From
the BBC» On the 17th February 1958, the first “Warship” diesel engine pulled a train from Paddington. Four months later, it was the turn of the Cornish Riviera to get the diesel treatment. The introduction of these locomotives meant the days of the King and Castle steam engines were numbered ...
"Active" was new the month before, but was only active until 1967 that year. One of a class of just 5 (class 41). From
WikiPediaAll five locomotives were withdrawn on 30 December 1967. By this time they were non-standard, even for hydraulic designs, although according to Laira staff reliability was not a problem as many have thought.