Boeing 707

The Boeing 707 is a narrow-body, long-range, jet airliner created by Boeing in the late 1950s. Serially produced from 1958 to 1979. First Boeing commercial jet.

History

By the end of World War II, Boeing was one of the largest developers and manufacturers of heavy military aircraft in the world, primarily the B-17 Flying Fortress and B-29 Superfortress bombers. Later, with the beginning of the jet era, the same company created a new generation of strategic bombers B-47 Stratojet and B-52 Stratofortress. However, in the field of civil aviation, Boeing lagged significantly behind competitors, both American and foreign. By and large, commercial aviation was represented by the Boeing 314 Clipper hydroplane and the large 307 Stratoliner and 377 Stratocruiser piston planes, which no longer met the requirements of the time.

In the late 1940s, Boeing sent serious resources to research in the field of jet aviation, as the most promising, both in the military and in the civilian sphere. One of the catalysts for the work was a large order by the US Air Force to create promising tankers. The military had more than 800 KC-97 Stratofreighter tankers, but slow, piston planes had difficulty refueling faster jet aircraft.

Boeing studied various options for the structure of the airframe and, in the end, settled on the manufacture of prototype 367-80. The creation of this aircraft took only 2 years from 1952 to 1954. This was partly because a fairly large part of the work had already been done a little earlier when creating the B-52 bomber and the new aircraft inherited some of the developments on it. The 367-80 received 4 Pratt & Whitney JT3C engines – again, unified with B-52 engines. Such a unification was very helpful, given that it was a prototype tanker for the Air Force, which soon received the name KC-135 Stratotanker. An interesting fact: during one of the demonstration flights in 1955, the pilot Tex Johnston made an aerobatics figure on it – a barrel. A barrel … on an 80-ton, four-engine aircraft – one of the largest in the world at that time.

The company had doubts about the creation of passenger modification for a long time. Boeing was, almost entirely, a military manufacturer. Their extreme passenger Boeing 377 Statocruiser brought nothing but loss. However, marketing research and competition with Douglas with their DC-8s nevertheless led to the conclusion that the aircraft was needed, although it had to be modified to increase the fuselage diameter (from 3.35 m to 3.76 m).

Finally, on December 20, 1957, the Boeing 707-120 prototype made its first flight. The aircraft was certified fairly quickly – by the fall of 1958, he had received the right to go on flights. The design during testing underwent minimal modifications, concerning mainly the mechanization of the wing.

Nevertheless, when putting the aircraft into operation, there were difficulties with the fact that most pilots had difficulty retraining for a jet plane, getting used to piloting piston engines. Most often this concerned the difficulties with spontaneous yaw and rocking of the aircraft in flight. Boeing faced this problem even when creating bombers, but civilian pilots did not immediately learn how to effectively use previously unfamiliar means of adjusting flight. Once, the pilots completely turned off the new system, considering it redundant, which, in the end, led to the loss of flight stability and disaster. Another similar incident also nearly ended in an accident, when during a commercial flight the aircraft began to swing strongly. The situation was saved by the fact that one of the Boeing test pilots was on board among the passengers. He quickly replaced the captain and regained control. However, over time, this problem was resolved and similar incidents ceased.

Features

Boeing 707 – a four-engine monoplane with a low wing low sweep.

The aircraft are equipped mainly with Pratt & Whitney JT3D jet engines and their modifications. The power plant is equipped with turbochargers to maintain pressure in the cabin. During operation, the aircraft were motorized several times until the installation of CFM International CFM56 engines, which are common on modern medium-sized commercial airliners.

The Boeing 707 was the world’s first serial civilian airliner with engines in individual nacelles and suspended on pylons under the wing.

The Boeing 707 is a narrow-body aircraft. Armchairs are arranged 6 in a row (3 + 3) in economy class and 4 in a row (2 + 2) in business class. At different times, layouts underwent changes depending on customer requirements. The aircraft can accommodate up to 194 passengers (Boeing 707-320, single-class layout).

Modifications

  • 707-020 – also bearing the Boeing 720 index. The aircraft was created directly based on the 367-80 model. Starting customer – United Air Lines was an operator of DC-8 and chose not to buy its direct competitor – Boeing 707, so she bought modified 707 under the index 720. It is known that one of the Boeing 720 airliners was bought by a private company and received the name “The Starship”. Over the following years, it was actively used to transport celebrities, including rock bands Led Zeppelin, Deep Purple.
  • 707-120 – the first production version of the liner, equipped with a longer and wider fuselage. The aircraft was equipped with JT3C engines and could carry up to 189 passengers. The -120B version was later created with more efficient JT3D engines.
  • 707-220 – A modification created for operation in conditions of heat and highlands. Equipped with forced JT4A engines. A total of 5 aircraft were made, one of which was lost during flight tests. Its release was canceled after the creation of version 707-120B.
  • 707-320 – received the name Intercontinental and was extended by 2 meters version 707-120 with JT4A engines. The wing and tail were also increased, which, coupled with increased fuel tanks, increased flight range. The additional space in the cabin was used mainly to increase the comfort of passengers, and not to increase their number.
  • 707-420 – was identical to the -320 model, but equipped with Roll-Royce Conway 508 engines and had an increased tail unit (European aircraft controllers required the possibility of safe flight in the event of a single-engine failure). The aircraft was delivered to Lufthansa, some British airlines, as well as to India and Israel.
  • 707-320B – modification of the 320th model with improved airframe elements that increased aerodynamic quality. Take-off weight increased to 151 tons. Boeing released 175 airliners of this version and upgraded it to its level part of the already existing machines.
  • 707-320C – could convert from a passenger to a cargo version, which made it the most popular version of the 707th. The plane received a reinforced floor and a new cargo door. The wing mechanization was modernized, and JT3D engines were suspended under the wing. Initially, most of the aircraft were delivered in passenger versions capable, theoretically, to accommodate up to 219 passengers. However, over time, most of them were converted into freight.
  • 707-700 – test modification with installed CFM56 engines. The new engines made the aircraft much more economical, however, it still did not go into the series, losing its niche to the newest Boeing 757.

Even though the Boeing 707 has almost left the world of commercial transportation, it is still actively used in the military sphere.

  • E-3 Sentry is a special aircraft for Long-Range Radar Detection (AWACS) or Airborne Warning and Control System (AWACS). It is equipped with a rotating location station inside the fairing above the fuselage.
  • VC-137C – Air Force One is a former aircraft of the President of the United States. It was actively used until the beginning of the XXI century.
  • E-6 is an air command and control command and control post designed to control the US nuclear triad. It is equipped with CFM-56 engines and special communication systems.
  • E-8 JSTARS – aircraft radar reconnaissance and communication with the troops. The location station can record the location and movement of targets at a distance of up to 250 kilometers.
  • C-18 – military transport modification. It is actively used for the transportation of personnel.
  • EC-18B is an aircraft for monitoring and tracking air tests of various equipment. The aircraft is equipped with a large antenna, hidden under the ball fairing in the bow.

Operation

Initially, Being 707 was inferior in the market to its main competitor – Douglas DC-8, due to the better reputation of Douglas and the greater reliability of their offspring. But, over time, the Boeing 707 was refined and proved its superiority, and the company itself has established itself as a reliable manufacturer of civilian equipment.

The largest customers of the aircraft were Pan American (PanAm) and Trans World Airlines (TWA), followed by many other US and European airlines. Having received an effective long-haul airliner, air carriers significantly expanded the geography and intensity of flights. Aircraft were mass-produced from 1957 to 1979. The record was the period of the late 1960s when Boeing supplied about a hundred aircraft annually.

Also, two modified aircraft under the VC-137 code was used as the American Borotov No. 1. These aircraft were in exploitation until 2001, serving the entire galaxy of US leaders from Dwight Eisenhower to George W. Bush. The current livery, which became standard for Air Force One, was developed for the VC-137 under the administration of John F. Kennedy.

By the 1970s, the air transportation market had grown significantly, flight intensity and volumes reached such proportions that airlines needed more capacious long-haul liners. As a result, in most commercial areas, the Boeing 707 gave way to a new generation of the first wide-body aircraft, the main of which was the Boeing 747.

As a result, the Boeing 707 was quickly driven out of airline fleets and continued to operate only in Third World countries. Passenger flights to the USA ended in the early 1980s. Nevertheless, some military modifications, in particular, tankers and AWACS aircraft based on the Boeing 707, are still in operation. A total of 865 model 707 aircraft were delivered.

Specifications

Typepassenger aircraft
Modification707-120B707-320B707-320C
PowerplantPratt & Whitney JT3D-3Pratt & Whitney JT3D
Engine thrust4 X 8,15 tf4 X 7,95 tf4 X 8,67 tf
Maximum seats189 max
174 (1 class)
137 (2 classes)
189 max
189 (1 class)
141 (2 classes)
219 max
194 (1 class)
13 cargo containers
Practical ceiling11 890 m
Range6 700 km9 300 km5 400 km
Maximum take-off weight117 t151,5 t
Cruising speed977 km/h
Wingspan 39,88 m43,41 m44,42 m
Length44,22 m46,61 m
Height12,70 m12,83 m12,80 m
Graduated from Embry-Riddle Aviation University with a master's degree in aviation science. He began his career as an aviation researcher in local periodicals. Has a pilot license. Now are the author and developer of the Plane Worlds.