The Boeing 707 made its first flight in 1957.
The prototype, known as the Boeing 367-80 or “Dash 80,” flew on July 15, 1954, but the production 707 itself first flew on December 20, 1957. This distinction causes frequent confusion because the earlier prototype formed the basis for the commercial airliner.
The 707 was Boeing’s first successful commercial jetliner. It used four engines and swept wings, combining much higher speed with smoother long-distance travel than piston-powered airliners. Pan Am introduced the passenger 707 into scheduled service in 1958.
The aircraft helped establish Boeing as a dominant commercial-airliner manufacturer. It also shared important design ancestry with the military KC-135 tanker, although the two aircraft were not identical. The 707 remained an important passenger and cargo type for decades.