The 205s were the first of two classes of Diesel Electric Multiple Unit designed to work the many unelectrified routes and branches of the British Rail Southern Region, following the desire to withdraw steam from the network. They were designed based on the existing Class 414 2HAP, but with a diesel generator to provide power to a set of electric traction motors in place of third rail pick up shoes. The Class 207s came later and were based on the more up to date Class 421 4CIG with the cab ends made of steel reinforced fibreglass. Other design changes were also implemented, including changes to the mounting arrangements for the diesel engine. 

Both classes worked various services across the Southern region throughout their lives, their numbers dwindling as lines began to close or undergo electrification work in the years leading up to sectorisation. Under Network SouthEast both classes were reduced to working the Marshlink line between Hastings and Ashford, as well as the Oxted line from London to Uckfield. Both classes were replaced with new Class 171 Turbostars in 2004, as a part of Southern’s plan to completely replace their slam door fleet with more modern units. 205205 survived in passenger service into this era, however was withdrawn after a power failure in June 2004 a few months before the fleet were withdrawn.

205205 is a very special unit, being the only unit to undergo a large refurbishment in 1979. In this refurbishment the saloon was modified and all first class seating was removed, gangways between the coaches were added as well as new lighting and PA system. The control systems were altered with a 4-notch master controller similar to a Class 423 4VEP being fitted in place of the original 7-notch one, which allowed the unit to work within the standard Southern Region Multiple working system. Having spent many years in preservation at various locations 205205 now lives at the Epping and Ongar railway in Essex.

(1) BR Blue 205018 departing Worth Halt on the Lavender Line. (2) Hastings Diesels Class 201 1001 at London Victoria working a charter service. (3) BR Green 205033 at Isfield on the Lavender Line. (4) BR Blue Grey 207017 at Eridge on the Spa Valley Railway. (5) BR Blue 205018 at Isfield on the Lavender Line.

Additional Information on the Class 205 and SR DEMU design

Blood and Custard - 2H/3H/3T Hampshire Units

https://www.bloodandcustard.com/BR-2H-3H-3T-Hampshire.html

Blood and Custard - 3D East Sussex Units

https://www.bloodandcustard.com/BR-3D-EastSussex.html

1111 to 205205 - The Story of a Thumper unit

https://www.eorailway.co.uk/the-railway/rolling-stock/205205-history/

Hastings Diesels Limited

https://www.hastingsdiesels.co.uk/