The World Record Steam Locomotive ...
The DRG covered only a small, exclusive market segment for long distance passenger service with the express passenger service provided by the diesel powered rail car trains. Locomotive-hauled trains continued to form the backbone of the passenger service. They offered far more capacity, more room, comfort, and service, for example: dining and sleeping cars. And yet more speed was required for these trains too. The locomotive builders developed suggestions for a steam locomotive that was planned for a speed of 175 km/h or 109 mph. The DRG decided on a coal-fired three-cylinder locomotive with a 4-6-4 wheel arrangement. Its dimensions were immense: The driving wheels had a diameter of 2.30 meters or 90-9/16 inches, the boiler tubes were 7 meters or 275-9/16 inches long, and the power output reached 2,360 pounds per square inch.
Road number 05 002 surpassed the world speed record for steam locomotives between Hamburg and Berlin with a speed of 200.4 km/h or 125.25 mph in a test run on May 11, 1936, a record that still stands today. The fact that this value was never surpassed proves the limits of this technology. The immense moving masses of cylinders, drive rods and side rods did not permit higher speeds. The fireman was hard pressed to keep the boiler steamed up.
The two units built in 1935 have a very futuristic look with their red streamlining. As a status symbol of the DRG, they were used in express passenger service and bore the Olympic rings for a while.