Jimmy was a LMS Princess Coronation Class
Jimmy is based on the London Midland and Scottish Railway (LMS) Coronation Class. Designed by William Stanier and built at Crewe Works between 1937 and 1948, these 4-6-2 tender locomotives were built for express passenger services and, on test, were the most powerful steam locomotives ever used in Great Britain. They were in service until 1962-1964, when they were withdrawn from service and scrapped en masse. Three examples have been preserved, including No. 6229 Duchess of Hamilton at the National Railway Museum. Duchess is also based of this class!