The South Eastern Railway (SER) O Class (some of which were later rebuilt, becoming the O1 Class) was a class of 0-6-0 steam locomotive designed for freight work, and were the main freight engines of the SER, and later the South Eastern and Chatham Railway (SECR) for a number of years. However, they were displaced by the more powerful C class locomotives following the amalgamation of the South Eastern Railway and London, Chatham and Dover Railway (LCDR) in 1899. This relegated the class to working on the numerous branch lines in Kent, on both passenger and freight work. They worked most notably on the Kent & East Sussex Railway and East Kent Railway, operating coal trains from the Kent coal fields to London, as well as shunting work at such locations as Shepherds Well, Hoo Junction and Ashford. The majority were withdrawn before the outbreak of the Second World War in 1939, and those that remained were slowly withdrawn from nationalisation onwards.
The death knell for the final few members of the class came with the Modernisation Plan of 1955, which closed down many of the branch lines they continued to serve in Kent, which included the branch lines to locations such as Hawkhurst, New Romney, Tenterden and the Kent coal fields. Those lines which remained open generally either lost their freight services or were dieselised. All members of the class had been withdrawn by 1962, and only one member of the class has survived scrapping.
O class may refer to:
The O class consisted of six steam locomotives that operated on New Zealand's national rail network. Ordered from the Baldwin Locomotive Works of Pennsylvania in 1885, three arrived in time to begin work in December 1885, while two more were placed in service in January 1886 and the sixth in February 1886. After almost four decades of service, all six were withdrawn in May 1922. None survived to be preserved, although two engine frames and 5 tenders from O class locomotives are known to exist near Summit on the former Rimutaka Incline.