British Rail Class 306


The British Rail Class 306 was a type of electric multiple unit introduced in 1949. It consisted of 92 three-car trains which were used on newly electrified suburban on the Great Eastern Main Line between and London Liverpool Street.

Overview

Class 306 trains were built to a pre-World War II design by Metro Cammell and Birmingham Railway Carriage and Wagon Company and were equipped with English Electric traction equipment. Each carriage featured two sets of twin pneumatic sliding passenger doors, which could be opened by either the guard or the passengers, who could use buttons fitted inside and outside the doors. The order was placed by the LNER in 1938 but official delivery did not commence until February 1949.
When built the trains were energised at 1,500 V direct current which was collected from overhead wires by a diamond pantograph located above the cab on the Motor Brake Second Open vehicle.
In the early 1960s, the overhead wires were re-energised at 25,000 V alternating current and the trains were rebuilt to use this very different electrical system. A transformer and rectifier unit was fitted to the underframe between the bogies of the intermediate carriage and the pantograph, now a more modern Stone Faiveley AMBR design, was moved to the roof of this carriage. Because this reduced the headroom inside the train, the guard's compartment was relocated to be directly below the pantograph. The trains were then re-numbered 001-092 with the last two digits of each carriage number the same as the unit number.

Operation

Units being made up of three coaches, trains were usually formed on three units although off-peak trains formed of only two units could be seen. This meant that the standard formation could carry 528 seated passengers plus another 696 standing, making 1,224 passengers, compared with about 1,000 passengers in the steam trains that they replaced.
There is a record of a single three-coach unit hauling a Class 47 and train into Chelmsford after the locomotive failed on a London Liverpool Street to Norwich express.

Withdrawal and preservation

The Class 306 trains were withdrawn in the early 1980s, with 306017 preserved at Ilford depot. It has been repainted in a near original green livery, albeit with a yellow warning panel on the front to comply with present-day safety regulations. In the early 2000s, it was restored to operational condition by First Great Eastern.
The unit was in store at MoD Kineton awaiting the resolving of issues such as asbestos contamination. The contamination was removed at Eastleigh Works and the unit was transferred by rail to the East Anglian Railway Museum in June 2011 for display as an exhibit, under a 4-year loan agreement from the National Railway Museum. It was moved to Locomotion: the National Railway Museum at Shildon in October 2018 so it can be assessed before restoration. It is scheduled to move to York when space becomes available.