BR standard classes

Due to the controversial British Railways' modernisation plan of 1955, where steam traction was abandoned in favour of diesel and electric traction, many of the locomotives' working lives were very short: between 7 and 17 years.

He calculated the costs per drawbar horse power as £13 6s (steam), £65 (diesel), £69 7s (turbine) and £17 13s (electric).

From 1951, BR started to build steam locomotives to its own standard designs, which were largely based on LMS practice but incorporating ideas and modifications from the other constituent companies, continental Europe and North America.

Characteristic features were taper boilers, high running plates, two cylinders and streamlined cabs.

A total of 46 standards have survived - of these, 38 were rescued from Woodham Brothers scrapyard in Wales.