The Alstom Aventra (sold as the Bombardier Aventra until 2021) is a family of

electric multiple unit An electric multiple unit or EMU is a multiple-unit train consisting of self-propelled carriages using electricity as the motive power. An EMU requires no separate locomotive, as electric traction motors are incorporated within one or a number o ...

(EMU) passenger trains produced at

Derby Litchurch Lane Works Derby Litchurch Lane Works, formerly Derby Carriage and Wagon Works, is a railway rolling stock factory in Derby, England. It is presently owned by the multinational transportation manufacturer Alstom. Derby works originally commenced productio ...

in the United Kingdom, originally by

Bombardier Transportation Bombardier Transportation was a Canadian rolling stock and rail transport manufacturer, with headquarters in Toronto and Berlin. It was one of the world's largest companies in the rail vehicle and equipment manufacturing and servicing industry. ...

and later by

Alstom Alstom SA () is a French multinational rolling stock manufacturer which operates worldwide in rail transport markets. It is active in the fields of passenger transportation, signaling, and locomotives, producing high-speed, suburban, regional ...

, as a successor to the

Bombardier Electrostar The Bombardier Electrostar (sold as the ADtranz Electrostar until 2001) is a family of electric multiple unit, electric multiple-unit (EMU) passenger trains manufactured by Bombardier Transportation (formerly Adtranz) at their Derby Litchurch L ...

. A large proportion of its design is based on the Electrostar, adding new technologies and achieving compliance with more stringent requirements and operator demands. Bombardier began developing the Aventra in 2009 based on feedback from

train operating companies In the railway system of Great Britain, a train operating company (TOC) is a railway undertaking operating passenger trains under the collective National Rail brand. TOCs have existed since the privatisation of the network under the Railways ...

(TOCs) and upcoming regulation changes. It has been designed to provide a generic platform for conducting inter-regional, commuter, metro, and high-speed passenger services. It has been claimed to be more efficient and flexible than the Electrostar, which was mainly achieved via the greater use of digital technology. The development of a

bi-mode An electro-diesel locomotive (also referred to as a dual-mode or bi-mode locomotive) is a type of locomotive that can be powered either from an electricity supply (like an electric locomotive) or by using the onboard diesel engine (like a Diese ...

version of the Aventra, incorporating batteries, was proposed as a replacement for existing diesel multiple-units. The first order for the Aventra came from the

Crossrail Crossrail is a completed railway project centred on London. It provides a high-frequency hybrid commuter rail and rapid transit system, akin to the Réseau Express Régional, RER in Paris and the S-Bahn systems of German-speaking countries, kn ...

programme in 2014. Numerous other operators have since ordered the type, including

London Overground London Overground (also known simply as the Overground) is a Urban rail in the United Kingdom, suburban rail network serving London and its environs. Established in 2007 to take over Silverlink Metro routes, it now serves a large part of Greate ...

Greater Anglia Greater Anglia (legal name Transport UK East Anglia Limited) is a British train operating company owned as a joint venture by Transport UK Group and Mitsui & Co. It operates the East Anglia franchise, providing the commuter and inter-city se ...

South Western Railway South Western Railway Limited, trading as South Western Railway (SWR), is the British state-owned train operating company that took over the services of the South Western Railway (2017–2025), operator of the same name from FirstGroup and MTR ...

c2c Trenitalia c2c, trading as c2c, is a British train operating company that operates commuter services from its London terminus at to parts of East London and south Essex along the London, Tilbury and Southend line, as part of the Essex Thame ...

and

West Midlands Trains West Midlands Trains (WMT) is a British train operating company. It operates passenger trains on the West Midlands franchise between London and the English Midlands under two trading names: within the West Midlands region as West Midlands Rai ...

Description

The Aventra was developed by Bombardier Transportation principally as a successor to their prolific Electrostar

(EMU) family, the final example of which was delivered during 2018 after nearly twenty years of continuous production. According to Niall Simmons, Bombardier's Head of Bids Engineering, development work on what would become the Aventra had begun as early as 2009, although its design had significantly evolved during this time in response to the feedback gathered from various

. The platform was to be made adaptable to serve various subsections of the passenger rail market, including inter-regional, commuter, metro, and high-speed services. Furthermore, the introduction of increasingly stringent regulations had driven a need either to extensively redesign the Electrostar, or to develop a replacement family. Bombardier has reportedly invested in excess of £50million into the development of the Aventra. In comparison with the Electrostar, the Aventra has been designed to be lighter and more energy-efficient, with greater flexibility. It has also been claimed to provide greater levels of comfort and reliability. Among the differences in the design are various measures to improve operational efficiency, including the adoption of wider gangways and doors to shorten station dwell times by speeding up passenger boarding; the gangway has reportedly been designed to allow better use of the interior space and ease of movement throughout the train. The Aventra features a redesigned interior, which Bombardier has indicated to be the main visual difference between the two platforms. A major area of divergence between the two platforms is the greater use of digital technology on board the Aventra platform, partly in response to operators' requests, such as the train control management system. The platform also uses

predictive maintenance Predictive maintenance techniques are designed to help determine the condition of in-service equipment in order to estimate when maintenance should be performed. This approach claims more cost savings over routine or time-based preventive maint ...

instead of traditional prescriptive maintenance. Far more reporting information spanning more functionality is generated by the Aventra than on the previous Electrostar family. The signalling apparatus supports the

European Rail Traffic Management System The European Rail Traffic Management System (ERTMS) is the system of standards for management and interoperation of signalling for railways by the European Union (EU). It is conducted by the European Union Agency for Railways (ERA) and is the o ...

(ERTMS). Structurally, the Aventra is relatively lightweight, the body of each carriage having been redeveloped from the Electrostar. It comprises various welded assemblies that attached to one another via bolts. The vehicle also incorporate the FlexxEco bogie, previously used in service on other Bombardier trainsets, such as the Voyager and some of the later-built Turbostars. While the older Electrostar family are not compliant with the Technical Standards of Interoperability (TSI) introduced in 2017, the Aventra was specifically designed for compliance with the more rigorous regulatory requirements. During 2018, Bombardier promoted the prospective development of a

version of the Aventra, intended to be capable of speeds up to . This bi-mode trainset, which would have incorporate batteries, positioned itself as a potential successor to several older diesel multiple-units, such as the Bombardier Turbostar and Voyager platforms. The primary manufacturing site for the Aventra was established at Bombardier's

facility; Simmons has stated that the Derby production line was intended to manufacture the type not only to fulfil British orders but also those placed by overseas operators. Each operator can choose to customise the design of its Aventra fleet; common variations have included different vehicle lengths, modified propulsion systems, and interior changes. Much of the onboard equipment has been designed to be flexible and upgradable. Some customers, such as the

, have intentionally stylised their Aventra's interiors to maintain a high degree of commonality with their existing Electrostar fleets. In November 2021,

signed a memorandum of understanding with

Eversholt Rail Group Eversholt Rail Group is a British rolling stock company (ROSCO). Together with Angel Trains and Porterbrook, it is one of the three original ROSCOs created as a result of the privatisation of British Rail. Eversholt was established in March 19 ...

to build 10 three-car hydrogen multiple units. These trains never got ordered.

Orders

As of May 2024 a total of 2,651 vehicles have been built for six operators:

Crossrail

The first order for the Aventra platform was a £1billion contract for 65 Class 345 nine-car EMUs (with an option for 17 more) for the London

programme in February 2014, which built the

Elizabeth line The Elizabeth line is a railway line that runs across Greater London and nearby towns, operating similarly to the Réseau Express Régional, RER in Paris and the S-Bahn systems of German-speaking countries. It runs services on dedicated infras ...

. These are operated by Elizabeth line concession holder MTR Crossrail and have replaced Class 315, Class 360 and Class 387 on Shenfield Metro,

Heathrow Heathrow Airport , also colloquially known as London Heathrow Airport and named ''London Airport'' until 1966, is the primary and largest international airport serving London, the capital and most populous city of England and the United Kingdo ...

and

Reading Reading is the process of taking in the sense or meaning of symbols, often specifically those of a written language, by means of Visual perception, sight or Somatosensory system, touch. For educators and researchers, reading is a multifacete ...

services respectively. In July 2017, it was announced that the order would be increased to 70 trains; the contract for the additional trains was signed in March 2018. In April 2024, with the future viability of the Derby Litchurch Lane manufacturing plant in serious doubt due to a lack of orders, a further follow-on order for 10 additional trains was indicated (5 previously agreed plus a further 5 trainsets making a total of 10 trains) in response to strong growth of passenger numbers on the Elizabeth Line and future expected service increases to cope with the interchange with High Speed 2 services at Old Oak Common Interchange. In June 2024 it was announced that the aforementioned 10 more 9 car Class 345s had been ordered.

London Overground

ordered 54 four-car trains ( Class 710) in July 2015, with an option remaining for 15 more, similar to those being used for Crossrail. They have replaced Class 315, Class 317, Class 172 and Class 378 or the entire fleet in 2019 on

Lea Valley The Lea Valley (also spelt Lee Valley), the valley of the River Lea, has been used as a transport corridor, a source of sand and gravel, an industrial area, a water supply for London, and a recreational area. The London 2012 Summer Olympics wer ...

Gospel Oak Gospel Oak is an area of north west London in the London Borough of Camden at the very south of Hampstead Heath. The neighbourhood is positioned between Hampstead to the north-west, Dartmouth Park to the north-east, Kentish Town to the south-ea ...

and Watford DC lines and are operated by London Overground concession holder

Arriva Rail London Arriva Rail London is a train operating company owned by Arriva UK Trains that operates the London Overground concession on behalf of Transport for London. History In April 2015, Transport for London placed a notice in the '' Official Journa ...

Greater Anglia

In August 2016

was awarded the new East Anglia franchise, including an order with Bombardier for Class 720 units. 22 ten-car trains and 89 five-car trains were originally ordered (665 carriages). They replaced the Class 317, Class 321, Class 360 and Class 379s. Greater Anglia later amended the order with all to be built as five-car sets.

South Western Railway

On 20 June 2017, Bombardier was awarded a contract to build 750 cars for

(SWR). The Class 701 units are into 30 five-car and 60 ten-car sets and replace SWR's

455 __NOTOC__ Year 455 ( CDLV) was a common year starting on Saturday of the Julian calendar. At the time, it was known as the Year of the Consulship of Valentinianus and Anthemius (or, less frequently, year 1208 ''Ab urbe condita''). The denomin ...

suburban fleet. On 9 January 2024, the first Class 701 unit entered revenue service after more than four years of delays.

West Midlands Trains

On 17 October 2017, Bombardier was selected to build a total of 84 Class 730 EMUs (324 carriages) for

. These will be formed into two separate types; 48 three-car units, and 36 five-car units. The 3 car Class 730 sets entered service on 13 November 2023.

c2c

In December 2017,

ordered six ten-car Aventra units, which were proposed to enter service in summer 2021. These will replace six 4-car units leased from 2016. In 2020 the order was amended to be for 12 five-car units instead, mirroring the change made by Greater Anglia to their order. These entered service in September 2023.

Alstom Aventra variants

References

{{British Rail EMU Bombardier Transportation multiple units Alstom multiple units Train-related introductions in 2017