R3850 61XX Class 'Large Prairie' 2-6-2T 6147 BR Green Late Crest Steam LocomotiveIn 1903, George Churchward, Chief Mechanical Engineer of the Great Western Railway, embarked upon his locomotive improvement scheme with three types of 'standard' class engines, of which his 2 6 2T design was destined to become probably the GWR's most useful locomotive, lasting in traffic until the last month of Western Region steam operations in December 1965. The Class prototype, No. 99, spent two years working across the GWR system and the lessons