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 Although only 154 were built, the Boeing 720 and 720B were profitable due to the low research and development costs, being slightly modified versions of the 707-120. They were later replaced by the Boeing 727. The 720 is the only Boeing jet airliner not to follow the company's "7x7" naming formula (excluding former McDonnell Douglas airliners, such as the MD-80). Boeing announced its plans to develop a new version of the 707 in July 1957. It was developed from the 707-120 to provide for short- to medium-range flights from shorter runways. The model was originally designated 707-020 before being changed