Turboprop on 20 September 1945. From their experience with the Trent, Rolls-Royce developed the Rolls-Royce Clyde, the first turboprop engine to be fully type certificated for military and civil use, and the Dart, which became one of the most reliable turboprop engines ever built. Dart production continued for more than fifty years. The Dart-powered Vickers Viscount was the first turboprop aircraft of any kind to go into production and sold in large numbers. It was also the first four-engined turboprop. Its first flight was on 16 July 1948. The world's first single engined turboprop aircraft was the Armstrong Siddeley Mamba-powered Boulton
Vickers River Tyne. Armstrongs shipbuilding interests became the "Naval Yard", those of Vickers on the west coast the "Naval Construction Yard". Armstrong Whitworth Aircraft was not absorbed by the new company. In 1928 the Aviation Department became Vickers (Aviation) Ltd and soon after acquired Supermarine, which became the "Supermarine Aviation Works (Vickers) Ltd". In 1938, both companies were re-organised as Vickers-Armstrongs (Aircraft) Ltd, although the former Supermarine and Vickers works continued to brand their products under their former names. 1929 saw the merger of the acquired railway business with those of Cammell Laird to form Metropolitan Cammell Carriage and Wagon (MCCW);