A trijet is a jet aircraft powered by three jet engines . In general, passenger airline trijets are considered to be second-generation jet airliners , due to their innovative engine locations, in addition to the advancement of turbofan technology. Trijets are more efficient than quadjets , but not as efficient as twinjets , which replaced trijets as larger and more reliable turbofan engines became available.
143-464: The McDonnell Douglas DC-10 is an American trijet wide-body aircraft manufactured by McDonnell Douglas . The DC-10 was intended to succeed the DC-8 for long- range flights. It first flew on August 29, 1970; it was introduced on August 5, 1971, by American Airlines . The trijet has two turbofans on underwing pylons and a third one at the base of the vertical stabilizer . The twin-aisle layout has
286-454: A T-tail configuration. The larger widebody Lockheed TriStar and DC-10/MD-11 mount an engine underneath each wing. Preliminary studies were done on the TriStar to reuse the fuselage and wing for a twinjet design though these never materialized due to Lockheed's lack of funds. Additionally in the late-1990s Boeing, which had taken over McDonnell Douglas, considered removing the tail engine from
429-423: A deadheading DC-10 flight instructor, performed a partially controlled emergency landing by constantly adjusting the thrust of the remaining two engines; 185 people on board survived, but 111 others died, and the aircraft was destroyed. The DC-10 was designed without backup flight controls because it was considered extremely improbable that all hydraulic systems would fail. However, due to their close proximity under
572-408: A high bypass turbofan , which produced 22,000 lbf (98.5 kN) of thrust. The conversions also includes new nacelles and pylons built by Grumman Aerospace . Maximum takeoff weights remained the same, but there was a slight reduction in payload because of the heavier engines. Modifications to create the -71 was more involved because the -61 did not have the improved wings and relocated engines of
715-628: A swept wing enabled a higher cruising speed and better range. First presented in 1950 as the Model 473-60C , Boeing failed to generate any interest from airlines, yet remained confident that the project was worthwhile and pressed ahead with a prototype, the Boeing 367-80 ("Dash-80"). After spending $ 16 million of its own money to build it, the Dash-80 rolled out on May 15, 1954. During mid-1952, Douglas opted to covertly begin work on definition studies for
858-540: A MTOW of 325,000 lb (147 t). It first flew on March 14, 1966, was certified on September 2, 1966, and entered service with United Airlines in February 1967. The long-range DC-8-62 followed in April 1967, stretched by 7 ft (2.1 m), could seat up to 189 passengers over 5,200 nautical miles [nmi] (9,600 km; 6,000 mi) with a larger wing for a MTOW up to 350,000 lb (159 t). The DC-8-63 had
1001-502: A commercial aircraft manufacturer, having received almost 300 orders for its piston-engine DC-6 and its successor, the DC-7, which had yet to fly. The Comet disasters, and the airlines' subsequent lack of interest in jets, seemed to validate the company's decision to remain with propeller -driven aircraft, but its inaction enabled rival manufacturers to take the lead instead. As early as 1949, rival company Boeing had started design work on
1144-486: A jet-powered transport aircraft. The company's design team examined various arrangements, including some that closely resembled the Comet. By mid-1953, the team had settled on a form similar to the final DC-8; an 80-seat, low-wing aircraft powered by four Pratt & Whitney JT3C turbojet engines, 30° wing sweep, and an internal cabin diameter of 11 feet (3.35 m) to allow five-abreast seating. The use of podded engines
1287-458: A large number of DC-8 early models being available, all used the same basic airframe, differing only in engines, weights and details; in contrast, the rival Boeing 707 range offered several fuselage lengths and two wingspans: the original 144-foot (44 m) 707-120, a 135-foot (41 m) version that sacrificed space to gain longer range, and the stretched 707-320, which at 153 feet (47 m) overall had 10 feet (3.0 m) more cabin space than
1430-451: A low overall accident rate as of 1998. The DC-10's initially poor safety record has continuously improved as design flaws were rectified and fleet hours increased. The DC-10's lifetime safety record is comparable to similar second-generation passenger jets as of 2008. The DC-10 has cargo doors that open outward; this allows the cargo area to be completely filled, as the doors do not occupy otherwise usable interior space when open. To overcome
1573-406: A maximum payload range of 4,604 miles (4,001 nmi; 7,409 km). The series 40 had a typical load range of 5,750 miles (5,000 nmi; 9,250 km) and a maximum payload range of 4,030 miles (3,500 nmi; 6,490 km). The DC-10 had two engine options and introduced longer-range variants a few years after entering service; these allowed it to distinguish itself from its main competitor,
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#17327647434371716-577: A new trijet called the MD-XX, which were lengthened versions of the MD-11 . The MD-XX Long Range aircraft would have been capable of traveling distances up to 8,320 nautical miles (15,410 km) and had a wingspan of 65 metres (213 ft). The project was canceled in 1996, one year before McDonnell Douglas was acquired by Boeing. Boeing ended production of the MD-11 after filling remaining customer orders since
1859-672: A new wing design and entered serial production from 1984 as the Tu-154M . With the exceptions of the Dassault Falcon 7X , Falcon 8x , and Falcon 900 business jets, no manufacturer currently produces three-engine airliners. Modern engines have extremely low failure rates and can generate much higher shaft power and thrust than early types. This makes twinjets more suitable than they were before for long-haul trans-oceanic operations, resulting in eased ETOPS restrictions; modern wide-body twin-engine jets usually have an ETOPS 180 or (in
2002-564: A new, twin-tail trijet design, whose tail engine appears to use a "straight" layout similar to the MD-11, but it is unknown if and when this will be developed or produced. However, the proposed Boeing X-48 blended wing body design, Lockheed's N+2 design study, and Aerion AS2 supersonic business jet were also supposed to have three engines. The AS2 programme was cancelled in May 2021 when Aerion Corporation shut down. Boom Technology 's planned Overture supersonic transport (SST) airliner
2145-817: A pure jet airliner. Boeing's military arm had experience with large long-range jets, such as the B-47 Stratojet and the B-52 Stratofortress strategic bombers. While producing and supporting these bombers for the United States Air Force (USAF), Boeing had developed a close relationship with the USAF's Strategic Air Command (SAC). The company also supplied the SAC's refueling aircraft, the piston-engined KC-97 Stratofreighters , but these proved to be too slow and low flying to easily work with
2288-536: A range of 3,800 miles (3,300 nmi; 6,100 km) with a typical passenger load and a range of 2,710 miles (2,350 nmi; 4,360 km) with maximum payload. Various models of the DC-10 promptly followed, such as the series 15, which had a typical load range of 4,350 miles (3,780 nmi; 7,000 km). The series 20 was powered by Pratt & Whitney JT9D turbofan engines, whereas the series 10 and 30 engines were General Electric CF6 . Prior to taking delivery of
2431-520: A rear center landing gear . It was to use Pratt & Whitney JT9D -15 turbofan engines, each producing 45,500 lbf (202 kN) of thrust, with a maximum takeoff weight of 530,000 pounds (240 t). However, engine improvements led to increased thrust and increased takeoff weight. Northwest Orient Airlines, one of the launch customers for this longer-range DC-10 requested the name change to DC-10-40. A proposed version with Rolls-Royce RB211 -524 engines for British Airways. The order never came and
2574-403: A result of aging, increasing operating costs and strict noise and emissions regulations, the number of active DC-8s continues to decline, with the youngest airframes passed a half-century of age as of 2024. For domestic use, powered by 13,500 lb (60.5 kN) Pratt & Whitney JT3C -6 turbojets with water injection. First Series 10 DC-8 flew on 30 May 1958. The initial DC-8-11 model had
2717-413: A seating configuration that exacerbated the effects of decompression, and as the cabin floor collapsed into the cargo bay, control cables were severed and the aircraft became uncontrollable. Investigators found that the DC-10's relief vents were not large enough to equalize the pressure between the passenger and cargo compartments during explosive decompression. Following this crash, a special subcommittee of
2860-460: A solely McDonnell Douglas product, but none proceeded beyond design studies. The KC-10 Extender is a military version of the DC-10-30CF for aerial refueling . The aircraft was ordered by the U.S. Air Force and delivered from 1981 to 1988. A total of 60 were built. These aircraft are powered exclusively by General Electric CF6 turbofan engines. The KDC-10 was an aerial refueling tanker for
3003-453: A succession of piston-engined aircraft ( DC-2 , DC-3 , DC-4 , DC-5 , DC-6 , and DC-7 ) through the 1930s, 1940s, and 1950s. While de Havilland flew the world's first jet airliner, the Comet , in May 1949, Douglas initially refrained from developing a jet airliner. De Havilland's pioneering Comet entered airline service in May 1952. Initially, it appeared to be a success, but the Comet
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#17327647434373146-475: A surge in demand for widebody airliners. However, the Boeing 747-400 , MD-11, Airbus A330 / A340 , and soon-to-be-built Boeing 777 were all behind schedule and couldn't fully meet the demand for widebody airliners. Production of first-generation widebodies like the Boeing 747-100 / 200 / 300 , L-1011, and DC-10 had already stopped, so the value of used DC-10-30s almost doubled, rising from less than $ 20 million to almost $ 40 million. The McDonnell Douglas DC-10
3289-707: A trijet aircraft) and Boeing worked on new widebody twinjet designs that would become the A330 and 777, respectively. The MD-11's long-range advantage was brief as it soon was threatened by the A330's four-engine derivative, the A340 , and the 777. The only other notable trijet development during the 1980s was in the Soviet Union , where the Tupolev Tu-154 was re-engined with the Soloviev D-30 engine as well as
3432-444: A typical seating for 270 in two classes. The initial DC-10-10 had a 3,500- nautical-mile [nmi] (6,500 km; 4,000 mi) range for transcontinental flights . The DC-10-15 had more powerful engines for hot and high airports. The DC-10-30 and –40 models (with a third main landing gear leg to support higher weights) each had intercontinental ranges of up to 5,200 nmi (9,600 km; 6,000 mi). The KC-10 Extender (based on
3575-538: A weight increase to 276,000 pounds (125,190 kg). 33 DC-8-20s were built plus 16 converted DC-8-10s. This model was originally named "DC-8B" but was renamed when the Series 30 was introduced. The first Series 20 DC-8 flew on 29 November 1958 and received FAA certification on 19 January 1960. For intercontinental routes, the three Series 30 variants combined JT4A engines with a one-third increase in fuel capacity and strengthened fuselage and landing gear. The DC-8-31
3718-419: A widebody aircraft smaller than the Boeing 747 yet capable of flying similar long-range routes from airports with shorter runways; this specification would be highly influential in the design of what would become the DC-10. It would become McDonnell Douglas's first commercial airliner after the merger between McDonnell Aircraft Corporation and Douglas Aircraft Company in 1967. An early DC-10 design proposal
3861-440: Is a trijet , being powered by three turbofan engines. Two of these engines are mounted on pylons that attach to the bottom of the wings, while the third engine is encased in a protective banjo-shaped structure that is mounted on the top of the rear fuselage. In comparison to the first generation of jetliners, these engines generated less noise and were usually smoke-free. The engines are equipped with thrust reversers which reduce
4004-452: Is a low-wing wide-body aircraft . It is sized to conduct medium to long-range flights, offering similar endurance to the larger Boeing 747 yet being able to use shorter runways and thus access airports that it could not. Dependent upon configuration, the main cabin can accommodate between 250 and 380 passengers across its main deck. The fuselage is split into two levels, the upper deck is the only one where passenger seating would be present as
4147-535: Is an upgrade to add a glass cockpit to the DC-10 with the re-designation to MD-10 . The upgrade included an Advanced Common Flightdeck similar to what was used on the MD-11 and was launched in September 1996. However, the actual avionics are shared with the Boeing 717 , using the Honeywell VIA liquid-crystal-displays. The program was continued by Boeing after its merger with McDonnell Douglas in 1997, and
4290-422: Is capable of performing all-weather operations, a function that many preceding jetliners had been incapable of. From the onset, it could perform takeoffs and landings completely under autopilot . Cassette tapes were used to load preprogrammed flight plans into the flight computer. As originally built, the cockpit was operated by a flight crew of three; numerous DC-10s have received a retrofitted glass cockpit and
4433-416: Is often less important than for scheduled-route operating airlines, trijets may still be of interest due to their immunity from ETOPS and the ability to take off from shorter runways and therefore have access to more airports. As a result, a sizeable number of trijets, such as the newly built Dassault Falcons , are in use by private operators and corporate flight departments. Airbus filed a patent in 2008 for
McDonnell Douglas DC-10 - Misplaced Pages Continue
4576-471: Is to replace the DC-8 with a more capable and fuel-efficient Boeing 777-200ER . The DC-8 was donated to Idaho State University and is preserved at Pocatello Regional Airport . As of October 2015 , the DC-8 had been involved in 146 incidents, including 84 hull-loss accidents , with 2,255 fatalities. The DC-8 has also been involved in 46 hijackings with 2 fatalities. The deadliest incident involving
4719-612: The 727 , Tu-154 , DC-10, and MD-11, have found second careers as cargo aircraft, as well as in limited charter, governmental, and military service. However, because of the average age of trijets and the COVID-19 pandemic , most non-private operators have chosen to retire quadjets and trijets and replace them with more efficient and cost-saving twinjets. Today, the only widely used trijet is the MD-11, mostly operated by UPS Airlines and FedEx Express in cargo service. For smaller private and corporate operators, where maximum fuel efficiency
4862-459: The 777 's General Electric GE90 . During the 1980s, McDonnell Douglas was the only Western manufacturer to continue development of the trijet design with an update to the DC-10 , the MD-11 , which initially held a range and payload advantage over its closest medium wide-body competitors which were twinjets, the in-production Boeing 767 and upcoming Airbus A330 . McDonnell Douglas had planned
5005-399: The Dassault Falcon 7X . The S-duct has low drag, and since the third engine is mounted closer to the centerline, the aircraft will normally be easy to handle in the event of an engine failure. However, S-duct designs are more complex and costlier, particularly for an airliner. Furthermore, the central engine bay would require structural changes in the event of a major re-engining (remodeling of
5148-573: The Dassault Falcon 900 are the only trijets still in production. One consideration with trijets is positioning the central engine. This is usually accomplished by placing the engine along the centerline, but still poses difficulties. The most common configuration is having the central engine located in the rear fuselage and supplied with air by an S-shaped duct ; this is used on the Hawker Siddeley Trident , Boeing 727 , Tupolev Tu-154 , Lockheed L-1011 TriStar , and, more recently,
5291-597: The General Electric CF6 , and the additional power from the third engine gave the DC-10/MD-11 advantages in longer range and/or heavier payload over the A300/A310/A330 twinjet. Since the 1990s, with further advancements in high-bypass turbofan technology, large twinjets have been equipped with purpose-designed engines such as the Boeing 777 's General Electric GE90 , allowing twinjets to perform
5434-528: The Hawker Siddeley Trident (1962) and the Boeing 727 (1963). Both were compromises to meet airline requirements; in the case of the Trident, it was to meet BEA's changing needs, while the 727 had to be acceptable for three different airlines. Although collaboration between the manufacturers was considered, it did not come about. Early American twinjet designs were limited by the FAA 's 60-minute rule , whereby
5577-526: The MD-10 with a glass cockpit that eliminated the need for a flight engineer . In February 2014, the DC-10 made its last commercial passenger flight. Cargo airlines continued to operate a small number as freighters . The Orbis Flying Eye Hospital is a DC-10 adapted for eye surgery . A few DC-10s have been converted for aerial firefighting use. Some DC-10s are on display, while other retired aircraft are in storage . Following an unsuccessful proposal for
5720-479: The Port Authority of New York and New Jersey expressed concern about the noise to be expected from the then still-unbuilt DC-8-61, and operators had to agree to operate it from New York at lower weights to reduce noise. By the early 1970s, legislation for aircraft noise standards was being introduced in many countries, and the 60 Series DC-8s were particularly at risk of being banned from major airports. In
5863-537: The Royal Netherlands Air Force . These were converted from civil airliners (DC-10-30CF) to a similar standard as the KC-10. Also, commercial refueling companies Omega Aerial Refueling Services and Global Airtanker Service operate three KDC-10 tankers for lease. The DC-10 Air Tanker is a DC-10-based firefighting tanker aircraft, using modified water tanks from Erickson Air-Crane . The MD-10
McDonnell Douglas DC-10 - Misplaced Pages Continue
6006-427: The United States Air Force 's CX-HLS (Heavy Logistics System) in 1965, Douglas Aircraft began design studies based on its CX-HLS submission. The aviation author John H. Fielder notes that the company was under competitive pressure to produce a widebody aircraft, having been somewhat slow in the previous decade to introduce its first jetliners . In 1966, American Airlines offered a specification to manufacturers for
6149-703: The United States House of Representatives investigated the cargo-door issue and the certification by the Federal Aviation Administration (FAA) of the original design. An airworthiness directive was issued, and all DC-10s underwent mandatory door modifications. The DC-10 experienced no more major incidents related to its cargo door after FAA-approved changes were made. On May 25, 1979, American Airlines Flight 191 crashed immediately after takeoff from Chicago O'Hare Airport . Its left engine and pylon assembly swung upward over
6292-517: The -55 were certified in 1961. The DC-8-51, DC-8-52 and DC-8-53 all had 17,000 lb (76.1 kN) JT3D-1 or 18,000 lb (80.6 kN) JT3D-3B engines, varying mainly in their weights: 276,000 pounds (125,200 kg), 300,000 pounds (136,100 kg) and 315,000 pounds (142,900 kg) respectively. The DC-8-55 arrived in June 1964, retaining the JT3D-3B engines but with strengthened structure from
6435-496: The -62 and -63. All three models were certified in 1982 and a total of 110 60-series Super DC-8s were converted by the time the program ended in 1988. DC-8 series 70 conversions were overseen by Cammacorp with CFMI, McDonnell Douglas, and Grumman Aerospace as partners. Cammacorp was disbanded after the last aircraft was converted. As of January 2024 , two DC-8s are in commercial service with Congolese cargo airline Trans Air Cargo . These are DC-8-62s (9S-AJG and 9S-AJO). In
6578-524: The 1971 estimate of 438 deliveries needed to break even on the program; however, according to Fielder, the DC-10 had not reached the breakeven point by the end of production. As the final DC-10s were delivered, McDonnell Douglas started production of its successor, the MD-11 , which was essentially a stretched derivative of the DC-10-30. In the late 1980s, international travel was on the rise thanks to lower oil prices and more economic freedom , leading to
6721-462: The 1980s and 1990s, but some re-engined DC-8s remain in use as freighters. At the end of World War II, Douglas was a dominant North American aircraft producer in the commercial aviation market, only being rivaled by Boeing , releasing the innovative all-metal Model 247 airliner in 1933, and produced prodigious quantities of the rugged four-engined B-17 Flying Fortress and sophisticated, pressurized long-range B-29 Superfortress . Douglas produced
6864-402: The 556 DC-8s made, around 200 were still in commercial service in 2002, including about 25 50-Series, 82 of the stretched 60-Series, and 96 out of the 110 re-engined 70-Series. Most of the surviving DC-8s are now used as freighters. In May 2009, 97 DC-8s were in service following UPS's decision to retire its remaining fleet of 44. In January 2013, an estimated 36 DC-8s were in use worldwide. As
7007-530: The 727, as its central engine bay would require an extremely expensive redesign to accommodate quieter high-bypass turbofans, and it was soon supplanted by Airbus with their A320 and Boeing with their 737 and 757 . Further advancements in high-bypass turbofan technology and subsequent relaxation in airline safety rules made the trijet and even the quadjet nearly obsolete for passenger services, as their range and payload could be covered more efficiently with large twinjets powered with purpose-designed engines such as
7150-525: The A300 and 767 twinjets. Thus trijet designs such as the DC-10 and L-1011 TriStar represented the best compromise with medium- to long-range and medium size that US airlines sought for their domestic and transatlantic routes. As a result of these trijet wide-bodies, as well as the popularity of the Boeing 727, in their heyday of the 1980s trijets made up a majority of all such US jet airliners. From 1985 to 2003
7293-539: The Advanced Common Flightdeck, which has "significant commonality" with that of the MD-11, thus eliminating the flight engineer and permitting the aircraft, re-designated MD-10 , to be flown by a flight crew of two. Three independent hydraulic systems are present. The flight controls actuate many of the flight control surfaces across the airliner via these hydraulic circuits. The critical nature of these circuits and their vulnerability to damage in
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#17327647434377436-497: 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
7579-457: The American aerospace company Convair . The legal relationship between McDonnell Douglas, Convair, and the Federal Aviation Administration (FAA) would later serve to complicate matters; specifically, Convair was forbidden from contacting the regulator no matter the severity of any safety concerns it had in the DC-10's design. On February 19, 1968, in what was supposed to be a knockout blow to
7722-526: The Americas, and one with the Panamanian start-up Cargo Three , also in the Americas. Non-airline operators included Omega Aerial Refueling Services with three DC-10 based KDC-10 tanker aircraft , the USAF with its 59 KC-10s, and the 10 Tanker Air Carrier with four modified DC-10-30s used for fighting wildfires. Orbis International has used a DC-10 as a flying eye hospital. Surgery is performed on
7865-562: The CFM56 was up to 23% more fuel-efficient than the JT3D, which reduced operating costs and extended the range. The largest single customer for the Series 70 was United, converting 29 of its Series 61 airliners at a reported cost of $ 400 million. By 2002, of the 1,032 Boeing 707s and 720s manufactured for commercial use, just 80 remained in service – though many of those 707s were converted for USAF use, either in service or for spare parts. Of
8008-453: The Comet remained grounded, the French 90-passenger twin jet Sud Aviation Caravelle prototype had just flown for the first time, and the Boeing 707 was not expected to be available until late 1958. The major airlines were reluctant to commit themselves to the huge financial and technical challenges of jet aircraft; however, none could afford not to buy jets if their competitors did. There
8151-469: The DC-10 achieved a long-term safety record comparable to those of similar-era passenger jets. The DC-10 outsold the similar Lockheed L-1011 TriStar due to the latter's delayed introduction and high cost. Production of the DC-10 ended in 1989, with 386 delivered to airlines along with 60 KC-10 tankers. It was succeeded by the lengthened, heavier McDonnell Douglas MD-11 . After merging with McDonnell Douglas in 1997, Boeing upgraded many in-service DC-10s as
8294-419: The DC-10 had been involved in 55 accidents and incidents , including 32 hull-loss accidents, with 1,261 occupant fatalities. Of these accidents and incidents, it has been involved in nine hijackings resulting in one death and a bombing resulting in 170 occupant fatalities. Despite its poor safety record in the 1970s, which gave it an unfavorable reputation, the DC-10 has proved to be a reliable aircraft with
8437-567: The DC-10's completion in light of the prospective competition and the high financial stakes involved. Together with American Airlines' announcement of the DC-10 order, it was also reported that American Airlines had declared its intention to have the British Rolls-Royce RB211 turbofan engine on its DC-10 airliners. The DC-10 was first ordered by launch customers American Airlines with 25 orders, and United Airlines with 30 orders and 30 options in 1968. The DC-10's similarity to
8580-559: The DC-10-30) is a tanker aircraft that was primarily operated by the United States Air Force . Early operations of the DC-10 were afflicted by its poor safety record, which was partially attributable to a design flaw in the original cargo doors that caused multiple incidents, including fatalities. Most notable was the crash of Turkish Airlines Flight 981 in Paris in 1974, the deadliest crash in aviation history up to that time. Following
8723-537: The DC-8, a feat that was eased by its fuselage keeping the same dimensions across its length. In April 1965, the company announced belated fuselage stretches for the DC-8 with three new models known as the Super Sixties . The DC-8 program had been in danger of closing with fewer than 300 aircraft sold, but the Super Sixties brought fresh life to it. By the time production of the DC-8 ceased in 1972, 262 of
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#17327647434378866-402: The DC-8. Douglas' refusal to offer different fuselage sizes made it less adaptable and compelled airlines such as Delta and United to look elsewhere for short to medium range types. Delta ordered Convair 880s while United chose the newly developed short-fuselage 707-020. United prevailed on Boeing to rename the new variant the Boeing 720 in case the public thought they were dissatisfied with
9009-530: The DC-8. In 1956, Air India, BOAC , Lufthansa , Qantas , and TWA added over 50 to the 707 order book, while Douglas sold 22 DC-8s to Delta, Swissair, TAI, Trans Canada , and UAT. By the start of 1958, Douglas had sold 133 DC-8s compared to Boeing's 150 707s. Donald Douglas proposed to build and test the DC-8 at Santa Monica Airport , which had been the birthplace of the DC-3 and home to a Douglas plant that employed 44,000 workers during World War II. To accommodate
9152-510: The DC-8. Pan Am never reordered the DC-8 and Douglas gradually lost market share to Boeing. In 1962, DC-8 sales dropped to just 26 aircraft that year, followed by 21 in 1963 and 14 in 1964; many of these later deliveries were of the Jet Trader model rather than the more-prestigious passenger versions. In 1967, Douglas merged with McDonnell Aircraft , becoming McDonnell Douglas . During the early 1960s, Douglas began considering stretching
9295-509: The ETOPS 330 standard), where the most direct route for some flights is over Antarctica . Since 2000, both narrow-body and wide-body trijet production has ceased for almost all commercial aircraft, being replaced by twinjets . As of 2016, the Falcon 7X, 8X, and 900 business jets, all of which use S-ducts , are the only trijets in production. Trijets that are no longer in production, such as
9438-653: The L-1011. Further models and derivatives of the DC-10 have been considered; perhaps the most radical of these being an unpursued twin-engined model akin to the Airbus A300 . However, following a spate of fatal accidents, particularly the American Airlines Flight 191 crash (the deadliest aviation accident in US history) orders for the DC-10 had nosedived by 1980, the type having garnered a poor reputation that
9581-558: The Lockheed L-1011 in design, passenger capacity, and launch date resulted in a sales competition that affected the profitability of both aircraft. On August 29, 1970, the first DC-10, a series 10, conducted its maiden flight . An extensive flight test program was carried out, totaling 929 flights and 1,551 flight hours; the test program was not incident-free: during one ground test in 1970, an outwardly-opening cargo door blew out and resulted rapid pressurization changes that caused
9724-424: The MD-11 to make it a twinjet but instead cancelled MD-11 production altogether. Trijets are more efficient and cheaper than four-engine aircraft, as the engines are the most expensive part of the plane and having more engines consumes more fuel, particularly if quadjets and trijets share engines of similar power. For widebody aircraft this makes the trijet configuration more suited to a mid-size airliner compared to
9867-418: The MD-11 would have competed with the 767 and 777. A study to remove the MD-11's tail-mounted engine (which would have made it a twinjet) never came to fruition as it would have been very expensive, and the MD-11 had very little in common in terms of design or type rating with other Boeing airliners. In contrast to McDonnell Douglas sticking with their existing trijet configuration, Airbus (which never produced
10010-458: The S-duct. Also, as the engine is located much higher up than the wing-mounted engines, engine failure will produce a greater pitching moment, making it more difficult to control. The placement of the remaining two engines varies. Most smaller aircraft, such as the Hawker Siddeley Trident and the Boeing 727 , as well as the intermediate-sized Tupolev Tu-154 , have two side-mount engine pylons in
10153-673: The Super Sixties had been completed, almost half of all models produced. With the ability to seat 269 passengers, the DC-8 Series 61 and 63 had the largest passenger-carrying capacity available. That remained so until the Boeing 747 arrived in 1970. The DC-8-62 featured a shorter fuselage when compared with the Series 61 and 63, but was capable of nonstop long-range operations. All of the earlier jetliners were relatively noisy by modern standards. Increasing traffic densities and changing public attitudes led to complaints about aircraft noise and moves to introduce restrictions. As early as 1966
10296-483: The U.S, the DC-8 has been retired from commercial service entirely; only one example maintains active registration (with one flying). Samaritan's Purse (a faith-based humanitarian relief organization) has operated a DC-8-72 Combi (acquired from Air Transport International ) since 2015. In 2024, NASA retired N817NA, a DC-8-72 flying laboratory that has supported research in meteorology, oceanography, geography, and various other scientific disciplines since 1986. NASA
10439-525: The United States, and banning all DC-10s from U.S. airspace. These measures were rescinded five weeks later on July 13, 1979, after the slat actuation and position systems were modified, along with stall warning and power supply changes. In November 1979, the FAA fined American Airlines for removing the engine and its pylon as a single unit in its maintenance procedure, thus damaging the structure and causing
10582-421: The air. Just four months after issuing the tanker requirement, the USAF ordered the first 29 KC-135 Stratotankers from Boeing. Donald Douglas was reportedly shocked by the rapidity of the decision which, he claimed, had been made before the competing companies even had time to complete their bids. He protested to Washington, but without success. Having already started on the DC-8 project, Douglas decided that
10725-435: The aircraft, Northwest's president asked that the "series 20" aircraft be redesignated "series 40" because the airliner was much improved over the original design. The FAA issued the certification for the series 40 on October 27, 1972. In 1972, the DC-10's listed unit cost was reportedly US$ 20M ($ 146 million in 2023 prices). The series 30 and 40 were longer-range "international" versions. The main visible difference between
10868-403: The best option was to press on than abandon the project. Following consultations with the airlines, several design changes were made, such as the fuselage being widened by 15 inches (38 cm) to permit six-abreast seating, which in turn led to larger wings and tail surfaces being adopted along with a lengthening of the fuselage. The existence of the DC-8 was formally announced on 7 June 1955; at
11011-415: The cargo door design to be dangerously flawed, as the door could be closed without the locking mechanism fully engaged, and this condition was not apparent from visual inspection of the door nor from the cargo-door indicator in the cockpit. The NTSB recommended modifications to make it readily apparent to baggage handlers when the door was not secured and also recommended adding vents to the cabin floor so that
11154-494: The cargo door, but the basic design remained unchanged, and problems persisted. On March 3, 1974, in an accident circumstantially similar to American Airlines Flight 96, a cargo-door blowout caused Turkish Airlines Flight 981 to crash near Ermenonville , France, in the deadliest air crash in history at the time—346 passengers and crew died. The cargo door of Flight 981 had not been fully locked, though it appeared so to both cockpit crew and ground personnel. The Turkish aircraft had
11297-571: The case of the Boeing 777 and 787 ) ETOPS 330 rating, and even ETOPS 370 for the Airbus A350 . As such, having more than two engines is no longer considered necessary, except for very large or heavy aircraft such as the Boeing 747 , Airbus A380 (over 400 seats in a mixed-class configuration), Antonov An-124 , and An-225 , or for flights through the Southern Hemisphere, primarily to and from Australia (which has not yet adopted
11440-601: 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. Permitting six-abreast seating, the four-engined , low-wing jet aircraft was initially produced in four 151 ft (46 m) long variants. The DC-8-10
11583-423: The competing Lockheed L-1011 , George A. Spater , President of American Airlines, and James S. McDonnell of McDonnell Douglas announced American Airlines' intention to acquire the DC-10. This was a shock to Lockheed and there was general agreement within the U.S. aviation industry that American Airlines had left its competitors at the starting gate. According to Fielder, McDonnell Douglas had been urgently pursuing
11726-644: The conversions. On January 8, 2007, Northwest Airlines retired its last remaining DC-10 from scheduled passenger service, thus ending the aircraft's operations with major airlines. Regarding the retirement of Northwest's DC-10 fleet, Wade Blaufuss, spokesman for the Northwest chapter of the Air Line Pilots Association said, "The DC-10 is a reliable airplane, fun to fly, roomy and quiet, kind of like flying an old Cadillac Fleetwood . We're sad to see an old friend go." Biman Bangladesh Airlines
11869-462: The crash of American Airlines Flight 191 , the deadliest aviation accident in U.S. history, the U.S. Federal Aviation Administration (FAA) temporarily banned all DC-10s from American airspace in June 1979. In August 1983, McDonnell Douglas announced that production would end due to a lack of orders, as it had widespread public apprehension after the 1979 crash and a poor fuel economy reputation. As design flaws were rectified and fleet hours increased,
12012-451: The distance required when landing. Despite being considerably larger, the landing speed of the DC-10 was comparable to that of the contemporary Boeing 727 . The primary flight controls of the DC-10 consist of inboard and outboard ailerons , two-section elevators , and a two-section rudder ; the secondary flight controls comprise leading edge slats , spoilers , and a dual-rate movable horizontal stabilizer . The vertical stabilizer with
12155-403: The early 1970s, several airlines approached McDonnell Douglas with requests for noise reduction modifications to their DC-8s. While third parties had developed aftermarket hushkits , there was initially no meaningful action taken by Douglas to fulfil these requests and effectively enable the DC-8 to remain in service. Finally, in 1975, General Electric began discussions with major airlines to fit
12298-407: The engine separation, rather than removing the engine from the pylon before removing the pylon from the wing as advised by McDonnell Douglas. On July 19, 1989, United Airlines Flight 232 crashed at Sioux City, Iowa , after an uncontained engine failure of the tail engine earlier in the flight disabled all hydraulic systems and rendered most flight controls inoperable. The flight crew, assisted by
12441-415: The engine). For example, the 727's central bay was only wide enough to fit a low-bypass turbofan and not the newer high-bypass turbofans which were quieter and more powerful. Boeing decided that a redesign was too expensive and ended its production instead of pursuing further development. The Lockheed Tristar's tail section was too short to fit an existing two-spool engine as it was designed only to accommodate
12584-563: The first MD-10 flew on April 14, 1999. The new cockpit eliminated the need for the flight engineer position and allowed common type rating with the MD-11. This has allowed companies such as FedEx Express , which operated both the MD-10 and MD-11, to use a common pilot pool for both aircraft. The MD-10 conversion now falls under the Boeing Converted Freighter program where Boeing's international affiliate companies perform
12727-408: The first time, in Series 10 form, on 30 May for two hours and seven minutes with the crew being led by A.G. Heimerdinger. Later that year, an enlarged version of the Comet finally returned to service, but had arrived too late to secure a substantial portion of the market: de Havilland secured just 25 orders. In August, Boeing had begun delivering 707s to Pan Am. Douglas made a massive effort to close
12870-429: The flight path of twin-engine jetliners was restricted to within 60 minutes' flying time from a suitable airport, in case of engine failure. In 1964, this rule was lifted for trijet designs, as they had a greater safety margin. For second-generation jet airliners, with the innovations of the high-bypass turbofan for greater efficiency and reduced noise, and the wide-body (twin-aisle) for greater passenger/cargo capacity,
13013-444: The freighter versions and 325,000-pound (147,420 kg) maximum weight. 142 DC-8-50s were built plus the 20 converted from Series 10/30/40. The Series 50 first flew on 20 December 1960 and received FAA certification on 1 May 1961. The DC-8-71, DC-8-72, and DC-8-73 were straightforward conversions of the -61, -62 and -63 primarily involving the replacement of the JT3D engines with the more fuel-efficient CFM International CFM56 -2,
13156-456: The gap with Boeing, using no fewer than ten aircraft for flight testing to achieve Federal Aviation Administration (FAA) certification for the first of the many DC-8 variants in August 1959. Several modifications proved to be necessary: the original air brakes on the lower rear fuselage were found to be ineffective and were deleted as engine thrust reversers had become available; unique leading-edge slots were added to improve low-speed lift;
13299-591: The ground and the operating room is located between the wings for maximum stability. In 2008, Orbis replaced its aging DC-10-10 with a DC-10-30 jointly donated by FedEx and United Airlines. The newer DC-10 was converted into an MD-10 configuration and began flying as an eye hospital in 2010. A modified DC-10 is operated by the Missile Defense Agency as the Widebody Airborne Sensor Platform (WASP). As of September 2015,
13442-416: The ground with one engine inoperative, approval can be granted to perform two-engine ferry flights. Prior to the introduction of ETOPS , only trijets and quadjets were able to perform long international flights over areas without any diversion airports. However, this advantage has largely disappeared in recent years as ETOPS-certified twin-engined aircraft are able to do so as well. Another major advantage of
13585-422: The initial flight being a round-trip flight between Los Angeles and Chicago. United Airlines also commenced DC-10 flights later that same month. American's DC-10s were configured to seat a maximum of 206 passengers while United's seated 222; both had six-across seating in first-class and eight-across (four pairs) in coach. They operated the first version of the DC-10, referred to as the "domestic" series 10, which had
13728-478: The jet airliner project, it believed that the USAF tanker contract would go to two companies for two different aircraft, as several USAF transport contracts in the past had done. In May 1954, the USAF circulated its requirement for 800 jet tankers to Boeing, Douglas, Convair , Fairchild Aircraft , Lockheed Corporation , and Martin Marietta . At the time, Boeing was only two months away from having its prototype in
13871-402: The later DC-8-50 and Super 60 (DC-8-61, -62, and -63) as well as freighter versions, and reached a MTOW of 325,000 lb (147 t). A stretched DC-8 variant was not initially considered, leading some airlines to order the competing Boeing 707 instead. The improved Series 60 was announced in April 1965. The DC-8-61 was stretched by 36 ft (11 m) for 180–220 seats in mixed-class and
14014-486: The long fuselage and the enlarged wing, freighters MTOW reached 355,000 lb (161 t). The DC-8 was produced until 1972 with 556 aircraft built; it was superseded by larger wide-body airliners including Douglas' DC-10 trijet. Noise concerns stimulated demand for a quieter variant; from 1975, Douglas and General Electric offered the Series 70 retrofit, powered by the quieter and more fuel-efficient CFM56 turbofan engine. It largely exited passenger service during
14157-405: The main cabin's floor to collapse. This discovery and first effort at rectification led to a contract dispute between McDonnell Douglas and Convair over what changes were necessary and financial liability. Fielder alleges that McDonnell Douglas consistently sought to minimize and postpone any design changes to the DC-10, although this attitude was not an explicit policy. In July 1971, Convair outlined
14300-581: The matter rested until October 1955, when Pan American World Airways placed simultaneous orders with Boeing for 20 707s and Douglas for 25 DC-8s. To buy one expensive and untried jet-powered aircraft type was brave: to buy both was, at the time, unheard of. In the closing months of 1955, other airlines rushed to follow suit: Air France , American Airlines, Braniff International Airways , Continental Airlines , and Sabena ordered 707s; United Airlines , National Airlines , KLM , Eastern Air Lines , Japan Air Lines , and Scandinavian Airlines System (SAS) chose
14443-403: The models is that the series 10 has three sets of landing gear (one front and two main) while the series 30 and 40 have an additional centerline main gear. The center main two-wheel landing gear (which extends from the center of the fuselage) was added to distribute the extra weight and for additional braking. The series 30 had a typical load range of 6,220 miles (5,410 nmi; 10,010 km) and
14586-409: The new and vastly-quieter Franco-American CFM56 engine to both DC-8s and 707s. MDC remained reluctant but eventually came on board in the late 1970s and helped develop the Series 70. The Super Seventies proved to be a great success, being roughly 70% quieter than the 60 Series and, at the time of their introduction, the world's quietest four-engined airliner. As well as being quieter and more powerful,
14729-459: The new jet bombers. The B-52, in particular, had to descend from its cruising altitude and then slow almost to its stall speed to refuel from the KC-97. Believing that a requirement for a jet-powered tanker was a certainty, Boeing started work on a new jet aircraft for this role that could be adapted into an airliner. As an airliner, it would have similar seating capacity to the Comet, but the use of
14872-427: The new jet, Douglas asked the city of Santa Monica, California to lengthen the airport's 5,000-foot (1,500-meter) runway. Following complaints by neighboring residents, the city refused, so Douglas moved its airliner production line to Long Beach Airport . In September 1956, production of the first prototype commenced. The first DC-8 N8008D was rolled out of the new Long Beach factory on 9 April 1958 and flew for
15015-512: The new three-spool Rolls-Royce RB211 engine, and delays in the RB211's development, in turn, pushed back the TriStar's entry into service which affected sales. The McDonnell Douglas DC-10 and related MD-11 use an alternative "straight-through" central engine layout, which allows for easier installation, modification, and access. It also has the additional benefit of being much easier to re-engine. However, this sacrifices aerodynamics compared to
15158-465: The number of such planes in service had sunk from 1488 to 602. The number of twinjets, on the other hand, had more than quadrupled in the same period. Both Lockheed and McDonnell Douglas were financially weakened competing in the widebody market, which led to Lockheed ending production of the L-1011 in 1984 after producing only half the units needed to break even, while a number of fatal DC-10 crashes also slowed its sales. In 1984 Boeing ended production of
15301-484: The original models of the Airbus A300 twinjet were limited to short- to medium-range distances. During this period, different jet airliners shared engines of similar output, such as when the McDonnell Douglas DC-10 , Airbus A300 , and Boeing 767 were powered by the General Electric CF6 , the additional power from the third engine gave the DC-10 advantages in longer range and/or heavier payload over
15444-528: The original wingtips used on the prototype, and all remaining DC-8 Series 10 aircraft were upgraded to DC-8-12 standard. The DC-8-12 featured the new low-drag wingtips and leading-edge slots , 80 inches long between the engines on each wing and 34 inches long inboard of the inner engines. These unique devices were covered by doors on the upper and lower wing surfaces that opened for low-speed flight and closed for cruise. The maximum weight increased from 265,000 to 273,000 pounds (120,200 to 123,800 kg). This model
15587-409: The outward force from pressurization of the fuselage at high altitudes, outward-opening doors must use heavy locking mechanisms. In the event of a door lock malfunction, there is greater potential for explosive decompression . On June 12, 1972, American Airlines Flight 96 lost its aft cargo door above Windsor, Ontario . Before takeoff, the door appeared secure, but the internal locking mechanism
15730-539: The plane slightly less stable and more complex to handle during takeoff and landing. (The McDonnell Douglas DC-9 twinjet and its derivatives, whose engines are mounted on pylons near the rear empennage , have similar advantages/disadvantages of the trijet design, such as the wings located further aft and a more rearward center of gravity.) The first trijet design to fly was the Tupolev Tu-73 bomber prototype, first flown in 1947. The first commercial trijets were
15873-530: The plans for the DC-10-50 were abandoned after British Airways ordered the Lockheed L-1011-500 instead. Beginning in 1966, two-engine designs were studied for the DC-10 before the design settled on the three-engine configuration. Later, a big twin based on the DC-10 cross-section was proposed to Airbus as a 50/50 venture but was rejected. Then in 1971, a shortened DC-10 version with two engines
16016-431: The pressure difference between the cabin and cargo bay during decompression could quickly equalize without causing further damage. Although many carriers voluntarily modified the cargo doors, no airworthiness directive was issued, due to a gentlemen's agreement between the head of the FAA, John H. Shaffer , and the head of McDonnell Douglas's aircraft division, Jackson McGowen. McDonnell Douglas made some modifications to
16159-497: The prototype was 25 kn (46 km/h) short of its promised cruising speed and a new, slightly larger wingtip had to be developed to reduce drag . Also, a recontoured wing leading edge was later developed to extend the chord 4% and reduce drag at high Mach numbers. On August 21, 1961, a DC-8 broke the sound barrier at Mach 1.012 (660 mph/1,062 km/h) while in a controlled dive through 41,000 feet (12,497 m) and maintained that speed for 16 seconds. The flight
16302-455: The quadjet layout for jumbo jets (i.e. the DC-10 versus the quadjet Boeing 747 ). However the difficulty and complexity of mounting the third engine through the tail will somewhat negate the cost/efficiency advantage. Nonetheless, this was worth the trade-off in the 1960s to the 1990s when widebody trijets and twinjets shared engines of similar output, such as when the DC-10, MD-11, Boeing's 767, and Airbus's A300, A310, and A330 were all powered by
16445-411: The rudder is mounted on top of the tail engine banjo while the horizontal stabilizer with its four-segment elevator is attached to the sides of the rear fuselage conventionally. The DC-10 is equipped with retractable tricycle landing gear . To enable higher gross weights, the later –30 and –40 series have an additional two-wheel main landing gear, which retracts into the center of the fuselage. The DC-10
16588-419: The runway is an issue. Unlike twinjets, trijets are not required to land immediately at the nearest suitable airport if one engine fails. (This advantage is also shared with quadjets.) This is advantageous if the aircraft is not near one of the operator's maintenance bases, as the pilots may then continue the flight and land at an airport where it is more suitable to perform repairs. Additionally, for trijets on
16731-436: The same tasks as most trijets and even many quadjets but more efficiently. Due to their added thrust, trijets will have slightly improved takeoff performance compared to twinjets if an engine fails. Because takeoff performance for aircraft is usually calculated to include an extra margin to account for a possible engine failure, trijets are better able to take off from hot and high airports or those where terrain clearance near
16874-414: The situation in a formal memo; almost a year later, it internally expressed concerns that the inadequate resolution would lead to loss of aircraft. Tragically, the initial rectification work would prove to be inadequate. On July 29, 1971, the FAA issued the type certificate for the DC-10, permitting its entry into revenue service. It entered commercial service with American Airlines on August 5, 1971, with
17017-400: The smaller lower level is typically used for storage for baggage and food preparation; elevators are usually present to carry people and carts between the two levels. As originally designed, the floor of the main cabin was not strong enough to withstand full pressure differential, yet key control lines are routed through this floor, an approach that proved to be a key vulnerability. The DC-10
17160-498: The tail area led to the addition of hydraulic fuses to prevent the total loss of fluid. Power for the hydraulics was derived from primary and reserve engine-driven pumps equipped on each of the three engines. Hydraulic power was required for flight control, there was no provision for reverting to manual flight control inputs. A proposed version of the DC-10-10 with extra fuel tanks, 3 feet (91 cm) extensions on each wingtip, and
17303-558: The tail engine, the engine failure ruptured all three, resulting in a total loss of control of the elevators, ailerons, spoilers, horizontal stabilizers, rudder, flaps, and slats. Following the accident, hydraulic fuses were installed in the #3 hydraulic system below the tail engine on all DC-10 aircraft to ensure that sufficient control remains if all three hydraulic systems are damaged in this area. Related development Aircraft of comparable role, configuration, and era Related lists Trijet The Dassault Falcon 7X /8X and
17446-460: The time of the announcement, the development costs had been forecast to be roughly $ 450 million. Four versions were offered to begin with, all with the same 150-foot-6-inch (45.87 m) long airframe with a 141-foot-1-inch (43.00 m) wingspan, but varying in engines and fuel capacity, and with maximum weights of about 240,000–260,000 lb (109–118 metric tons). Douglas steadfastly refused to offer different fuselage sizes. The maiden flight
17589-523: The top of the wing, severing the leading edge slat actuator hydraulic lines. The slats retracted under the aerodynamic forces , causing the left wing to stall . This, combined with asymmetric thrust due to the missing engine, caused the aircraft to rapidly roll to the left, descend, and crash, killing all 271 people on board and two on the ground. Following the crash, the FAA withdrew the DC-10's type certificate on June 6, 1979, grounding all U.S.-registered DC-10s and those from nations with agreements with
17732-433: The trijet design is that the wings can be located further aft on the fuselage, compared to twinjets and quadjets with all wing-mounted engines, allowing main cabin exit and entry doors to be more centrally located for quicker boarding and deplaning, ensuring shorter turnaround times. The rear-mounted engine and wings shift the aircraft's center of gravity rearwards, improving fuel efficiency , although this will also make
17875-424: The trijet design was seen as the optimal configuration for the medium wide-body jet airliner, sitting in terms of size, range, and cost between quadjets (four-engine aircraft) and twinjets, and this led to a flurry of trijet designs. The four-engine Boeing 747 was popular for transoceanic flights due to its long-range and large size, but it was expensive and not all routes were able to fill its seating capacity, while
18018-485: Was accompanied to altitude by a F-104 Starfighter supersonic chase aircraft flown by Chuck Yeager . On September 18, 1959, the DC-8 entered service with Delta Air Lines and United Airlines. According to the Delta Air Lines website, the air carrier was the first to operate the DC-8 in scheduled passenger service. By March 1960, Douglas had reached its planned production rate of eight DC-8s per month. Despite
18161-784: Was certified in March 1960 with 16,800 lb (75.2 kN) JT4A-9 engines for 300,000-pound (136,080 kg) maximum takeoff weight. The DC-8-32 was similar but allowed 310,000-pound (140,600 kg) weight. The DC-8-33 of November 1960 substituted 17,500 lb (78.4 kN) JT4A-11 turbojets, a modification to the flap linkage to allow a 1.5° setting for more efficient cruise, stronger landing gear, and 315,000-pound (142,880 kg) maximum weight. Many -31 and -32 DC-8s were upgraded to this standard. A total of 57 DC-8-30s were produced (five of which were later upgraded to DC-8-50 standard). The Series 30 DC-8 first flew on 21 February 1959 and received FAA certification on 1 February 1960. The DC-8-40
18304-480: Was due in early 1961. The DC-8-41 and DC-8-42 had weights of 300,000 and 310,000 pounds (140,000 and 140,000 kg) respectively, the 315,000-pound (142,880 kg) DC-8-43 had the 1.5° flap setting of the -33 and introduced a 4% leading-edge wing extension to reduce drag and increase fuel capacity slightly – the new wing improved range by 8%, lifting capacity by 6,600 lb (3 metric tons), and cruising speed by better than 10 knots (19 km/h; 12 mph). It
18447-405: Was essentially the -30 but with 17,500 lb (78.4 kN) Rolls-Royce Conway 509 turbofan engines for better efficiency, less noise and less smoke. The Conway was an improvement over the turbojets that preceded it, but the Series 40 sold poorly because of the traditional reluctance of U.S. airlines to buy a foreign product and because the still-more-advanced Pratt & Whitney JT3D turbofan
18590-503: Was for a four-engine double-deck wide-body jet airliner with a maximum seating capacity of 550 passengers and similar in length to a DC-8 . The proposal was shelved in favor of a trijet single-deck wide-body airliner with a maximum seating capacity of 399 passengers, and similar in length to the DC-8 Super 60. Large portions of the detailed design work, particularly that of the fuselage, were subcontracted to external companies, such as
18733-416: Was grounded in 1954 after two fatal accidents which were subsequently attributed to rapid metal fatigue failure of the pressure cabin. Various aircraft manufacturers benefited from the findings and experiences gained from the investigation into Comet losses; specifically, Douglas paid significant attention to detail in the design of the DC-8's pressurized cabin. By 1952, Douglas had continued its success as
18876-445: Was in service and proving popular with passengers and airlines: it was faster, quieter, and more comfortable than piston-engined types. Another British rival was the 90-seat Bristol Britannia , and Douglas's main rival in the large airliner market, Lockheed Corporation , had committed to the short to medium range 80–100-seat turboprop Electra , with a launch order from American Airlines for 35 and other orders flowing in. Meanwhile,
19019-431: Was not fully engaged. When the aircraft reached approximately 11,750 feet (3,580 m) in altitude, the door blew out, and the resulting explosive decompression collapsed the cabin floor. Many control cables to the empennage were cut, leaving the pilots with very limited control of the aircraft. Despite this, the crew performed a safe emergency landing. U.S. National Transportation Safety Board (NTSB) investigators found
19162-621: Was originally named "DC-8A" until the series 30 was introduced. 30 DC-8-10s were built: 23 for United and six for Delta, plus the prototype. By the mid-sixties, United had converted 16 of its 21 surviving aircraft to DC-8-20 standard and the other five to -50s. Delta converted its six to DC-8-50s. The prototype was itself also converted to a DC-8-50. It received FAA certification on 31 August 1958, entering service with United Airlines and Delta Air Lines on 18 September 1959. Higher-powered 15,800 lb (70.8 kN) thrust Pratt & Whitney JT4A -3 turbojets (without water injection) allowed
19305-508: Was originally planned to use three engines, with the third engine installed in the tail with a Y-shaped duct and air intakes on both sides of the rear. However, a revised design with four engines located under a delta wing was unveiled at the Farnborough Airshow on July 19, 2022. Douglas DC-8 The Douglas DC-8 (sometimes McDonnell Douglas DC-8 ) is an early long-range narrow-body jetliner designed and produced by
19448-404: Was planned for December 1957, with entry into revenue service in 1959. Aware that the program was lagging behind Boeing, Douglas began a major marketing push to promote its new jetliner. Douglas' previous thinking about the airliner market seemed to be coming true; the transition to turbine power looked likely to be to turboprops rather than turbojets. The pioneering 40–60-seat Vickers Viscount
19591-491: Was powered by Pratt & Whitney JT3C turbojets, and had a 273,000 lb (124 t) MTOW ; the DC-8-20 had more powerful JT4A turbojets, for a 276,000 lb (125 t) MTOW. The intercontinental models had more fuel capacity, and had an MTOW of up to 315,000 lb (143 t); it was powered by JT4As for the Series 30, and by Rolls-Royce Conway turbofans for the Series 40. The Pratt & Whitney JT3D powered
19734-424: Was proposed as a competitor to the Airbus A300 . McDonnell Douglas held a major presentation of the proposed DC-10 Twin at Long Beach, and several European airlines were willing to place orders. However on July 30, 1973, MDC's board decided not to give the proposed twin the go-ahead, as no US airline had ordered it. Later, more DC-10 Twin proposals were made, either as a collaboration with a European manufacturer or as
19877-407: Was seen as highly beneficial for maintenance purposes as well as to increase wing volume for accommodating fuel. The fuselage featured a double-bubble cross-section that produced relatively low drag while providing for a relatively spacious passenger cabin along with a large cargo deck that was sufficiently tall as to permit ground crews to stand up within it. While Douglas remained lukewarm about
20020-480: Was the last commercial carrier to operate the DC-10 in passenger service. The airline flew the DC-10 on a regular passenger flight for the last time on February 20, 2014, from Dhaka , Bangladesh to Birmingham , UK. Local charter flights were flown in the UK until February 24, 2014. As of September 2024, two DC-10s are in commercial service, one with TAB Airlines , a Bolivian cargo airline operating scheduled flights in
20163-614: Was to collect data on a new leading edge design for the wing, and, while doing so, the DC-8 became the first civilian jet – and the first jet airliner – to make a supersonic flight. The aircraft was DC-8-43 registered as CF-CPG , later delivered to Canadian Pacific Air Lines . The aircraft, crewed by Captain William Magruder, First Officer Paul Patten, Flight Engineer Joseph Tomich and Flight Test Engineer Richard Edwards, took off from Edwards Air Force Base in California and
20306-469: Was used on all later DC-8s. The first DC-8-40 was delivered in 1960; 32 were built (of which three would eventually be converted to DC-8-50s). The Series 40 DC-8 first flew on 23 July 1959 and received FAA certification on 24 March 1960. The definitive short-fuselage DC-8 came with the same engine that powered the vast majority of 707s, the JT3D . Twenty earlier DC-8s were converted to this standard. All but
20449-549: Was widespread amongst the traveling public as well as prospective operators. Competitive pressure had also played a role, Boeing in particular had developed the 747SP variant specifically to better compete with the DC-10 and L-1011. In December 1988, the 446th and final DC-10 rolled off the Long Beach, California Products Division production line and was delivered to Nigeria Airways in July 1989. The production run had exceeded
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