The Boeing 707 is often cited as the aircraft type that made commercial jet aviation so popular around the world. Its long range allowed airlines to operate the type on long routes, such as transatlantic and transpacific services. Production of the Boeing 707 began in 1956 and ended in 1978, and multiple variants were produced during this time to suit the needs of different airlines and markets.
The Boeing 707-120 was the first variant to be produced by Boeing, and could seat up to 189 passengers. Although it was not the most popular aircraft to be sold in the Boeing 707 series, it was still quite a successful model because the technology which Boeing developed from this program was rather advanced. Several airlines, such as Pan American World Airways (Pan Am) and American Airlines, operated this aircraft on transatlantic routes, but its short range meant that a stop was often required. Its maximum take-off weight was 247,000 lb (112,000 kg).
The Boeing 707-138 was a variant of the -120, but with a shorter fuselage. “38” was the customer code for Qantas, which meant that all Boeing aircraft produced for Qantas bore the number “38” in its registration. This aircraft was used on transpacific routes, often with a stop in Fiji.
The Boeing 707-320 was the intercontinental, stretched version of the -120. Its extended range was enabled by longer wings, which stored more fuel. Similar to the original -120, it also seated 189 passengers in a two class configuration. Its maximum take-off weight was also increased to 302,000 lb to allow airlines to operate it on transoceanic services.
The Boeing 707-320B was a variant of the -320. Notable modifications included adding a second inboard kink on the wings, as well as using curved low-drag wingtips instead of the earlier blunt ones. These changes improved the aerodynamics of the aircraft, and increased the maximum take-off weight to 328,000 lb. These adjustments made this aircraft popular among American carriers, such as Pan Am (85 aircraft) and American Airlines (10 aircraft). Altogether, Boeing produced 174 707-320B aircraft, making it the second most popular variant ever produced.
The Boeing 707-320C was the most popular of all the variants, with 337 produced by Boeing. This was because it had a convertible passenger-freight configuration, which enabled airlines to operate the type of many routes. In addition, airlines hoped that the versatility of the aircraft would allow them to sell the aircraft for more. As a result, many airlines operated this aircraft, such as Northwest Airlines (30 aircraft), Pan Am (34 aircraft), American Airlines (34 aircraft) and more.
Boeing 707-020 (Boeing 720)
The Boeing 720 was a shorter version of the standard Boeing 707-020, and was produced to suit the needs of airlines that needed to fly to airports with shorter runways. The fuselage was shortened by 9 feet, which lowered the maximum takeoff weight and the maximum passenger capacity. 154 Boeing 707-020s were built, and this aircraft was then succeeded by the Boeing 727 program, which aimed to provide airlines with lower capacity aircraft.
The Boeing 707 was a revolutionary aircraft because it propelled the aviation industry into the jet age, where jet aircraft replaced turboprop aircraft, and longer routes became achievable. Boeing consistently come up with updated versions to fit the needs of its customers and the industry, which is why so many variants were produced.
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