Capital Airlines Lockheed Constellations. In 1955 they became the first U.S. operator of the British manufactured, four engine Vickers Viscount, the first passenger turboprop airliner. The Viscount propjets were deployed on the flagship Washington-Chicago route and the airline had planned to fly them on expanded service; however, Capital was mostly stymied by the federal Civil Aeronautics Board (CAB). The CAB also refused Capital a requested subsidy. Still, Capital's passenger-miles in 1957 were 88% more than 1955. On November 14, 1956 a Capital pilot reported seeing a blue-white ball in the sky. The pilot, Captain William J. Hull, was a senior captain who
Vickers Viscount a post-war small medium-range pressurised aircraft to fly less-travelled routes, carrying 24 passengers up to 1,750 mi (2,816 km) at 200 mph (320 km/h). During discussions between the committee and Vickers' chief designer, Rex Pierson, Vickers advocated turboprop power. The committee was not convinced and split the specification into two types, the Type IIA using piston power, which led to the Airspeed Ambassador, and the turboprop-powered Type IIB which Vickers was selected to develop in April 1945. British European Airways (BEA) was involved in the design and asked that the aircraft carry 32 passengers instead, but remained otherwise similar. The