LNER Class A4
The Class A4 is a class of streamlined 4-6-2 steam locomotive designed by Nigel Gresley for the London and North Eastern Railway in 1935. Their streamlined design gave them high-speed capability as well as making them instantly recognisable, and one of the class, 4468 "Mallard", holds the world record as the fastest steam locomotive. Thirty-five of the class were built to haul express passenger trains on the East Coast Main Line route from London Kings Cross via York to Newcastle, and later via Newcastle to Edinburgh, Scotland. They remained in service on the East Coast Main Line until the early 1960s when they were replaced by Deltic diesel locomotives. Several A4s saw out their remaining days until 1966 in Scotland, particularly on the Aberdeen - Glasgow express trains, for which they were used to improve the timing from 3.5 to 3 hours.
4-4-2 (locomotive)
The locomotives were cross balanced and ran on drivers. They had an oil-fired grate and a rated boiler pressure of , which gave the boiler a high capacity in relation to the cylinders. Designed for a light-weight train of five to six passenger cars, they were considered as probably the fastest steam locomotives ever built in the United States, possibly capable of matching any locomotive in the world. The fleet covered their schedule in 400 minutes with several stops en route, at an average speed of more than on some sections and often arriving with one or two minutes to spare.