DC-8 Early Design Phase
Douglas secretly began jet transport project definition studies in mid-1952. By mid-1953 these had developed into a form similar to the final DC-8; an 80-seat, low-wing aircraft with four Pratt & Whitney JT3C turbojet engines, 30° wing sweep, and an internal cabin diameter of 11 feet (3.35 m) to allow five-abreast seating.
Maximum weight was to be 190,000 lb (86 metric tons), and the range was estimated to be about 3,000–4,000 miles (4,800–6,400 km).
Douglas remained lukewarm about the jet airliner project but believed that the Air Force tanker contract would go to two companies for two different aircraft, as several USAF transport contracts in the past had done. In May 1954, the USAF circulated its requirement for 800 jet tankers to Boeing, Douglas, Convair, Fairchild, Lockheed, and Martin. Boeing was just two months away from having their prototype in the air. Just four months after issuing the tanker requirement, the USAF ordered the first 29 KC-135s from Boeing.
Besides Boeing’s ability to provide a jet tanker promptly, the flying-boom air-to-air refueling system was also a Boeing product from the KC-97.
Six-abreast economy cabin, 1973. Donald Douglas was shocked by the rapidity of the decision which, he said, had been made before the competing companies even had time to complete their bids. He protested to Washington, but without success. Having started on the DC-8 project, Douglas decided that it was better to press on than give up. Consultations with the airlines resulted in several changes: the fuselage was widened by 15 inches (38 cm) to allow six-abreast seating. This led to more massive wings and tail surfaces and a longer fuselage.
The DC-8 was announced in July 1955. Four versions were offered, to begin with, all with the same 150-foot-6-inch (45.87 m) long airframe with a 141-foot-1-inch (43.00 m) wingspan, but varying in engines and fuel capacity, and with maximum weights of about 240,000–260,000 lb (109–118 metric tons).
Douglas steadfastly refused to offer different fuselage sizes. The maiden flight was planned for December 1957, with entry into revenue service in 1959. Well aware that they were lagging behind Boeing, Douglas began a significant marketing push.