In the mid 1980s the need came to replace the Reps and TCs on the Bournemouth and Weymouth line. Although at this time the 4 Rep MBSOs were only between 10 and 18 years old - all quite young for Southern EMU stock - the majority of cars within these units started their lives as locomotive hauled stock in the 1950s. Additionally new low cost technology now permitted the line between Bournemouth and Weymouth to be electrified - albeit with compromises. The opportunity at long last was taken to give the Southern modern stock on a par with that in use in other regions because there was some embarrassment that whilst the final Reps were being constructed in 1974 to Mk1 design it was being done alongside Mk3 stock for elsewhere. Twenty four 5 car units of 23 metre Mk3 hauled coach stock design (but with power operated swing plug doors) were selected with a central power car supplying all traction, air-conditioning and door power supplies. Fortunately previous construction of Mk3 stock for Iarnrod Eireann which included some generator vans had proved that the successful Mk3 design was capable of carrying the weight required by traction and power equipment. However despite the new body shells the long Southern tradition of re-using equipment prevailed since the 4 Rep traction motor and control equipment was far from life-expired. This required Reps to be withdrawn before the 442s became available and led to temporary formations being used.

All units were formed Driving Trailer Composite (DTC), Trailer Standard (TS), Motor Buffet Luggage Standard (MBLS), Trailer Standard Wheelchair (TSW) and Driving Trailer Standard (DTS). The fact that there was to be only one type of unit would lead to there being two catering cars in a ten car formation, however because of the restricted power supply between Bournemouth and Weymouth (caused by the low cost nature of the scheme) only one unit could work this end of the line.

photograph by Colin Duff

photograph by Colin Duff

Deliveries of new units was slower than planned leading to use of the remaining Reps and TCs longer than expected. The first unit was introduced to service on 16 May 1988 and the last unit commissioned on 25 February 1989. The first thirteen units were constructed with luggage areas either side of the guard's office however thereafter the area next to the buffet was constructed as a lounge commonly referred to as the "snug". Earlier units were subsequently rebuilt with a snug. In 1989 the cab end jumper hatch covers were removed following injuries to staff because they were heavy and they were replaced by lighter covers in 1990. Controlled emission toilets were retro-fitted to all units by the end of 1992.

The 442 units (the designation 5 Wes is less commonly used) with their stylish looks and internal comfort proved to be popular and a great success with passengers, the only poor aspect being only two doors per car - expected on long distance Intercity stock but not on the relatively short haul intensively used Southern.

photograph by Colin Duff

photograph by Michael Taylor