Class 70 'Booster' SR Profile and Models
20002 at Eastleigh Works in 1942. ©Ben Brooksbank
The British Rail Class 70 was a class of three 3rd rail Co-Co electric locomotives. The initial two were built by the Southern Railway1940–41 and 1945. The third was built by British Railways in 1948. Externally, it was clear that the cab design owed a lot to Southern's experience with the 2HAL multiple unit design. It has even been suggested that this was because the jigs for the welded cabs already existed and thus made for speedy and cheap construction. The class soon proved their worth; the six traction motors providing 1,470 hp allowed them to handle 1,000-long-ton freight and 750-long-ton passenger trains with ease.To overcome the issue of becoming marooned between power supplies the locos were fitted with a motor-generator set (or Booster) with a large flywheel. Even while stationary, Class 70 produced a noticeable droning noise from the Booster and these were not sufficient to allow the locos to work off the power grid. The class formed a "proof-of-concept" for booster-based electric locomotives. All three were withdrawn in the winter of 1968/1969 without receiving TOPS numbers, although 20001 received BR "Rail Blue" for its final years. None survived to preservation. |
|
Type of Locomotive |
Electric |
Builder |
SR Ashford Works BR Brighton Works |
Build Dates |
1941 to 1948 |
Total Built |
3 |
Tractive Effort |
40,000 to 45,000 lbf |
Power Output |
1,470 hp |
Top Speed |
75 mph |
Wheel Configuration |
Co-Co |
Operated By |
Southern Railway British Railways |
Main Duties |
Prototype |
In Service Until |
1968 |
Surviving Examples |
0 |