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
Jet airliner turbofans, which are quieter and more fuel-efficient. The first airliners with turbojet propulsion were experimental conversions of the Avro Lancastrian piston-engined airliner, which were flown with several types of early jet engine, including the de Havilland Ghost and the Rolls-Royce Nene. They retained the two inboard piston engines, the jets being housed in the outboard nacelles. The first airliner with jet power only was the Nene-powered Vickers VC.1 Viking "G-AJPH", which first flew on 6 April 1948. The early jet airliners had much lower interior levels of noise and vibration than contemporary piston-engined aircraft, so much so that in 1947,