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 V-1000 on the overall project. Construction of the prototype was performed at Vickers' facility at Wisley Airfield, Surrey; flight trials would have also been based there. By November 1956, over £4 million had been spent on the V-1000 project; the first prototype had also reached 80 per cent completion. It had been estimated that the VC7 would have been in operational service as early as 1959, the same year in which the first V-1000s were projected to be delivered to the RAF. If it had entered commercial service as envisioned, it would have been the first turbofan-equipped airliner to serve long-haul