The Boeing 720 is the intermediate-range member of the Boeing jet transport family. Although a completely different design from the weight and structural strength standpoints, the 720 is similar to the 707-120 in external outline aerodynamic design and control systems, but with a shorter fuselage similar to a 717/KC-135A. This has made possible the use of 707 passenger cabin interiors, flight deck, systems components and most 707 interchangeable and replaceable parts and spares.
The most important aerodynamic change compared with the 707-120 is a refinement to the wing leading-edge, which increases the angle of sweepback and decreases the thickness/chord ratio, with improvement in take-off performance and cruising speed. These modifications were incorporated subsequently on the Boeing 707-120B.
Major weight saving has been achieved by lightening the structure to the extent made possible by reducing the standard fuel load. First ordered by United Airlines, only 154 Boeing 720s were built before production ceased in September 1967, the type being replaced by the Boeing 727.
Engines: 4 x P+W JT-3 D-1, 75.6kN
Wingspan: 39.9 m / 130 ft 11 in
Length: 41.5 m / 136 ft 2 in
Height: 11.7 m / 38 ft 5 in
Wing area: 226.0 sq.m / 2432.64 sq ft
Take-off weight: 103870 kg / 228995 lb
Empty weight: 49705 kg / 109581 lb
Cruise speed: 1000 km/h / 621 mph
Ceiling: 12800 m / 42000 ft
Range w/max.fuel: 8400 km / 5220 miles
Range w/max.payload: 6700 km / 4163 miles