Armstrong Whitworth Apollo Armstrong Whitworth Apollo The Armstrong Whitworth AW.55 Apollo was a 1940s British four-engine turboprop airliner built by Armstrong Whitworth at Baginton. The aircraft was in competition with the Vickers Viscount but was beset with engine problems and only two were built. The requirement resulted from the Brabazon Committee's Type II design, calling for a small, medium-range pressurized aircraft to fly its less-travelled routes which became Air Ministry Specification C.16/46 for an aircraft able to carry 24-30 passengers over 1,000 mi (1,610 km) at a cruising speed of . The resulting design was the AW.55 Apollo, a low-wing cantilever monoplane with
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".