The Boeing 707 was the first Boeing airliner to feature a swept wing and podded jet engines.
Boeing’s 707 design grew from the company’s 367-80 prototype, known as the Dash 80. The prototype first flew in 1954 and demonstrated the performance advantages of swept wings and jet propulsion. The production 707 then brought those features into widespread commercial airline service.
Its four engines were mounted in pods beneath the wings, a layout that became a familiar pattern for many later jetliners. The swept wing reduced drag at high speed, while the turbojet engines allowed the aircraft to cruise faster and higher than piston-powered airliners.
The phrase “first airliner” can be misleading if applied to every manufacturer worldwide, because other countries were also developing early jet transports. In Boeing’s commercial-aircraft lineage, however, the 707 was the company’s breakthrough jet airliner and a direct successor in influence to the Dash 80 prototype.