CLASS 313 EMUs have been featured frequently in the pages of both The Railway Magazine and The Railway Observer since their introduction to service in 1976. They had their genesis in the 4-PEP (Class 445) and 2-PEP (Class 446) suburban EMUs, the prototypes of which entered service in 1971. However, there were no production models.
The ‘313s’ were British Rail’s first dual-voltage EMUs, having both a pantograph for 25kV overhead AC lines and contact shoes for 750V DC third-rail systems. This gave them a huge degree of operational flexibility in comparison with older EMUs.
They were ordered in conjunction with electrification of the Great Northern route from King’s Cross to Royston via the East Coast Main Line and the Hertford Loop. They were specifically intended for inner suburban services, with Standard Class seating only, therefore comfort was not a priority and the units quickly became unpopular with passengers.
They were also used on the former London Transport Northern Line branch from Finsbury Park to Moorgate using a 750V DC third-rail system, the restrictive tunnels on this route meaning the units were built to a smaller loading gauge.