The Boeing 720 is a jet airliner. It has two rows of seats, which means that it is a narrow-body airliner. It has four engines. The Boeing 720 was designed by Boeing in the 1950s. It was based on the Boeing 707, but the 720 is shorter and cannot fly as far. The 720 first took off in November 1959. Airlines began to use it in July 1960.
Two versions of the plane were made. The first one had Pratt & Whitney JT3C turbojet engines and was first used in 1960. The second one is called the 720B, and it has Pratt & Whitney JT3D turbofan engines. It was first used in 1961. Some 720s were changed to 720Bs.
Only 154 Boeing 720s were built, but it still made Boeing a lot of money because it did not cost a lot to design.
The Boeing 720 was replaced by the Boeing 727.