Steam locomotive speed record

What to remember

A downhill stretch of the East Coast Main Line in the United Kingdom served as the track on 3 July 1938, when Mallard, a Class A4 steam locomotive of the London and North Eastern Railway, peaked at 202.6 km/h (126 mph). The data also give a mean speed of 201.2 km/h over half a mile. Built at Doncaster Works to a design by Nigel Gresley, this 4-6-2 Pacific had a streamlined body tested in a wind tunnel, meant for hauling long-distance express passenger trains.

In 1804, the record stood at 8 km/h, set by Richard Trevithick, a ratio of 25.33 against Mallard's figure. The Empire State Express reached 160.9 km/h in 1893, and the German Borsig DRG series 05 002 posted 200.4 km/h in 1936. Mallard edged past it.

In those years the A4s had to run well above 90 mph just to keep time on trains such as the Silver Jubilee and The Coronation. Mallard covered about 2.4 million km before it was retired in 1963, and it is preserved at the National Railway Museum in York.