The Boeing 707 is an early American long-range narrow-body airliner, the first jetliner developed and produced by Boeing Commercial Airplanes. Developed from the Boeing 367-80 prototype first flown in 1954, the initial 707-120 first flew on December 20, 1957. Pan Am began regular 707 service on October 26, 1958. With versions produced until 1979, the 707 is a swept wingquadjet with podded engines. Its larger fuselage cross-section allowed six-abreast economy seating, retained in the later 720, 727, 737, and 757 models.
Although it was not the first commercial jetliner in service, the 707 was the first to be widespread, and is often credited with beginning the Jet Age.[5] It dominated passenger air-transport in the 1960s, and remained common through the 1970s, on domestic, transcontinental, and transatlantic flights, as well as cargo and military applications. It established Boeing as a dominant airliner manufacturer with its 7x7 series. The initial, 145-foot-long (44m)707-120 was powered by Pratt & Whitney JT3C turbojet engines. The shortened, long-range 707-138 and the more powerful 707-220 entered service in 1959. The longer-range, heavier 707-300/400 series has larger wings and is stretched slightly by 8 feet (2.4m). Powered by Pratt & Whitney JT4A turbojets, the 707-320 entered service in 1959, and the 707-420 with Rolls-Royce Conway turbofans in 1960.
The 720, a lighter short-range variant, was also introduced in 1960. Powered by Pratt & Whitney JT3D turbofans, the 707-120B debuted in 1961 and the 707-320B in 1962. The 707-120B typically flew 137 passengers in two classes over 3,600 nautical miles [nmi] (6,700km; 4,100mi), and could accommodate 174 in one class. With 141 passengers in two classes, the 707-320/420 could fly 3,750nmi (6,940km; 4,320mi) and the 707-320B up to 5,000nmi (9,300km; 5,800mi). The 707-320C convertible passenger-freighter model entered service in 1963, and passenger 707s have been converted to freighter configurations. Military derivatives include the E-3 Sentry airborne reconnaissance aircraft and the C-137 Stratoliner VIP transport. In total, 865 Boeing 707s were produced and delivered, not including 154 Boeing 720s.
The 707 was based on the 367-80 "Dash80"N708PA, the first Boeing 707 built. (1957)
During and after World War II, Boeing was known for its military aircraft. The company had produced innovative and important bombers, from the B-17 Flying Fortress and B-29 Superfortress to the jet-powered B-47 Stratojet and B-52 Stratofortress, but its commercial aircraft were not as successful as those from Douglas Aircraft and other competitors. As Douglas and Lockheed dominated the postwar air transport boom, the demand for Boeing's offering, the 377 Stratocruiser, quickly faded with only 56 examples sold and no new orders as the 1940s drew to a close. That venture had netted the company a $15 million loss.[6] During 1949 and 1950, Boeing embarked on studies for a new jet transport and saw advantages with a design aimed at both military and civilian markets. Aerial refueling was becoming a standard technique for military aircraft, with over 800 KC-97 Stratofreighters on order. The KC-97 was not ideally suited for operations with the USAF's new fleets of jet-powered fighters and bombers; this was where Boeing's new design would win military orders.[7]
As the first of a new generation of American passenger jets, Boeing wanted the aircraft's model number to emphasize the difference from its previous propeller-driven aircraft, which bore 300-series numbers. The 400-, 500- and 600-series were already used by their missiles and other products, so Boeing decided that the jets would bear 700-series numbers, and the first would be the 707.[8] The marketing personnel at Boeing chose 707 because they thought it was more appealing than 700.[9]
The project was enabled by the Pratt & Whitney JT3Cturbojet engine, the civilian version of the J57 that yielded much more power than the previous generation of jet engines and was proving itself with the B-52. Freed from the design constraints imposed by limitations of late-1940s jet engines, developing a robust, safe, and high-capacity jet aircraft was within reach for Boeing. Boeing studied numerous wing and engine layouts for its new transport/tanker, some of which were based on the B-47 and C-97, before settling on the 367-80 "Dash 80" quadjetprototype aircraft. Less than two years elapsed from project launch in 1952 to rollout on May 14, 1954, with the first Dash 80 flying on July 15, 1954.[10] The prototype was a proof-of-concept aircraft for both military and civilian use.[10] The United States Air Force was the first customer, using it as the basis for the KC-135 Stratotanker aerial refueling and cargo aircraft.
Whether the passenger 707 would be profitable was far from certain. At the time, nearly all of Boeing's revenue came from military contracts. In a demonstration flight over Lake Washington outside Seattle, on August 7, 1955, test pilot Tex Johnston performed a barrel roll in the 367-80 prototype.[11] Although he justified his unauthorized action to Bill Allen, then president of Boeing, as selling the airplane with a 1 'g' maneuver he was told not to do it again.[12]
The 132in (3,400mm) wide fuselage of the Dash 80 was large enough for four-abreast (two-plus-two) seating like the Stratocruiser. Answering customers' demands and under Douglas competition, Boeing soon realized this would not provide a viable payload, so it widened the fuselage to 144in (3,660mm) to allow five-abreast seating and use of the KC-135's tooling.[13] Douglas Aircraft had launched its DC-8 with a fuselage width of 147in (3,730mm). The airlines liked the extra space and six-abreast seating, so Boeing increased the 707's width again to compete, this time to 148in (3,760mm).[14]
Production and testing
Early 707-120 in Boeing livery. This aircraft, N709PA, would later crash in 1963 as Pan Am Flight 214.Boeing 707 six-abreast cabin
The first flight of the first-production 707-120 took place on December 20, 1957, and FAA certification followed on September 18, 1958.[15] Both test pilots Joseph John "Tym" Tymczyszyn and James R. Gannett were awarded the first Iven C. Kincheloe Award for the test flights that led to certification.[16] A number of changes were incorporated into the production models from the prototype. A Krueger flap was installed along the leading edge between the inner and outer engines on early 707-120 and -320 models.[17][18] This was in response to de Havilland Comet overrun accidents which occurred after over-rotating on take-off. Wing stall would also occur on the 707 with over-rotation so the leading-edge flaps were added to prevent stalling even with the tail dragging on the runway.[19]
Further developments
The -320 and -420 are 8 ft (2.4 m) longer than the initial -120; later 707s were powered by JT3D turbofans.
The initial standard model was the 707-120 with JT3C turbojet engines. Qantas ordered a shorter-bodied version called the 707-138, which was a -120 with six fuselage frames removed, three in front of the wings, and three aft. The frames in the 707 were set 20in (510mm) apart, so this resulted in a shortening of 10ft (3.0m) to a length of 134ft 6in (41.0m). With the maximum takeoff weight the same as that of the -120 (247,000lb (112t)), the -138 was able to fly the longer routes that Qantas needed.[18]Braniff International Airways ordered the higher-thrust version with Pratt & Whitney JT4A engines, the 707-220. The final major derivative was the 707-320, which featured an extended-span wing and JT4A engines, while the 707-420 was the same as the -320, but with Conway turbofan engines.
Though initially fitted with turbojet engines, the dominant engine for the Boeing 707 family was the Pratt & Whitney JT3D, a turbofan variant of the JT3C with lower fuel consumption and higher thrust. JT3D-engined 707s and 720s were denoted with a "B" suffix. While many 707-120Bs and -720Bs were conversions of existing JT3C-powered machines, 707-320Bs were available only as newly built aircraft, as they had a stronger structure to support a maximum takeoff weight increased by 19,000lb (8,600kg), along with modifications to the wing. The 707-320B series enabled nonstop westbound flights from Europe to the West Coast of the United States and from the US to Japan.
The final 707 variant was the 707-320C, (C for "Convertible"), which had a large fuselage door for cargo. It had a revised wing with three-sectioned leading-edge flaps, improving takeoff and landing performance and allowing the ventral fin to be removed (although the taller fin was retained). The 707-320Bs built after 1963 used the same wing as the -320C and were known as 707-320B Advanced aircraft.
In total, 1,010 707s were built for civilian use between 1958 and 1978, though many of these found their way to military service. The 707 production line remained open for purpose-built military variants until 1991,[20] with the last new-build 707 airframes built as E-3 and E-6 aircraft.[citation needed]
Traces of the 707 are still found in the 737, which uses a modified version of the 707's fuselage, as well as the same external nose and cockpit configurations as those of the 707. These were also used on the previous 727, while the 757 also used the 707 fuselage cross-section.
The 707's wings are swept back at 35°, and like all swept-wing aircraft, display an undesirable "Dutch roll" flying characteristic that manifests itself as an alternating combined yawing and rolling motion. Boeing already had considerable experience with this on the B-47 and B-52, and had developed the yaw damper system on the B-47 that would be applied to later swept-wing configurations like the 707. However, many pilots new to the 707 had no experience with this instability as they were mostly accustomed to flying straight-wing propeller-driven aircraft such as the Douglas DC-7 and Lockheed Constellation.
On one customer-acceptance flight, where the yaw damper was turned off to familiarize the new pilots with flying techniques, a trainee pilot's actions violently exacerbated the Dutch roll motion and caused three of the four engines to be torn from the wings. The plane, a brand new 707-227, N7071, destined for Braniff, crash-landed on a river bed north of Seattle at Arlington, Washington, killing four of the eight occupants.[21]
In his autobiography, test pilot Tex Johnston describes a Dutch roll incident he experienced as a passenger on an early commercial 707 flight. As the aircraft's movements did not cease and most of the passengers became ill, he suspected a misrigging of the directional autopilot (yaw damper). He went to the cockpit and found the crew unable to understand and resolve the situation. He introduced himself and relieved the ashen-faced captain who immediately left the cockpit feeling ill. Johnston disconnected the faulty autopilot and manually stabilized the plane "with two slight control movements".[22]
Johnston recommended Boeing increase the height of the tail fin, add a boosted rudder as well as add a ventral fin. These modifications were aimed at mitigating Dutch roll by providing more directional stability in yaw.[23]
The initial 145-foot-long (44m)707-120 was powered by Pratt & Whitney JT3C turbojet engines.
The JT3D-3B engines are readily identifiable by the large gray secondary-air inlet doors in the nose cowl. These doors are fully open (sucked in at the rear) during takeoff to provide additional air. The doors automatically close with increasing airspeed.
The 707 was the first commercial jet aircraft to be fitted with clamshell-type thrust reversers.[24]
Turbocompressors
The 707 uses engine-driven turbocompressors to supply compressed air for cabin pressurization. On many commercial 707s, the outer port (number 1) engine mount is distinctly different from the other three, as this engine is not fitted with a turbocompressor. Later-model 707s typically had this configuration, although American Airlines had turbocompressors on engines 2 and 3 only. Early 707 models often had turbocompressor fairings on all four engines, but with only two or three compressors installed.[25]
Upgraded engines
Omega Air's 707-330C testbed for the 707RE program takes off from the Mojave Airport, 2007
Pratt & Whitney, in a joint venture with Seven Q Seven (SQS) and Omega Air, selected the JT8D-219 low-bypass turbofan as a replacement powerplant for Boeing 707-based aircraft, calling their modified configuration a 707RE.[26] Northrop Grumman selected the -219 to re-engine the US Air Force's fleet of 19 E-8 Joint STARS aircraft, which would allow the J-STARS more time on station due to the engine's greater fuel efficiency. NATO also planned to re-engine their fleet of E-3 Sentry AWACS aircraft. The -219 is publicized as being half the cost of the competing powerplant, the CFM International CFM56, and is 40dB quieter than the original JT3D engines.[26]
Operational history
The first commercial orders for the 707 came on October 13, 1955,[27] when leading global carrier Pan Am committed to 20 Boeing 707s, and 25 Douglas DC-8s, dramatically increasing their passenger capacity (in available revenue passenger seat-miles per hour/per day) over its existing fleet of propeller aircraft. The competition between the 707 and DC-8 was fierce. Pan Am ordered these planes when and as they did so that they would be the operators of the "first-off" production line for each aircraft type. Once the initial batch of the aircraft had been delivered to them and put into operation, Pan Am would have the distinction of being not only the "Launch Customer" for both transcontinental American jets, but the exclusive operator of American intercontinental jet transports for at least a year.
The only rival in intercontinental jet aircraft production at the time was the British de Havilland Comet. However, the Comet series had been the subject of fatal accidents (due to design flaws) early in its introduction and withdrawn from service; virtually redesigned from scratch, it was still smaller and slower than the 707 when reintroduced as version -4. In addition, airlines and their passengers at the time preferred the more established Douglas Aircraft as a maker of passenger aircraft,[citation needed] and several major carriers committed only to the Douglas DC-8, delayed by Douglas' decision to wait for the larger and more fuel efficient (Pratt & Whitney JT4A) turbojet to design a larger and longer range aircraft around. Anticipating this advantage, Boeing made a late and costly decision to redesign and enlarge the initial 707's wing to help increase range and payload, giving birth to the 707-320.[28]
American Airlines was the first domestic airline to fly its own jets, on January 25, 1959.[citation needed] TWA started domestic 707-131 flights in March and Continental Airlines started 707-124 flights in June; airlines that had ordered only the DC-8, such as United, Delta, and Eastern, were left without jets until September and lost market share on transcontinental flights.[citation needed] Qantas was the first non-US airline to use the 707s, starting in 1959.[32][33]
The 707 quickly became the most popular jetliner of its time. Its success led to rapid developments in airport terminals, runways, airline catering, baggage handling, reservations systems, and other air transport infrastructure. The advent of the 707 also led to the upgrading of air traffic control systems to prevent interference with military jet operations.[34]
As the 1960s drew to a close, the exponential growth in air travel led to the 707 being a victim of its own success. The 707 had become too small to handle the increased numbers of passengers on the routes for which it had been designed. Stretching the fuselage again was not a viable option because the installation of larger, more powerful engines would need a larger undercarriage, which was not feasible given the design's limited ground clearance at takeoff. Boeing's answer to the problem was the first wide-body airliner—the Boeing 747. The 707's first-generation engine technology was also rapidly becoming obsolete in the areas of noise and fuel economy, especially after the 1973 oil crisis.[citation needed]
Iranian Saha Airlines was the last commercial operator, until April 2013
Operations of the 707 were threatened by the enactment of international noise regulations in 1985. Shannon Engineering of Seattle developed a hush kit with funding from Tracor, Inc, of Austin, Texas. By the late 1980s, 172 Boeing 707s had been equipped with the Quiet 707 package. Boeing acknowledged that more 707s were in service than before the hush kit was available.[35]
Trans World Airlines flew the last scheduled 707 flight for passengers by a US carrier on October 30, 1983,[36] although 707s remained in scheduled service by airlines from other nations for much longer. Middle East Airlines of Lebanon flew 707s and 720s in front-line passenger service until the end of the 1990s. Since LADE of Argentina removed its 707-320Bs from regular service in 2007, Saha Airlines of Iran was the last commercial operator of the Boeing 707.[2][37] After suspending its scheduled passenger service in April 2013,[1] Saha continued to operate a small fleet of 707s on behalf of the Iranian Air Force.[2][38]
As of 2019, only a handful of 707s remain in operation, acting as military aircraft for aerial refueling, transport, and AWACS missions.[39]
Although certified as Series 100s, 200s, 300s, etc., the different 707 variants are more commonly known as Series 120s, 220s, 320s, and so on, where the "20" part of the designation is Boeing's "customer number" for its development aircraft.
707-020
The 707-020 (720) is 9 ft (2.7 m) shorter than the 707-120.
Announced in July 1957 as a derivative for shorter flights from shorter runways, the 707-020 first flew on November 23, 1959. Its type certificate was issued on June 30, 1960, and it entered service with United Airlines on July 5, 1960. As a derivative, the 720 had low development costs, allowing profitability despite few sales.
Compared to the 707-120, it has a length reduced by 9 feet (2.7 m), a modified wing and a lightened airframe for a lower maximum takeoff weight. Powered by four Pratt & Whitney JT3C turbojets, the initial 720 could cover a 2,800nmi (5,200km; 3,200mi) range with 131 passengers in two classes. Powered by JT3D turbofans, the 720B first flew on October 6, 1960, and entered service in March 1961. It could seat 156 passengers in one class over a 3,200nmi (5,900km; 3,700mi) range. A total of 154 Boeing 720s and 720Bs were built until 1967. Some 720s were later converted to the 720B specification. The 720 was succeeded by the Boeing 727 trijet.
Boeing 707-120, the aircraft's first production variant
707-120
The 707-120 was the first production 707 variant, with a longer, wider fuselage, and greater wingspan than the Dash 80. The cabin had a full set of rectangular windows and could seat up to 189 passengers.[40] It was designed for transcontinental routes, and often required a refueling stop when flying across the North Atlantic. It had four Pratt & Whitney JT3C-6 turbojets, civilian versions of the military J57, initially producing 13,000lbf (57.8kN) with water injection. Maximum takeoff weight was 247,000lb (112,000kg) 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;[41] 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 10ft (3.0m) shorter than the others, with 5ft (1.5m) (three frames) removed ahead and behind the wing, giving increased range. Maximum takeoff weight was the same 247,000lb (112,000kg) as the standard version. It was a variant for Qantas, thus had its customer number 38. To allow for full-load takeoffs at the midflight refueling stop in Fiji, the wing's leading-edge slats were modified for increased lift, and the allowable temperature range for use of full takeoff power was increased by 10°F (5.5°C).[citation needed] Seven -138s were delivered to Qantas between June and September 1959, and they first carried passengers in July of that year.
The 707-120B had Pratt & Whitney JT3D-1 turbofan engines, which were quieter, more powerful, and more fuel-efficient, rated at 17,000lbf (75.6kN), with the later JT3D-3 version giving 18,000lbf (80kN). (This thrust did not require water injection, eliminating both the system and 5000–6000lb of water.) The -120B had the wing modifications introduced on the 720 and a longer tailplane; a total of 72 were built, 31 for American and 41 for TWA, plus six short-bodied -138Bs for Qantas. American had its 23 surviving -123s converted to -123Bs, but TWA did not convert its 15 -131s. The only other conversions were Pan Am's five surviving -121s and one surviving -139, the three aircraft delivered to the USAF as -153s and the seven short-bodied Qantas -138s (making 13 total 707s delivered to Qantas between 1959 and 1964).[citation needed] The first flight of the -120B was on June 22, 1960, and American carried the first passengers in March 1961; the last delivery was to American in April 1969. Maximum weight was 258,000lb (117,000kg) for both the long- and short-bodied versions.
707-220
The 707-220 was designed for hot and high operations with more powerful 15,800lbf (70.3kN) Pratt & Whitney JT4A-3 turbojets. Five of these were produced, but only four were ultimately delivered, with one being lost during a test flight. All were for Braniff International Airways and carried the model number 707-227; the first entered service in December 1959. This version was made obsolete by the arrival of the turbofan-powered 707-120B.
The 707-320 Intercontinental is a stretched version of the turbojet-powered 707-120, initially powered by JT4A-3 or JT4A-5 turbojets producing 15,800lbf (70.3kN) each (most eventually got 17,500lbf (77.8kN) JT4A-11s). The interior allowed up to 189 passengers, the same as the -120 and -220 series, but improved two-class capacity due to an 80-in fuselage stretch ahead of the wing (from 138ft 10in (42.32m) to 145ft 6in (44.35m) ), with extensions to the fin and horizontal stabilizer extending the aircraft's length further.[42] The longer wing carried more fuel, increasing range by 1,600 miles (2,600km) and allowing the aircraft to operate as true transoceanic aircraft. The wing modifications included outboard and inboard inserts, as well as a kink in the trailing edge to add area inboard.[18] Takeoff weight was increased to 302,000lb (137,000kg) initially and to 312,000lb (142,000kg) with the higher-rated JT4As and center section tanks. Its first flight was on January 11, 1958; 69 turbojet 707-320s were delivered through January 1963, the first passengers being carried (by Pan Am) in August 1959.
The 707-420 was identical to the -320, but fitted with Rolls-Royce Conway 508 (RCo.12) turbofans (or by-pass turbojets as Rolls-Royce called them) of 18,000lbf (80kN) thrust each.[43] The first announced customer was Lufthansa. BOAC's controversial order was announced six months later, but the British carrier got the first service-ready aircraft off the production line. The British Air Registration Board refused to give the aircraft a certificate of airworthiness, citing insufficient yaw control, excessive rudder forces, and the ability to over-rotate on takeoff, stalling the wing on the ground (a fault of the de Havilland Comet 1). Boeing responded by adding 40in (100cm) to the vertical stabilizer, applying full instead of partial rudder boost, and fitting an underfin to prevent over-rotation. These modifications except to the fin under the tail became standard on all 707 variants and were retrofitted to all earlier 707s. The 37 -420s were delivered to BOAC, Lufthansa, Air-India, El Al, and Varig through November 1963; Lufthansa was the first to carry passengers, in March 1960.
The 707-320B had the application of the JT3D turbofan to the Intercontinental, but with aerodynamic refinements. The wing was modified from the -320 by adding a second inboard kink, a dog-toothed leading edge, and curved low-drag wingtips instead of the earlier blunt ones.[18] These wingtips increased overall wingspan by 3.0ft (0.9 m). Takeoff gross weight was increased to 328,000lb (149,000kg). The 175 707-320B aircraft were all new-build; no original -320 models were converted to fan engines in civilian use. First service was June 1962, with Pan Am.
The 707-320B Advanced is an improved version of the -320B, adding the three-section leading-edge flaps already seen on the -320C. These reduced takeoff and landing speeds and altered the lift distribution of the wing, allowing the ventral fin found on earlier 707s to be removed. From 1965, -320Bs had the uprated -320C undercarriage allowing the same 335,000lb (152,000kg) MTOW. These were often identified as 707-320BA-H.
707-320C
The 707-320C, a convertible passenger–freight configuration
The 707-320C has a convertible passenger–freight configuration, which became the most widely produced variant of the 707. The 707-320C added a strengthened floor and a new cargo door to the -320B model. The wing was fitted with three-section leading-edge flaps which allowed the removal of the underfin. A total of 335 of this variant were built, including some with JT3D-7 engines (19,000lbf (85kN) takeoff thrust) and a takeoff weight of 335,000lb (152,000kg). Most -320Cs were delivered as passenger aircraft with airlines hoping the cargo door would increase second-hand values. The addition of two additional emergency exits, one on either side aft of the wing raised the maximum passenger limit to 219.[citation needed] Only a few aircraft were delivered as pure freighters. One of the final orders was by the Iranian Government for 14 707-3J9C aircraft capable of VIP transportation, communication, and in-flight refueling tasks.[44]
707-700
The 707-700 was a test aircraft used to study the feasibility of using CFM International CFM56 engines on a 707 airframe and possibly retrofitting existing aircraft with the engine. After testing in 1979, N707QT, the last commercial 707 airframe, was restored to 707-320C configuration and delivered to the Moroccan Air Force as a tanker aircraft via a "civilian" order. Boeing abandoned the retrofit program, since they felt it would be a threat to the 757 and 767 programs.[45][46] The information gathered from testing led to the eventual retrofitting of CFM56 engines to the USAF C-135/KC-135R models, and some military versions of the 707 also used the CFM56. The Douglas DC-8 "Super 70" series with CFM56 engines was developed and extended the DC-8's life in a stricter noise regulatory environment. As a result, significantly more DC-8s remained in service into the 21st century than 707s.[citation needed]
Undeveloped variants
The 707-620 was a proposed domestic range-stretched variant of the 707-320B. The 707-620 was to carry around 200 passengers while retaining several aspects of the 707-320B. It would have been delivered around 1968 and would have also been Boeing's answer to the stretched Douglas DC-8 Series 60. Had the 707-620 been built, it would have cost around US$8,000,000.[47] However, engineers discovered that a longer fuselage and wing meant a painstaking redesign of the wing and landing-gear structures. Rather than spend money on upgrading the 707, engineer Joe Sutter stated the company "decided spending money on the 707 wasn't worth it". The project was cancelled in 1966 in favor of the newer Boeing 747.[48]
The 707-820 was a proposed intercontinental stretched variant of the 707-320B. This 412,000-pound MTOW (187,000kg) variant was to be powered by four 22,500-pound-force thrust (100kN) Pratt & Whitney JT3D-15 turbofan engines, and it would have had a nearly 10-foot (3.0m) extension in wingspan, to 155.5 feet (47.4m). Two variations were proposed, the 707-820(505) model and the 707-820(506) model. The 505 model would have had a fuselage 45 feet (14m) longer than the 707-320B, for a total length of 198.6 feet (60.5m). This model would have carried 209 passengers in mixed-class configuration and 260 passengers in all-economy configuration. The 506 model would have had a fuselage 55 feet (17m) longer than the 707-320B, to 208.6 feet (63.6m) in length. This second model would have carried 225 passengers in mixed-class configuration and 279 passengers in all-economy configuration. Like the 707-620, the 707-820 was also set to compete with the stretched DC-8-60 Super Series models. The design was being pitched to American, TWA, BOAC, and Pan Am at the time of its proposal in early 1965.[49] The 707-820 would have cost US$10,000,000.[47] Like the 707-620, the 707-820 would have required a massive structural redesign to the wing and gear structures. The 707-820 was also cancelled in 1966 in favor of the 747.[48]
The militaries of the US and other countries have used the civilian 707 aircraft in a variety of roles, and under different designations. (The 707 and US Air Force's KC-135 were developed in parallel from the Boeing 367–80 prototype.)
The Boeing E-3 Sentry is a US military airborne warning and control system (AWACS) aircraft based on the Boeing 707 that provides all-weather surveillance, command, control, and communications.
The Northrop Grumman E-8 Joint STARS is an aircraft modified from the Boeing 707-300 series commercial airliner. The E-8 carries specialized radar, communications, operations and control subsystems. The most prominent external feature is the 40ft (12 m) canoe-shaped radome under the forward fuselage that houses the 24ft (7.3 m) APY-7 active electronically scanned array side looking airborne radar antenna.
The Canadian Forces also operated the Boeing 707 with the designation CC-137 Husky (707-347C) from 1971 to 1997.
Boeing 717 was the company designation for the C-135 Stratolifter and KC-135 Stratotanker derivatives of the 367-80. (The 717 designation was later reused in renaming the McDonnell Douglas MD-95 to Boeing 717 after the company merged with Boeing.)[50]
John Travolta's 707-138: a -120 shortened by 10ft (3.0m)
Boeing's customer codes used to identify specific options and livery specified by customers was started with the 707, and has been maintained through all Boeing's models. In essence the same system as used on the earlier Boeing 377, the code consisted of two digits affixed to the model number to identify the specific aircraft version. For example, Pan Am was assigned code "21". Thus, a 707-320B sold to Pan Am had the model number 707-321B. The number remained constant as further aircraft were purchased; thus, when Pan Am purchased the 747-100, it had the model number 747-121.
In the 1980s, the USAF acquired around 250 used 707s to provide replacement turbofan engines for the KC-135E Stratotanker program.[51]
The 707 is no longer operated by commercial airlines. American actor John Travolta owned an ex-Qantas 707-138B, with the registration N707JT. In May 2017, he donated the plane to the Historical Aircraft Restoration Society near Wollongong, Australia.[52] The plane is planned to be flown to Shellharbour Airport, where HARS is based, once repairs to ensure safe flying condition have been completed. The repairs were delayed several times since the 2017 announcement.[53]
As of January 2019, the 707 has been in 261 aviation occurrences and 174 hull-loss accidents with a total of 3,039 fatalities.[56][57][58] The deadliest incident involving the 707 was the Agadir air disaster which took place on August 3, 1975, with 188 fatalities.
On January 14, 2019, a Saha Airlines cargo flight crashed, killing 15 people and seriously injuring one more person.[59] It was the last civil 707 in operation.[60]
VH-XBA model 707-138B (number 29) is one of the first 707s exported, and the first civilian jet registered in Australia (to Qantas in 1959); it is on display at the Qantas Founders Outback Museum in Longreach, Queensland, Australia.[61]
OO-SJA model 707-329 (number 78), ex-Sabena, is the first jetliner registered in Belgium; forward fuselage, salvaged following an uncontained engine failure and emergency landing,[62] is on display at the Royal Military Museum Brussels.[63]
4X-JYW model 707-328 (msn. 173617, number 110), is a former Air France (F-BHSE) aircraft sold to the Israeli Air Force; it is on display at the Israeli Air Force Museum, Beersheba – Hatzerim (LLHB).[64]
N7515A model 707-123 (msn. 17642, number 41), posing as D-ABOF, a 707-430 formerly operated by Lufthansa has its nose section preserved at the Deutsches Museum in Munich.[66]<
CC-CCG model 707-330B (msn. 18642, number 233), an ex-Lufthansa and LAN Chile craft, is undergoing restoration at Santiago – Los Cerillos, Chile (ULC/SCTI) and will be repainted in the Chilean airline's 1960s scheme.[citation needed]
EP-IRJ model 707-321B (msn. 18958, number 475), a former Iran Air aircraft, was originally delivered to Pan Am as N416PA, and is currently the Air Restaurant at Mehrabad Airport, Tehran.[citation needed]
N893PA model 707-321B (msn. 20030, number 791), a former CAAC aircraft originally delivered to Pan Am, is preserved at Tianjin, China.[citation needed]
HZ-HM2 Model 707-386C (msn. 21081, number 903) is a Saudi Air Force VIP aircraft painted in the current Saudia color scheme; delivered in 1975, it is registered as HZ-HM1 and preserved at the Saudi Air Force Museum, Riyadh.[citation needed]
The Boeing 727 is an American narrow-body airliner that was developed and produced by Boeing Commercial Airplanes. After the heavier 707 quad-jet was introduced in 1958, Boeing addressed the demand for shorter flight lengths from smaller airports. On December 5, 1960, the 727 was launched with 40 orders each from United Airlines and Eastern Air Lines. The first 727-100 rolled out on November 27, 1962, first flew on February 9, 1963, and entered service with Eastern on February 1, 1964.
The Douglas DC-8 is an early long-range narrow-body jetliner designed and produced by the American Douglas Aircraft Company. Work began in 1952 towards the United States Air Force's (USAF) requirement for a jet-powered aerial refueling tanker. After losing the USAF's tanker competition to the rival Boeing KC-135 Stratotanker in May 1954, Douglas announced in June 1955 its derived jetliner project marketed to civil operators. In October 1955, Pan Am made the first order along with the competing Boeing 707, and many other airlines soon followed. The first DC-8 was rolled out in Long Beach Airport on April 9, 1958, and flew for the first time on May 30. Following Federal Aviation Administration (FAA) certification in August 1959, the DC-8 entered service with Delta Air Lines on September 18.
A jet airliner or jetliner is an airliner powered by jet engines. Airliners usually have two or four jet engines; three-engined designs were popular in the 1970s but are less common today. Airliners are commonly classified as either the large wide-body aircraft, medium narrow-body aircraft and smaller regional jet.
The Lockheed L-2000 was Lockheed Corporation's entry in a government-funded competition to build the United States' first supersonic airliner in the 1960s. The L-2000 lost the contract to the Boeing 2707, but that competing design was ultimately canceled for political, environmental and economic reasons.
The Pratt & Whitney JT8D is a low-bypass turbofan engine introduced by Pratt & Whitney in February 1963 with the inaugural flight of the Boeing 727. It was a modification of the Pratt & Whitney J52 turbojet engine which powered the US Navy A-6 Intruder and A-4 Skyhawk attack aircraft. Eight models comprise the JT8D standard engine family, covering the thrust range from 12,250 to 17,400 pounds-force, and power the 727, 737-100/200, and DC-9. The updated JT8D-200 family, covering the 18,900 to 21,000 pounds-force, powers the MD-80 and re-engined Super 27 aircraft. The JT8D was built under license in Sweden as the Volvo RM8, a redesigned afterburning derivative for the Saab 37 Viggen fighter. Pratt & Whitney also sells static versions for powerplant and ship propulsion as the FT8.
The Rolls-Royce RB.80 Conway was the first turbofan jet engine to enter service. Development started at Rolls-Royce in the 1940s, but the design was used only briefly, in the late 1950s and early 1960s, before other turbofan designs replaced it. The Conway engine was used on versions of the Handley Page Victor, Vickers VC10, Boeing 707-420 and Douglas DC-8-40.
The Pratt & Whitney JT3D is an early turbofan aircraft engine derived from the Pratt & Whitney JT3C. It was first run in 1958 and was first flown in 1959 under a B-45 Tornado test aircraft. Over 8,000 JT3Ds were produced between 1959 and 1985. Most JT3D engines still in service today are used on military aircraft, where the engine is referred to by its US military designation of TF33.
The Pratt & Whitney J57 is an axial-flow turbojet engine developed by Pratt & Whitney in the early 1950s. The J57 was the first 10,000 lbf (45 kN) thrust class engine in the United States. It is a two spool engine.
British Airtours was a charter airline in the United Kingdom with flight operations out of London Gatwick and Manchester Airports.
The Pratt & Whitney J75 is an axial-flow turbojet engine first flown in 1955. A two-spool design in the 17,000 lbf (76 kN) thrust class, the J75 was essentially the bigger brother of the Pratt & Whitney J57 (JT3C). It was known in civilian service as the JT4A, and in a variety of stationary roles as the GG4 and FT4.
The Shanghai Y-10 or Yun-10 is a four engined narrow-body jet airliner developed in the 1970s by the Shanghai Aircraft Research Institute. The plane used Boeing's 707-320C as reference, designed according to Federal Aviation Regulation.
The Boeing 367-80 is a retired American four-engined jet prototype aircraft built by Boeing to demonstrate the advantages of jet propulsion for commercial aviation. It served as basis for the design of the KC-135 tanker and the 707 airliner.
The Boeing CC-137 is a retired transport and tanker aircraft which served with the Canadian Forces from 1970 to 1997. The Boeing 707-347C aircraft provided long range passenger transport for the military, VIP transport for government and air-to-air refueling for fighters such as the CF-116 Freedom Fighter and CF-18 Hornet. It was replaced by the Airbus CC-150 Polaris in the transport role and much later in the tanker role.
The Boeing 747SP is a shortened version of the Boeing 747 wide-body airliner, designed for a longer range. It is the highest flying subsonic passenger airliner, with a service ceiling of 45,100 feet (13,700 m). Boeing needed a smaller aircraft to compete with the McDonnell Douglas DC-10 and Lockheed L-1011 TriStar tri-jet wide-bodies, introduced in 1971/1972. Pan Am requested a 747-100 derivative to fly between New York and the Middle East, a request also shared by Iran Air, and the first order came from Pan Am in 1973.
Pan Am Flight 816 was an international flight from Auckland, New Zealand, to San Francisco, California, via Tahiti, French Polynesia, and Los Angeles, California. It was operated by a Pan Am Boeing 707-321B bearing the registration N417PA and named Clipper Winged Racer. On July 22, 1973, at 10:06 P.M. local time, the Boeing 707 took off from Faa'a International Airport in Papeete. Thirty seconds after takeoff, the airliner, carrying 79 passengers and crew, crashed into the sea. All occupants except 1 passenger were killed.
The Boeing C-137 Stratoliner is a retired VIP transport aircraft derived from the Boeing 707 jet airliner used by the United States Air Force. Other nations also bought both new and used 707s for military service, primarily as VIP or tanker transports. In addition, the 707 served as the basis for several specialized versions, such as the E-3 Sentry AWACS aircraft. The designation C-18 covers several later variants based on the 707-320B/C series. The C-137 should not be confused with the similar Boeing C-135 Stratolifter; although they share a common ancestor the two aircraft have different fuselages, among other structural differences.
The Boeing 720 is an American narrow-body airliner produced by Boeing Commercial Airplanes. Announced in July 1957 as a 707 derivative for shorter flights from shorter runways, the 720 first flew on November 23, 1959. Its type certificate was issued on June 30, 1960, and it entered service with United Airlines on July 5, 1960. A total of 154 Boeing 720s and 720Bs were built until 1967. As a derivative, the 720 had low development costs, allowing profitability despite relatively few sales.
A four-engined jet, sometimes called a quadjet, is a jet aircraft powered by four engines. The presence of four engines offers increased power and redundancy, allowing such aircraft to be used as airliners, freighters, and military aircraft. Many of the first purpose-built jet airliners had four engines, among which stands the De Havilland Comet, the world's first commercial jetliner. In the decades following their introduction, their use has gradually declined due to a variety of factors, including the approval of twin-engine jets to fly farther from diversion airports as reliability increased, and an increased emphasis on fuel efficiency.
Pan Am Flight 799 was an international cargo flight from Los Angeles International Airport to Cam Ranh Airport in South Vietnam that crashed on December 26, 1968, near Anchorage, Alaska. The aircraft involved was a Boeing 707-321C aircraft operated by Pan American World Airways. All three crew members died in the crash.
On 13 October 1976, a Boeing 707-131F, a chartered cargo aircraft operated for Lloyd Aéreo Boliviano (LAB) crashed shortly after takeoff at El Trompillo Airport, Santa Cruz de la Sierra, Bolivia, into a residential neighbourhood. All three crew on board were killed, along with 88 other fatalities on the ground, bringing the total up to 91. It is the deadliest air disaster to happen on Bolivian soil.
References
Footnotes
↑ Retired from airline passenger use in April 2013;[1] civilian service ended in January 2019[2]
↑ Commercial aircraft were produced from 1956 to 1978. See C-137, E-3, E-6, and E-8 articles for production of military derivatives.
↑ Wilson, Stewart (1999). Airliners of the World. Fyshwick, Australia: Aerospace Publications. p.13. ISBN978-1-875671-44-1. The Boeing 707, the airliner which introduced jet travel on a large scale and p. 48. Quote: "The USA's first jetliner, the 707 was at the forefront of jet travel revolution..."
↑ Ruffin, Steven A (2005). Aviation's Most Wanted: The Top 10 book of Winged Wonders, Lucky Landings and Other Aerial Oddities. Washington D.C.: Potomac Books. p.320. ISBN978-1574886740.
↑ Cook, William H. Road to the 707: The Inside Story of Designing the 707. Bellevue, WA: TYC Publishing Company, 1991. ISBN978-0-9629605-0-5, p.249
↑ Glancey, Jonathan (October 19, 2014), "Boeing 707: The aircraft that changed the way we fly", BBC News, archived from the original on November 25, 2021, retrieved November 30, 2021, Boeing built 1,010 707s for commercial airlines between 1958 and 1978, and a further 800 for the military up until 1991
Bradley, Catherine (1983). Boeing 707 Super Profile. Yeovil, Somerset UK: Haynes Publishing. ISBN978-0-85429-356-8.
Lloyd, Alwyn T. Boeing 707 & AWACS in Detail and Scale. Falbrook, CA: Aero Publishers, 1987. ISBN978-0-8306-8533-2.
Cearley, George Walker. Boeing 707 & 720: A Pictorial History. Dallas: G.W. Cearley Jr, 1993. [ISBNmissing]
Smith, Paul Raymond. Boeing 707 – Airline Markings No. 3. Shrewsbury, Shropshire, UK: Swan Hill Press, 1993. ISBN978-1-85310-087-1.
Proctor, Jon. Boeing 720. Miami, FL: World Transport Press, 2001. ISBN978-1-892437-03-7.
Winchester, Jim (2002). Boeing 707. Shrewsbury, England: Airlife. ISBN978-1-84037-311-0.
Stachiw, Anthony L. and Andrew Tattersall. Boeing CC137 (Boeing 347C) in Canadian Service. St. Catherines, ON: Vanwell Publishing Ltd., 2004. ISBN978-1-55125-079-3.
Breffort, Dominique. Boeing 707, KC-135 and Civilian and Military Versions. Paris: Histoire & Collections, 2008. ISBN978-2-35250-075-9.
Kennedy, Charles (2018), Boeing 707 Manual, Sparkford, Yeovil, Somerset, UK: Haynes Publishing, ISBN978-1-78521-136-2 .
"Boeing 707 Revelations". Flight International. January 27, 1956. Archived from the original on May 20, 2013. Retrieved June 9, 2012.{{cite news}}: CS1 maint: bot: original URL status unknown (link)
"Boeing 707". Flight International. July 25, 1958. Archived from the original on March 7, 2017. Retrieved March 7, 2017.{{cite news}}: CS1 maint: bot: original URL status unknown (link)
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
