Overview
After a series of trials throughout the North East Area, all of the remaining H1s were rebuilt as A8 4-6-2Ts between 1933 and 1936. During the process of rebuilding, the boiler was modified to include a Robinson-type superheater rather than the original Schmidt superheater. In 1935, further modifications resulted in the A8 boiler being interchangeable with the A6, A7, A8, H1, and T1 classes.
Read more about this topic: LNER Class A8