View source for British Rail Class 450

{{Short description|British electric passenger train}}
{{Use dmy dates|date=February 2021}}
{{more citations needed|date=January 2023}}
{{Distinguish|NIR Class 450}}
{{Infobox train
| background = #{{SWR colour}};color:white
| name = British Rail Class 450 ''Desiro''
| image = 20230527 SWR 450054.jpg
| imagealt = 
| imagesize = 300px
| caption = A [[South Western Railway (2017–2025)|South Western Railway]] Class 450 at {{stnlnk|Barnes}} in 2023
| interiorimage = SWR Class 450 Standard Class Interior.jpg
| interiorimagealt = 
| interiorcaption = Refurbished standard-class saloon
| stocktype = 
| service = 5 October 2003{{snd}}present
| manufacturer = [[Siemens Transportation Systems]]
| designer = 
| assembly = 
| ordernumber = 
| factory = {{ubl|[[Vienna]], [[Austria]]<ref name="Factory">{{cite magazine|title=Desiro: Technical Data |magazine=[[Modern Locomotives Illustrated]]|issue=178|date=August 2009|pages=13–15}}</ref>|[[Uerdingen]], [[Germany]]<ref name="Factory"/>}}
| family = ''[[Siemens Desiro|Desiro]]''
| replaced = {{ubl|{{brc|411}}|{{brc|412}}|{{brc|421}}|{{brc|423}}}}
| yearconstruction = 2002–2006<ref name="Siemens Mobility">{{cite book |title=Trains - Reference List |date=8 September 2006 |publisher=Siemens Transportation Systems |location=Erlangen |page=39 |url=https://www.mobility.siemens.com/en/data/pdf/ts_tr/02_reference_brochure_trains.pdf |access-date=30 December 2021 |archive-url=https://web.archive.org/web/20111006082417/http://www.mobility.siemens.com/en/data/pdf/ts_tr/02_reference_brochure_trains.pdf |archive-date=6 October 2011 }}</ref>
| yearservice = 
| refurbishment = 2017–2020<ref>{{cite news |title=SWR completes £70m 'Desiro' refurbishment as final train enters service |url=https://www.firstgroupplc.com/news-and-media/latest-news/2020/10-01-20c.aspx |access-date=13 January 2023 |publisher=FirstGroup plc |date=10 January 2020 |location=Aberdeen}}</ref>
| yearscrapped = 
| numberconstruction = 
| numberbuilt = 127<ref name="AngelTrains">{{cite web |title=Our Fleet - Class 450 |url=https://angeltrains.co.uk/fleet/class-450/ |url-status=live |access-date=2021-12-29 |publisher=Angel Trains |place=London |archive-url=https://web.archive.org/web/20210904235511/https://angeltrains.co.uk/fleet/class-450/ |archive-date=2021-09-04 }}</ref>
| numberservice = 
| numberpreserved = 
| numberscrapped = 
| predecessor = 
| successor = 
| formation = 4 cars per unit:<br />{{abbr|DMOC|Driver's cab, Motor car, Open saloon, Composite (first and standard class sections)}}-{{abbr|TOSL|Trailer car, Open saloon, Standard class, Lavatory}}-{{abbr|TOSLW|Trailer car, Open saloon, Standard class, Lavatory, Wheelchair accommodation}}-DMOC<ref name="ot450">{{cite web |title=Our Trains - Class 450 'Desiro' |url=https://www.southwesternrailway.com/travelling-with-us/our-trains/class-450-desiro |website=South Western Railway |publisher=First MTR South Western Trains |place=London |access-date=13 January 2022 |archive-url=https://web.archive.org/web/20220119140928/https://www.southwesternrailway.com/travelling-with-us/our-trains/class-450-desiro |archive-date=19 January 2022 |url-status=live}}</ref>
| diagram = 
| code = 
| fleetnumbers = 450001–450127
| capacity = {{ubl|As built: 264 seats<br />(24 first-class, 240 standard)<ref name="ti450">{{cite book |title=Technical Information: Class 450 |date=2003 |publisher=Siemens Transportation Systems |location=London |url=http://www.siemenstransportation.co.uk//pdfs/450.pdf |access-date=11 January 2023 |archive-url=https://web.archive.org/web/20071107210506/http://www.siemenstransportation.co.uk//pdfs/450.pdf |archive-date=7 November 2007 |url-status=dead}}</ref>|As refurbished: 285 seats<br />(16 first-class, 269 standard)<ref name="ot450" />}}
| owner = [[Angel Trains]]<ref name= AngelTrains />
| operator = [[South Western Railway]]
| depots = [[Northam Traincare Facility|Northam]]<ref name="Siemens Mobility" />
| lines = 
| carbody = [[Aluminium]]
| trainlength = {{convert|81.60|m|ftin|abbr=on}}<ref name="techinfo">{{cite book |title=Technical Information: Desiro UK Electrical Multiple Unit Family |date=2005 |publisher=Siemens Transportation Systems |location=Erlangen |id=Order No. A19100-V800-B251-V2-7600}}</ref>
| carlength = {{convert|20.34|m|ftin|abbr=on}}<ref name="AngelTrains" />
| width = {{convert|2.796|m|ftin|abbr=on}}<ref name="techinfo" />
| height = 
| lowfloor = 
| floorheight = {{convert|1.157|m|ftin|abbr=on}}<ref name="techinfo" />
| platformheight = 
| entrylevelorstep = 
| wheeldiameter = {{convert|850|–|786|mm|2|abbr=on}} {{avoid wrap|(new–worn)}}<ref name="techinfo" />
| wheelbase = Bogies: {{avoid wrap|{{convert|2.600|m|abbr=on}}}}<ref name="firstbogies">{{cite book |title=First Class Bogies |publisher=Siemens Transportation Systems |location=Graz |pages=60–61, 67 |edition=08/08 |url=http://www.mobility.siemens.com/mobility/global/SiteCollectionDocuments/en/rail-solutions/components-and-systems/bogies-catalog-en.pdf |access-date=11 January 2023 |archive-url=https://web.archive.org/web/20130627060250/http://www.mobility.siemens.com/mobility/global/SiteCollectionDocuments/en/rail-solutions/components-and-systems/bogies-catalog-en.pdf |archive-date=27 June 2013 }}</ref>
| maxspeed = {{convert|100|mph|km/h|abbr=on}}<ref name="Siemens Mobility" />
| weight = {{ubli|indent=1em|{{convert|175.71|t}}<ref name="ti450" />}}
| axleload = 
| steep gradient = 
| traction = Siemens SIBAS [[Insulated-gate bipolar transistor|IGBT]]<ref name="techinfo" />
| traction motors = 8 × Siemens 1TB2016-0GB02<br />[[induction motor|asynchronous]] [[three-phase electric power|three-phase AC]]<ref name= AngelTrains />
| poweroutput = {{convert|1500|kW|abbr=on}} {{avoid wrap|(at wheel)<ref name="techinfo" />}}
| tractiveeffort = Starting: {{cvt|200|kN}}<ref name="ti450" />
| acceleration = approx. {{cvt|1|m/s2|ft/s2}}<ref name="techinfo" />
| deceleration = 
| aux = 
| powersupply = 
| hvac = 
| electricsystem = {{750 V DC|conductor=y}}
| collectionmethod = [[Contact shoe]]
| uicclass = Bo′Bo′+2′2′+2′2′+Bo′Bo′<ref name="techinfo" />
| bogies = Siemens SGP SF5000<ref name="techinfo" />
| minimum curve = {{cvt|120|m|ftin}}<ref name="firstbogies" />
| brakes = [[Electro-pneumatic brake system on British railway trains|Electro-pneumatic]] ([[Disc brake#Rail and aircraft|disc]]) {{avoid wrap|and [[Regenerative brake#Electric railway vehicle operation|regenerative]]}}
| safety = {{ubl|[[Automatic Warning System|AWS]]|[[Train Protection & Warning System|TPWS]]}}
| coupling = [[Dellner]] 12<ref name="sd001">{{cite book |title=System Data for Mechanical and Electrical Coupling of Rail Vehicles in support of GM/RT2190 |date=22 June 2011 |id=SD001 |publisher=Rail Safety and Standards Board |publication-place =London |page=4 |url=http://www.rssb.co.uk/SiteCollectionDocuments/rv_coupling_system_data/SD001.pdf |access-date=22 November 2022 |archive-url=https://web.archive.org/web/20120401203135/http://www.rssb.co.uk/SiteCollectionDocuments/rv_coupling_system_data/SD001.pdf |archive-date=1 April 2012 |url-status=dead}}</ref>
| multipleworking = Within class, {{avoid wrap|and with {{brc|444}}<ref name="ot450" />}}
| gauge = {{Track gauge|sg|allk=on}}
| notes = 
}}

The '''British Rail Class 450 ''[[Siemens Desiro|Desiro]]''''' is a type of [[Third rail|third-rail]] [[Direct current|DC]] [[electric multiple unit]] (EMU) passenger train that entered service during 2003. Used for outer-suburban services, the units were built with both first- and standard-class accommodation. They have a maximum speed of {{convert|100|mph|km/h|abbr=on}}.

The ''Desiro UK'' family also includes units of Classes [[British Rail Class 185|185]], [[British Rail Class 350|350]], [[British Rail Class 360|360]], [[British Rail Class 380|380]] and [[British Rail Class 444|444]].

Along with the Class 444 ''Desiro'', the Class 450 units are operated by [[South Western Railway]].

== Introduction ==
[[File:5 1312 CIG units in Clapham CS with 450077 and the Queen of Scots stock. 250205.jpg|thumb|left|A Class 450 unit between two [[British Rail Class 421|Class 421s]] at Clapham Junction depot in February 2005, less than three months before the latter were withdrawn.]]
In April 2001, 785 vehicles were ordered by [[South West Trains]] in order to complete the replacement of its [[slam door trains|slam-door rolling stock]], in accordance with its franchise commitment to do so by 2005, as the slam-door trains, many of which were more than 40 years old, did not meet modern health and safety requirements. Introduction to service was delayed by the required power supply upgrades capable of powering the new trains, which feature air conditioning, a feature not present in the slam-door trains they replaced. In the December 2004 timetable change, the Class 450 ''Desiro'' began serving most intended routes, although introduction was delayed until June 2005 in some areas.  The units are leased by [[Angel Trains]] to South Western Railway.<ref name= AngelTrains />

Sixty-eight new vehicles were ordered by South West Trains as a replacement to the growth order which was diverted to form the similar {{brc|350}} range of electric multiple units.

== Operations ==
[[File:General Railway Pictures 2011 234.jpg|thumb|[[South West Trains]] Class 450 unit at {{stnlnk|Camberley}} in 2011]]
[[File:SW 450 450558 (8343436351).jpg|thumb|South West Trains Class 450 unit near Clapham Junction in 2012]]
Class 450 units operate suburban, outer-suburban, and regional services from [[London Waterloo railway station|London Waterloo]]. They are used on all SWR lines except the non-electrified [[West of England Main Line]] and [[Eastleigh to Romsey Line]].

On occasion Class 450 units are also used on the [[Portsmouth Direct Line]] for services between Waterloo and [[Portsmouth Harbour railway station|Portsmouth Harbour]], in place of the intended [[British Rail Class 444|Class 444]]. The difference in comfort{{snd}}particularly the higher-density 2+3 seating arrangement used on the Class 450 fleet{{snd}}has prompted complaints from some passengers affected by the substitution.<ref>{{cite news |date=22 January 2007 |title=Commuter protest over rail seats |work=BBC News |publisher=British Broadcasting Corporation |url=https://news.bbc.co.uk/1/hi/england/hampshire/6288115.stm |access-date=29 January 2008}}</ref>

Both the Class 444 and 450 fleets are maintained at the purpose-built [[Northam Traincare Facility]] in [[Southampton]], which is equipped to perform both preventative and corrective maintenance, deep-cleaning, and overhauls on up to eight units simultaneously.<ref>{{cite web |title=Class 450 and Class 444 - South West Trains |url=http://w3.siemens.co.uk/mobility/uk/en/rail_solutions/Commuter_Regional/Service/Class450/Pages/SW.aspx |publisher=Siemens Mobility |access-date=11 January 2023 |archive-url=https://web.archive.org/web/20170628143113/http://w3.siemens.co.uk/mobility/uk/en/rail_solutions/Commuter_Regional/Service/Class450/Pages/SW.aspx |archive-date=28 June 2017 |url-status=dead}}</ref>

In March 2012, the Class 450 fleet, along with the Class 458 and 444 fleets, was fitted with regenerative braking.<ref>{{Cite news|url=https://www.railtechnologymagazine.com/Rail-News/Green-braking-for-South-West-Trains/|title=Green braking for South West Trains|newspaper=Rail Technology Magazine}}</ref>  

=== Class 450/2 and more orders ===
Originally, SWT's order with Siemens was for 100 four-car sets (the current 450/0) and 32 five-car sets, intended as Class 450/2 for inner-suburban use. The [[Strategic Rail Authority]], however, did not agree to the terms required, such as the lengthening of platforms and changes to railway infrastructure. As a result, the 32 five-car sets were cancelled and the 160 vehicles redistributed; an extra 10 four-car sets were added to the SWT order, while the remaining 120 vehicles were then ordered as 30 four-car sets of the dual-voltage {{brc|350}} for [[Silverlink]] and [[Central Trains]].

Subsequently, SWT received further 17 four-car sets, bringing the total number of Class 450 units up to 127.<ref name="Siemens Mobility" /> These trains were delivered in 2006, not long after the last of the first order was delivered.

=== Class 450/5 modifications ===
In January 2008, 28 Class 450/0 sets were modified and re-numbered in the '''Class 450/5''' series, for use on services between [[London Waterloo railway station|Waterloo]] and [[Windsor & Eton Riverside railway station|Windsor]], the [[Hounslow Loop Line]], as well as between Waterloo and [[Weybridge railway station|Weybridge]]. They had their first-class seating removed and replaced with 2+3 formation standard-class seating, and some other seats were removed to provide more standing capacity; extra handrails were also provided. The numbers modified are 450043 to 450070, which have become 450543 to 450570 respectively and displayed the letters HC (denoting 'High Capacity') above the unit number on the front of the sets. The modifications were carried out at the [[Bournemouth Train & Rolling Stock Maintenance Depot|Bournemouth Traincare Depot]].<ref>{{cite web |url= http://www.therailwaycentre.com/News%20January%202008/240108_SWT.html |archive-url= https://web.archive.org/web/20081029064220/http://www.therailwaycentre.com/News%20January%202008/240108_SWT.html |url-status= usurped |archive-date= 29 October 2008 |title= High capacity Class 450 Desiro sets enter traffic |date=24 January 2008 |access-date = 29 January 2008 |publisher= TheRailwayCentre.com}}</ref>

In anticipation of the [[British Rail Class 458|Class 458/5]] modifications for use on the Windsor Lines, the 450/5 sub class had the First Class reinstated, and they are now used generally across the SWR routes. These trains retained their 4505xx number as the standard seating configuration remained different but as they completed their SWR interior refurbishment during late 2019 they were returned to their original numbers.

== Refresh ==
South Western Railway, as part of its franchise award in 2017, has carried out a refurbishment programme on its Class 450 fleet. As part of this, every unit has been deep cleaned with carpets and seat covers replaced and every two seats in standard class have had a plug socket fitted. The 24 first class seats carried in the centre of one of the intermediate trailers<ref name="tr">{{cite book |last1=Marsden |first1=C. J. |url=https://archive.org/details/tractionrecognit0000mars/page/226/mode/2up |title=Traction Recognition |date=2007 |publisher=Ian Allan Publishing |isbn=978-0-7110-3277-4 |location=Hersham |pages=226–227 |oclc=230804946 |ol=16902750M |url-access=registration}}</ref> were replaced with standard-class rows, while new first-class areas of eight seats each were installed immediately adjacent to each driver's cab. These areas feature new leather seats and tables with wireless charging facilities. As part of this work, subclass /5 high-capacity units have also been similarly refurbished, and returned to their original numbers, meaning that all Class 450s once again share a common layout.<ref>{{cite web |url= https://www.southwesternrailway.com/other/about-us/our-plan/transformation-and-growth/train-refurbishment |title=Train Refurbishment |website=South Western Railway |publisher=First MTR South Western Trains |place=London |url-status=dead |archive-url=https://web.archive.org/web/20181130030325/https://www.southwesternrailway.com/other/about-us/our-plan/transformation-and-growth/train-refurbishment |archive-date=30 November 2018}}</ref>

== Accidents and incidents ==
On 6 November 2017, unit 450025 was derailed near {{stn|Wimbledon}}.<ref name=BBC41883153>{{cite news |url= https://www.bbc.co.uk/news/uk-england-london-41883153 |title=South West Railways train derails near Wimbledon |work=BBC News |publisher=British Broadcasting Corporation  |date=6 November 2017 |access-date=6 November 2017}}</ref> Four people were injured; over 300 passengers were evacuated from the train.<ref name=ITN061117>{{cite news |url= http://www.itv.com/news/london/2017-11-06/hundreds-evacuated-and-one-person-injured-after-train-derails-near-to-wimbledon/ |title=Hundreds evacuated and four people injured after train derails near to Wimbledon |publisher=Independent Television News |date=6 November 2017}}</ref> The accident was caused by track spread (an increase in the distance between rails), and occurred on a {{convert|120|m|yd|0|adj=on}} stretch of line that had not been inspected or maintained for many years because of a misunderstanding between [[Network Rail]] and [[London Underground]] as to which company was responsible for its upkeep.<ref name="RAIBWimbledon">{{cite book |title=Safety Digest 01/2018: Derailment of a passenger train near Wimbledon, south-west London, 6 November 2017 |date=February 2018 |publisher=Rail Accident Investigation Branch, Department for Transport |location=Derby |url=https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/679597/D012018_180207_Wimbledon.pdf |access-date=7 February 2018 |archive-url=https://web.archive.org/web/20190725095140/https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/679597/D012018_180207_Wimbledon.pdf |archive-date=25 July 2019 }}</ref>

On 4 March 2024, unit 450092 was derailed between {{rws|Woking}} and {{rws|Surbiton}} stations when it struck an obstruction on the line whilst travelling at a speed of {{cvt|90|mph|km/h}}. No-one was injured and the train was safely evacuated.<ref name=BBC68466494>{{cite news |url=https://www.bbc.co.uk/news/uk-england-surrey-68466494 |title=Woking: Train derailed on 90mph line after hitting object on track |work=BBC News |date=4 March 2024 |accessdate=4 March 2024}}</ref><ref name=NRWokingTweet>{{Cite tweet |user=NetworkRailWssx |author=Network Rail Wessex |number=1764656638391124194 |title=Here's an update on our plan to get the railway back up and running for tomorrow morning. It might not look like a big job, but first we've got to get the train's front wheels back on the rails. Our 'rerailing' team are on site now deciding on the best way to do that /3}}</ref>

== Fleet details ==
{{More citations needed section|date=August 2024}}
{| class="wikitable"
!Class
!Operator
!Qty.
!Year built
!Cars per unit
!Unit nos.
|-
!450
|[[South Western Railway]]
|align=center|127
|align=center|2002–2006
|align=center|4
|450001–450127
|}

===Interiors===
<gallery>
450086 Standard Class Interior.jpg|Original standard-class interior in 2012
450086 First Class Interior.jpg|Original first-class interior in 2013
SWR Class 450 First Class Interior.jpg|Refurbished first-class interior in 2020
</gallery>

=== Illustration ===
{{Wide image|South Western Railway Class 450.png|x50px|Illustration of a South Western Railway Class 450 unit}}

===Named units===
Some units have been named:
*450014 - ''[[King Athelstan]]''<ref>{{Cite web |title=All aboard for Athelstan: SWR names a train after England’s first King |url=https://www.ianvisits.co.uk/articles/all-aboard-for-athelstan-swr-names-a-train-after-englands-first-king-83764/ |access-date=2025-09-04 |website=ianVisits}}</ref>
*450015 - ''Desiro''<ref name="MLI"/>
*450042 - ''Treloar College''<ref name="MLI">{{cite magazine|title=Desiro: Fleet Listing |magazine=[[Modern Locomotives Illustrated]]|issue=178|date=August 2009|pages=72–76}}</ref>
*450056 - ''Hotshot''<ref>{{Cite web |title= |url=https://x.com/SW_Help/status/1990462554997485865}}</ref>
*450067 - ''Key Workers'' - also given a special livery<ref>{{cite magazine|title=Railway Herald :: Imaging Centre :: 450067 at Woking |url=https://www.railwayherald.com/imagingcentre/view/599527/LC |magazine=Railway Herald}}</ref>
*450100 - ''Transport Benevolent Fund CIO''<ref>{{cite magazine |last=Butlin|first=Ashley|title=Multiple Units|department=Stock Update |magazine=[[The Railway Magazine]] |issue=1468 |date=July 2023 | page=87}}</ref>
*450114 - ''Fairbridge Investing in the Future'' (de-named)<ref>{{cite magazine |title=Naming Update |department=Fleet Review |last1=Bendall |first1=S. |last2=Coward |first2=A. |magazine=Railways Illustrated |publisher=Mortons Media Group |place=Horncastle |issue=241 |date=March 2023 |page=23 |issn=1479-2230}}</ref>
*450127 - ''Dave Gunson''<ref>{{cite magazine|last=Clifton|first=Paul|title=Class 450 named in honour of SWT guard|department=Network News |magazine=[[Rail Magazine]] |issue=832 |date=2 August 2017 | page=11}}</ref>

== References ==
{{reflist}}

== External links ==
{{Commons}}
* [https://www.southwesternrailway.com/travelling-with-us/our-trains/class-450-desiro Class 450 "Desiro"] - South Western Railway
* [https://www.youtube.com/watch?v=Dbt5jAFGB64 Class 450 refurbishment]

{{UK Desiro}}
{{British Rail EMU}}

[[Category:British Rail electric multiple units|450]]
[[Category:Siemens multiple units]]
[[Category:Train-related introductions in 2003]]
[[Category:750 V DC multiple units]]