Boeing 377 in 1950 and the first order for the 707 in 1955, Boeing was shut out of the commercial aircraft market. In the mid-1950s technology had advanced significantly, which gave Boeing the opportunity to develop and manufacture new products. One of the first was the guided short-range missile used to intercept enemy aircraft. By that time the Cold War had become a fact of life, and Boeing used its short-range missile technology to develop and build an intercontinental missile. In 1958, Boeing began delivery of its 707, the United States' first commercial jet airliner, in response to the British De
Boeing 720 costs, which allowed it to be successful despite few sales. The company built 154 Boeing 720s and 720Bs from 1959 to 1967. The 720's wing modification was later added on the -120B and on -120s retrofitted to the B standard. The Boeing 720 is a four-engined low-wing cantilever monoplane. Although it was similar to the Boeing 707, compared with the 707-120, it was 9 ft (2.73 m) shorter in length, and had a lighter structure through use of lighter forged metal parts and thinner fuselage skins and structures. The rearmost of the 707's over-wing emergency exits was deleted on each