Class 442 5-WES Wessex Electrics

The Class 442 was built for Network South East services out of London Waterloo to Weymouth to replace Class 432 and some Class 33 + 4-TC services [1] (electrification of the route being extended from Bournemouth to Weymouth in the mid-1980s [2]). The Class 442s, which became known as the Wessex Electrics [3], were designed around the Mark 3b coach with a single power vehicle in a five car set. In keeping with Southern Region tradition the Class 442 included equipment recycled from the Class 432 units they were replacing. Equipment re-used included the traction system.
London Victoria bound

Information
Number built: 120 (24 5-car sets)
Built: 1988-89
Builder: BR Derby
Engine: 4 EE546 traction motors (750c DC third rail)
Power: 1, 600 hp (1, 200 kW)
Formation: Driving Trailer Standard (DTS)+Trailer Standard Open (TSO)+
Motor Luggage Composite (MLC)+Trailer Standard Wheelchair (TSW)+DTS

The Class 442s had some initial problems especially with hot axle boxes but became popular with passengers. The Class 442 was transferred to South West Trains following privatisation but were replaced by Desiro stock in 2007. They were rebuilt and modified at Wolverton and used on the Gatwick Express services out of London Victoria and some Southern services. They were replaced by Class 387s in 2017, however this was not to be the end of the Class 442 story.

There were various schemes and suggestions to use the 442s, including even a proposal to use them as hauled stock on trans Pennine routes! Finally it was announced that the new South Western Railway franchise (which replaced South West Trains in 2017) was to use refurbished sets on London Waterloo to Portsmouth services. Eighteen of the units were to be used by SWR, however their time in service was short (just a few months) due to technical issues and the drop in demand due to Covid. Despite an expensive retractioning and refurbishment of half of the fleet the Class 442s were withdrawn in 2021 and will be replaced by Class 458s [4]. It is now unlikely they will return to mainline service.
442 423 at London Victoria
Gatwick Express 442 clears Clapham Junction

Another Gatwick Express 442 at Clapham Junction

[1] Brian Haresnape & Alec Swain, Third Rail DC Electric Multiple Units (Ian Allan, 1989) p. 80
[2] Colin J Marsden, DMU and EMU Recognition Guide (Ian Allan, 2013) p. 342
[3] John Balmforth, South West Trains (Ian Allan, 2011) p. 60
[4] "SWR abandons 442s but retains 458s", Modern Railways (May 2021) p. 86