MIAMI – Today in Aviation, the original 707-120 developed by Boeing Commercial Airplanes as its first jetliner performed its maiden flight in 1957.
The Boeing 707-120 was made from the Boeing 367-80 prototype that the company flew in 1954. Boeing 707 service started regularly on October 26, 1958, with Pan American World Airways, up until 1979. The Boeing 707 quad jet has a swept wing with enveloped motors. Its larger fuselage cross-section allowed six-abreast economy seating, retained in Boeing models 720, 727, 737, and 757 later.
The long-range narrow-body Boeing 707, with a maximum take-off weight almost twice as high and a maximum range almost twice as long as other aircraft from the time, is accredited to have kickstarted the jet age due to the fact that it introduced the most prolific design family in the industry, one that advanced relentlessly by adding another 10 models to its diverse lineup.
The Inception of the Boeing 707
The Boeing 707 had a military pedigree, as the company was known then for its military aircraft manufactured during and after World War II.
After World War II, the British spearheaded commercial jets with the de Havilland Comet, but structural problems led to catastrophic accidents, and the Comet has grounded the Comet along with the enthusiasm for commercial jetliners. However, Boeing Company President William Allen and his management decided to “bet the company” on a vision that the future of commercial aviation was jets.
The Boeing 707 began as an in-air refueling tanker prototype for the company, and further development led to the KC-135A Stratotanker and finally to a four-engine passenger aircraft powered by turbo-jet Pratt & Whitney small-diameter engines, each with a thrust of about 50 kilonewtons. By comparison, each of the two turbofan high-bypass General Electric GEnx-1B engines powering today’s Boeing 787 delivers more than 300 kN at takeoff.
Inspired by the work of Adolph Busemann of Germany, the designers of the Boeing 707 swept its wings further back than the de Havilland team did with the Comet. As the 707’s wings were swept back at 35 °, the aircraft showed an undesirable “Dutch roll” flying characteristic that manifested itself as an alternating combined yawing and rolling motion.
An interesting design decision was that while the Comet’s four engines were embedded in the wing by De Havilland, causing drag, Boeing had a more unusual concept, which it first tested on the company’s 367-80 or “Dash 80” prototype (featured image) and integrated into the 707: it slung the engine pods under the wing. This innovative design made the 707’s pylons direct the airflow over the wing on a straight path. This engine placement decision has been replicated by manufacturers ever since.
The Legacy of the Boeing 707
In the 1960s, it dominated passenger air transport and remained prevalent in international, transcontinental, and transatlantic routes, as well as in freight and military applications through the 1970s.
The first successor, in 1963, was the three-engine Boeing 727; the four-engine 747, launched in 1969, was perhaps the most innovative concept in modern aviation; and the new Boeing addition, the revolutionary 787 Dreamliner, launched in 2011, was the first aircraft to be made of composites of carbon fiber, capable of flying more than 17 hours on routes.
On December 20, 1957, the first Boeing 707–120 flight took place, and FAA certified the type on September 18, 1958. The first Iven C. Kindercheloe Award for test flights that resulted in the 707 certification was awarded to both test Pilots Joseph John “Tym” Tymczyszyn and James R. Gannett.