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 Viscount TAA. Unstated was the requirement for both airlines to have identical equipment. The first North American airline to use turboprop aircraft was Trans-Canada Air Lines (TCA), with a small fleet of Type 700 Viscounts. Initially, TCA was cautious of the Viscount due to the turboprop engine being a new technology, and there had been a preference for acquiring the piston-engined Convair CV-240 instead; praise of the Viscount from pilots and a promise from Vickers to make any design changes desired by TCA persuaded it to procure the Viscount instead. On 6 December 1954, the first Viscount was delivered to Canada