British Rail Class 71
E5001 at Doncaster Works.
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| Type and origin | |
|---|---|
| Power type | Electric |
| Builder | British Railways’ Doncaster Works |
| Order number | Doncaster EO3 (3), EO4 (10), EO15 (11) |
| Build date | 1958–1960 |
| Total produced | 24 |
| Specifications | |
|---|---|
| Configuration: |
|
| • Whyte | Bo-Bo |
| • UIC | Bo′Bo′ |
| Gauge | 4 ft 8 1⁄2 in (1,435 mm) |
| Wheel diameter | 4 ft 0 in (1,219 mm) |
| Loco weight | 77.00 long tons (78.24 t; 86.24 short tons) |
| Electric system(s) | 660–750 V DC Third rail (mainline) 650V DC Catenary (sidings) |
| Current source |
Contact shoe (mainline) Pantograph (sidings) |
| Traction motors | English Electric 532 or 532A, 4 off |
| Train heating | Electric Train Heating |
| Loco brake | Dual Vacuum and Air |
| Performance figures | |
|---|---|
| Maximum speed | 90 mph (145 km/h) |
| Power output |
|
| Tractive effort | 43,800 lbf (195,000 N) |
| Brakeforce | 68 long tons-force (678 kN) |
| Career | |
|---|---|
| Operators | Southern Region of British Railways |
| Numbers |
|
| Axle load class | Route availability 6 |
| Withdrawn | 1976–1977 |
| Disposition | 10 rebuilt to class 74, 13 scrapped, 1 preserved |
The British Rail Class 71 was an electric locomotive used on the Southern Region of British Railways. Unlike most other Southern Region electric locomotives (such as classes 73 and 74) they could not operate away from the electrified (750 V DC) system.
As part of the British Transport Commission's Modernisation Plan of 1955, twenty-four electric locomotives were built in 1958 for the Kent Coast main lines. They were built at the British Rail workshops in Doncaster. Numbers were originally E5000–E5023 but the first locomotive, E5000, was renumbered E5024 in December 1962. They were classified type HA under the Southern Region's pre-TOPS scheme.
Power collection was from a 3rd rail at 650 volts DC (Eastern & Central sections) or 750 volts DC (Western section) and control was by flywheel booster, as in British Rail Class 70. In some yards (notably Hither Green, South East London and Snowdown colliery near Dover) overhead catenary energized to 650 V DC was used. This overhead collection method was only employed where it was deemed too dangerous to have third rail with staff constantly at ground level reaching into low running areas to couple and uncouple trains. The overhead system utilised tram-style catenary and pantographs – it was not necessary to collect traction current at speed and these provided a cost saving. The pantograph retracted into a cut-out recess in the roof when not in use, to keep within the loading gauge. Certain examples were delivered new without pantographs and ran with the recess vacant for some time. Evidently supply of the overhead equipment was short. Later in life (when the catenary in yards had almost completely been removed) during overhaul the opportunity was taken, on some examples of the class, to remove the sometimes troublesome pantograph, leading again to a vacant roof recess.
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