Transport for LondonD' stock
'D' stock
District Line (All sections except between Edgware Road & High Street Kensington)
Refurbished by Bombarider Transportation UK, Derby 2006-2008.
They were manufactured by Metro-Cammell of Birmingham. The trains comprise two three-car units - "driving motor" cars, trailers and driving or non-"driving motor" cars.
The fleet of 75 six-car all aluminium D78 stock was introduced in stages between 16/01/1980 and 1983.
They are similar in length to the seven car trains they replaced, each car being longer than usual. This had the advantage of lessening the amount of wheel-sets required per train, thereby reducing maintenance costs and through being lighter lessening train noise and vibration.
Seating is mainly longitudinal. There are concealed fans in the ceilings, which were later boosted by additional fans. Together with opening quarterlights a high degree of comfortable ventilation was afforded.
The D78 stock shares many similarities with the 73 tube stock that runs on the Piccadilly line, particularly in its traction package and wheelsets. Uniquely for the surface stock, the D78 stock has Tube sized wheels. Traditionally, surface stock has always had 1067mm wheels, whereas Tube stock has 790mm wheels. The smaller wheels allowed there to be more headroom in the cars, and was also an attempt to reduce maintenance costs by reducing the different types of wheels and bogies in use.
Traction brake controls comprise a right-hand "fore and aft" vertical lever incorporating the "dead man" device, instead of the previous left hand rotary operated controller.
For the first time with surface stock, the doors consist of four pairs of single leaf doors per side. Seating is mostly longitudinal with a double pair of transverse seats in the centre of each car.
The Fleet is currently undergoing refurbishment by that see the fleet finally painted in London Undergound Corporate colours. The refurbshment programme also includes a complete interior refresh, including car end windows and CCTV being added to increase security. Significant improvements to the Passenger information system are being made with saloon dot matrix station/destination displays and a new digital voice annoucer.
There are three types of D78 car - DM ("driving motor" cars - fitted with drivers controls and traction motors), UNDM (Uncoupling non-"driving motor" cars - Fitted with traction/control equipment but no drivers controls or accommodation, and fitted with a small cabinet allowing uncoupling and shunting), T (Trailer coach with no driving controls or traction equipment)
| DM | UNDMM | T | |
|---|---|---|---|
| Length | 60ft 3.25in | 59ft 5.5in | 59ft 5.5in |
| Height | 11ft 10.5in (3.62m) | 11ft 10.5in (3.62m) | 11ft 10.5in (3.62m) |
| Width | 9ft 4.25in (2.85m) | 9ft 4.25in (2.85m) | 9ft 4.25in (2.85m) |
| Seating | 44 | 48 | 48 |
| Weight | 27.46 tonnes | 26.11 tonnes | 18.40 tonnes |
| Seating capacity per train | 280 | ||
| Standing capacity per train | 1092 | ||
| Train capacity - six cars | 1372 | ||
The "D" stock is currently the oldest stock running on the Underground that has not been refurbished, but plans were being advanced during 2002 with the public being invited to comment upon a prototype refurbished carriage before a package of work is instigated.
