Hawker Siddeley HS 748 Paper ended most military manned-aircraft development in the UK, and Avro decided to re-enter the civilian market. The Vickers Viscount had the larger end of the short-haul market, and Avro therefore decided to design a smaller regional airliner powered by two Rolls-Royce Dart turboprop engines, intended to replace the many DC-3 Dakotas that were by then reaching the end of their economic lifespan. Original plans were for a 20–30 seat aircraft with a similar configuration to the Fokker F27, but talks with potential customers soon led to a low-wing 40-seat design being chosen for the 748 project. Avro was not
Vickers Type 170 Vanguard Vickers Type 170 Vanguard The Vickers Vanguard was a 1920s British airliner developed by Vickers Limited from the Victoria. Developed from the earlier Victoria with the introduction of a wider fuselage, the Vanguard was a 22-passenger twin-engined biplane. Originally built for the Air Ministry as the Type 62 the aircraft powered by two 450 hp Napier Lion engines first flew on 18 July 1923. It was re-engined in 1925 with two 650 hp Rolls-Royce Condor IIIs and re-designated the Type 103. When it was handed over to Imperial Airways in 1925 it was described as the "World's largest passenger aeroplane".