British Rail Class 71

British Rail Class 71

E5001 at Doncaster Works.
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 Bo-Bo
UIC class 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 collection 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
  • One-hour: 2,552 hp (1,900 kW)
  • Continuous: 2,300 hp (1,720 kW)
Tractive effort 43,800 lbf (195,000 N)
Loco brakeforce 68 long tons-force (678 kN)
Career
Operators Southern Region of British Railways
Numbers
  • E5000–E5023;
  • later E5001–E5024;
  • later 71001–71014
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Withdrawn 1976–1977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 third rail) system.

History

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.[1] They were classified type HA under the Southern Region's pre-TOPS scheme.

Power supply

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.

The danger of electrocution of staff at track level was the entire tenet behind the Southern Region/Railway adopting high-level brake pipes and control jumpers that are so distinctive of SR stock (nicknamed "bagpipes"). Low-level brake pipes were still fitted to maintain standards but only used when high-level could not be. The ten redundant class 71 that were modified to become class 74 emerged from Crewe works with bagpipes in 1967/8 and 19 members of class 33 (a purely diesel powered locomotive), which were modified at Eastleigh for push-pull operation Southern Region TC units were so-fitted along with nearly all SR homed members of shunting classes 03 & 08. In contrast, almost all other contemporary locomotive classes (excepting notably classes 07, 09, 73 [all SR locomotives] & class 50) had the multiple control jumpers and brake connectors on or under the buffer beam - a perilous place to be with 750 volts inches away! Despite overhead equipment being confined to just a handful of yards, class 71 was never retro-fitted with high-level connectors.

Operations

They were mixed-traffic locomotives. Their 2300/2552 hp was, for a small Bo-Bo locomotive, useful in both theatres of heavy freight and express passenger work. Acceleration on passenger trains (even when heavily loaded) was quite astonishing - to the extent the climb out of London Victoria was almost unnoticeable. Prestigious services including the "Night Ferry" (London to Paris overnight by train-ferry) and the "Golden Arrow", the latter a Pullman service, were a mainstay of the class for many years.

Reliability of the class as a whole was good. As more areas of the Eastern section were given over to the flexibilities of Multiple Unit (EMU) operation, however, the class found itself ousted almost completely from passenger work. During their later years their passenger duties were only the 'Night Ferry' and the nightly Victoria-Dover/Ramsgate newspaper train. Even this latter was rostered for a Class 33 (diesel locomotive) on Saturday nights due to the probability of engineering works en route.

Their reliance on the electricity supply proved a hindrance – much freight is moved overnight when congestion on the busy commuter corridors is low. This is also the time when engineering possessions of the track take place – the power being switched off to whole districts while this happens. Subsequently, Class 71 was faced with frequent, circuitous detours purely to stay "on the juice" and an electric-only locomotive was limited in scope for inter-regional freights. The flywheel booster allowed the locomotives to make short movements "off the juice" in yards and depots for example, but not for significant distances. The smaller Class 73 electro-diesel locomotives had deputised for them with ease (albeit often in pairs) and they had the ability to work lines when the power was off and to run into yards on other regions where there was no electricity supply of any kind – Class 71 was beginning to look (once again – see Class 74) like a white elephant. When the end came, most were scrapped in fully working order, purely because they had no work.

A single member of the class survives in preservation, E5001 is also in fully working order (although currently minus its 3rd rail collector shoes). As with the remainder of the class, the preserved example never received the standard SR horns, retaining its air whistles right up until being withdrawn.

Rebuilds and renumberings

In the late 1960s, ten examples were withdrawn, eventually being converted between 1967 and 1968 at the British Rail workshops in Crewe into electro-diesel locomotives. They were originally assigned the numbers E7001–E7010 but were numbered E6101–E6110 and classified type HB in the pre-TOPS scheme. Under TOPS the rebuilt ten became Class 74.

Because of the rebuilds there were three renumberings to fill gaps left by engines rebuilt.

The remaining fourteen became Class 71, numbered 71001–71014, under the TOPS scheme.

The end

The class survived relatively un-scathed with no members being scrapped early. Two were awaiting repair at Ashford due to failures and the end finally came on the last day of 1977 when all 14 members were withdrawn en-bloc as a result of motive power rationalisation. Their rostered duties were turned over to Class 73 electro-diesels as part of a new timetable and better use of that class.

Preservation

The one preserved example (erstwhile 71001) was saved by the National Railway Museum in York and has been restored as E5001.

Table of locomotives[1]
Type HA Renumbered Date
renumbered 		TOPS
No. 		Date withdrawn Notes
E5000 E5024 Dec 1962 — Feb 1968 Rebuilt as Class 74 E6104
E5001 — — 71001 Nov 1977 Preserved
E5002 — — 71002 Nov 1977
E5003 — — — Mar 1968 Rebuilt as Class 74 E6107
E5004 — — 71004 Nov 1977
E5005 — — — Apr 1968 Rebuilt as Class 74 E6108
E5006 — — — Dec 1967 Rebuilt as Class 74 E6103
E5007 — — 71007 Nov 1977
E5008 — — 71008 Nov 1977
E5009 — — 71009 Nov 1977
E5010 — — 71010 Nov 1977
E5011 — — 71011 Nov 1977
E5012 — — 71012 Nov 1977
E5013 — — 71013 Nov 1977
E5014 — — 71014 Nov 1977
E5015 — — — Feb 1968 Rebuilt as Class 74 E6101
E5016 — — — Nov 1967 Rebuilt as Class 74 E6102
E5017 — — — Apr 1968 Rebuilt as Class 74 E6109
E5018 E5003 Dec 1968 71003 Nov 1977
E5019 — — — Feb 1968 Rebuilt as Class 74 E6105
E5020 E5005 Sep 1968 71005 Nov 1977
E5021 — — — May 1968 Rebuilt as Class 74 E6110
E5022 E5006 Sep 1968 71006 Nov 1977
E5023 — — — Mar 1968 Rebuilt as Class 74 E6106

Models

Class 71 is currently available as a kit and a ready-to-run model in OO gauge by Silver Fox Models.[2] Hornby is making three versions of the class 71, which should be available in 2016 (with working pantograph).[3]

References

Further reading

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