Misplaced Pages

#504495

99-711: Aware of the competition from the Rolls-Royce Conway turbofan, Pratt & Whitney decided to develop the JT3D turbofan from the JT3C turbojet for later deliveries of the Boeing 707 and the Douglas DC-8, then nearing entry into service. A 2-stage fan replaced the first 3 stages of the 9-stage JT3C LP compressor. On the LP turbine, the second stage was enlarged and a third stage added. Unlike GE with

198-403: A "two spool" compressor arrangement. Earlier engines generally consisted of a series of compressor stages connected via a shaft to one or more turbine stages, with the burners between them arranged around the shaft. Although this arrangement is mechanically simple, it has the disadvantage of lowering the efficiency of the compressor. Compressor stages run at their maximum efficiency when spinning at

297-478: A 3,200 nmi (5,900 km; 3,700 mi) 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. 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. It

396-406: 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

495-467: A considerably higher bypass ratio than the Conway. Nevertheless, the Conway was successful on those aircraft, and was the first commercial aero engine to be awarded an operational period of up to 10,000 hours between major overhauls. Due to the Conway, B707-420 take-offs were the loudest by jetliners on airports and over communities until Concorde entered service. However, the Conway was revolutionary, being

594-414: 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 (19,000 lbf (85 kN) takeoff thrust) and

693-454: 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. 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. The 132 in (3,400 mm) wide fuselage of the Dash 80 was large enough for four-abreast (two-plus-two) seating like

792-412: A dominant airliner manufacturer with its 7x7 series . The initial, 145-foot-long (44 m) 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 (2.4 m). Powered by Pratt & Whitney JT4A turbojets,

891-450: A full-length fan cowl. Pratt & Whitney provided a kit whereby JT3Cs could be converted to the JT3D specification, and performance, during an overhaul. In 1959, important orders for the engine were the Boeing 707-120B and Boeing 720B when American Airlines ordered one 707 powered by JT3D turbofans and KLM ordered a JT3D-powered Douglas DC-8 . Earlier 707s and DC-8s had been powered by

990-484: A fuselage 55 feet (17 m) longer than the 707-320B, to 208.6 feet (63.6 m) 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. The 707-820 would have cost US$ 10,000,000. Like

1089-648: 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. 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

SECTION 10

#1732852479505

1188-463: A kink in the trailing edge to add area inboard. Takeoff weight was increased to 302,000 lb (137,000 kg) initially and to 312,000 lb (142,000 kg) 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

1287-436: 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. The 707-820 was a proposed intercontinental stretched variant of the 707-320B. This 412,000-pound MTOW (187,000 kg) variant

1386-501: A number of different bypass or turbofan engine designs as early as the 1930s while he and Hayne Constant were trying to get their axial-flow jet engines working at the Royal Aircraft Establishment . However, simpler turbojet designs were prioritized during World War II for their use in military applications. Priorities changed dramatically at the end of the war and in 1946 Rolls-Royce agreed that existing engines like

1485-413: A seven-stage low-pressure compressor, the first six stages made of aluminium and the last of titanium. Behind this was the nine-stage high-pressure compressor, the first seven stages of titanium and the last two of steel. The bypass housing duct was also made of titanium. The bypass duct started after the seventh stage. The combustion area consisted of ten cannular flame cans . The high-pressure compressor

1584-657: A small cross-section, which limited the amount of bypass the engine could use. It nevertheless required higher power to support a 230,000 pounds (100,000 kg) gross weight, so Rolls responded with the larger RCo.5 . The new engine was similar to the RCo.2 in most ways, differing in details. The low-pressure compressor now had six stages and the high-pressure nine, driven by two and one stage turbines respectively. The first RCo.5 ran in July 1953 and passed an official type rating in August 1955 at 13,000 pounds-force (58,000 N). Construction of

1683-463: A specific speed for any given input air pressure - in a perfect compressor each stage would run at a separate speed. The multi-spool design, first used on the Bristol Olympus turbojet, is a compromise, the compressor being separated into "spools" designed to operate closer to most efficient speed, driven by separate turbines via concentric shafts. Two- and three-spool designs are common; beyond that

1782-650: A stronger structure to support a maximum takeoff weight increased by 19,000 lb (8,600 kg), 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

1881-588: A takeoff weight of 335,000 lb (152,000 kg). 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. 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. The 707-700

1980-580: A threat to the 757 and 767 programs. 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

2079-408: 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

SECTION 20

#1732852479505

2178-517: 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

2277-485: 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 wing quadjet with podded engines . Its larger fuselage cross-section allowed six-abreast economy seating, retained in

2376-558: Is publicized as being half the cost of the competing powerplant, the CFM International CFM56 , and is 40 dB quieter than the original JT3D engines. The first commercial orders for the 707 came on October 13, 1955, 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

2475-630: Is the only model remaining in United States Air Force service. It is expected to remain as a mainstay of the Air Force heavy bomber fleet until at least 2040, with options for replacing the 8 TF33 engines with more modern equivalents being considered. In April 2020, the USAF released a request for proposals for 608 commercial replacement engines, with the plan to award the contract in May 2021. In September 2021,

2574-480: The 1973 oil crisis . 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. Trans World Airlines flew

2673-456: 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. 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

2772-569: The Armstrong Siddeley Sapphire used by earlier models. For this role, Rolls-Royce designed an even larger model, the RCo.8 of 14,500 pounds-force (64,000 N), which ran for the first time in January 1956. However the RCo.8 was skipped over after receiving a request from Trans-Canada Airlines (TCA) to explore a Conway-powered Boeing 707 or Douglas DC-8 , having interested both companies in

2871-565: The Rolls-Royce Avon were advanced enough to enable a start to work on more advanced concepts like bypass. Griffith, who by then had become Chief Engineer at Rolls-Royce , suggested building a purely experimental bypass design using parts of the Avon and another experimental jet engine, the AJ.25 Tweed . In April 1947, a 5,000-pound-force (22,000 N) design was proposed, but over the next few months it

2970-555: The V bomber force to be supported in the field through air supply only. Vickers also planned on developing a passenger version of the same basic design as the VC-7. The V-1000 design looked like an enlarged de Havilland Comet but from the Valiant it took the wing layout and added a compound sweep (a passing vogue in UK design). It also featured the Comet's wing-embedded engines, demanding an engine with

3069-441: The "20" part of the designation is Boeing's "customer number" for its development aircraft. 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

Pratt & Whitney JT3D - Misplaced Pages Continue

3168-404: The -320 by adding a second inboard kink, a dog-toothed leading edge, and curved low-drag wingtips instead of the earlier blunt ones. These wingtips increased overall wingspan by 3.0 ft (0.9 m). Takeoff gross weight was increased to 328,000 lb (149,000 kg). The 175 707-320B aircraft were all new-build; no original -320 models were converted to fan engines in civilian use. First service

3267-409: The -320, but fitted with Rolls-Royce Conway 508 (RCo.12) turbofans (or by-pass turbojets as Rolls-Royce called them) of 18,000 lbf (80 kN) thrust each. 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

3366-513: 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

3465-432: The 21st century than 707s. 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. However, engineers discovered that

3564-399: The 707 also led to the upgrading of air traffic control systems to prevent interference with military jet operations. 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

3663-461: 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

3762-425: The 707's width again to compete, this time to 148 in (3,760 mm). The first flight of the first-production 707-120 took place on December 20, 1957, and FAA certification followed on September 18, 1958. 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. A number of changes were incorporated into

3861-501: 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 2,800 nmi (5,200 km; 3,200 mi) 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

3960-472: 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] (6,700 km; 4,100 mi), and could accommodate 174 in one class. With 141 passengers in two classes,

4059-648: The 707-320/420 could fly 3,750 nmi (6,940 km; 4,320 mi) and the 707-320B up to 5,000 nmi (9,300 km; 5,800 mi). 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. During and after World War II, Boeing

Pratt & Whitney JT3D - Misplaced Pages Continue

4158-501: 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

4257-568: The Boeing 707. After suspending its scheduled passenger service in April 2013, Saha continued to operate a small fleet of 707s on behalf of the Iranian Air Force . As of 2019, only a handful of 707s remain in operation, acting as military aircraft for aerial refueling, transport, and AWACS missions. 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

4356-503: The CJ805-23, Pratt & Whitney had not undertaken any transonic fan research prior to designing the JT3D, so they were unable to incorporate a single stage unit into the specification. Instead P&W designed a 2-stage unit based on some research they had done to support the J91 nuclear turbojet. On the Boeing 707 the JT3D fan nacelle was relatively short, whereas the Douglas DC-8 installation had

4455-577: The Conway-powered 707-420 was ordered by BOAC , Lufthansa , Varig , El Al and Air India . RCo.10's development was so smooth that after delivering a small number for testing, production deliveries switched to the 17,500-pound-force (78,000 N) RCo.12 , which was designed, built and tested before the airframes finished testing. Boeing's 707-420 featured a distinctive, scalloped exhaust nozzle (pictured above) incorporating noise suppression and mechanical and aerodynamic thrust reversal up to 50%, which

4554-460: The DC-8, such as United , Delta , and Eastern , were left without jets until September and lost market share on transcontinental flights. Qantas was the first non-US airline to use the 707s, starting in 1959. 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

4653-494: The JT3C and JT4A turbojets, and the improved efficiency of the turbofan soon attracted the airlines. A JT3D-powered 707-123B and 720-023B (the suffix B was to indicate a turbofan-powered aircraft) entered service with American Airlines on the same day, March 12, 1961. The Boeing KC-135 Stratotankers were all originally powered by turbojet engines. With the demise of many airline 707s, the United States Air Force took

4752-453: The JT3D, while 354 were fitted with CFM International CFM56 engines, which provide greater thrust, lower fuel consumption, and increased operational flexibility due to their lower noise footprint. The noise of the JT3D is one of the reasons NATO has debated re-fitting their E-3 Sentry AWACS fleet, since the aircraft are subject to restrictions that aircraft with modern engines are not. Operational flexibility would be further increased due to

4851-542: 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 144 in (3,660 mm) to allow five-abreast seating and use of the KC-135's tooling. Douglas Aircraft had launched its DC-8 with a fuselage width of 147 in (3,730 mm). The airlines liked the extra space and six-abreast seating, so Boeing increased

4950-563: The USAF announced that the TF33 would be replaced by the Rolls-Royce F130 . TF33-PW-102/A TF33-PW-103 Data from Aircraft engines of the World 1966/67 Related development Comparable engines Related lists Rolls-Royce Conway The Rolls-Royce RB.80 Conway was the first turbofan jet engine to enter service. Development started at Rolls-Royce in the 1940s, but

5049-542: The ability of higher power engines to increase the ceiling of the aircraft, extending the horizon for radar surveillance; for instance, RAF , French and Saudi E-3s routinely fly higher than NATO/USAF counterparts. In 1961, the TF33-powered Boeing B-52H Stratofortress entered service. The "H" model of the B-52 was the only production variant of the heavy bomber to be fitted with turbofan engines, and

SECTION 50

#1732852479505

5148-423: 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 40 in (100 cm) to the vertical stabilizer, applying full instead of partial rudder boost, and fitting an underfin to prevent over-rotation. These modifications except to

5247-586: The aircraft to be lost in a crash the following year . The RCo.11 was flown in the Victor on 20 February 1959. Boeing calculated that the Conway with a bypass of only 30% would increase the proposed 707-420's range by 8% above the otherwise identical 707-320 powered by Pratt & Whitney JT4A (J75) turbojets. That estimate proved optimistic; the actual range improvement was a maximum of 2%. In May 1956, TCA ordered Conway-powered DC-8-40s, followed by additional orders from Alitalia and Canadian Pacific Air Lines , while

5346-444: 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 15,800 lbf (70.3 kN) each (most eventually got 17,500 lbf (77.8 kN) 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

5445-416: The cockpit feeling ill. Johnston disconnected the faulty autopilot and manually stabilized the plane "with two slight control movements". 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 . The initial 145-foot-long (44 m) 707-120

5544-448: 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" quadjet prototype aircraft. Less than two years elapsed from project launch in 1952 to rollout on May 14, 1954, with

5643-630: 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 name "Conway" is the English spelling of the River Conwy , in Wales , in keeping with Rolls' use of river names for gas turbine engines. Alan Arnold Griffith had proposed

5742-466: 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

5841-478: The first Dash 80 flying on July 15, 1954. The prototype was a proof-of-concept aircraft for both military and civilian use. 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

5940-499: The first turbofan, and the first commercial engine, equipped with internally air-cooled turbine blades, which partially accounted for its high efficiency and an extremely high exhaust temperature of 1,247 °F (675 °C). Final development of the Conway first involved the RCo.42 , designed specifically for the Vickers VC10 . As the need for wing-embedded engines was long abandoned by this point, Rolls-Royce dramatically increased

6039-456: The idea. Rolls-Royce responded by designing an even larger model of the Conway, the 16,500 pounds-force (73,000 N) RCo.10 and offering the similar military-rated RCo.11 for the Victor. The new engine differed from the RCo.8 in having a new "zeroth stage" at the front of the low-pressure compressor, further increasing cold airflow around the engine. The RCo.10 first flew in the modified prototype Avro Vulcan VX770 on 9 August 1957 only for

SECTION 60

#1732852479505

6138-408: The initial 707's wing to help increase range and payload, giving birth to the 707-320. Pan Am inaugurated 707 service with a christening at National Airport on October 17, 1958, attended by President Eisenhower , followed by a transatlantic flight for VIPs (personal guests of founder Juan Trippe ) from Baltimore's Friendship International Airport to Paris. The aircraft's first commercial flight

6237-412: The inlet to the Conway engine, together with those for commercial Avon and Spey installations, was the subject of a patent infringement claim against Rolls-Royce by Rateau, a French manufacturer of steam turbines and automobile superchargers . Société pour l’exploitation des appareils Rateau of La Courneuve , who alleged the inlets infringed two of their expired 1939 patents. The patent stated that

6336-504: The intake, by its diffusing internal shape, determines the speed of the air entering the engine compressor. Since the Conway in the Boeing 707, and the other Rolls-Royce engines, had diffusing intakes, Rateau expected to be compensated for every engine made, as well as stopping all future production. Although Rateau's claim was only against Rolls-Royce, its understanding of the purpose of an intake applied to any jet engine installation. Witnesses for Rolls-Royce, including Frank Whittle, convinced

6435-452: The jets would bear 700-series numbers, and the first would be the 707. The marketing personnel at Boeing chose 707 because they thought it was more appealing than 700. The project was enabled by the Pratt & Whitney JT3C turbojet 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

6534-422: The judge that an intake did not produce the effect claimed and that the claim was "speculative" because, by 1939, no axial-flow aircraft jet engine had been built and that earlier patents from Frank Whittle and others had already considered the design of the intakes. Data from Jane's All The World's Aircraft 1969-70 Comparable engines Related lists Boeing 707#707-420 The Boeing 707

6633-622: The last new-build 707 airframes built as E-3 and E-6 aircraft. 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

6732-428: The last scheduled 707 flight for passengers by a US carrier on October 30, 1983, 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

6831-479: 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 . 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

6930-531: The later JT3D-3 version giving 18,000 lbf (80 kN). (This thrust did not require water injection, eliminating both the system and 5000–6000 lb 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,

7029-413: 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; 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 10 ft (3.0 m) shorter than the others, with 5 ft (1.5 m) (three frames) removed ahead and behind

7128-530: The low-level Valiant Pathfinder had been abandoned and so the first example was also destined to be the last. Nevertheless, it proved the basic concept sound and "ran perfectly for the whole of its 133 hours life." The work on the RCo.2 was soon put to good use. In October 1952, the Royal Air Force awarded a contract for the Vickers V-1000 , a large jet-powered strategic transport that was intended to allow

7227-404: The maximum takeoff weight the same as that of the -120 (247,000 lb (112 t)), the -138 was able to fly the longer routes that Qantas needed. Braniff International Airways ordered the higher-thrust version with Pratt & Whitney JT4 A 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

7326-486: The mechanical complexity is too great. The new version had a four-stage low-pressure compressor driven by a two-stage turbine and an eight stage high-pressure compressor driven by another two-stage turbine. Now known by the Ministry of Supply designation as the RCo.2 , design work was completed in January 1950 and the first example ran for the first time in July 1952 at 10,000 pounds-force (44,000 N) thrust. By this time,

7425-462: The new jet service StarStream , launching its first jet service, between New York-Idlewild International Airport and San Francisco International Airport , on January 25, 1959. American Airlines was the first domestic airline to fly its own jets, on January 25, 1959. TWA started domestic 707-131 flights in March and Continental Airlines started 707-124 flights in June; airlines that had ordered only

7524-588: The opportunity to buy the surplus airframes and use the engines to re-fit the KC-135As used by the Air National Guard and reserve squadrons with the civilian JT3D (designated TF33-PW-102). Over 150 aircraft were modified and the former KC-135A was re-designated the KC-135E. After long service for both airlines and air forces, the number of JT3D-powered aircraft is steadily decreasing. One hundred thirty five KC-135s use

7623-411: 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. Pratt & Whitney, in

7722-403: 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. 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

7821-528: The prototype V-1000 was well underway at Vickers Armstrong's Wisley works in the summer of 1955 when the entire project was cancelled. Having second thoughts about the concept of basing the V-bombers away from the UK, the need for the V-1000 became questionable and it became an easy decision to drop the project. The Conway was saved once again when it was selected to power the Handley Page Victor B.2 variant, replacing

7920-443: The tail dragging on the runway. 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 20 in (510 mm) apart, so this resulted in a shortening of 10 ft (3.0 m) to a length of 134 ft 6 in (41.0 m). With

8019-427: 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). 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 258,000 lb (117,000 kg) for both the long- and short-bodied versions. The 707-220

8118-413: The time preferred the more established Douglas Aircraft as a maker of passenger aircraft, 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

8217-402: 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, with

8316-414: The wing (from 138 ft 10 in (42.32 m) to 145 ft 6 in (44.35 m) ), with extensions to the fin and horizontal stabilizer extending the aircraft's length further. The longer wing carried more fuel, increasing range by 1,600 miles (2,600 km) and allowing the aircraft to operate as true transoceanic aircraft. The wing modifications included outboard and inboard inserts, as well as

8415-768: The wing, giving increased range. Maximum takeoff weight was the same 247,000 lb (112,000 kg) 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). 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 17,000 lbf (75.6 kN), with

8514-499: 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. In his autobiography, test pilot Tex Johnston describes

8613-501: The zero-stage diameter to increase the bypass from about 30% to 60%. Other major revisions were incorporated, primarily in the low-pressure compressor. First run was in March 1961. Takeoff rating was 20,370 pounds-force (90,600 N). For the Super VC10, the last model was the RCo.43 , rated at 21,800 pounds-force (97,000 N). The RCo.12 Conway was an axial-flow turbofan with a low bypass of about 30% or bypass ratio of 0.3:1. It had

8712-484: 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 335,000 lb (152,000 kg) MTOW. These were often identified as 707-320BA-H. The 707-320C has

8811-488: 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

8910-452: Was designed for hot and high operations with more powerful 15,800 lbf (70.3 kN) 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

9009-459: 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 13,000 lbf (57.8 kN) with water injection . Maximum takeoff weight was 247,000 lb (112,000 kg) and first flight was on December 20, 1957. Major orders were

9108-405: Was developed and supplied by Rolls-Royce. Douglas developed the DC-8's reverser-suppressor nozzle to work in conjunction with a variable ejector, which provided necessary, additional noise suppression. Although successful in this role, only 37 707s and 32 DC-8s were fitted with the Conway, due largely to delivery of the Pratt & Whitney JT3D : this was the first US-built bypass engine and had

9207-558: Was driven by a single-stage turbine using hollow air-cooled blades, which was followed by the two-stage turbine powering the low-pressure compressor. Accessories were arranged around the front of the engine to minimise overall diameter. The RCo.12 produced 17,500 pounds-force (78,000 N) for takeoff, weighed 4,544 pounds (2,061 kg) dry and had a specific fuel consumption of 0.725 at takeoff and 0.874 for typical cruise. In 1968, Hyfil carbon-fibre fan blades were installed on Conways of VC10s operated by BOAC . In November, 1966,

9306-464: Was from Idlewild Airport , New York, to Le Bourget , Paris, on October 26, 1958, with a fuel stop in Gander, Newfoundland . In December, National Airlines operated the first US domestic jet airline flights between New York/Idlewild and Miami, using 707s leased from Pan Am. In February 1956, rival global giant Trans World Airlines' then-President Howard Hughes ordered eight new Boeing 707-120, dubbing

9405-486: 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,

9504-560: Was modified to evolve into a larger 9,250-pound-force (41,100 N) design in response to a need for a new engine to power the Mk.2 low-level version of the Vickers Valiant bomber. The go-ahead to start construction of this larger design was given in October, under the name RB.80 . During development it was decided to further improve the basic design by adding another feature then becoming common,

9603-482: 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. 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

9702-543: 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 . The 707 uses engine-driven turbocompressors to supply compressed air for cabin pressurization . On many commercial 707s,

9801-582: Was to be powered by four 22,500-pound-force thrust (100 kN) Pratt & Whitney JT3D-15 turbofan engines, and it would have had a nearly 10-foot (3.0 m) extension in wingspan, to 155.5 feet (47.4 m). 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 (14 m) longer than the 707-320B, for a total length of 198.6 feet (60.5 m). This model would have carried 209 passengers in mixed-class configuration and 260 passengers in all-economy configuration. The 506 model would have had

#504495