In the late 1980s, the
Network SouthEast division of
British Rail, which operated the railway network in
South East England, started to develop a new standard train, known as the
Networker. To test out the technical arrangements for the
Networker, a test train was used, converted from former
Class 210 carriages, which were built in 1982 by
Derby Litchurch Lane Works as prototype 'Second Generation' Diesel Electric Multiple Unit (DEMU), but were withdrawn after a few years.
Class 457 Initially the test unit was formed for trials on the system of the
Southern Region, and was numbered 457001. As with all Southern Region
electric multiple units only the last four digits of the unit number were actually carried. The unit formation was:
Class 316 Later, the unit was altered to undertake trials on the
overhead line system used on electrified lines north of the
River Thames. The unit was renumbered as a Class 316 unit, number 316999. To enable it to work on the AC electrification, a pantograph trailer from a
Class 313 unit 313034 was inserted into the set, replacing one of the intermediate trailers. This spare vehicle (no. 67400) was later incorporated into a
Class 455/9 DC suburban unit, replacing a damaged Trailer Second Open (TSO) vehicle. The unit formation was:
Preservation After the AC trials were complete, the set was returned to the Southern Region for storage, minus the Class 313 trailer, which returned to its previous formation. The two driving cars were preserved at the
Electric Railway Museum, Warwickshire, one being resold to the
Eversholt Rail Group and inserted into set
455913 in 2013 after being rebuilt at
Wolverton railway works to replace a carriage destroyed in an accident. The vehicle (67301) was converted to a 455 MSO. The remaining intermediate trailer was scrapped. Vehicle details are shown below: ==Alternative uses of the Class 316 number==