The London and North Eastern Railway

London and North Eastern Railway

The London and North Eastern Railway was the second-largest of the "Big Four" railway companies created by the Railways Act 1921 in Britain...

 (LNER) Thompson Class B1 is a class of steam locomotive designed for medium mixed traffic work. It was designed by Edward Thompson

Edward Thompson (engineer)

Edward Thompson was Chief Mechanical Engineer of the London and North Eastern Railway between 1941 and 1946.- Biography :Edward Thompson was the son of an assistant master at Marlborough College. He was educated at Marlborough before taking the Mechanical Science Tripos at Pembroke College,...

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It was the LNER's equivalent to the highly successful GWR Hall Class and the LMS Stanier Black Five, a two-cylinder mixed traffic 4-6-0

4-6-0

Under the Whyte notation for the classification of steam locomotives, 4-6-0 represents the wheel arrangement of four leading wheels on two axles in a leading truck, six powered and coupled driving wheels on three axles, and no trailing wheels. This wheel arrangement became the second-most popular...

. However, they had the additional requirement of having to be cheap, as due to wartime and post-war economies, the LNER, never the richest railway company, had to make savings.

Introduced in 1942, the first No.