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 redesign to the wing and gear structures. The 707-820 was also cancelled in 1966 in favor of the 747. The militaries of the US and other countries have used the civilian 707 aircraft in a variety of roles, and under different designations. (The 707 and U.S. Air Force's KC-135 were developed in parallel from the Boeing 367–80 prototype.) The Boeing E-3 Sentry is a US military airborne warning and control system (AWACS) aircraft based on the Boeing 707 that provides all-weather surveillance, command, control, and communications. The VC-137C variant of the Stratoliner was a special-purpose design meant to serve as