Class A3 (Steam locomotives)

The London and North Eastern Railway (LNER) Gresley Classes A1 and A3 were 4-6-2 "Pacific" steam locomotives designed by Nigel Gresley for passenger service. They were initially intended for use on the Great Northern Railway (GNR), but became a standard design on the LNER after the amalgamation of 1923. The change in class designation from A1 to A3 reflected the fitting to the same chassis of a higher pressure boiler with a greater superheating surface and a small reduction in cylinder diameter, leading to an increase in locomotive weight and power. Eventually all but one of the A1 locomotives were rebuilt in this way, with no. 4470 being completely rebuilt as a Class A1/1. The names for the locomotives came from a variety of sources. The first, Great Northern, was named after its parent company. Others were given the names of high-ranking railway officials, but most were given the names of famous racehorses. One was named after the company's most famous long-distance passenger train, the Flying Scotsman. Only one member of the class survives: 4472 Flying Scotsman, which is preserved in the National Railway Museum's National Collection.