British Rail Class 40

English Electric Type 4
British Rail Class 40
40145 at Carlisle on 27 August 2004, whilst working a charter train. This locomotive is the last remaining 'centre headcode' type Class 40.
Type and origin
Power typeDiesel-electric
BuilderEnglish Electric at Vulcan Foundry and Robert Stephenson and Hawthorns
Build date1958–1962
Total produced200
Specifications
Configuration:
 • Whyte1Co-Co1
 • UIC(1Co)'(Co1)'
Gauge4 ft 8 12 in (1,435 mm) standard gauge
Wheel diameterDriving: 3 ft 9 in (1.143 m)
Idling: 3 ft 0 in (0.914 m)
Minimum curve4.5 chains (91 m)
Wheelbase61 ft 3 in (18.67 m)
Length69 ft 6 in (21.18 m)
Width9 ft 0 in (2.74 m)
Height12 ft 10 in (3.91 m)
Loco weight133 long tons (135 t)
Fuel capacity710 imp gal (3,200 L; 850 US gal)
Prime moverEnglish Electric 16SVT MkII
TransmissionDC generator, DC traction motors
MU working Blue Star
Train heatingSteam generator
Train brakesVacuum
Performance figures
Top speed90 mph (140 km/h)
Power outputEngine: 2,000 bhp (1,490 kW)
At rail: 1,550 hp (1,160 kW)
Tractive effortMaximum: 52,000 lbf (231 kN)
Brakeforce51 long tons-force (508 kN)
Career
Railroad(s)British Railways
NumberD200–D399, later 40001–40199
Axle load classRoute availability 6

The British Rail Class 40 is a type of British railway diesel locomotive. Built by English Electric between 1958 and 1962, and eventually numbering 200, they were for a time the pride of the British Rail early diesel fleet. Despite their initial success, by the time the last examples were entering service they were already being replaced on some top-link duties by more powerful locomotives. As they were slowly relegated from express passenger uses, the type found work on secondary passenger and freight services where they worked for many years, the final locomotives being retired from regular service in 1985.