The British Rail Class 307 electrical multiple units were built by BR at Eastleigh Works from 1954-1956. They were initially classified as AM7 before the introduction of TOPS.

Description

Thirty-two of these 4-car units were built to the for services on the Great Eastern Main Line and the London, Tilbury and Southend route. The units were constructed to a similar design to the third-rail EPB units introduced by the Southern Region a few years earlier. However there were several differences, most notably a slightly different front cab (with narrower cab windows) and also a different seating arrangement.

The AM7 units were constructed to operate off the 1500 V DC overhead system used on Eastern Region suburban lines. However, in the late 1950s and early 1960s, these lines were converted to the 6.25 kV / 25 kV AC overhead system, which was adopted as standard, and coincided with the introduction of new AM2 units. Therefore, from 1960-1962 the entire AM7 fleet was extensively rebuilt at Eastleigh Works to allow units to operate off the new voltage system.

All units were formed of four-cars. When originally built, units were numbered in the range 01s-32s, and were composed of two outer driving trailers, an intermediate trailer composite (i.e. with some first-class seating), and an intermediate motor brake. When the units were converted from DC to AC in 1960, they were extensively rebuilt. The work including moving the guard's compartment from the motor coach to one of the driving trailers. At the same time, units were renumbered into the range 101-132.

From 1983-1984 the fleet was refurbished. Work involved replacing all compartments with open saloons, and the fitting of gangways between vehicles within a unit. The first-class seating was also moved from the trailer to the non-brake driving trailer. During this period, units were renumbered 307101-307132.

Details of the vehicle designations are shown below.

Operations

When new, these unit were used on the newly electrified London, Tilbury and Southend (LTS) route, and inner-suburban services on the Great Eastern Main Line, supplementing the earlier AM6 units . In 1960, both of these lines were re-electrified from 1500 V dc to 25 kV AC overhead, neccessitating the rebuild of the fleet.

Following refurbishment in 1983, the fleet saw continued use on both the LTS and Great Eastern routes. From 1986, a few units were repainted in the bold new Network SouthEast (NSE) livery. By 1990, however, the class had been displaced from the LTS route by Class 310 units, themselves cascaded from the West Coast Main Line following introduction of new Class 321/4 units, supplemented temporarily by ex-"Bed-Pan" Class 317 units. the units did not last much longer of the Great Eastern route, following introduction of new Class 321/3 and cascaded Class 312 units.

By 1991, all units had been withdrawn from NSE services. However, five units, nos. 307105/111/120/122/130, were given a reprieve, and were overhauled at Doncaster Works, for use on the newly electrified Leeds-Doncaster line. They received the attractive West Yorkshire Metro maroon livery. The use of these units was intended as a stop-gap until three new dedicated Class 321/9 entered service. The final units were withdrawn in early 1993.

Following withdrawal, large-scale scrapping of the class was delayed as it was intended to rebuild the units as Class 300 parcels units. This plan was dropped in favour of the new-build Class 325 units. However, many of the driving trailer vehicles were eventually rebuilt as Propelling Control Vehicles (see below). The redundant intermediate trailers and motor vehicles were eventually scrapped.

Further Use

Departmental Use

Following withdrawal from service, several units were converted for further use as departmental vehicles. These are listed below.

• Units 307101, 307106 and 307121 were used a crash-test units at Old Dalby, for use in simulated crashes for safety purposes.
• Unit 307118 was converted into test unit 316997.

Postal Conversions

In the early 1990s, the British Rail parcels sector Rail Express Systems identified the need for driving trailers to operate in push-pull mode with a locomotive. This would remove the time consuming process of changing the locomotive to other end of the train to allow it to leave a terminus. These new vehicles were called Propelling Control Vehicles (PCVs), since it was envisaged that they would only be used to propel a train into or out of a terminus, and not used at high-speed or over long distances.

It was decided to convert the vehicles from the many redundant Class 307 vehicles that were stored at various locations around the country. In 1994, two vehicles were rebuilt as prototype PCV vehicles, and under went an extensive testing procedure. In the period 1994-1996, a further 40 redundant driving trailer vehicles were rebuilt by Hunslet-Barclay in Kilmarnock.

The rebuilding work including removal of the windows and slam-doors, the fitting of roller-shutter doors, and modernisation of the cab. The vehicles were given the TOPS code NAA and were numbered in the range 94300-327 (for former DTCOL vehicles)and 94331-345 (for former DTBSO vehicles).

Vehicle nos. 94300/301 were the prototype Propelling Control Vehicles. Due to their non-standard nature, they have since had their push-pull equipment isolated and are used as standard parcels vans. To reflect this change, the two vehicles have been renumbered to 95300/301.

Details of the vehicles converted to PCVs are shown below.

PCV Number   Former Number   Former Vehicle Type   Comments
94300        75114           DTCOL                 Since renumbered to 95300
94301        75102           DTCOL                 Since renumbered to 95301
94302        75124           DTCOL
94303        75131           DTCOL 
94304        75107           DTCOL
94305        75104           DTCOL
94306        75112           DTCOL 
94307        75127           DTCOL
94308        75125           DTCOL
94309        75130           DTCOL
94310        75119           DTCOL
94311        75105           DTCOL
94312        75126           DTCOL
94313        75129           DTCOL
94314        75132           DTCOL
94315        75108           DTCOL
94316        75113           DTCOL
94317        75117           DTCOL
94318        75115           DTCOL
94319        75128           DTCOL
94320        75120           DTCOL
94321        75122           DTCOL
94322        75111           DTCOL
94323        75110           DTCOL
94324        75103           DTCOL
94325        75113           DTCOL
94326        75123           DTCOL
94327        75116           DTCOL
           
94331        75022           DTBSO
94332        75016           DTBSO
94333        75022           DTBSO
94334        75017           DTBSO
94335        75032           DTBSO
94336        75031           DTBSO
94337        75029           DTBSO
94338        75008           DTBSO
94339        75024           DTBSO
94340        75012           DTBSO
94341        75007           DTBSO
94342        75005           DTBSO
94343        75027           DTBSO
94344        75014           DTBSO
94345        75004           DTBSO

Preservation

One vehicle, DTBSO no. 75018 (ex-977708) was preserved by the AC Loco Group for a while at Barrow Hill Engine Shed. However, it due to be scrapped for spare parts. (Still around 04/2005)