Britain's First "Double Deck" Train Now In Service -- Passengers in the novel "double decker" waiting to commence their first trip in the new train.Britain's first "double deck" electric train is now in service between London and Dartford, Kent. The train - of eight coaches - has seating accommodation for 1,104 passengers against the 772 carried by the older type. The train has been designed in an effort to solve the problem of getting the rush-hour crowds away from the City to their suburban homes in comfort and with speed. November 1, 1949. (Photo by S&G).