Boeing 707 lb (57.8 kN) with water injection. Maximum takeoff weight was 247,000 lb and first flight was on December 20, 1957. Major orders were the launch order for 20 707-121 aircraft by Pan Am and an American Airlines order for 30 707-123 aircraft. The first revenue flight was on October 26, 1958; 56 were built, plus seven short-bodied −138s; the last −120 was delivered to Western in May 1960. The 707-138 was a −120 with a fuselage 10 ft shorter than the others, with 5 ft (three frames) removed ahead and behind the wing, giving increased range. Maximum takeoff weight was
Boeing 707 other air transport infrastructure. The advent of the 707 also led to the upgrading of air traffic control systems to prevent interference with military jet operations. As the 1960s drew to a close, the exponential growth in air travel led to the 707 being a victim of its own success. The 707 was now too small to handle the increased numbers of passengers on the routes for which it was designed. Stretching the fuselage was not a viable option because the installation of larger, more powerful engines would need a larger undercarriage, which was not feasible given the design's limited