The D1 class were a class of diesel locomotives built by Commonwealth Engineering, Granville with English Electric traction equipment for Australian Iron & Steel's, Port Kembla steelworks in 1950–1951.
History In May 1950, D1 became the first diesel to operate on an Australian main line. The eight D class locomotives hauled trains on Australian Iron & Steel's, Port Kembla until a downturn in the early 1980s saw most of the class withdrawn."Australian Iron & Steel" Railway Digest October 1986 pages 299-303750 Class (Port Kembla) Railpage D6 and D7 were reactivated with the former remaining in service until 2004.
Three have been preserved:Port Kembla - Diesel Locomotive Fleetlisting Light Rail Research Society of Australia D1 by the NSW Rail Museum, Thirlmere. D6 by the Lithgow State Mine Heritage Park & Railway, Lithgow. This unit is still stored in Port Kembla. D7 by the former ARHS ACT Division, Canberra.
References
Railway Transportation, November 1951, 'D-E locos and 60-ton cars boost operations for AI&S'