The Boeing 707 is a four-engine jet airliner associated with the expansion of long-distance jet passenger service in the late 1950s. The production 707-120 first flew on 20 December 1957, following the earlier Boeing 367-80 technology demonstrator.[1]
From demonstrator to airliner
The 367-80, known as the Dash 80, first flew in July 1954. The subsequent production airliner had a wider cabin. Pan American pressed Boeing to accommodate six-abreast seating, making the passenger cabin a central commercial consideration alongside speed and range. The demonstrator and the production 707 therefore represent different stages of the programme.[2]
Jet airline service
Pan American began international 707 services in October 1958. National Airlines then introduced domestic jet service using an aircraft borrowed from Pan Am, while American Airlines began operating its own 707s in January 1959. Faster transcontinental journeys reduced travelling time compared with piston-powered airliners and helped stimulate demand for jet travel.[2]
Propulsion and range
The earlier aircraft used turbojet engines. Later JT3D turbofan installations increased airflow around the engine core and reduced fuel consumption. Together with additional fuel capacity, improvements to the 707-300 supported nonstop transatlantic operations. The family consequently spans different propulsion standards rather than one fixed engine arrangement.[3]
Related 720
Boeing developed the 720 for shorter routes and shorter runways. It shortened the fuselage and revised the wing leading-edge arrangement, subsequently adding turbofan engines. Boeing built 154 examples between 1959 and 1967. The 720 belonged to the same broad design lineage, but its operating objectives differed from the longer-range 707s that became prominent on intercontinental services.[4]