1954 saw the first flight of the Boeing 707, the intercontinental passenger plane which radically changed the concept of air transportation. Air travel, which had previously been the privilege of wealthy people, now became available to everyone. The Boeing 707 was a truly revolutionary airplane, and it is not surprising that its great success encouraged its manufacturer to develop a version for short-haul & medium-haul transport. The first flight of the new machine, now known as the Boeing 720, took place in November 1959. The Boeing 720 differed very little visually from its predecessor, and only a careful examination could tell the difference between these machines. The fuselage of Boeing 720 was shorter by 2.45m, and the wing had a slightly bigger sweep and other mechanical changes. The lift to weight ratio was more favourable, which allowed simplification of diverse elements of the design and the saving of weight and fuel consumption. The Boeing 720 could carry 116 people - 38 in the first class salon and 78 in second class. For passenger comfort three kitchens and three toilets were provided. The plane had JT3C-7 engines of 5670 kgf thrust each.
On July 5, 1960 the first machine N7201U was delivered to United Airlines. The further history of this machine is interesting - it was later purchased by private owners who refurbished the airplane as a VIP transport. The most famous occupants of this plane were the rock groups Led Zeppelin and Deep Purple, and the pop stars Elton John and Sonny & Cher. In total 65 machines were produced of this variant, which was soon modified as the Boeing 720B with more powerful JT3D engines. 89 of the 720B were produced.
The Boeing 720B differed visually from its predecessor in the new shape of its engine nacelles, and also in the different arrangement of doors and emergency exits on the sides of the fuselage. One of its earliest and best-known operators was one of the oldest U.S. airlines, Pan American. The take-off weight of this advanced version was increased a little, however all other characteristics remained almost without change.
The Boeing 707's successor did not achieve the huge success which it had enjoyed. The airlines did buy the 720, but without special interest. A large number of machines was soon sold on by American owned airlines to other countries and to other continents. Some machines were in use until the early 1990's.
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- Boeing 720B N784PA, "Jet Clipper Panama", Pan Am Airways, late 1960th
Technical Specifications:
- Wingspan: 39.9 meter
- Length: 41.4 meter
- Height: 12.7 meter
- Empty weight: 51,203 kg
- Take-off weight: 106,140 kg
- Cruiser speed: 983 km/h
- Range: 6,820 km
- Passenger: 112/149/165
- Engines: 4 x Pratt&Whittney JT3D-1, 75,6kN
- Crew: 3 pers