Number 4468 Mallard is a London and North Eastern Railway Class A4 4-6-2 Pacific steam locomotive built at Doncaster, England in 1938. While in other respects a relatively typical member of its class, it is historically significant for being the holder of the official world speed record for steam locomotives.
Mallard was designed by Sir Nigel Gresley as an express locomotive to power high-speed streamlined trains. Its wind-tunnel-tested,1 aerodynamic body and high power allowed it to reach speeds of over 100 miles per hour (160 km/h), though in everyday service it was relatively uncommon for any steam hauled service to reach even 90mph, much less 100. Mallard was in service until 1963, when it was retired, having covered almost one and a half million miles (2.4 million km).
It was restored to working order in the 1980s, but has not operated since, apart from hauling some specials between York and Scarborough in July 1986 and a couple of runs between York and Harrogate/Leeds around Easter 1987. Mallard is now part of the National Collection at the United Kingdom’s National Railway Museum in York. On the weekend of 5 July 2008, Mallard was taken outside for the first time in years and displayed alongside her A4 sisters, thus reuniting all four A4s extant in the UK for the first time since preservation. She departed the museum for Locomotion, the NRM’s outbase at Shildon on the 23 June 2010, where she was a static exhibit, until she was hauled back to York on 19 July 2011 and put back on display in its original location in the Great Hall.
The locomotive is 70 ft (21 m) long and weighs 165 tons, including the tender. It is painted LNER garter blue with red wheels and steel rims.