The reference for locomotives and railcars
British Rail Southern Region DEMUs
later 6S, 6L, 6B, 3H, 3D, 2H, later BR classes 201 to 207
Great Britain | 1957 | 87 produced
Class 201 No. 1006 in April 1986 at Hastings
Class 201 No. 1006 in April 1986 at Hastings

While most regional divisions of the British Railways procured diesel-mechanic multiple units from 1957, the Southern Region built diesel-electric multiple units. The English Electric 4SRKT with turbocharger and 600 hp was used as the engine. The nickname “Thumper” came about because of the exhaust sound of the big four-cylinder. Two- and three-car units had a total of one engine and six-car units had two engines. For faster passenger exchange, some cars had doors in each compartment. The 201 to 204 and 206 classes were retired between the late 1980s and early 1990s and the 205 and 207 classes remained in service until 2004.

Variant6S (201)3H (205)3D (207)
ManufacturerEastleigh, AshfordEastleigh
Axle configB-2+2-2+2-2+2-2+2-2+2-B B-2+2-2 B-2+2-2+2-2 
Gauge4 ft 8 1/2 in (Standard gauge)
Dimensions and Weights
Length347 ft 10 in128 ft 0 1/4 in191 ft 5 5/8 in
Empty weight510,700 lbs194,000 lbs262,060 lbs
Power sourcediesel-electric
Top speed75 mph
EngineEnglish Electric 4SRKT Mk.II
Engine type2x 4-cyl. diesel4-cyl. diesel
Engine output1,200 hp (895 kW)600 hp (447 kW)
Power Plant
Calculated Values
last changed: 07/2023

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