British Rail Class 450

British class of electric multiple unit train

This article concerns the electric multiple unit used by South Western Railway. For the diesel multiple unit used by Northern Ireland Railways see NIR Class 450

British Rail Class 450 Desiro
South Western Railway Class 450 No. 450111 at Basingstoke
In service5 October 2003 – present
ManufacturerSiemens AG
Family nameDesiro
Constructed2002–2006
Entered service2003–2006
Number built127 trainsets
Formation4 cars per trainset
Fleet numbers450001–450042 450071–450127 450543–450570
Capacity450/0 24 first class, 240 standard class per trainset - 450/5 240 standard class per trainset
Operator(s)South Western Railway
Specifications
Car body constructionAluminium
Car length20.4 m (67 ft)
Width2.796 m (9.17 ft)
DoorsPlug sliding 1/4 and 3/4 position
Articulated sectionsInter-unit and inter-vehicle flexible diaphragm
Maximum speed100 mph (160 km/h)
WeightTotal: 170 tonnes
Power supplyThird rail
Electric system(s)750 V DC
Braking system(s)Air, regenerative
450060 and an unidentified 450 between Berrylands and Surbiton. Note the flat roof at the rear of the units capable of being fitted with a pantograph.
450040 at London Waterloo on 21 August 2007, with 444014

The British Rail Class 450 third rail DC Electric multiple unit (EMU) (or 4Des) began service during 2003. They are a part of the Siemens Desiro modular train family and are more popularly known as the 'Blue Desiro'. In standing with requirements of all new rolling stock for the South East region, provision has been made for future conversion to 25 kV AC overhead supply or dual voltage, although at present no trains have been fitted with a pantograph. Used for outer suburban services, the Class 450 is fitted with Standard and First accommodation. The unit has a maximum speed of 100 mph (160 km/h).