The Class 307 was one of many classes of Electric Multiple Unit built as commuter trains for use on the Great Eastern Main Line during the gradual rollout of electrification across Essex and Suffolk by British Rail in the 1950s and 1960s. Class 307s were the first to be built, with eventually 32 constructed initially as 1500V DC locomotives due to the routes to Shenfield and Southend Victoria using this voltage, eventually however all units were converted to operate on the new standard 6.25 kV/25 kV AC which became the GEML standard when the Class 302s and 308s were introduced. 45 Class 308s were then introduced to operate on the Great Eastern Main Line, and 112 Class 302s were introduced to operate on both the Great Eastern and London, Tilbury & Southend lines as the electrified network expanded during the 1960s.

Many of the Mk1 derived electric multiple units in operation on the Great Eastern Main Line, including the Class 302, 307, 308 and 309, saw replacement in the form of the Class 321 electric multiple unit of 1988. A few of these units would see further use with Regional Railways, with Class 307 and Class 308 units seeing use on electric commuter services out of Leeds. Class 302s meanwhile continued use into privatisation on the London, Tilbury & Southend line, with some of the refurbished units retained until a final farewell of the type on July 4th 1998. Some Class 307 driving vehicles were converted to work with locomotives under the Rail Express Systems Railnet schemeto allow control of locomotives from the rear of the train. Class 302 units were also converted in limited numbers for use by Rail Express Systems, however they continued to operate as multiple units.

Some converted Propelling Control Vehicles have survived in varying states, with two in preservation. However only one vehicle of each of the Class 307 and Class 308 remain, DTBSO 75023 from unit 307123 and BDTC 75881 from unit 308136, both of which are currently at the Colne Valley Railway. Two Class 302 vehicles remain, DTS 75033 from unit 302201 and DTS 75250 from 302207, both of these vehicles are at Mangapps Railway Museum.

(1) BR Blue 75033 (Ex 302201) at Mangapps Railway Museum. (2) BR Blue 75881 (Ex 308136) at Castle Hedingham on the Colne Valley Railway. (3) Class 302 standard class interior. (4) BR Blue 75250 (Ex 302227) at Mangapps Railway Museum. (5) BR Blue 75033 (Ex 302201) at Mangapps Railway Museum.

Additional information on the Class 302 and Class 307

Colne Valley Railway

https://www.colnevalleyrailway.co.uk/

Mangapps Railway Museum

http://www.mangapps.co.uk/