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-Armstrongs A1E1 tank. One of the company's most important designs was the Valentine Infantry Tank, produced in the thousands in World War II. The military vehicle manufacturing interests were divested into Vickers plc, and would later pass to Alvis Vickers, now part of BAE Systems Land and Armaments. "Notable Vickers-Armstrongs military vehicles include;" Vickers formed its Aviation Department in 1911. The aircraft interests of Armstrong Whitworth were not acquired in the merger and later passed to the Hawker Aircraft group. In 1928 the Aviation Department became Vickers (Aviation) Ltd and soon after acquired Supermarine Aviation Works, which became the Supermarine Aviation