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
Airliner US, and later designs like the BAC 1-11, Vickers VC10, and Hawker Siddeley Trident although successful would be unable to win a substantial part of it back again. Another committee was formed to consider supersonic designs, STAC, and worked with Bristol to create the Bristol 223 design for a 100-passenger transatlantic airliner. However, this was going to be so expensive to produce that the effort was later merged with similar efforts in France to create the first supersonic airliner—the Concorde. The United States, conversely, gained a huge advantage in design and production in the airline industry in the years leading