great Western Railway units on the Thames Valley services to replace the 165s and 166s. From 2022 Great Northern will operate 6 Class 387/3s these will allow for some the Class 387/2s to be sent to Southern.

c2c uses Class 357 on services down the London, Tilbury and Southend line from Shoeburyness and Southend to London Fenchurch Street.

Southern's Class 377 fleet is found on all parts of the network apart from the non electrified routes. They frequent metro routes, formerly alongside the Class 455s, until the latter's withdrawal in 2022, and Class 456s until they transferred to South West Trains in 2014.

On 8 June 2010, the route between Sandton and OR Tambo International Airport in South Africa opened in time for the 2010 FIFA World Cup. The rest between Johannesburg Park Station and Rosebank was to be completed in 2011. This section was actually opened 7 June 2012, the delay caused by work to resolve a water seepage problem in the single track tunnel section between Rosebank and Park. Although railways in South Africa use the 1067 Cape gauge, Gautrain is built to the more expensive standard gauge of sg. According to the Gautrain planning and implementation study, this is done for several reasons, including that standard gauge is safer and more comfortable to passengers. The rolling stock is also easier, quicker and less expensive to obtain than Cape Gauge rolling stock, and standard gauge is also less expensive to maintain as it is more tolerant of track imperfections than Cape Gauge. Standard gauge allows for travel at Gautrain's required speed of .

From September 2016 Great Western Railway introduced 45 4 car Class 387/1s on peak services between London Paddington and Hayes & Harlington. They currently replace the Class 165s and the Class 166s on the Thames Valley services and now operate between London Paddington and Reading, Didcot Parkway and Newbury. GWR announced in 2018 that they will modify 12 units to be used on Heathrow Express due to the Class 332s no longer having a depot. In December 2019, some services to Reading transferred to TfL Rail as part of the Elizabeth line.

From late 2016, 29 of the Class 387/1s operating on Thameslink were displaced by the delivery of Class 700 Desiro City units, and were transferred to Great Northern. They operate mostly on the Kings Cross Cambridge King's Lynn route, though they can also been seen on other services. These units were delivered in the livery of Southern, with green doors and Southern upholstery.