British Rail Classes 445 and 446

On the 4-PEP units the non-driving cars were powered, similar to London Underground practice at the time, but a departure from previous British Railways designs where there had not been any 4-car units with all axles powered.[8] Also introduced for the first time was rheostatic braking with cam-controlled analogue logic, and fluorescent lighting working at 50 Hz. Interior design was open saloons with 2+2 seating, although this was not considered to be finalised until after trial running, and also included communicating doors between coaches and between units, with the driving cars having 2 pairs of sliding doors each and 3 pairs on the non-driving coaches.[8]

4001 at London Waterloo in July 1975

All three units were initially assigned to the South Western Division of the Southern Region, based at Wimbledon Park[9] and Strawberry Hill. Upon arrival, they were used under an extensive testing programme prior to entering full passenger service in June 1973, on services from Waterloo to Chessington South, Hampton Court and Shepperton. In August 1973, all three units were moved to the South Eastern Division, where they worked services from Cannon Street/Charing Cross to Bromley North, Dartford and Sevenoaks. Although capable of being used as a single 10-car formation on the SED, a number of failures saw them returned to the SWD after a month. The Class 446 unit was withdrawn from traffic in August 1974, while the two Class 445s were officially withdrawn from revenue service in May 1977.[10]

After the units were withdrawn from passenger service, they continued to be used by the Research department for further tests.[11] For this purpose, the units and individual carriages were all renumbered into the departmental series. The two Class 446 power cars were teamed with a newly built pantograph trailer and became TOPS Class 920, number 920001.[12] This was then used for the development of Classes 313-315.[13] The two Class 445 four car sets became TOPS Class 935, numbered 056 and 057 in the Southern Region departmental (non-revenue earning) unit series. 056 saw little use, being stored at Wimbledon Park until June 1980, when it was transferred to the Railway Technical Centre at Derby, while 057 was used as a testbed for a number of new bogie designs between 1979 and 1983.[10]

The production-run classes which are most visibly similar to the PEP Stock are the dual voltage 750 V DC / 25 kV AC Class 313, the 25 kV AC Classes 314 and 315, and the 750 V DC Classes 507 and 508. It was also planned that the rolling stock for the services through the proposed Picc-Vic tunnel, intended as Class 316, would have formed part of the PEP family.[14] However, subsequent builds have also drawn heavily on the experience gained by this stock.

The PEP units had three sets of sliding doors on each of the non-driving cars for handling dense inner-suburban traffic. However, the Class 313 and all subsequent builds, including later Mark 3-based units, have only had two sets of doors per car.

PEP coach on the scrapline at Long Marston in 1986

All three units were finally taken out of use in the mid-1980s. None of the cars has survived; 920001 was scrapped in 1987, 056 in 1986 and 057 in 1990.

The unit formations in passenger and departmental service were:

Wikimedia Commons has media related to British Rail Classes 445 and 446.

• History of the PEP units on www.BloodandCustard.com