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 Commercial Airplanes 61, would step down immediately and be replaced. Kevin G. McAllister was named president and CEO of Boeing Commercial Airplanes (BCA). For all models sold beginning with the Boeing 707 in 1957, except the 720, Boeing's naming system for commercial airliners has taken the form of 7X7 (X representing a number). All model designations from 707 through 787 have been assigned, leaving 797 as the only 7X7 model name not assigned to a product. For model numbers in the 707 to 777 range, the model number consists of an airplane's model number, for example 707 or 747, followed by a