© Michael Taylor
Class 4DD 4-car EMU set #4001.
4001 at Charing Cross station in June 1970.
There were only 2 4 car units built to the design of O. V. S. Bulleid in 1949 and usually worked together during rush hours and stored at Slade Green during the day. They were built to carry the equivalent load of a 10 coach train without the necessity of extending the platforms of suburban stations. They were restricted in the routes that they could work because they were built to the outside limit of the loading gauge. These units were withdrawn on October 1, 1971 after 22 years service so were in fact a success even though no more units were built.
The upper and lower compartments were staggered and there was a short flight of leading from the lower to upper. This arrangement led to delays in passenger entering and leaving the train at it was allowed extra time at stations. No more units were built and British Railways embarked on a platform lengthening programme.
One of the Driving Motor Brake seconds has been preserved and the website is at http://members.tripod.com/~dart75/bdds.htm