Class 458 4-JOP

The Class 458 4-JOP (Juniper Outer-suburban Porterbrook) was built for South West Trains in the late 1990s to replace some Class 411s, although for the Southern 750v DC third rail network they were "future proofed" with provision to support a pantograph and overhead electric collection though do not carry one yet [1]. Their entry into service as 458/0 was fraught with technical difficulties with serious usage on the Waterloo to Reading and Guildford-Ascot routes not happening for several years and after many modifications [2]. The unreliability saw SWT plump for the "Desiro" Class 444/450s instead of more 458s to replace the majority of its "slam door" EMU fleet [3].

Information
Number built: 30 4-car sets
(rebuilds) 36 5-car sets
Built: 1999-02
(rebuilds) 2013-6
Builder: Althom (Washwood Heath)
(rebuilds) Wabtec (Doncaster) & Brush Traction (Loughborough)
Engine: 6 Althom ONIX 800 traction motors
Power: 2, 172 hp (1, 620 kW)
Formation: (original) Driving Motor Composite Open (DMCO)+
Pantograph Standard Open (PSO)+Motor Standard Open (MSO)+DMCO
(rebuilds) Driving Motor Standard Open (DMSO)+PSO+MSO+TSO+DMSO

In 2011 after the withdrawal of the similar Class 460 from the Gatwick Express it was decided to use cars from the 460 to strengthen the 458s as 5 car trains (5-JOP). The trains were also refurbished and rebuilt with an improved appearance and full gangways. 5 "new" 458/5s (as they became known) were also created from spare rebuilt 460 cars. Work is still ongoing on conversions as well as repairs to a fire damaged unit [4] and should be complete sometime in 2016 [5].
SWT 458 535 at Clapham Junction

SWT 458 534 and friend at Clapham Junction

[1] "Class 458" Southern Electric Group <http://www.semgonline.com/gallery/class458_01.html>
[2] Colin J. Marsden, DMU and EMU Recognition Guide (Ian Allan, 2013), p. 356
[3] "Train firm to replace new fleet", BBC News <http://news.bbc.co.uk/1/hi/england/london/3388679.stm>
[4] "Fire damaged 458 under repair", Railways Illustrated Issue 157 (March 2016)
[5] "458/5 programme nears completion", Today's Railways UK Issue 171 (March 2016)