A TRS19 and above steam enginespec for the GWR Castle class 4-6-0 express passenger locomotive with the higher degree of superheating as implemented by F W Hawksworth and double chimney designed at Swindon Works and fitted to some locomotives in the late 1950s and early 1960s. Boiler pressure: 225psi. Tractive effort: 31625lbs. This spec. uses real world data and will perform most accurately if used with Stovepipe's e-specs for British rolling stock. Please see the included readme.txt for further information.