BR Diesel Locomotives in Preservation

When British Railways initiated its Modernisation Plan in 1954 it had little experience of diesel locomotives thus initiated a Pilot Scheme to trial combinations of the three elements comprised within a locomotive: the engine, transmission and body. The initial orders for 174 locomotives were placed in November 1955, but changes in Government policy led to bulk orders for most designs being trialled. It was only in 1968, once steam traction had been removed from the network, that BR was able to review the success, or otherwise, of its diesel fleet and decide which designs to withdraw from service. The nascent preservation movement of the time was concerned to preserve steam locomotives whilst only buying diesel shunting locomotives for support roles on heritage lines and it wasn't until 1977 that any effort was made to preserve main line diesels. Fred Kerr's book details those classes which are represented on heritage lines and identifies where possible their location as of December 2016.