The British Rail Class 321 alternating current (AC) electric multiple units (EMU) were built by BREL York in three batches from 1988 to 1991. The design was successful and led to the development of the similar Class 320 and Class 322 units for use by Strathclyde PTE and Stansted Express (now used by Northern Rail) respectively. The British Rail Mark 3 bodyshell design was also used for construction of the Class 456 direct current (DC) units.
Three sub-classes of unit were built. The first two were built for the Network SouthEast sector, whilst the final batch was built for services around Leeds. These trains have been modified by different rail companies who use them such as Greater Anglia. The modifications include new seats, paintwork, lighting and in carriage announcement boards.
The first batch of 66 EMU trains, built between 1988 an 1990 were classified under TOPS as Class 321/3. Units were numbered in the range 321301-366 and have a maximum speed of 100 mph (161 km/h). Each EMU consisted of four carriages; two outer driving trailers, one of which contained first class seating; an intermediate motor coach with standard class seating only, roof mounted Brecknell Willis High Speed pantograph and four Brush TM2141C traction motors (two per bogie); and an intermediate trailer with standard class seating. The technical description of the formation is DTCO+PMSO+TSO+DTSO. These units were delivered in two groups, with individual vehicles numbered as follows:
Units 321301-346 Units 321347-366
DTCO 78049-78094 78131-78150
PMSO 62975-63020 63105-63124
TSO 71880-71925 71991-72010
DTSO 77853-77898 78280-78299
These EMU trains were built for outer-suburban trains on the Great Eastern Main Line, primarily from London Liverpool Street to Southend Victoria, Ipswich, Southminster, Clacton, Colchester and Braintree. They replaced the ageing slam-door Class 305, Class 308 and Class 309 units on trains to Clacton and Southend-on-Sea, and worked services on the newly electrified routes to Ipswich and Harwich. They also displaced many Class 312 slam-door units to the London, Tilbury and Southend Railway. Some of the Class 309 “Clacton Express” units were retained until 1994, and 24 of the newer Class 312 units were retained long-term to work services to Walton-on-the-Naze and peak services to Clacton, Ipswich and Witham. Units carried the distinctive Network SouthEast livery from new. 321361 was named ‘Phoenix’ in March 2008 at Ilford depot after it was rebuilt at the disused Colchester shed to repair damage caused by an arson attack at Southend Victoria on 10 July 2007.
The second batch of 48 units, built between 1989–90, were classified as Class 321/4. Units were numbered in the range 321401-448 and again have a maximum speed of 100 mph (161 km/h). The formation of these units is identical to that of the first batch, each unit being formed DTCO+PMSO+TSO+DTSO. They were delivered in two groups, with individual vehicles numbered as follows:
Units 321401-430 Units 321431-442 Units 321443-448
DTCO 78095-78124 78151-78162 78125-78130
PMSO 63063-63092 63125-63136 63099-63104
TSO 71949-71978 72011-72022 71985-71990
DTSO 77943-77972 78300-78311 78274-78279
These units were built for outer-suburban services on the West Coast Main Line, from London Euston to Watford, Milton Keynes, Northampton, Rugby, Coventry and Birmingham New Street.
All Units were delivered in Network SouthEast blue, red and white livery. They displaced the recently cascaded Class 317 units dating from 1981 that had themselves only just been introduced to the route to replace Class 310 units….Wikipedia Video Rating: / 5