Designed by Mr R A Riddles the Clans were a slightly scaled down version of the BR Britannia Class & featured a smaller boiler & cylinders Ten of the class were built at Crewe between 1951 & 1952 with a further 15 planned which were intended for the Scottish & Southern regions however the final 15 were cancelled due to British Railways modernisation plans The 10 completed Clans were shedded at Polmadie Glasgow & Carlisle & were consequently seen working mixed traffic trains on routes between Manchester Liverpool Carlisle Perth & Glasgow The last Clan was removed from service in 1966