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 14 hours and 38 minutes with one intermediate landing. However, it was never used as a commercial airliner due to the onset of World War I. In 1915, the first airliner (for commercial use) was used by Elliot Air Service. The aircraft was a Curtiss JN 4, a small biplane which was used mainly in World War I as a trainer. Later, it was also used as a tour and familiarization flight aircraft in the early 1920s. In 1919, after World War I, the Farman F.60 Goliath, originally designed as a long-range heavy bomber, was converted for commercial use into