The McDonnell Douglas DC-9 (initially known as the Douglas DC-9) is a twin-engine, single-aisle jet airliner. It was first manufactured in 1965 with its maiden flight later that year. The DC-9 was designed for frequent, short flights. The final DC-9 was delivered in October 1982.
The DC-9 was followed in subsequent modified forms by the MD-80, MD-90 and Boeing 717. With the final two deliveries of the 717 in 2006, production of the DC-9/MD-80/90/717 aircraft family ceased after 41 years and over 2,400 units built.
Origins
During the 1950s Douglas Aircraft studied a short-medium range airliner to complement its higher capacity, long range DC-8. (DC stands for Douglas Commercial.[1]) A medium range four-engine Model 2067 was studied but did not receive enough interest from airlines and was abandoned. In 1960 Douglas signed a two-year contract with Sud Aviation for technical cooperation. Douglas would market and support the Sud Aviation Caravelle and produce a licensed version if airlines ordered large numbers, but none were ordered and Douglas returned to its design studies after the two years.[2]
Northwest Airlines (NWA) DC-9 T-tail at Regina International Airport
In 1962 design studies were underway. The first version seated 63 passengers and had a gross weight of 69,000 lb (31,300 kg). This design was changed into what would be initial DC-9 variant.[2] Douglas gave approval to produce the DC-9 on April 8, 1963.[2] Unlike the competing but larger Boeing 727 trijet, which used as many 707 components as possible, the DC-9 was an all-new design. The DC-9 has two rear fuselage-mounted Pratt & Whitney JT8D turbofan engines, relatively small, efficient wings, and a T-tail.[3] The DC-9's takeoff weight was limited to 80,000 lb (36,300 kg) for a two-person flight crew by Federal Aviation Agency regulations at the time.[2] DC-9 aircraft have 5 seats across for economy seating. The airplane seats 80 to 135 passengers depending on version and seating arrangement.
The DC-9 was designed for short to medium routes, often to smaller airports with shorter runways and less ground infrastructure than the major airports being served by larger designs like the 707 and DC-8. Consequently, accessibility and short field characteristics were called for. The tail mounted engine design facilitated a clean wing design without engine pods, which had numerous advantages. flaps could be longer, unimpeded by pods on the leading edge and engine blast concerns on the trailing edge. This simplified design, improved airflow at low speeds and enabled lower takeoff and approach speeds, thus lowering field length requirements and keeping wing structure light. The second advantage of the tail-mounted engines was the reduction in foreign object damage from ingested debris from runways and aprons. Third, the absence of engines in underslung pods allowed a reduction in ground clearance, making the aircraft more accessible to baggage handlers and passengers. Turnarounds were simplified by built-in airstairs, including one in the tail, which shortened boarding and deplaning times. The problem of deep stalling, revealed by the loss of the BAC One-Eleven prototype in 1963, was overcome through various changes, including the introduction of vortilons, small surfaces beneath the wing's leading edge used to control airflow and increase low speed lift.[4]
[edit]Into production
C-9 Nightingale used for Aeromedical Evacuation
The first DC-9, a production model, flew on February 25, 1965.[5] The second DC-9 flew a few weeks later,[3] with a test fleet of five aircraft flying by July. This allowed the initial Series 10 to gain airworthiness certification on November 23, 1965 and to enter service with Delta Air Lines on December 8.[5] The DC-9 was always intended to be available in multiple versions to suit customer requirements,[6] and the first stretched version, the Series 30, with a longer fuselage and extended wing tips, flew on August 1, 1966, entering service with Eastern Air Lines in 1967.[5] The initial Series 10 would be followed by the improved -20, -30, and -40 variants. The final DC-9 series was the -50, which first flew in 1974.[3]
In 1967, the US Air Force selected the DC-9 to meet their requirement for an medical evacuation (MedEvac) and passenger transport aircraft, designated as the C-9A Nightingale; deliveries began in 1968.[7] The U.S. Navy also ordered five C-9Bs for passenger and cargo duties in April 1972.[7] The C-9B aircraft have provided air logistics support for the Navy and Marine Corps. A C-9B was also chosen by NASA for reduced gravity research.[8] Some C-9s were converted from former civilian DC-9s; three were also specially configured for VIP transport duties.[9] Kuwait also operated a small C-9 fleet.[9] All USAF C-9s were retired by 2005.[10]
A Cebu Pacific DC-9 in 2006
The DC-9 was a commercial success with 976 built when the production ended in 1982.[3] The DC-9 is one of the longest lasting aircraft in operation. Its reliability and efficiency led to sales of its successors into the 21st century.[citation needed] The DC-9 family is one of the most successful jet airliners with a total of over 2,400 units produced; it ranks third behind the second place Airbus A320 family with over 5,000 produced, and the first place Boeing 737 with over 7,000 produced.
Studies aimed at further improving DC-9 fuel efficiency, by means of retrofitted wingtips of various types, were undertaken by McDonnell Douglas. However these did not succeed in demonstrating significant benefits, especially with existing fleets shrinking. The wing design makes retrofitting difficult.[11]
[edit]Legacy
The DC-9 was followed by the introduction of the MD-80 series in 1980. The MD-80 series was originally called DC-9-80 series. It was a lengthened DC-9-50 with a higher maximum takeoff weight (MTOW), a larger wing, new main landing gear, and higher fuel capacity. The MD-80 series features a number of variants of the Pratt & Whitney JT8D turbofan engine having higher thrust ratings than those available on the DC-9.
The MD-80 series was further developed into the McDonnell Douglas MD-90 in the early 1990s. It has yet another fuselage stretch, a glass cockpit (first introduced on the MD-88) and completely new International Aero V2500 high-bypass turbofan engines. In comparison to the very successful MD-80, relatively few MD-90 examples were built.
The final variant of the DC-9 family was the MD-95, which was renamed the Boeing 717-200 after McDonnell Douglas's merger with Boeing in 1997 and before aircraft deliveries began. The fuselage length and wing are highly similar to those found on DC-9-30 aircraft, but much use was made of lighter, modern materials. Power is supplied by two BMW/Rolls-Royce BR715 high bypass turbofan engines.
China's Comac ARJ21 is derived from the DC-9 family. The ARJ21 is built with manufacturing tooling from the MD-90 Trunkliner program. Consequently it has the same fuselage cross section, nose profile, and tail.[12]
[edit]Variants
British Midland Airways DC-9-15
[edit]Series 10
The original DC-9 (later designated the Series 10) was the smallest DC-9 series. The -10 was 104.4 ft (31.8 m) long and had a maximum weight of 82,000 lb (37,000 kg). The Series 10 was similar in size and configuration to the BAC One-Eleven and featured a T-tail and rear mounted engines. Power was a pair of 12,500 lbf (56 kN) Pratt & Whitney JT8D-5 or 14,000 lbf (62 kN) JT8D-7 engines. A total of 137 were built. Delta Air Lines was the initial operator.
The Series 10 was produced in two main subvariants, the Series 14 and 15, although of the first four aircraft, three were built as Series 11s and one as Series 12. These were later converted to Series 14 standard. No Series 13 was produced. A passenger/cargo version of the aircraft with a 136 x 81 in side cargo door forward of the wing and a reinforced cabin floor, was certificated on March 1, 1967. Cargo versions included the Series 15MC (Minimum Change) with folding seats which can be carried at the rear of the aircraft, and the Series 15RC (Rapid Change) with seats removable on pallets. These differences disappeared over the years as new interiors have been installed.[13][14]
The Series 10 was unique in the DC-9 family in not having leading edge slats. The Series 10 was designed to have short takeoff and landing distances without the use of leading edge high-lift devices. Therefore, the wing design of the Series 10 featured airfoils with extremely high maximum lift capability in order to obtain the stalling speeds necessary for short field performance.[15]
[edit]Series 10 features
The Series 10 has an overall length of 104.4 feet (31.82 m), a fuselage length of 92.1 feet (28.07 m), a passenger cabin length of 60 feet (18.29 m), and a wingspan of 89.4 feet (27.25 m).
The Series 10 was offered with the 14,000 lbf (62 kN) thrust JT8D-1 and JT8D-7.[13][14]
All versions of the DC-9 are equipped with an AlliedSignal (Garrett) GTCP85 APU as standard which is located in the aft fuselage.[13][14]
The Series 14 was originally certificated at an MTOW of 85,700 lb (38,900 kg) but subsequent options offer increases to 86,300 and 90,700 lb (41,100 kg). The aircraft's MLW in all cases is 81,700 lb (37,100 kg). The Series 14 has a fuel capacity of 3,693 US gallons (with the 907 US gal centre section fuel). The Series 15, certificated on January 21, 1966, is physically identical to the Series 14 but has the increased MTOW of 90,700 lb (41,100 kg). Typical range with 50 passengers and baggage is 950 nmi (1,760 km), increasing to 1,278 nmi (2,367 km) at long range cruise. Range with maximum payload is 600 nmi (1,100 km), increasing to 1,450 nmi (2,690 km) with full fuel.[13][14]
The DC-9 Series 10, as with all later versions of the DC-9 is equipped with a two crew analog flightdeck.[13][14]
The aircraft is fitted with a passenger door in the port forward fuselage, and a service door/emergency exit is installed opposite. An airstair installed below the front passenger door was available as an option as was an airstair in the tailcone. This also doubled as an emergency exit. Available with either two or four overwing exits, the DC-9-10 can seat up to a maximum certified exit limit of 109 passengers. Typical all economy layout is 90 passengers, and 72 passengers in a more typical mixed-class layout with 12 first and 60 economy-class passengers.[13][14]
All versions of the DC-9 are equipped with a tricycle undercarriage, featuring a twin nose unit and twin main units.[13][14]
[edit]Series 20
Scandinavian Airlines DC-9-21
The Series 20 was designed to satisfy a Scandinavian Airlines request for improved short field performance by using the more powerful engines and improved wings of the -30 combined with the shorter fuselage used in the -10. Ten Series 20 aircraft were produced, all of them Model -21.[16]
In 1969, a DC-9 Series 20 at Long Beach was fitted with an Elliott Flight Automation Head-up display by McDonnell Douglas and used for successful three month-long trials with pilots from various airlines, the Federal Aviation Administration, and the US Air Force.[17]
[edit]Series 20 features
The Series 20 has an overall length of 104.4 feet (31.82 m), a fuselage length of 92.1 feet (28.07 m), a passenger cabin length of 60 feet (18.29 m), and a wingspan of 93.3 feet (28.44 m).[13][14]
The DC-9 Series 20 is powered by the 15,000 lbf (67 kN) thrust JT8D-11 engine.[13][14]
The Series 20 was originally certificated at an MTOW of 94,500 lb (42,900 kg) but this has been increased to 98,000 lb (44,000 kg), some 8% up on the higher weight Series 14s and 15s. The aircraft's MLW is 95,300 lb (43,200 kg) and MZFW is 84,000 lb (38,000 kg). Typical range with maximum payload is 1,000 nmi (1,900 km), increasing to 1,450 nmi (2,690 km) with maximum fuel. The Series 20, using the same wing as the Series 30 and indeed the Series 40 and 50, has a slightly lower basic fuel capacity than the Series 10 (3,679 US gallons).[13][14]
[edit]Series 20 milestones
First flight: September 18, 1968.
FAA certification: November 25, 1968.
First delivery: December 11, 1968 to SAS
Entry into service: January 27, 1969 with SAS.
Last delivery: May 1, 1969 to SAS.
[edit]Series 30
Ex-Spirit Airlines DC-9-30 Firebird II, highly modified as a surveillance aircraft for the U.S. Navy, based at Mojave Airport
The -30 was the definitive series, produced to counter Boeing's 737 twinjet, with 662 produced, accounting for about 60% of production. The -30 entered service with Eastern Airlines in February 1967 with a 14 ft 9 in (4.50 m) fuselage stretch, wingspan increased by just over 3 ft (0.9 m) and full-span leading edge slats, improving takeoff and landing performance. Gross take-off weight was typically 110,000 lb (50,000 kg). Engine options for Models -31, -32, -33 and -34 included the P&W JT8D-7 and JT8D-9 rated at 14,500 lbf (64 kN) of thrust, or JT8D-11 rated at 15,000 lbf (67 kN) of thrust.
The Series 30 was designed to incorporate extremely effective leading edge devices in order to reduce the landing approach speeds exhibited by the Series 10, at substantially higher maximum landing weights. The addition of full-span leading edge slats reduced approach speeds by 6 knots, despite the gross weight being 5000 lbs greater. The full span slats offered a significant weight advantage over slotted Krueger flaps, since the wing leading edge structure associated with the slat is a more efficient torque box than the structure associated with the slotted Krueger. The wing also had a 6% increase in wing chord, all ahead of the front spar. This increase in wing chord allowed the 15% chord slat to be incorporated.[18]
[edit]Series 30 subvariants
TAA DC-9-30 at Melbourne Airport, 1987
The Series 30 was produced in four main sub-variants.[13][14]
DC-9-31: Produced in passenger version only. The first DC-9 Series 30 flew on August 1, 1966, and the first delivery was made to Eastern Airlines on February 27, 1967 following certification on December 19, 1966. Basic MTOW of 98,000 lb (44,000 kg) and subsequently certificated at various increased weights up to 108,000 lb (49,000 kg).
DC-9-32: Introduced in the first year of production (1967). Certificated March 1, 1967. Basic MTOW of 108,000 lb (49,000 kg) and subsequently increased to 110,000 lb (50,000 kg). A number of cargo versions of the Series 32 were also produced including:
32LWF (Light Weight Freight) with modified cabin but no cargo door or reinforced floor, intended for package freighter use.
32CF (Convertible Freighter), with a reinforced floor but retaining passenger facilities
32AF (All Freight), a windowless all-cargo aircraft.
DC-9-33: Following the Series 31 and 32 came the Series 33, intended for passenger/cargo or all-cargo use. Certificated on April 15, 1968, the aircraft's MTOW was increased to 114,000 lb (52,000 kg), MLW to 102,000 lb (46,000 kg) and MZFW to 95,500 lb (43,300 kg). JT8D-9 or -11 (15,000 lbf (67 kN) thrust) engines were used. In addition, the wing incidence was increased 1.25 degrees, to reduce cruise drag.[19] Only 22 were built, as All Freight (AF), Convertible Freight (CF) and Rapid Change (RC) aircraft.
DC-9-34: The last version of the aircraft to be developed was the Series 34, intended for use on longer range routes with an MTOW of 121,000 lb (55,000 kg), an MLW of 110,000 lb (50,000 kg) and an MZFW of 98,000 lb (44,000 kg). The DC-9-34CF (Convertible Freighter) was certificated April 20, 1976, while the passenger followed on November 3, 1976. The aircraft is equipped with the more powerful JT8D-9s with the -15 and -17 engines as an option. It also included the wing incidence change introduced on the DC-9-33. Twelve were built, five as convertible freighters.
[edit]Series 30 features
The DC-9-30 was offered with a selection of variants of JT8D including the -1, -7, -9, -11, -15 and -17. The most common on the Series 31 is the JT8D-7 (14,000 lbf (62 kN) thrust), although it was also available with the -9 and -17 engines. On the Series 32 the JT8D-9 (14,500 lbf (64 kN) thrust) was standard, with the -11 also offered. The Series 33 was offered with the JT8D-9 or -11 (15,000 lbf (67 kN) thrust) engines and the heavyweight -34 with the JT8D-9, -15 (15,000 lbf (67 kN) thrust) or -17 (16,000 lbf (71 kN) thrust) engines.[13][14]
[edit]Series 40
DC-9-40 flight deck
This further lengthened version entered service with SAS in March 1968. With a 6 ft 6 in (2 m) longer fuselage, accommodation was up to 125 passengers. The -40 was fitted with Pratt & Whitney engines of between 14,500 and 16,000 lbf (64 and 71 kN). A total of 71 were produced.
[edit]Series 50
The -50 was the largest DC-9 to fly. It features an 8 ft 2 in (2.49 m) fuselage stretch and seats up to 139 passengers. It started revenue service in August 1975 with Eastern Airlines and included a number of detail improvements, a new cabin interior, and more powerful JT8D-15 or -17 engines in the 16,000 and 16,500 lbf (71 and 73 kN) class. McDonnell Douglas delivered 96, all as Model -51. Some visual cues to distinguish this version from other DC-9 variants include side strakes (fins) below the side cockpit windows and thrust reversers rotated about 22 degrees on the original configuration. However various maintenance replacements have seen the thrust reversers in the same position as the -30 and -40.
For later DC-9 variants, see McDonnell Douglas MD-80, McDonnell Douglas MD-90, and Boeing 717.
Delta DC-9-51 Interior Cabin View N779NC
[edit]Military and government
A US Air Force C-9A Nightingale
C-9A Nightingale - 23 aeromedical evacuation aircraft for the United States Air Force received from 1968.[9] The final active-duty flight of the C-9A was in September 2005.[20] The last C-9A was flown to Andrews AFB Museum in September 2012.[21][verification needed]
C-9B Skytrain II - 24 convertible passenger/transport versions for the United States Navy and Marine Corps delivered from 1973 to 1976. An additional five C-9s were converted from passenger configured DC-9s.[9]
VC-9C - 3 executive transport aircraft for the United States Air Force.[9] The three aircraft were delivered to the US Air Force in late 1976.
C-9K - 2 DC-9-30C for the Kuwait Air Force.[9]
[edit]Operators
Two British Midland DC-9s at Teesside Airport in 1994.
Perris Valley Skydiving DC-9-21, January 2008
A total of 129 DC-9 aircraft (all variants) were in commercial service as of November 2011, including Delta Air Lines (21),[22] USA Jet Airlines (7), Everts Air Cargo (5), Aeronaves TSM (4), Aserca Airlines (4),[23] LASER Airlines (4), and other operators with fewer aircraft.[24][25]
Delta Air Lines has, since acquiring Northwest Airlines, operated a fleet of DC-9 aircraft, most of which are over 30 years old. With severe increases in fuel prices in the summer of 2008, Northwest Airlines finally began retiring its DC-9s, switching to Airbus A319s that are 27% more fuel efficient.[26][27]
Because of the usage of the aging JT8D engines, as of late 2000s (decade) DC-9s are considered gas guzzlers when compared to other more recent airliner designs. Studies aimed at improving DC-9 fuel efficiency, by means of retrofitted wingtip extensions of various types, have not succeeded in demonstrating significant benefits.
With the existing DC-9 fleet shrinking, modifications do not appear to be likely to occur, especially since the wing design makes retrofitting difficult.[11] Thus, DC-9s are likely to be further replaced in service by new Boeing 737, Airbus A320, Embraer E-Jets aircraft, or the new, emerging Bombardier CSeries airliner.[28] However, it is probable that a modest number of DC-9s will continue to productively fly for many years to come. As the Northwest/Delta merger progressed, Delta pulled several stored DC-9s back into service.
One ex-SAS DC-9-21 is operated as a skydiving jump platform at Perris Valley Airport in Perris, California. With the steps on the ventral stairs removed, it is the only airline transport class jet certified to date by the FAA for skydiving operations as of 2008.[29]
Accidents and incidents
As of March 2009, the DC-9 has been involved in 117 incidents, including 101 hull-loss accidents,[31] with 2,135 fatalities.[32]
[edit]Notable accidents
On October 1, 1966, West Coast Airlines Flight 956 crashed with eighteen fatalities and no survivors. This accident marks the first loss of a DC-9.[33]
On March 9, 1967, TWA Flight 553 fell to earth in a field in Concord Township, near Urbana, Ohio, following a mid-air collision with a Beechcraft Baron, an accident which triggered substantial changes in air traffic control procedures.[34] All 25 people on board the DC-9 were killed.
On March 17, 1969, Viasa Flight 742 crashed into the La Trinidad neighborhood of Maracaibo during a failed take-off. All 84 people on board the aircraft as well as 71 people on the ground were killed. At that time Viasa Flight 742 was the worst disaster in aviation history.[35]
On June 27, 1969, Douglas DC-9-31 N906H of Hawaiian Airlines collided on the ground with Vickers Viscount N7410 of Aloha Airlines at Honolulu International Airport. The Viscount was damaged beyond repair.[36]
On September 9, 1969, Allegheny Airlines Flight 853, a DC-9-30, collided in mid-air with a Piper PA-28 Cherokee near Fairland, Indiana. The DC-9 carried 78 passengers and 4 crew members, the Piper one pilot. The occupants of both aircraft were killed in the accident and the aircraft were destroyed.[37][38]
On February 15, 1970, a Dominicana de Aviación DC-9 crashed after taking off from Santo Domingo, in what is known as the Dominicana DC-9 air disaster. The crash, possibly caused by contaminated fuel, killed all 102 passengers and crew, including champion boxer Teo Cruz.[39][40]
On May 2, 1970, an Overseas National Airways DC-9, wet-leased to ALM Dutch Antilles Airlines and operating as ALM Flight 980, ditched in the Caribbean Sea on a flight from New York's John F. Kennedy International Airport to Princess Juliana International Airport on Sint Maarten. After three landing attempts in poor weather at Sint Maarten, the pilots began to divert to their alternate of Saint Croix, U.S. Virgin Islands but ran out of fuel 30 mi (48 km) short of the island. After about 10 minutes, the aircraft sank in 5,000 ft (1524 m) of water and was never recovered. 40 people survived the ditching, 23 perished.[41]
On November 14, 1970, Southern Airways Flight 932, a DC-9, crashed into a hill near Tri-State Airport in Huntington, West Virginia. All 75 on board were killed (including 37 members of the Marshall University Thundering Herd football team, eight members of the coaching staff, 25 boosters, and others).
On January 26, 1972, Jugoslovenski Aero Transport Flight 367, in flight from Stockholm to Belgrade, DC-9-32 registration YU-AHT, was destroyed in flight by a bomb placed on board. The sole survivor was a flight attendant, Vesna Vulovic, who holds the record for the world's longest fall without a parachute when she fell some 33,000 ft (10,000 m) inside the tail section of the airplane and survived.
On December 20, 1972, North Central Airlines Flight 575, DC-9-31 registration N954N, collided during its takeoff roll with Delta Air Lines Flight 954, a Convair CV-880 that was taxiing across the same runway at O'Hare International Airport in Chicago, Illinois, in what is known as the 1972 Chicago-O'Hare runway collision. The DC-9 was destroyed, killing 10 and injuring 15 of the 45 people on board; two people among the 93 aboard the Convair 880 suffered minor injuries.[42]
On July 31, 1973, Delta Air Lines Flight 723, DC-9-31 registration N975NE, crashed into a seawall at Logan International Airport in Boston, Massachusetts, killing all 83 passengers and 6 crew members on board. One of the passengers initially survived the accident but later died in a hospital.
On September 11, 1974, Eastern Air Lines Flight 212, a DC-9-30 crashed just short of the runway at Charlotte, North Carolina, killing 71 out of the 82 occupants.
On 30 October 1975, an Inex-Adria Aviopromet DC-9-32 hit high ground during an approach in fog near Prague-Suchdol, Czechoslovakia. 75 people were killed.[43]
On September 10, 1976, an Inex-Adria Aviopromet DC-9 collided with a British Airways Trident over the Croatian town of Vrbovec, killing all 176 people aboard both aircraft, in what is known as the 1976 Zagreb mid-air collision.
On April 4, 1977, Southern Airways Flight 242, a DC-9-31, lost engine power in a storm then crash landed onto a highway in New Hope, Georgia, US, striking road side buildings. The crash and fire resulted in the death of both flight crew and 61 passengers. Nine people on the ground also died. Both flight attendants and 20 passengers survived.[44][45]
On June 26, 1978, Air Canada Flight 189, a DC-9 overran the runway in Toronto after a blown tire aborted the takeoff. Two of the 107 passengers and crew were killed.[46]
On September 14, 1979, Aero Trasporti Italiani Flight 12, a DC-9-32 crashed in the mountains near Cagliari, Italy while approaching Cagliari-Elmas Airport. All 27 passengers and 4 crew members died in the crash and ensuing fire.[47]
An Itavia DC-9 (registration I-TIGI) which was lost in an accident at Ustica in 1980.
On June 27, 1980, Aerolinee Itavia Flight 870, a DC-9-15 suffered an in-flight explosion and crashed into the sea near the Italian island of Ustica. All 81 people on board were killed. The causes of this accident are still unclear.
Itavia DC-9 (I-TIGI) was destroyed in an accident at Ustica. Shown in the "Museo della Memoria" opened in Bologna in 2007.
On July 27, 1981, Aeromexico Flight 230 ran off the runway in Chihuahua. Bad weather and pilot error were blamed.
On June 2, 1983, Air Canada Flight 797, a DC-9 experienced an electrical fire in the aft lavatory during flight, resulting in an emergency landing at Cincinnati/Northern Kentucky International Airport. During evacuation, the sudden influx of oxygen caused a flash fire throughout the cabin, resulting in the deaths of 23 of the 41 passengers, including Canadian folk singer Stan Rogers. All five crew members survived.
On December 7, 1983, the Madrid Runway Disaster took place where a departing Iberia Boeing 727 struck an Aviaco Douglas DC-9 causing the death of 93 passengers and crew. All 42 passengers and crew on board the DC-9 were killed.
On August 31, 1986, Aeroméxico Flight 498 collided in mid-air with a Piper Cherokee over the city of Cerritos, California, then crashed into the city, killing all 67 aboard the aircraft, 15 people on the ground, and all 3 in the small plane.
On 4 April 1987, Garuda Indonesia Flight 035, a DC-9-32, hit a pylon and crashed on approach to Polonia International Airport in bad weather with 24 fatalities.[48]
On December 3, 1990, Northwest Airlines Flight 1482, a DC-9-14, went on the wrong taxiway in dense fog at Detroit-Metropolitan Wayne County Airport, Michigan (DTW). It entered the active runway instead of taxiway instructed by air traffic controllers. It collided with a departing Northwest Boeing 727. Nine people were killed.[49][50]
On July 2, 1994, USAir Flight 1016 crashed in Charlotte, North Carolina while performing a go-around because of heavy storms and wind shear at the approach of runway 18R. There were 37 fatalities and 15 injured among the passengers and crew. Although the airplane came to rest in a residential area with the tail section striking a house, there were no fatalities or injuries on the ground.
On May 11, 1996 ValuJet Flight 592 crashed in the Florida Everglades due to a fire caused by the activation of chemical oxygen generators illegally stored in the hold. The fire damaged the plane's electrical system and eventually overcame the crew, resulting in the deaths of 110 people.
On October 10, 1997, Austral Flight 2553, DC-9-32 registration LV-WEG, en route from Posadas to Buenos Aires, crashed near Fray Bentos, Uruguay, killing 74 people (69 passengers and 5 crew).[51]
On February 2, 1998, Cebu Pacific Flight 387 crashed on the slopes of Mount Sumagaya in Misamis Oriental, Philippines, killing all 104 people on board. Aviation investigators deemed the incident to be caused by pilot error when the plane made a non-regular stopover to Tacloban.
On November 9, 1999, TAESA Flight 725 crashed a few minutes after leaving the Uruapan Airport en route to Mexico City. 18 people were killed in the accident.[52]
On October 6, 2000, Aeroméxico Flight 250, a DC-9-31 en route from Mexico City to Reynosa, Mexico, could not stop at end of runway and crashed into houses and fell into a small canal. Four people on the ground were killed. None of 83 passengers and 5 crew members were killed. The DC-9 was heavily damaged and classified as a loss. The runway had seen heavy rainfall as a result of Hurricane Keith.[53]
On April 15, 2008, a Hewa Bora Airways DC-9 crashed into a residential neighborhood, in the Goma, Democratic Republic of the Congo,[54] resulting in the deaths of at least 44 people,[55] in what is known as the 2008 Goma DC-9 crash.
On July 6, 2008, USA Jet Flight 199, a DC-9-15F, after taking off from Shreveport, LA airport bound for Saltillo, Mexico crashed and burned. The captain was killed and first officer was seriously injured.[56] The cause of the crash is under investigation.
[edit]Aircraft on display
XA-TBX ex-Aerocaribe- Preserved at Venustiano Carranza at Benito Juarez International Airport as a public hi-tech library
ex-N8903E Northwest Airlines- Preserved at TVF since 15-04-1998 as a donation to the Northland Community & Technical College
ex-Air Canada C16Y70 preserved and on display at the Canada Aviation Museum
ex-Iberia Airways EC-BQZ-CY105 Preserved at MAD on display between terminals 1 and 2, used as theater by AENA
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The McDonnell Douglas DC-10 is a three-engine widebody jet airliner manufactured by McDonnell Douglas. The DC-10 has range for medium- to long-haul flights, capable of carrying a maximum 380 passengers. Its most distinguishing feature is the two turbofan engines mounted on underwing pylons and a third engine at the base of the vertical stabilizer. The model was a successor to McDonnell Douglas's DC-8 for long-range operations, and competed in the same markets as the Lockheed L-1011 Tristar, which has a similar layout to the DC-10.
Production of the DC-10 ended in 1989 with 386 delivered to airlines and 60 to the U.S. Air Force as air-to-air refueling tankers, designated the KC-10 Extender.[2] The largest operator of the DC-10 is U.S. cargo airline FedEx Express. The DC-10 was succeeded by the related McDonnell Douglas MD-11. Boeing, who merged with McDonnell Douglas in the 1990s, conducted an upgrade program for the DC-10s, equipping several with a glass cockpit, leading to the re-designation as MD-10s.
Development
Following an unsuccessful proposal for the U.S. Air Force's CX-HLS (Heavy Logistics System) in 1965, Douglas Aircraft began design studies based on its CX-HLS design. In 1966, American Airlines offered a specification to manufacturers for a widebody aircraft smaller than the Boeing 747 but capable of flying similar long-range routes from airports with shorter runways. The DC-10 became McDonnell Douglas's first commercial airliner after the merger between McDonnell Aircraft Corporation and Douglas Aircraft Company in 1967.[3] An early DC-10 design proposal was for a four-engined double deck wide-body jet airliner with a maximum seating capacity of 550 passengers similar in length of 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 similar in length to a DC-8 Super 60.[4]
British Caledonian DC-10-30 at London Gatwick Airport in 1988
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.[5][6] That year, the world's demand for commercial airliners was 724 aircraft.[7] The DC-10, a series 10 model, made its first flight on August 29, 1970.[8] Following a flight test program with 929 flights covering 1,551 hours, the DC-10 was awarded a type certificate from the FAA on July 29, 1971.[9] It entered commercial service with American Airlines on August 5, 1971 on a round trip flight between Los Angeles and Chicago. United Airlines began DC-10 service on August 16, 1971.[10] The DC-10's similarity to the L-1011 in terms of passenger capacity and launch in the same timeframe resulted in a head to head sales competition which affected profitability of the aircraft.
The first DC-10 version was the "domestic" series 10 with a range of 3,800 miles (3,300 nmi, 6,110 km) with a typical passenger load and a range of 2,710 miles (2,350 nmi, 4,360 km) with maximum payload. The series 15 had a typical load range of 4,350 miles (3,780 nmi, 7,000 km).[11][12] The series 20 was powered by Pratt & Whitney JT9D turbofan engines, whereas the series 10 and 30 engines were General Electric CF6. Before delivery of its aircraft, Northwest's president asked that the "series 20" aircraft be redesignated "series 40" because the aircraft was much improved over the original design. The FAA issued the series 40 certificate on October 27, 1972.[13]
A FedEx Express MD-10-10, a modernized DC-10-10
The series 30 and 40 were the longer range "international" versions. One of the main visible differences between 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 four gear (one front, three main). The center main two-wheel landing gear (which extends from the center of the fuselage) was added to accommodate the extra weight by distributing the weight and providing additional braking. The series 30 had a typical load range of 6,220 mi (10,010 km) and a maximum payload range of 4,604 mi (7,410 km). The series 40 had a typical load range of 5,750 miles (9,265 km) and a maximum payload range of 4,030 miles (3,500 nmi, 6,490 km).[11][14]
Eventually, the DC-10 was able to distinguish itself from its competitors with two engine options, as well as earlier introduction of longer range variants than the L-1011. The 446th and final DC-10 rolled off the production line in December 1988 and was delivered to Nigeria Airways in July 1989.[15] The DC-10 was assembled at McDonnell Douglas's Douglas Products Division in Long Beach, California.[2] As the final few DC-10 deliveries were occurring, McDonnell Douglas had already started production of the DC-10's successor, the MD-11.[16]
[edit]Design
Northwest Airlines DC-10-30 at London Gatwick Airport in 2003
The DC-10 is a low-wing cantilever monoplane, powered by three turbofan engines. Two 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. The vertical stabilizer, with its two-segment rudder, is mounted on top of the tail engine banjo. The horizontal stabilizer and its four-segment elevator, is attached to the sides of the rear fuselage in the conventional manner. The airliner has a 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.[17]
It was designed for medium to long-range flights that can accommodate 250 to 380 passengers, and is operated by a cockpit flight crew of three. The fuselage has underfloor stowage for cargo and baggage.[18]
[edit]Variants
DC-10-30 flight deck
[edit]Original variants
DC-10-10
The DC-10-10 is the initial passenger version, produced from 1970 to 1981. The DC-10-10 was equipped with GE CF6-6 engines, which was the first civil engine version the CF6 family. A total of 122 were built.[19]
DC-10-10CF
The -10CF is a convertible passenger and cargo transport version of the -10. Eight were built for Continental Airlines and one for United Airlines.[19]
DC-10-15
The -15 variant was designed for use at hot, high-altitude airports. The series 15 is basically a -10 fitted with higher-thrust GE CF6-50C2F (derated DC-10-30 engines) powerplants.[20] The -15 was first ordered in 1979 by Mexicana and Aeroméxico. Seven were completed between 1981 and 1983.[21]
[edit]Longer range variants
DC-10-20
A proposed version of the DC-10-10 with extra fuel tanks, 3-ft (0.9 m) extensions on each wingtip and a rear center landing gear. It was to use Pratt & Whitney JT9D-15 turbofan engines, each producing 45,500 lbf (203 kN) of thrust, with a maximum takeoff weight of 530,000 lb (240,400 kg). But engine improvements led to increased thrust and increased takeoff weight.[22] Northwest Orient Airlines, one of the launch customers for this longer range DC-10 requested the name change to DC-10-40.[23]
Interior of a DC-10-30 operated by Biman, the flag carrier of Bangladesh
DC-10-30
A long-range model and the most common model produced. It was built with General Electric CF6-50 turbofan engines and larger fuel tanks to increase range and fuel efficiency, as well as a set of rear center landing gear to support the increased weight. It was very popular with European flag carriers. A total of 163 were built from 1972 to 1988 and delivered to 38 different customers.[24] The model was introduced in service on November 30, 1972, with Swissair and KLM as its first customers.[citation needed]
DC-10-30CF
The convertible cargo/passenger transport version of the -30. The first deliveries were to Overseas National Airways and Trans International Airlines in 1973. A total of 27 were built.[19]
DC-10-30ER
The extended range version of the -30. The -30ER aircraft has a higher maximum takeoff weight of 580,000 lb (263,160 kg), are powered by three GE CF6-50C2B engines each producing 54,000 lbf (240 kN) of thrust and are equipped with an additional fuel tank in the rear cargo hold.[25] It has an additional 700 mi of range to 6,600 mi (5,730 nmi, 10,620 km. The first of this variant was delivered to Finnair in 1981. A total of six were built and five -30s were later converted to -30ERs.
DC-10-30AF
Also known as the DC-10-30F. This was the all freight version of the -30. Production was to start in 1979, but Alitalia did not confirm its order then. Production began in May 1984 after the first aircraft order from FedEx. A total of 10 were built.[26]
Japan Airlines DC-10-40
DC-10-40
The first long-range version fitted with Pratt & Whitney JT9D engines. Originally designated DC-10-20, this model was renamed DC-10-40 after a special request from Northwest Orient Airlines as the aircraft was much improved compared to its original design, with a higher MTOW (on par with the Series 30) and more powerful engines. The airline's president wanted to advertise he had the latest version.[23][27] The company also wanted their aircraft to be equipped with the same engines as their Boeing 747s for commonality.[28] Northwest Orient Airlines and Japan Airlines were the only airlines to order the series 40 with 22 and 20 aircraft, respectively. Engine improvements led to the DC-10-40s delivered to Northwest featuring Pratt & Whitney JT9D-20 engines producing 50,000 lbf (222 kN) of thrust and a MTOW of 555,000 lb (251,815 kg). The -40s for Japan Airlines were equipped with P&W JT9D-59A engines that produced a thrust of 53,000 lbf (235.8 kN) and a MTOW of 565,000 lb (256,350 kg).[22] 42 were built from 1973 to 1983.[29]
DC-10-50
A proposed version with Rolls-Royce RB211-524 engines for British Airways. The order never came and the plans for the DC-10-50 were abandoned.[30]
DC-10 "Twin"
A proposed DC-10 version with two CF-6 engines, likely designed to compete against the Airbus A300.[citation needed]
[edit]Tanker versions
A USAF KC-10 Extender during refueling
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.[31]
The KDC-10 is an aerial refueling tanker for 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 two KDC-10 tankers for lease. Four have been built.[32][33]
The 10 Tanker Air Carrier DC-10-10 during a water drop demonstration
The 10 Tanker Air Carrier is a DC-10-10 converted into a firefighting tanker aircraft, using modified water tanks from Erickson Air-Crane.
[edit]MD-10 upgrade
The MD-10 is retrofit cockpit upgrade to the DC-10 and a re-designation to MD-10. The upgrade included an Advanced Common Flightdeck (ACF) used on the MD-11.[34] The new cockpit eliminated the need for the flight engineer position and allowed common type rating with the MD-11. This allows companies such as FedEx Express, which operate both the MD-10 and MD-11, to have 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 the conversions.[35]
[edit]Operators
DC-10-30 of Biman Bangladesh, one of the two remaining passenger airlines that operate the jetliner, with landing gear extended on final approach to London Heathrow, 2003
See also: List of McDonnell Douglas DC-10 operators
On January 8, 2007, Northwest Airlines retired its last remaining DC-10 from scheduled passenger service, replacing it with an Airbus A330 for a route between Minneapolis-St. Paul and Honolulu,[36] 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."[37] "The DC-10 is going to be remembered as a better cargo plane than passenger plane," said Richard Aboulafia, an analyst with the Teal Group.[37] In November 2006 ATA Airlines announced that they had purchased seven of Northwest's remaining DC-10s to replace their Lockheed L-1011s. Omni Air International purchased six of Northwest's DC-10 aircraft.[38]
The aging models are now largely used as dedicated freight aircraft. American Airlines and United Airlines sold their large DC-10-10 fleets to cargo carrier FedEx. Many have been modernized to MD-10s by adding a glass cockpit, which eliminates the need for a flight engineer. Other DC-10 aircraft continue in charter and cargo services with their three-person flight deck configuration. Omni Air International and World Airways continue to operate the DC-10 on charter passenger services as well as for the Air Mobility Command. Biman Bangladesh Airlines operates five DC-10-30s as one of their primary passenger aircraft as of 2009.[39]
The Orbis DC-10 Flying Eye Hospital, February 2009
Non-airline operators include the Royal Netherlands Air Force with three DC-10-30CF-based KDC-10 tanker aircraft, the USAF with its 59 KC-10s, and the 10 Tanker Air Carrier with its modified DC-10-10 used for fighting wildfires.[40] Orbis International has used a single DC-10-10 converted into a flying eye hospital. Surgery is performed on the ground and the operating room is located between the wings for maximum stability.[41] Orbis chose to replace its aging DC-10 with a MD-10,[42] that was converted from a DC-10 jointly donated by FedEx and United Airlines.[43] The MD-10 eye hospital is expected to be flying in 2010.[43][44] Additionally, one former American Airlines DC-10-10 is operated by the Missile Defense Agency as the Widebody Airborne Sensor Platform (WASP).[45]
In January 2011, there were 97 DC-10s in service with commercial operators FedEx Express (74), Biman Bangladesh Airlines (4), Kelowna Flightcraft Air Charter (3), and others with fewer aircraft.[46][47] [48]
[edit]Incidents and accidents
As of January 2012, the DC-10 was involved in 56 aviation occurrences,[49] including 32 hull-loss accidents,[50] with 1,262 occupant fatalities.[51] It has been involved in nine hijackings and criminal events resulting in 171 occupant fatalities.[51] Despite its troubled beginnings in the 1970s, which gave it an unfavorable reputation,[52] the DC-10 has proved a reliable aircraft.[53] The DC-10's initially poor safety record continuously improved as design flaws were rectified and fleet hours increased.[53] The DC-10's lifetime safety record is comparable to similar second-generation passenger jets as of 2008.[54]
[edit]Cargo door problem
The DC-10 was designed with cargo doors that opened outward instead of conventional inward-opening "plug-type" doors. Using outward-opening doors allowed the DC-10's cargo area to be completely filled since the door was not occupying usable space. To secure the door against the outward force from the 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 great potential for explosive decompression.[55]
[edit]American Airlines Flight 96
A problem with the outward-opening cargo door first became publicly known on June 12, 1972, when American Airlines Flight 96 lost its aft cargo door shortly after takeoff from Detroit Metro Airport. Before Flight 96 took off, an airport employee had forced the door shut, which, due to the cargo door's design, gave an outward appearance of being securely locked despite the internal locking mechanism's not being fully engaged. Subsequently, when the plane reached approximately 11,750 feet (3,580 m) in altitude, the cargo door blew out, causing an explosive decompression which partially collapsed the cabin floor at the rear of the plane. This collapsed section of the floor cut or impeded many of the control cables to the empennage control systems necessary to fly the plane.[56][57] The crew was able to accomplish an emergency landing by using the ailerons, right elevator, some limited rudder trim and asymmetrical thrust of the wing engines.[58]
During the investigation of the near-crash of Flight 96, U.S. National Transportation Safety Board (NTSB) investigators found that the DC-10's cargo door design was dangerously flawed. The door relied on a set of heavy steel hooks to secure it against the door frame. When the hooks were fully engaged, an outside lever on the cargo door could be depressed, which drives a set of locking pins through the hooks, holding them in place. The NTSB investigation found that it was possible to close the outside lever without the hooks being fully engaged, and there would be no outward signs that the locking mechanism was not engaged. Even though the hooks and locking pins were not in the closed position, the cargo door indicator in the cockpit would still register the door as being secured. This combination of factors caused Flight 96 to take off without its aft cargo door being fully locked. And when the door blew out at altitude, the sudden decompression of the airplane caused a large pressure difference to build up between the cabin above and the cargo bay below. This depressurization loading is what caused the cabin floor to collapse.[59] And because the DC-10 was designed with its hydraulics and control wires routed through the floor beams, the collapse of the cabin floor caused a loss of vital flight controls.[56]
FedEx became the first U.S. carrier to equip its aircraft with an anti-missile defense system in 2006. The gray oval Northrop Grumman Guardian pod can be seen on the belly of this FedEx MD-10 between and just aft of the main landing gear.
Following the Windsor incident investigation, the NTSB made several recommendations, including repairing the faulty cargo door design to make it impossible for baggage handlers to close the cargo door lever without the locking pins being fully engaged. It was also recommended that vents be installed in the cabin floor so that, in case of an explosive decompression, the pressure difference between the cabin and cargo bay could quickly be equalized without collapsing the cabin floor and damaging critical control systems.[59] Although many carriers voluntarily modified the cargo doors, no airworthiness directive was issued to require reworking of the locking system, due to a gentlemen's agreement between the head of the FAA and McDonnell Douglas. McDonnell Douglas did make modifications to the cargo door, but the basic design remained unchanged and problems persisted.[59]
[edit]Turkish Airlines Flight 981
On March 3, 1974, an almost identical cargo door blow-out caused Turkish Airlines Flight 981 to crash into a forest near the town of Ermenonville, France shortly after leaving Paris.[59] All 346 people were killed[60] in one of the deadliest air crashes of all time.[61] Circumstances of this crash were very similar to the previous accident. The cargo door had not been fully locked, though it appeared so to both cockpit crew and ground personnel. The Turkish aircraft had a different seating configuration that exacerbated the effects of decompression, which caused the aircraft's floor to collapse into the cargo bay. Control cables running through the floor of the plane were severed when the floor collapsed and this rendered the aircraft uncontrollable.[59] Crash 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.[60] Following this crash, a special subcommittee of the House of Representatives investigated the cargo door issue and the FAA's certification of the original design.[62] An airworthiness directive was issued, and all DC-10s underwent mandatory door modifications.[62] The DC-10 experienced no more major incidents related to its cargo door after FAA-approved changes were made.[59]
[edit]American Airlines Flight 191
The DC-10 experienced another major accident with the crash of American Airlines Flight 191 on May 25, 1979. Flight 191 lost its number one (left wing) engine after taking off from O'Hare International Airport in Chicago, USA.[63] As the engine separated upwards, it ripped through the leading edge of the wing, rupturing hydraulic lines. Without hydraulic pressure, the left wing leading edge slats retracted due to the force of the air moving over the wings. That, in turn, increased the stall speed of the left wing above the engine failure climb out speed being used by the pilots. When the left wing stalled, the aircraft rapidly rolled to the left and crashed before the flight crew could recover. All 271 people on board, plus two on the ground, were killed.[64]
The United States National Transportation Safety Board (NTSB) officials discovered that a maintenance procedure was the culprit. American Airlines mechanics removed the engine and its pylon together, rather than removing the engine from the pylon then the pylon from the wing, as recommended by McDonnell Douglas. This was done using a forklift and the pylon was inadvertently cracked in the process. The short-cut procedure, believed to save many man hours on maintenance, was used by three major airlines, although McDonnell Douglas advised against it.[65] In November 1979, the Federal Aviation Administration (FAA) fined American Airlines $500,000 for using this faulty maintenance procedure. Continental Airlines was fined $100,000 on a similar charge.[65][66]
The Chicago accident also highlighted a major deficiency in the DC-10 design; its lack of a locking mechanism to maintain the position of the leading-edge slats in the event of a hydraulic or pneumatic failure.[65] Other wide-body aircraft of the day carried such a feature. When the engine pulled up and over the wing, it tore out electrical wiring in the wing, thus rendering vital warning instruments in the cockpit inoperable. Following the Chicago crash, the FAA withdrew the DC-10's type certificate on June 6, 1979, which grounded U.S. DC-10s. It also barred all DC-10s from U.S. airspace. These measures were rescinded on July 13 after modifications were made to the slat actuation and position systems, along with stall warning and power supply changes.[67][65]
[edit]United Airlines Flight 232
Another major DC-10 crash was United Airlines Flight 232 disaster at Sioux City, Iowa, USA, on July 19, 1989. The number two (tail) engine suffered an uncontained fan disk failure in flight, which damaged all three hydraulic systems and rendered the hydraulic flight controls inoperable. The flight crew, led by Captain Al Haynes and assisted by a senior pilot flying as a passenger (Dennis E. "Denny" Fitch), performed an emergency landing by constantly adjusting the thrust of the remaining two engines. The crew managed to fly the aircraft onto the runway in a partially controlled manner, and 185 of the 296 people on board survived in spite of the destruction of the plane during that landing.[68]
The DC-10 included no cable backup for the hydraulic powered flight controls because it was considered nearly impossible for three hydraulic systems to fail during one flight, and furthermore the control surfaces are too large to be moved without hydraulic assistance. However, all three hydraulic systems were in close proximity, directly beneath the tail engine. The #2 engine explosion hurled shrapnel that ruptured all three lines, resulting in total loss of control to the elevators, ailerons, spoilers, horizontal stabilizer, rudder, flaps and slats.[68]
Following the UAL 232 accident, hydraulic fuses were installed in the #3 hydraulic system in the area below the #2 engine on all DC-10 aircraft to ensure that sufficient control capability remained if all three hydraulic system lines should be damaged in the tail area. It is still possible to lose all three hydraulic systems elsewhere. That nearly occurred to a cargo airliner in 2002 during takeoff, when a main gear tire exploded in the wheel well. The damage in the left wing area caused total loss of pressure in the #1 and the #2 hydraulic systems. The #3 system was dented but not penetrated.[69]
[edit]Other notable accidents and incidents
Other notable incidents and accidents involving the DC-10 are listed below.
November 3, 1973 - National Airlines Flight 27, a DC-10-10 experienced an uncontained failure of the right (#3) engine. The cabin was penetrated by shrapnel from the engine and lost pressure. One passenger was killed. The crew initiated an emergency descent, and landed the aircraft safely.
October 31, 1979 - Western Airlines Flight 2605, a DC-10-10 crashed while landing at Mexico City International Airport. 72 out of 88 people died.
November 28, 1979 - Air New Zealand Flight 901, DC-10-30 ZK-NZP crashed into Mount Erebus on Ross Island, Antarctica during a sightseeing flight over the continent, killing all 257 on board. The accident was caused by the flight coordinates being altered without the flight crew's knowledge, combined with unique Antarctic weather conditions.
January 23, 1982 - World Airways Flight 30, a DC-10-30CF, registration N113WA, overran the runway at Boston Logan International Airport. All 12 crew survived, but two of the 200 passengers were never found and assumed dead.[70]
September 13, 1982 – Spantax Flight BX995, DC-10-30CF EC-DEG was destroyed by fire after an aborted take-off at Málaga, Spain. 50 passengers were killed and 110 passengers were injured due to the flames.
December 23, 1983 – Korean Air Cargo Flight 084, DC-10-30CF HL7339 was destroyed after colliding head-on with a Piper PA-31 Navajo while taxiing at Anchorage, Alaska. All on board both aircraft survived.
July 27, 1989 – Korean Air Flight 803, DC-10-30, registration HL7328 crashed short of the runway in bad weather while trying to land at Tripoli, Libya. A total of 75 of the 199 on board plus another four people on the ground were killed in the accident.[71]
September 19, 1989 – UTA Flight 772, DC-10-30 N54629, crashed in Ténéré Desert following an in-flight bomb explosion, claiming the lives of all on board.
December 21, 1992 – Martinair Flight 495, DC-10-30CF PH-MBN crashed while landing in bad weather at Faro, Portugal.
April 7, 1994 - FedEx Flight 705, DC-10-30 N306FE experienced an attempted hijacking. FedEx employee Auburn Calloway tried to hijack the plane, but the crew fought him off and returned to Memphis.
June 13, 1996 – Garuda Indonesia Flight 865, DC-10-30 PK-GIE had just taken off from Fukuoka Airport, Japan when a high-pressure blade from engine #3 separated. The aircraft was just a few feet above the runway and the pilot decided to abort the take-off. Consequently, the DC-10 skidded off the runway and came to a halt 1,600 ft (490 m) past it, having lost one of its engines and its landing gear.
January 31, 2001 - Japan Airlines Flight 958, bound for Narita International Airport from Gimhae International Airport, nearly collided with another Japan Airlines aircraft. The other aircraft, a Boeing 747, dived and avoided the Narita-bound DC-10.
December 25, 2000 - Hawaiian Airlines Flight 481, from Honolulu to Tahiti, Faaa International Airport, overshot the runway in a driving rain storm and stopped with its front wheel in a lagoon.[72]
The Air France Concorde crash of 2000 was attributed to a fragment of titanium that fell from the thrust reverser of a Continental Airlines DC-10 that had taken off four minutes earlier. This fragment was traced to a third party parts replacement that had not been approved by the FAA.
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The McDonnell Douglas DC-9-10/20/30
Country of origin
United States of America
Photos
Powerplants
10 - Two 54.5kN (12,250lb) Pratt & Whitney JT8D-5 turbofans.
30 - Two 64.5kN (14,500lb) JT8D-9s, or two 66.7kN (15,000lb) JT8D-11s, or two 71.2kN (16,000lb) JT8D-17s.
Performance
10 - Max cruising speed 903km/h (488kt), economical cruising speed 885km/h (478kt). Range with max payload 1055km (570nm).
30 - Max cruising speed 907km/h (490kt), long range cruise 798km/h (430kt). Range at high speed cruise with 64 passengers and reserves 2150km (1160nm), range at long range cruise with 80 passengers and reserves 3095km (1670nm).
Weights
10 - Operating empty 22,635kg (49,900lb), max takeoff 41,140kg (90,700lb).
30 - Empty 25,940kg (57,190lb), max takeoff 54,885kg (121,000lb).
Dimensions
10 - Wing span 27.25m (89ft 5in), length 31.82m (104ft 5in), height 8.38m (27ft 6in). Wing area 86.8m2 (934sq ft).
30 - Same except for length 36.37m (119ft 4in), wing span 28.47m (93ft 5in). Wing area 93.0m2 (1000.7sq ft).
Capacity
Flightcrew of two.
10 - Seating for 80 in a single class at five abreast and 86cm (34in) pitch. Max seating for 90.
30 - Max seating for 115 in a single class, five abreast and 81cm (32in) pitch, standard single class seating for 105.
30CF - can carry over eight cargo pallets.
Production
976 DC-9s of all models built including 137 -10s, 10 -20s and 662 -30s (including military C-9s). 97 DC-9-10s, 4 DC-9-20s and 381 DC-9-30s in airline service at late 2002. 9 DC-9-10s and 3 DC-9-30s used as corporate jets at late 2002.
Type
Short range airliners
History
No other airliner in history has undergone more development than the prolific DC-9/MD-80/MD-90/717 series, which started life with the 70 seat DC-9-10 of the early sixties.
Douglas developed the DC-9 as a short range airliner complementing the much larger DC-8. Development was launched on April 8 1963, with a launch order from Delta following soon after. The DC-9 was an all new design, featuring rear fuselage mounted engines, a T-tail, moderately swept wings and seats for up to 90 passengers in a five abreast fuselage.
Construction of the prototype began in July 1963 and the first flight occurred on February 25 1965. Certification and service entry was on November 23 and December 8 1965, respectively.
From the outset the DC-9 had been designed with stretched larger capacity developments in mind. The first stretch resulted in the biggest selling DC-9, the 4.54m (14ft 11in) longer, 105 seat DC-9-30, which entered service with Eastern on February 1 1967. Subsequent stretched versions are described separately.
Small numbers of developed versions of the DC-9-10 were also built. The DC-9-20 featured the DC-9-10's fuselage with the 30's more powerful engines and longer span wings, giving better hot and high performance. The DC-9-15 was basically a -10 but with more fuel and higher weights. Factory built convertibles and pure freighters were also offered, while a number of DC-9-30s have been converted to freighters, and/or are having Stage 3 hushkits fitted, further extending their useful service lives.
The DC-9 was followed in subsequent modified forms by the MD-80, MD-90 and Boeing 717. With the final two deliveries of the 717 in 2006, production of the DC-9/MD-80/90/717 aircraft family ceased after 41 years and over 2,400 units built.
Origins
During the 1950s Douglas Aircraft studied a short-medium range airliner to complement its higher capacity, long range DC-8. (DC stands for Douglas Commercial.[1]) A medium range four-engine Model 2067 was studied but did not receive enough interest from airlines and was abandoned. In 1960 Douglas signed a two-year contract with Sud Aviation for technical cooperation. Douglas would market and support the Sud Aviation Caravelle and produce a licensed version if airlines ordered large numbers, but none were ordered and Douglas returned to its design studies after the two years.[2]
Northwest Airlines (NWA) DC-9 T-tail at Regina International Airport
In 1962 design studies were underway. The first version seated 63 passengers and had a gross weight of 69,000 lb (31,300 kg). This design was changed into what would be initial DC-9 variant.[2] Douglas gave approval to produce the DC-9 on April 8, 1963.[2] Unlike the competing but larger Boeing 727 trijet, which used as many 707 components as possible, the DC-9 was an all-new design. The DC-9 has two rear fuselage-mounted Pratt & Whitney JT8D turbofan engines, relatively small, efficient wings, and a T-tail.[3] The DC-9's takeoff weight was limited to 80,000 lb (36,300 kg) for a two-person flight crew by Federal Aviation Agency regulations at the time.[2] DC-9 aircraft have 5 seats across for economy seating. The airplane seats 80 to 135 passengers depending on version and seating arrangement.
The DC-9 was designed for short to medium routes, often to smaller airports with shorter runways and less ground infrastructure than the major airports being served by larger designs like the 707 and DC-8. Consequently, accessibility and short field characteristics were called for. The tail mounted engine design facilitated a clean wing design without engine pods, which had numerous advantages. flaps could be longer, unimpeded by pods on the leading edge and engine blast concerns on the trailing edge. This simplified design, improved airflow at low speeds and enabled lower takeoff and approach speeds, thus lowering field length requirements and keeping wing structure light. The second advantage of the tail-mounted engines was the reduction in foreign object damage from ingested debris from runways and aprons. Third, the absence of engines in underslung pods allowed a reduction in ground clearance, making the aircraft more accessible to baggage handlers and passengers. Turnarounds were simplified by built-in airstairs, including one in the tail, which shortened boarding and deplaning times. The problem of deep stalling, revealed by the loss of the BAC One-Eleven prototype in 1963, was overcome through various changes, including the introduction of vortilons, small surfaces beneath the wing's leading edge used to control airflow and increase low speed lift.[4]
[edit]Into production
C-9 Nightingale used for Aeromedical Evacuation
The first DC-9, a production model, flew on February 25, 1965.[5] The second DC-9 flew a few weeks later,[3] with a test fleet of five aircraft flying by July. This allowed the initial Series 10 to gain airworthiness certification on November 23, 1965 and to enter service with Delta Air Lines on December 8.[5] The DC-9 was always intended to be available in multiple versions to suit customer requirements,[6] and the first stretched version, the Series 30, with a longer fuselage and extended wing tips, flew on August 1, 1966, entering service with Eastern Air Lines in 1967.[5] The initial Series 10 would be followed by the improved -20, -30, and -40 variants. The final DC-9 series was the -50, which first flew in 1974.[3]
In 1967, the US Air Force selected the DC-9 to meet their requirement for an medical evacuation (MedEvac) and passenger transport aircraft, designated as the C-9A Nightingale; deliveries began in 1968.[7] The U.S. Navy also ordered five C-9Bs for passenger and cargo duties in April 1972.[7] The C-9B aircraft have provided air logistics support for the Navy and Marine Corps. A C-9B was also chosen by NASA for reduced gravity research.[8] Some C-9s were converted from former civilian DC-9s; three were also specially configured for VIP transport duties.[9] Kuwait also operated a small C-9 fleet.[9] All USAF C-9s were retired by 2005.[10]
A Cebu Pacific DC-9 in 2006
The DC-9 was a commercial success with 976 built when the production ended in 1982.[3] The DC-9 is one of the longest lasting aircraft in operation. Its reliability and efficiency led to sales of its successors into the 21st century.[citation needed] The DC-9 family is one of the most successful jet airliners with a total of over 2,400 units produced; it ranks third behind the second place Airbus A320 family with over 5,000 produced, and the first place Boeing 737 with over 7,000 produced.
Studies aimed at further improving DC-9 fuel efficiency, by means of retrofitted wingtips of various types, were undertaken by McDonnell Douglas. However these did not succeed in demonstrating significant benefits, especially with existing fleets shrinking. The wing design makes retrofitting difficult.[11]
[edit]Legacy
The DC-9 was followed by the introduction of the MD-80 series in 1980. The MD-80 series was originally called DC-9-80 series. It was a lengthened DC-9-50 with a higher maximum takeoff weight (MTOW), a larger wing, new main landing gear, and higher fuel capacity. The MD-80 series features a number of variants of the Pratt & Whitney JT8D turbofan engine having higher thrust ratings than those available on the DC-9.
The MD-80 series was further developed into the McDonnell Douglas MD-90 in the early 1990s. It has yet another fuselage stretch, a glass cockpit (first introduced on the MD-88) and completely new International Aero V2500 high-bypass turbofan engines. In comparison to the very successful MD-80, relatively few MD-90 examples were built.
The final variant of the DC-9 family was the MD-95, which was renamed the Boeing 717-200 after McDonnell Douglas's merger with Boeing in 1997 and before aircraft deliveries began. The fuselage length and wing are highly similar to those found on DC-9-30 aircraft, but much use was made of lighter, modern materials. Power is supplied by two BMW/Rolls-Royce BR715 high bypass turbofan engines.
China's Comac ARJ21 is derived from the DC-9 family. The ARJ21 is built with manufacturing tooling from the MD-90 Trunkliner program. Consequently it has the same fuselage cross section, nose profile, and tail.[12]
[edit]Variants
British Midland Airways DC-9-15
[edit]Series 10
The original DC-9 (later designated the Series 10) was the smallest DC-9 series. The -10 was 104.4 ft (31.8 m) long and had a maximum weight of 82,000 lb (37,000 kg). The Series 10 was similar in size and configuration to the BAC One-Eleven and featured a T-tail and rear mounted engines. Power was a pair of 12,500 lbf (56 kN) Pratt & Whitney JT8D-5 or 14,000 lbf (62 kN) JT8D-7 engines. A total of 137 were built. Delta Air Lines was the initial operator.
The Series 10 was produced in two main subvariants, the Series 14 and 15, although of the first four aircraft, three were built as Series 11s and one as Series 12. These were later converted to Series 14 standard. No Series 13 was produced. A passenger/cargo version of the aircraft with a 136 x 81 in side cargo door forward of the wing and a reinforced cabin floor, was certificated on March 1, 1967. Cargo versions included the Series 15MC (Minimum Change) with folding seats which can be carried at the rear of the aircraft, and the Series 15RC (Rapid Change) with seats removable on pallets. These differences disappeared over the years as new interiors have been installed.[13][14]
The Series 10 was unique in the DC-9 family in not having leading edge slats. The Series 10 was designed to have short takeoff and landing distances without the use of leading edge high-lift devices. Therefore, the wing design of the Series 10 featured airfoils with extremely high maximum lift capability in order to obtain the stalling speeds necessary for short field performance.[15]
[edit]Series 10 features
The Series 10 has an overall length of 104.4 feet (31.82 m), a fuselage length of 92.1 feet (28.07 m), a passenger cabin length of 60 feet (18.29 m), and a wingspan of 89.4 feet (27.25 m).
The Series 10 was offered with the 14,000 lbf (62 kN) thrust JT8D-1 and JT8D-7.[13][14]
All versions of the DC-9 are equipped with an AlliedSignal (Garrett) GTCP85 APU as standard which is located in the aft fuselage.[13][14]
The Series 14 was originally certificated at an MTOW of 85,700 lb (38,900 kg) but subsequent options offer increases to 86,300 and 90,700 lb (41,100 kg). The aircraft's MLW in all cases is 81,700 lb (37,100 kg). The Series 14 has a fuel capacity of 3,693 US gallons (with the 907 US gal centre section fuel). The Series 15, certificated on January 21, 1966, is physically identical to the Series 14 but has the increased MTOW of 90,700 lb (41,100 kg). Typical range with 50 passengers and baggage is 950 nmi (1,760 km), increasing to 1,278 nmi (2,367 km) at long range cruise. Range with maximum payload is 600 nmi (1,100 km), increasing to 1,450 nmi (2,690 km) with full fuel.[13][14]
The DC-9 Series 10, as with all later versions of the DC-9 is equipped with a two crew analog flightdeck.[13][14]
The aircraft is fitted with a passenger door in the port forward fuselage, and a service door/emergency exit is installed opposite. An airstair installed below the front passenger door was available as an option as was an airstair in the tailcone. This also doubled as an emergency exit. Available with either two or four overwing exits, the DC-9-10 can seat up to a maximum certified exit limit of 109 passengers. Typical all economy layout is 90 passengers, and 72 passengers in a more typical mixed-class layout with 12 first and 60 economy-class passengers.[13][14]
All versions of the DC-9 are equipped with a tricycle undercarriage, featuring a twin nose unit and twin main units.[13][14]
[edit]Series 20
Scandinavian Airlines DC-9-21
The Series 20 was designed to satisfy a Scandinavian Airlines request for improved short field performance by using the more powerful engines and improved wings of the -30 combined with the shorter fuselage used in the -10. Ten Series 20 aircraft were produced, all of them Model -21.[16]
In 1969, a DC-9 Series 20 at Long Beach was fitted with an Elliott Flight Automation Head-up display by McDonnell Douglas and used for successful three month-long trials with pilots from various airlines, the Federal Aviation Administration, and the US Air Force.[17]
[edit]Series 20 features
The Series 20 has an overall length of 104.4 feet (31.82 m), a fuselage length of 92.1 feet (28.07 m), a passenger cabin length of 60 feet (18.29 m), and a wingspan of 93.3 feet (28.44 m).[13][14]
The DC-9 Series 20 is powered by the 15,000 lbf (67 kN) thrust JT8D-11 engine.[13][14]
The Series 20 was originally certificated at an MTOW of 94,500 lb (42,900 kg) but this has been increased to 98,000 lb (44,000 kg), some 8% up on the higher weight Series 14s and 15s. The aircraft's MLW is 95,300 lb (43,200 kg) and MZFW is 84,000 lb (38,000 kg). Typical range with maximum payload is 1,000 nmi (1,900 km), increasing to 1,450 nmi (2,690 km) with maximum fuel. The Series 20, using the same wing as the Series 30 and indeed the Series 40 and 50, has a slightly lower basic fuel capacity than the Series 10 (3,679 US gallons).[13][14]
[edit]Series 20 milestones
First flight: September 18, 1968.
FAA certification: November 25, 1968.
First delivery: December 11, 1968 to SAS
Entry into service: January 27, 1969 with SAS.
Last delivery: May 1, 1969 to SAS.
[edit]Series 30
Ex-Spirit Airlines DC-9-30 Firebird II, highly modified as a surveillance aircraft for the U.S. Navy, based at Mojave Airport
The -30 was the definitive series, produced to counter Boeing's 737 twinjet, with 662 produced, accounting for about 60% of production. The -30 entered service with Eastern Airlines in February 1967 with a 14 ft 9 in (4.50 m) fuselage stretch, wingspan increased by just over 3 ft (0.9 m) and full-span leading edge slats, improving takeoff and landing performance. Gross take-off weight was typically 110,000 lb (50,000 kg). Engine options for Models -31, -32, -33 and -34 included the P&W JT8D-7 and JT8D-9 rated at 14,500 lbf (64 kN) of thrust, or JT8D-11 rated at 15,000 lbf (67 kN) of thrust.
The Series 30 was designed to incorporate extremely effective leading edge devices in order to reduce the landing approach speeds exhibited by the Series 10, at substantially higher maximum landing weights. The addition of full-span leading edge slats reduced approach speeds by 6 knots, despite the gross weight being 5000 lbs greater. The full span slats offered a significant weight advantage over slotted Krueger flaps, since the wing leading edge structure associated with the slat is a more efficient torque box than the structure associated with the slotted Krueger. The wing also had a 6% increase in wing chord, all ahead of the front spar. This increase in wing chord allowed the 15% chord slat to be incorporated.[18]
[edit]Series 30 subvariants
TAA DC-9-30 at Melbourne Airport, 1987
The Series 30 was produced in four main sub-variants.[13][14]
DC-9-31: Produced in passenger version only. The first DC-9 Series 30 flew on August 1, 1966, and the first delivery was made to Eastern Airlines on February 27, 1967 following certification on December 19, 1966. Basic MTOW of 98,000 lb (44,000 kg) and subsequently certificated at various increased weights up to 108,000 lb (49,000 kg).
DC-9-32: Introduced in the first year of production (1967). Certificated March 1, 1967. Basic MTOW of 108,000 lb (49,000 kg) and subsequently increased to 110,000 lb (50,000 kg). A number of cargo versions of the Series 32 were also produced including:
32LWF (Light Weight Freight) with modified cabin but no cargo door or reinforced floor, intended for package freighter use.
32CF (Convertible Freighter), with a reinforced floor but retaining passenger facilities
32AF (All Freight), a windowless all-cargo aircraft.
DC-9-33: Following the Series 31 and 32 came the Series 33, intended for passenger/cargo or all-cargo use. Certificated on April 15, 1968, the aircraft's MTOW was increased to 114,000 lb (52,000 kg), MLW to 102,000 lb (46,000 kg) and MZFW to 95,500 lb (43,300 kg). JT8D-9 or -11 (15,000 lbf (67 kN) thrust) engines were used. In addition, the wing incidence was increased 1.25 degrees, to reduce cruise drag.[19] Only 22 were built, as All Freight (AF), Convertible Freight (CF) and Rapid Change (RC) aircraft.
DC-9-34: The last version of the aircraft to be developed was the Series 34, intended for use on longer range routes with an MTOW of 121,000 lb (55,000 kg), an MLW of 110,000 lb (50,000 kg) and an MZFW of 98,000 lb (44,000 kg). The DC-9-34CF (Convertible Freighter) was certificated April 20, 1976, while the passenger followed on November 3, 1976. The aircraft is equipped with the more powerful JT8D-9s with the -15 and -17 engines as an option. It also included the wing incidence change introduced on the DC-9-33. Twelve were built, five as convertible freighters.
[edit]Series 30 features
The DC-9-30 was offered with a selection of variants of JT8D including the -1, -7, -9, -11, -15 and -17. The most common on the Series 31 is the JT8D-7 (14,000 lbf (62 kN) thrust), although it was also available with the -9 and -17 engines. On the Series 32 the JT8D-9 (14,500 lbf (64 kN) thrust) was standard, with the -11 also offered. The Series 33 was offered with the JT8D-9 or -11 (15,000 lbf (67 kN) thrust) engines and the heavyweight -34 with the JT8D-9, -15 (15,000 lbf (67 kN) thrust) or -17 (16,000 lbf (71 kN) thrust) engines.[13][14]
[edit]Series 40
DC-9-40 flight deck
This further lengthened version entered service with SAS in March 1968. With a 6 ft 6 in (2 m) longer fuselage, accommodation was up to 125 passengers. The -40 was fitted with Pratt & Whitney engines of between 14,500 and 16,000 lbf (64 and 71 kN). A total of 71 were produced.
[edit]Series 50
The -50 was the largest DC-9 to fly. It features an 8 ft 2 in (2.49 m) fuselage stretch and seats up to 139 passengers. It started revenue service in August 1975 with Eastern Airlines and included a number of detail improvements, a new cabin interior, and more powerful JT8D-15 or -17 engines in the 16,000 and 16,500 lbf (71 and 73 kN) class. McDonnell Douglas delivered 96, all as Model -51. Some visual cues to distinguish this version from other DC-9 variants include side strakes (fins) below the side cockpit windows and thrust reversers rotated about 22 degrees on the original configuration. However various maintenance replacements have seen the thrust reversers in the same position as the -30 and -40.
For later DC-9 variants, see McDonnell Douglas MD-80, McDonnell Douglas MD-90, and Boeing 717.
Delta DC-9-51 Interior Cabin View N779NC
[edit]Military and government
A US Air Force C-9A Nightingale
C-9A Nightingale - 23 aeromedical evacuation aircraft for the United States Air Force received from 1968.[9] The final active-duty flight of the C-9A was in September 2005.[20] The last C-9A was flown to Andrews AFB Museum in September 2012.[21][verification needed]
C-9B Skytrain II - 24 convertible passenger/transport versions for the United States Navy and Marine Corps delivered from 1973 to 1976. An additional five C-9s were converted from passenger configured DC-9s.[9]
VC-9C - 3 executive transport aircraft for the United States Air Force.[9] The three aircraft were delivered to the US Air Force in late 1976.
C-9K - 2 DC-9-30C for the Kuwait Air Force.[9]
[edit]Operators
Two British Midland DC-9s at Teesside Airport in 1994.
Perris Valley Skydiving DC-9-21, January 2008
A total of 129 DC-9 aircraft (all variants) were in commercial service as of November 2011, including Delta Air Lines (21),[22] USA Jet Airlines (7), Everts Air Cargo (5), Aeronaves TSM (4), Aserca Airlines (4),[23] LASER Airlines (4), and other operators with fewer aircraft.[24][25]
Delta Air Lines has, since acquiring Northwest Airlines, operated a fleet of DC-9 aircraft, most of which are over 30 years old. With severe increases in fuel prices in the summer of 2008, Northwest Airlines finally began retiring its DC-9s, switching to Airbus A319s that are 27% more fuel efficient.[26][27]
Because of the usage of the aging JT8D engines, as of late 2000s (decade) DC-9s are considered gas guzzlers when compared to other more recent airliner designs. Studies aimed at improving DC-9 fuel efficiency, by means of retrofitted wingtip extensions of various types, have not succeeded in demonstrating significant benefits.
With the existing DC-9 fleet shrinking, modifications do not appear to be likely to occur, especially since the wing design makes retrofitting difficult.[11] Thus, DC-9s are likely to be further replaced in service by new Boeing 737, Airbus A320, Embraer E-Jets aircraft, or the new, emerging Bombardier CSeries airliner.[28] However, it is probable that a modest number of DC-9s will continue to productively fly for many years to come. As the Northwest/Delta merger progressed, Delta pulled several stored DC-9s back into service.
One ex-SAS DC-9-21 is operated as a skydiving jump platform at Perris Valley Airport in Perris, California. With the steps on the ventral stairs removed, it is the only airline transport class jet certified to date by the FAA for skydiving operations as of 2008.[29]
Accidents and incidents
As of March 2009, the DC-9 has been involved in 117 incidents, including 101 hull-loss accidents,[31] with 2,135 fatalities.[32]
[edit]Notable accidents
On October 1, 1966, West Coast Airlines Flight 956 crashed with eighteen fatalities and no survivors. This accident marks the first loss of a DC-9.[33]
On March 9, 1967, TWA Flight 553 fell to earth in a field in Concord Township, near Urbana, Ohio, following a mid-air collision with a Beechcraft Baron, an accident which triggered substantial changes in air traffic control procedures.[34] All 25 people on board the DC-9 were killed.
On March 17, 1969, Viasa Flight 742 crashed into the La Trinidad neighborhood of Maracaibo during a failed take-off. All 84 people on board the aircraft as well as 71 people on the ground were killed. At that time Viasa Flight 742 was the worst disaster in aviation history.[35]
On June 27, 1969, Douglas DC-9-31 N906H of Hawaiian Airlines collided on the ground with Vickers Viscount N7410 of Aloha Airlines at Honolulu International Airport. The Viscount was damaged beyond repair.[36]
On September 9, 1969, Allegheny Airlines Flight 853, a DC-9-30, collided in mid-air with a Piper PA-28 Cherokee near Fairland, Indiana. The DC-9 carried 78 passengers and 4 crew members, the Piper one pilot. The occupants of both aircraft were killed in the accident and the aircraft were destroyed.[37][38]
On February 15, 1970, a Dominicana de Aviación DC-9 crashed after taking off from Santo Domingo, in what is known as the Dominicana DC-9 air disaster. The crash, possibly caused by contaminated fuel, killed all 102 passengers and crew, including champion boxer Teo Cruz.[39][40]
On May 2, 1970, an Overseas National Airways DC-9, wet-leased to ALM Dutch Antilles Airlines and operating as ALM Flight 980, ditched in the Caribbean Sea on a flight from New York's John F. Kennedy International Airport to Princess Juliana International Airport on Sint Maarten. After three landing attempts in poor weather at Sint Maarten, the pilots began to divert to their alternate of Saint Croix, U.S. Virgin Islands but ran out of fuel 30 mi (48 km) short of the island. After about 10 minutes, the aircraft sank in 5,000 ft (1524 m) of water and was never recovered. 40 people survived the ditching, 23 perished.[41]
On November 14, 1970, Southern Airways Flight 932, a DC-9, crashed into a hill near Tri-State Airport in Huntington, West Virginia. All 75 on board were killed (including 37 members of the Marshall University Thundering Herd football team, eight members of the coaching staff, 25 boosters, and others).
On January 26, 1972, Jugoslovenski Aero Transport Flight 367, in flight from Stockholm to Belgrade, DC-9-32 registration YU-AHT, was destroyed in flight by a bomb placed on board. The sole survivor was a flight attendant, Vesna Vulovic, who holds the record for the world's longest fall without a parachute when she fell some 33,000 ft (10,000 m) inside the tail section of the airplane and survived.
On December 20, 1972, North Central Airlines Flight 575, DC-9-31 registration N954N, collided during its takeoff roll with Delta Air Lines Flight 954, a Convair CV-880 that was taxiing across the same runway at O'Hare International Airport in Chicago, Illinois, in what is known as the 1972 Chicago-O'Hare runway collision. The DC-9 was destroyed, killing 10 and injuring 15 of the 45 people on board; two people among the 93 aboard the Convair 880 suffered minor injuries.[42]
On July 31, 1973, Delta Air Lines Flight 723, DC-9-31 registration N975NE, crashed into a seawall at Logan International Airport in Boston, Massachusetts, killing all 83 passengers and 6 crew members on board. One of the passengers initially survived the accident but later died in a hospital.
On September 11, 1974, Eastern Air Lines Flight 212, a DC-9-30 crashed just short of the runway at Charlotte, North Carolina, killing 71 out of the 82 occupants.
On 30 October 1975, an Inex-Adria Aviopromet DC-9-32 hit high ground during an approach in fog near Prague-Suchdol, Czechoslovakia. 75 people were killed.[43]
On September 10, 1976, an Inex-Adria Aviopromet DC-9 collided with a British Airways Trident over the Croatian town of Vrbovec, killing all 176 people aboard both aircraft, in what is known as the 1976 Zagreb mid-air collision.
On April 4, 1977, Southern Airways Flight 242, a DC-9-31, lost engine power in a storm then crash landed onto a highway in New Hope, Georgia, US, striking road side buildings. The crash and fire resulted in the death of both flight crew and 61 passengers. Nine people on the ground also died. Both flight attendants and 20 passengers survived.[44][45]
On June 26, 1978, Air Canada Flight 189, a DC-9 overran the runway in Toronto after a blown tire aborted the takeoff. Two of the 107 passengers and crew were killed.[46]
On September 14, 1979, Aero Trasporti Italiani Flight 12, a DC-9-32 crashed in the mountains near Cagliari, Italy while approaching Cagliari-Elmas Airport. All 27 passengers and 4 crew members died in the crash and ensuing fire.[47]
An Itavia DC-9 (registration I-TIGI) which was lost in an accident at Ustica in 1980.
On June 27, 1980, Aerolinee Itavia Flight 870, a DC-9-15 suffered an in-flight explosion and crashed into the sea near the Italian island of Ustica. All 81 people on board were killed. The causes of this accident are still unclear.
Itavia DC-9 (I-TIGI) was destroyed in an accident at Ustica. Shown in the "Museo della Memoria" opened in Bologna in 2007.
On July 27, 1981, Aeromexico Flight 230 ran off the runway in Chihuahua. Bad weather and pilot error were blamed.
On June 2, 1983, Air Canada Flight 797, a DC-9 experienced an electrical fire in the aft lavatory during flight, resulting in an emergency landing at Cincinnati/Northern Kentucky International Airport. During evacuation, the sudden influx of oxygen caused a flash fire throughout the cabin, resulting in the deaths of 23 of the 41 passengers, including Canadian folk singer Stan Rogers. All five crew members survived.
On December 7, 1983, the Madrid Runway Disaster took place where a departing Iberia Boeing 727 struck an Aviaco Douglas DC-9 causing the death of 93 passengers and crew. All 42 passengers and crew on board the DC-9 were killed.
On August 31, 1986, Aeroméxico Flight 498 collided in mid-air with a Piper Cherokee over the city of Cerritos, California, then crashed into the city, killing all 67 aboard the aircraft, 15 people on the ground, and all 3 in the small plane.
On 4 April 1987, Garuda Indonesia Flight 035, a DC-9-32, hit a pylon and crashed on approach to Polonia International Airport in bad weather with 24 fatalities.[48]
On December 3, 1990, Northwest Airlines Flight 1482, a DC-9-14, went on the wrong taxiway in dense fog at Detroit-Metropolitan Wayne County Airport, Michigan (DTW). It entered the active runway instead of taxiway instructed by air traffic controllers. It collided with a departing Northwest Boeing 727. Nine people were killed.[49][50]
On July 2, 1994, USAir Flight 1016 crashed in Charlotte, North Carolina while performing a go-around because of heavy storms and wind shear at the approach of runway 18R. There were 37 fatalities and 15 injured among the passengers and crew. Although the airplane came to rest in a residential area with the tail section striking a house, there were no fatalities or injuries on the ground.
On May 11, 1996 ValuJet Flight 592 crashed in the Florida Everglades due to a fire caused by the activation of chemical oxygen generators illegally stored in the hold. The fire damaged the plane's electrical system and eventually overcame the crew, resulting in the deaths of 110 people.
On October 10, 1997, Austral Flight 2553, DC-9-32 registration LV-WEG, en route from Posadas to Buenos Aires, crashed near Fray Bentos, Uruguay, killing 74 people (69 passengers and 5 crew).[51]
On February 2, 1998, Cebu Pacific Flight 387 crashed on the slopes of Mount Sumagaya in Misamis Oriental, Philippines, killing all 104 people on board. Aviation investigators deemed the incident to be caused by pilot error when the plane made a non-regular stopover to Tacloban.
On November 9, 1999, TAESA Flight 725 crashed a few minutes after leaving the Uruapan Airport en route to Mexico City. 18 people were killed in the accident.[52]
On October 6, 2000, Aeroméxico Flight 250, a DC-9-31 en route from Mexico City to Reynosa, Mexico, could not stop at end of runway and crashed into houses and fell into a small canal. Four people on the ground were killed. None of 83 passengers and 5 crew members were killed. The DC-9 was heavily damaged and classified as a loss. The runway had seen heavy rainfall as a result of Hurricane Keith.[53]
On April 15, 2008, a Hewa Bora Airways DC-9 crashed into a residential neighborhood, in the Goma, Democratic Republic of the Congo,[54] resulting in the deaths of at least 44 people,[55] in what is known as the 2008 Goma DC-9 crash.
On July 6, 2008, USA Jet Flight 199, a DC-9-15F, after taking off from Shreveport, LA airport bound for Saltillo, Mexico crashed and burned. The captain was killed and first officer was seriously injured.[56] The cause of the crash is under investigation.
[edit]Aircraft on display
XA-TBX ex-Aerocaribe- Preserved at Venustiano Carranza at Benito Juarez International Airport as a public hi-tech library
ex-N8903E Northwest Airlines- Preserved at TVF since 15-04-1998 as a donation to the Northland Community & Technical College
ex-Air Canada C16Y70 preserved and on display at the Canada Aviation Museum
ex-Iberia Airways EC-BQZ-CY105 Preserved at MAD on display between terminals 1 and 2, used as theater by AENA
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The McDonnell Douglas DC-10 is a three-engine widebody jet airliner manufactured by McDonnell Douglas. The DC-10 has range for medium- to long-haul flights, capable of carrying a maximum 380 passengers. Its most distinguishing feature is the two turbofan engines mounted on underwing pylons and a third engine at the base of the vertical stabilizer. The model was a successor to McDonnell Douglas's DC-8 for long-range operations, and competed in the same markets as the Lockheed L-1011 Tristar, which has a similar layout to the DC-10.
Production of the DC-10 ended in 1989 with 386 delivered to airlines and 60 to the U.S. Air Force as air-to-air refueling tankers, designated the KC-10 Extender.[2] The largest operator of the DC-10 is U.S. cargo airline FedEx Express. The DC-10 was succeeded by the related McDonnell Douglas MD-11. Boeing, who merged with McDonnell Douglas in the 1990s, conducted an upgrade program for the DC-10s, equipping several with a glass cockpit, leading to the re-designation as MD-10s.
Development
Following an unsuccessful proposal for the U.S. Air Force's CX-HLS (Heavy Logistics System) in 1965, Douglas Aircraft began design studies based on its CX-HLS design. In 1966, American Airlines offered a specification to manufacturers for a widebody aircraft smaller than the Boeing 747 but capable of flying similar long-range routes from airports with shorter runways. The DC-10 became McDonnell Douglas's first commercial airliner after the merger between McDonnell Aircraft Corporation and Douglas Aircraft Company in 1967.[3] An early DC-10 design proposal was for a four-engined double deck wide-body jet airliner with a maximum seating capacity of 550 passengers similar in length of 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 similar in length to a DC-8 Super 60.[4]
British Caledonian DC-10-30 at London Gatwick Airport in 1988
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.[5][6] That year, the world's demand for commercial airliners was 724 aircraft.[7] The DC-10, a series 10 model, made its first flight on August 29, 1970.[8] Following a flight test program with 929 flights covering 1,551 hours, the DC-10 was awarded a type certificate from the FAA on July 29, 1971.[9] It entered commercial service with American Airlines on August 5, 1971 on a round trip flight between Los Angeles and Chicago. United Airlines began DC-10 service on August 16, 1971.[10] The DC-10's similarity to the L-1011 in terms of passenger capacity and launch in the same timeframe resulted in a head to head sales competition which affected profitability of the aircraft.
The first DC-10 version was the "domestic" series 10 with a range of 3,800 miles (3,300 nmi, 6,110 km) with a typical passenger load and a range of 2,710 miles (2,350 nmi, 4,360 km) with maximum payload. The series 15 had a typical load range of 4,350 miles (3,780 nmi, 7,000 km).[11][12] The series 20 was powered by Pratt & Whitney JT9D turbofan engines, whereas the series 10 and 30 engines were General Electric CF6. Before delivery of its aircraft, Northwest's president asked that the "series 20" aircraft be redesignated "series 40" because the aircraft was much improved over the original design. The FAA issued the series 40 certificate on October 27, 1972.[13]
A FedEx Express MD-10-10, a modernized DC-10-10
The series 30 and 40 were the longer range "international" versions. One of the main visible differences between 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 four gear (one front, three main). The center main two-wheel landing gear (which extends from the center of the fuselage) was added to accommodate the extra weight by distributing the weight and providing additional braking. The series 30 had a typical load range of 6,220 mi (10,010 km) and a maximum payload range of 4,604 mi (7,410 km). The series 40 had a typical load range of 5,750 miles (9,265 km) and a maximum payload range of 4,030 miles (3,500 nmi, 6,490 km).[11][14]
Eventually, the DC-10 was able to distinguish itself from its competitors with two engine options, as well as earlier introduction of longer range variants than the L-1011. The 446th and final DC-10 rolled off the production line in December 1988 and was delivered to Nigeria Airways in July 1989.[15] The DC-10 was assembled at McDonnell Douglas's Douglas Products Division in Long Beach, California.[2] As the final few DC-10 deliveries were occurring, McDonnell Douglas had already started production of the DC-10's successor, the MD-11.[16]
[edit]Design
Northwest Airlines DC-10-30 at London Gatwick Airport in 2003
The DC-10 is a low-wing cantilever monoplane, powered by three turbofan engines. Two 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. The vertical stabilizer, with its two-segment rudder, is mounted on top of the tail engine banjo. The horizontal stabilizer and its four-segment elevator, is attached to the sides of the rear fuselage in the conventional manner. The airliner has a 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.[17]
It was designed for medium to long-range flights that can accommodate 250 to 380 passengers, and is operated by a cockpit flight crew of three. The fuselage has underfloor stowage for cargo and baggage.[18]
[edit]Variants
DC-10-30 flight deck
[edit]Original variants
DC-10-10
The DC-10-10 is the initial passenger version, produced from 1970 to 1981. The DC-10-10 was equipped with GE CF6-6 engines, which was the first civil engine version the CF6 family. A total of 122 were built.[19]
DC-10-10CF
The -10CF is a convertible passenger and cargo transport version of the -10. Eight were built for Continental Airlines and one for United Airlines.[19]
DC-10-15
The -15 variant was designed for use at hot, high-altitude airports. The series 15 is basically a -10 fitted with higher-thrust GE CF6-50C2F (derated DC-10-30 engines) powerplants.[20] The -15 was first ordered in 1979 by Mexicana and Aeroméxico. Seven were completed between 1981 and 1983.[21]
[edit]Longer range variants
DC-10-20
A proposed version of the DC-10-10 with extra fuel tanks, 3-ft (0.9 m) extensions on each wingtip and a rear center landing gear. It was to use Pratt & Whitney JT9D-15 turbofan engines, each producing 45,500 lbf (203 kN) of thrust, with a maximum takeoff weight of 530,000 lb (240,400 kg). But engine improvements led to increased thrust and increased takeoff weight.[22] Northwest Orient Airlines, one of the launch customers for this longer range DC-10 requested the name change to DC-10-40.[23]
Interior of a DC-10-30 operated by Biman, the flag carrier of Bangladesh
DC-10-30
A long-range model and the most common model produced. It was built with General Electric CF6-50 turbofan engines and larger fuel tanks to increase range and fuel efficiency, as well as a set of rear center landing gear to support the increased weight. It was very popular with European flag carriers. A total of 163 were built from 1972 to 1988 and delivered to 38 different customers.[24] The model was introduced in service on November 30, 1972, with Swissair and KLM as its first customers.[citation needed]
DC-10-30CF
The convertible cargo/passenger transport version of the -30. The first deliveries were to Overseas National Airways and Trans International Airlines in 1973. A total of 27 were built.[19]
DC-10-30ER
The extended range version of the -30. The -30ER aircraft has a higher maximum takeoff weight of 580,000 lb (263,160 kg), are powered by three GE CF6-50C2B engines each producing 54,000 lbf (240 kN) of thrust and are equipped with an additional fuel tank in the rear cargo hold.[25] It has an additional 700 mi of range to 6,600 mi (5,730 nmi, 10,620 km. The first of this variant was delivered to Finnair in 1981. A total of six were built and five -30s were later converted to -30ERs.
DC-10-30AF
Also known as the DC-10-30F. This was the all freight version of the -30. Production was to start in 1979, but Alitalia did not confirm its order then. Production began in May 1984 after the first aircraft order from FedEx. A total of 10 were built.[26]
Japan Airlines DC-10-40
DC-10-40
The first long-range version fitted with Pratt & Whitney JT9D engines. Originally designated DC-10-20, this model was renamed DC-10-40 after a special request from Northwest Orient Airlines as the aircraft was much improved compared to its original design, with a higher MTOW (on par with the Series 30) and more powerful engines. The airline's president wanted to advertise he had the latest version.[23][27] The company also wanted their aircraft to be equipped with the same engines as their Boeing 747s for commonality.[28] Northwest Orient Airlines and Japan Airlines were the only airlines to order the series 40 with 22 and 20 aircraft, respectively. Engine improvements led to the DC-10-40s delivered to Northwest featuring Pratt & Whitney JT9D-20 engines producing 50,000 lbf (222 kN) of thrust and a MTOW of 555,000 lb (251,815 kg). The -40s for Japan Airlines were equipped with P&W JT9D-59A engines that produced a thrust of 53,000 lbf (235.8 kN) and a MTOW of 565,000 lb (256,350 kg).[22] 42 were built from 1973 to 1983.[29]
DC-10-50
A proposed version with Rolls-Royce RB211-524 engines for British Airways. The order never came and the plans for the DC-10-50 were abandoned.[30]
DC-10 "Twin"
A proposed DC-10 version with two CF-6 engines, likely designed to compete against the Airbus A300.[citation needed]
[edit]Tanker versions
A USAF KC-10 Extender during refueling
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.[31]
The KDC-10 is an aerial refueling tanker for 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 two KDC-10 tankers for lease. Four have been built.[32][33]
The 10 Tanker Air Carrier DC-10-10 during a water drop demonstration
The 10 Tanker Air Carrier is a DC-10-10 converted into a firefighting tanker aircraft, using modified water tanks from Erickson Air-Crane.
[edit]MD-10 upgrade
The MD-10 is retrofit cockpit upgrade to the DC-10 and a re-designation to MD-10. The upgrade included an Advanced Common Flightdeck (ACF) used on the MD-11.[34] The new cockpit eliminated the need for the flight engineer position and allowed common type rating with the MD-11. This allows companies such as FedEx Express, which operate both the MD-10 and MD-11, to have 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 the conversions.[35]
[edit]Operators
DC-10-30 of Biman Bangladesh, one of the two remaining passenger airlines that operate the jetliner, with landing gear extended on final approach to London Heathrow, 2003
See also: List of McDonnell Douglas DC-10 operators
On January 8, 2007, Northwest Airlines retired its last remaining DC-10 from scheduled passenger service, replacing it with an Airbus A330 for a route between Minneapolis-St. Paul and Honolulu,[36] 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."[37] "The DC-10 is going to be remembered as a better cargo plane than passenger plane," said Richard Aboulafia, an analyst with the Teal Group.[37] In November 2006 ATA Airlines announced that they had purchased seven of Northwest's remaining DC-10s to replace their Lockheed L-1011s. Omni Air International purchased six of Northwest's DC-10 aircraft.[38]
The aging models are now largely used as dedicated freight aircraft. American Airlines and United Airlines sold their large DC-10-10 fleets to cargo carrier FedEx. Many have been modernized to MD-10s by adding a glass cockpit, which eliminates the need for a flight engineer. Other DC-10 aircraft continue in charter and cargo services with their three-person flight deck configuration. Omni Air International and World Airways continue to operate the DC-10 on charter passenger services as well as for the Air Mobility Command. Biman Bangladesh Airlines operates five DC-10-30s as one of their primary passenger aircraft as of 2009.[39]
The Orbis DC-10 Flying Eye Hospital, February 2009
Non-airline operators include the Royal Netherlands Air Force with three DC-10-30CF-based KDC-10 tanker aircraft, the USAF with its 59 KC-10s, and the 10 Tanker Air Carrier with its modified DC-10-10 used for fighting wildfires.[40] Orbis International has used a single DC-10-10 converted into a flying eye hospital. Surgery is performed on the ground and the operating room is located between the wings for maximum stability.[41] Orbis chose to replace its aging DC-10 with a MD-10,[42] that was converted from a DC-10 jointly donated by FedEx and United Airlines.[43] The MD-10 eye hospital is expected to be flying in 2010.[43][44] Additionally, one former American Airlines DC-10-10 is operated by the Missile Defense Agency as the Widebody Airborne Sensor Platform (WASP).[45]
In January 2011, there were 97 DC-10s in service with commercial operators FedEx Express (74), Biman Bangladesh Airlines (4), Kelowna Flightcraft Air Charter (3), and others with fewer aircraft.[46][47] [48]
[edit]Incidents and accidents
As of January 2012, the DC-10 was involved in 56 aviation occurrences,[49] including 32 hull-loss accidents,[50] with 1,262 occupant fatalities.[51] It has been involved in nine hijackings and criminal events resulting in 171 occupant fatalities.[51] Despite its troubled beginnings in the 1970s, which gave it an unfavorable reputation,[52] the DC-10 has proved a reliable aircraft.[53] The DC-10's initially poor safety record continuously improved as design flaws were rectified and fleet hours increased.[53] The DC-10's lifetime safety record is comparable to similar second-generation passenger jets as of 2008.[54]
[edit]Cargo door problem
The DC-10 was designed with cargo doors that opened outward instead of conventional inward-opening "plug-type" doors. Using outward-opening doors allowed the DC-10's cargo area to be completely filled since the door was not occupying usable space. To secure the door against the outward force from the 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 great potential for explosive decompression.[55]
[edit]American Airlines Flight 96
A problem with the outward-opening cargo door first became publicly known on June 12, 1972, when American Airlines Flight 96 lost its aft cargo door shortly after takeoff from Detroit Metro Airport. Before Flight 96 took off, an airport employee had forced the door shut, which, due to the cargo door's design, gave an outward appearance of being securely locked despite the internal locking mechanism's not being fully engaged. Subsequently, when the plane reached approximately 11,750 feet (3,580 m) in altitude, the cargo door blew out, causing an explosive decompression which partially collapsed the cabin floor at the rear of the plane. This collapsed section of the floor cut or impeded many of the control cables to the empennage control systems necessary to fly the plane.[56][57] The crew was able to accomplish an emergency landing by using the ailerons, right elevator, some limited rudder trim and asymmetrical thrust of the wing engines.[58]
During the investigation of the near-crash of Flight 96, U.S. National Transportation Safety Board (NTSB) investigators found that the DC-10's cargo door design was dangerously flawed. The door relied on a set of heavy steel hooks to secure it against the door frame. When the hooks were fully engaged, an outside lever on the cargo door could be depressed, which drives a set of locking pins through the hooks, holding them in place. The NTSB investigation found that it was possible to close the outside lever without the hooks being fully engaged, and there would be no outward signs that the locking mechanism was not engaged. Even though the hooks and locking pins were not in the closed position, the cargo door indicator in the cockpit would still register the door as being secured. This combination of factors caused Flight 96 to take off without its aft cargo door being fully locked. And when the door blew out at altitude, the sudden decompression of the airplane caused a large pressure difference to build up between the cabin above and the cargo bay below. This depressurization loading is what caused the cabin floor to collapse.[59] And because the DC-10 was designed with its hydraulics and control wires routed through the floor beams, the collapse of the cabin floor caused a loss of vital flight controls.[56]
FedEx became the first U.S. carrier to equip its aircraft with an anti-missile defense system in 2006. The gray oval Northrop Grumman Guardian pod can be seen on the belly of this FedEx MD-10 between and just aft of the main landing gear.
Following the Windsor incident investigation, the NTSB made several recommendations, including repairing the faulty cargo door design to make it impossible for baggage handlers to close the cargo door lever without the locking pins being fully engaged. It was also recommended that vents be installed in the cabin floor so that, in case of an explosive decompression, the pressure difference between the cabin and cargo bay could quickly be equalized without collapsing the cabin floor and damaging critical control systems.[59] Although many carriers voluntarily modified the cargo doors, no airworthiness directive was issued to require reworking of the locking system, due to a gentlemen's agreement between the head of the FAA and McDonnell Douglas. McDonnell Douglas did make modifications to the cargo door, but the basic design remained unchanged and problems persisted.[59]
[edit]Turkish Airlines Flight 981
On March 3, 1974, an almost identical cargo door blow-out caused Turkish Airlines Flight 981 to crash into a forest near the town of Ermenonville, France shortly after leaving Paris.[59] All 346 people were killed[60] in one of the deadliest air crashes of all time.[61] Circumstances of this crash were very similar to the previous accident. The cargo door had not been fully locked, though it appeared so to both cockpit crew and ground personnel. The Turkish aircraft had a different seating configuration that exacerbated the effects of decompression, which caused the aircraft's floor to collapse into the cargo bay. Control cables running through the floor of the plane were severed when the floor collapsed and this rendered the aircraft uncontrollable.[59] Crash 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.[60] Following this crash, a special subcommittee of the House of Representatives investigated the cargo door issue and the FAA's certification of the original design.[62] An airworthiness directive was issued, and all DC-10s underwent mandatory door modifications.[62] The DC-10 experienced no more major incidents related to its cargo door after FAA-approved changes were made.[59]
[edit]American Airlines Flight 191
The DC-10 experienced another major accident with the crash of American Airlines Flight 191 on May 25, 1979. Flight 191 lost its number one (left wing) engine after taking off from O'Hare International Airport in Chicago, USA.[63] As the engine separated upwards, it ripped through the leading edge of the wing, rupturing hydraulic lines. Without hydraulic pressure, the left wing leading edge slats retracted due to the force of the air moving over the wings. That, in turn, increased the stall speed of the left wing above the engine failure climb out speed being used by the pilots. When the left wing stalled, the aircraft rapidly rolled to the left and crashed before the flight crew could recover. All 271 people on board, plus two on the ground, were killed.[64]
The United States National Transportation Safety Board (NTSB) officials discovered that a maintenance procedure was the culprit. American Airlines mechanics removed the engine and its pylon together, rather than removing the engine from the pylon then the pylon from the wing, as recommended by McDonnell Douglas. This was done using a forklift and the pylon was inadvertently cracked in the process. The short-cut procedure, believed to save many man hours on maintenance, was used by three major airlines, although McDonnell Douglas advised against it.[65] In November 1979, the Federal Aviation Administration (FAA) fined American Airlines $500,000 for using this faulty maintenance procedure. Continental Airlines was fined $100,000 on a similar charge.[65][66]
The Chicago accident also highlighted a major deficiency in the DC-10 design; its lack of a locking mechanism to maintain the position of the leading-edge slats in the event of a hydraulic or pneumatic failure.[65] Other wide-body aircraft of the day carried such a feature. When the engine pulled up and over the wing, it tore out electrical wiring in the wing, thus rendering vital warning instruments in the cockpit inoperable. Following the Chicago crash, the FAA withdrew the DC-10's type certificate on June 6, 1979, which grounded U.S. DC-10s. It also barred all DC-10s from U.S. airspace. These measures were rescinded on July 13 after modifications were made to the slat actuation and position systems, along with stall warning and power supply changes.[67][65]
[edit]United Airlines Flight 232
Another major DC-10 crash was United Airlines Flight 232 disaster at Sioux City, Iowa, USA, on July 19, 1989. The number two (tail) engine suffered an uncontained fan disk failure in flight, which damaged all three hydraulic systems and rendered the hydraulic flight controls inoperable. The flight crew, led by Captain Al Haynes and assisted by a senior pilot flying as a passenger (Dennis E. "Denny" Fitch), performed an emergency landing by constantly adjusting the thrust of the remaining two engines. The crew managed to fly the aircraft onto the runway in a partially controlled manner, and 185 of the 296 people on board survived in spite of the destruction of the plane during that landing.[68]
The DC-10 included no cable backup for the hydraulic powered flight controls because it was considered nearly impossible for three hydraulic systems to fail during one flight, and furthermore the control surfaces are too large to be moved without hydraulic assistance. However, all three hydraulic systems were in close proximity, directly beneath the tail engine. The #2 engine explosion hurled shrapnel that ruptured all three lines, resulting in total loss of control to the elevators, ailerons, spoilers, horizontal stabilizer, rudder, flaps and slats.[68]
Following the UAL 232 accident, hydraulic fuses were installed in the #3 hydraulic system in the area below the #2 engine on all DC-10 aircraft to ensure that sufficient control capability remained if all three hydraulic system lines should be damaged in the tail area. It is still possible to lose all three hydraulic systems elsewhere. That nearly occurred to a cargo airliner in 2002 during takeoff, when a main gear tire exploded in the wheel well. The damage in the left wing area caused total loss of pressure in the #1 and the #2 hydraulic systems. The #3 system was dented but not penetrated.[69]
[edit]Other notable accidents and incidents
Other notable incidents and accidents involving the DC-10 are listed below.
November 3, 1973 - National Airlines Flight 27, a DC-10-10 experienced an uncontained failure of the right (#3) engine. The cabin was penetrated by shrapnel from the engine and lost pressure. One passenger was killed. The crew initiated an emergency descent, and landed the aircraft safely.
October 31, 1979 - Western Airlines Flight 2605, a DC-10-10 crashed while landing at Mexico City International Airport. 72 out of 88 people died.
November 28, 1979 - Air New Zealand Flight 901, DC-10-30 ZK-NZP crashed into Mount Erebus on Ross Island, Antarctica during a sightseeing flight over the continent, killing all 257 on board. The accident was caused by the flight coordinates being altered without the flight crew's knowledge, combined with unique Antarctic weather conditions.
January 23, 1982 - World Airways Flight 30, a DC-10-30CF, registration N113WA, overran the runway at Boston Logan International Airport. All 12 crew survived, but two of the 200 passengers were never found and assumed dead.[70]
September 13, 1982 – Spantax Flight BX995, DC-10-30CF EC-DEG was destroyed by fire after an aborted take-off at Málaga, Spain. 50 passengers were killed and 110 passengers were injured due to the flames.
December 23, 1983 – Korean Air Cargo Flight 084, DC-10-30CF HL7339 was destroyed after colliding head-on with a Piper PA-31 Navajo while taxiing at Anchorage, Alaska. All on board both aircraft survived.
July 27, 1989 – Korean Air Flight 803, DC-10-30, registration HL7328 crashed short of the runway in bad weather while trying to land at Tripoli, Libya. A total of 75 of the 199 on board plus another four people on the ground were killed in the accident.[71]
September 19, 1989 – UTA Flight 772, DC-10-30 N54629, crashed in Ténéré Desert following an in-flight bomb explosion, claiming the lives of all on board.
December 21, 1992 – Martinair Flight 495, DC-10-30CF PH-MBN crashed while landing in bad weather at Faro, Portugal.
April 7, 1994 - FedEx Flight 705, DC-10-30 N306FE experienced an attempted hijacking. FedEx employee Auburn Calloway tried to hijack the plane, but the crew fought him off and returned to Memphis.
June 13, 1996 – Garuda Indonesia Flight 865, DC-10-30 PK-GIE had just taken off from Fukuoka Airport, Japan when a high-pressure blade from engine #3 separated. The aircraft was just a few feet above the runway and the pilot decided to abort the take-off. Consequently, the DC-10 skidded off the runway and came to a halt 1,600 ft (490 m) past it, having lost one of its engines and its landing gear.
January 31, 2001 - Japan Airlines Flight 958, bound for Narita International Airport from Gimhae International Airport, nearly collided with another Japan Airlines aircraft. The other aircraft, a Boeing 747, dived and avoided the Narita-bound DC-10.
December 25, 2000 - Hawaiian Airlines Flight 481, from Honolulu to Tahiti, Faaa International Airport, overshot the runway in a driving rain storm and stopped with its front wheel in a lagoon.[72]
The Air France Concorde crash of 2000 was attributed to a fragment of titanium that fell from the thrust reverser of a Continental Airlines DC-10 that had taken off four minutes earlier. This fragment was traced to a third party parts replacement that had not been approved by the FAA.
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The McDonnell Douglas DC-9-10/20/30
Country of origin
United States of America
Photos
Powerplants
10 - Two 54.5kN (12,250lb) Pratt & Whitney JT8D-5 turbofans.
30 - Two 64.5kN (14,500lb) JT8D-9s, or two 66.7kN (15,000lb) JT8D-11s, or two 71.2kN (16,000lb) JT8D-17s.
Performance
10 - Max cruising speed 903km/h (488kt), economical cruising speed 885km/h (478kt). Range with max payload 1055km (570nm).
30 - Max cruising speed 907km/h (490kt), long range cruise 798km/h (430kt). Range at high speed cruise with 64 passengers and reserves 2150km (1160nm), range at long range cruise with 80 passengers and reserves 3095km (1670nm).
Weights
10 - Operating empty 22,635kg (49,900lb), max takeoff 41,140kg (90,700lb).
30 - Empty 25,940kg (57,190lb), max takeoff 54,885kg (121,000lb).
Dimensions
10 - Wing span 27.25m (89ft 5in), length 31.82m (104ft 5in), height 8.38m (27ft 6in). Wing area 86.8m2 (934sq ft).
30 - Same except for length 36.37m (119ft 4in), wing span 28.47m (93ft 5in). Wing area 93.0m2 (1000.7sq ft).
Capacity
Flightcrew of two.
10 - Seating for 80 in a single class at five abreast and 86cm (34in) pitch. Max seating for 90.
30 - Max seating for 115 in a single class, five abreast and 81cm (32in) pitch, standard single class seating for 105.
30CF - can carry over eight cargo pallets.
Production
976 DC-9s of all models built including 137 -10s, 10 -20s and 662 -30s (including military C-9s). 97 DC-9-10s, 4 DC-9-20s and 381 DC-9-30s in airline service at late 2002. 9 DC-9-10s and 3 DC-9-30s used as corporate jets at late 2002.
Type
Short range airliners
History
No other airliner in history has undergone more development than the prolific DC-9/MD-80/MD-90/717 series, which started life with the 70 seat DC-9-10 of the early sixties.
Douglas developed the DC-9 as a short range airliner complementing the much larger DC-8. Development was launched on April 8 1963, with a launch order from Delta following soon after. The DC-9 was an all new design, featuring rear fuselage mounted engines, a T-tail, moderately swept wings and seats for up to 90 passengers in a five abreast fuselage.
Construction of the prototype began in July 1963 and the first flight occurred on February 25 1965. Certification and service entry was on November 23 and December 8 1965, respectively.
From the outset the DC-9 had been designed with stretched larger capacity developments in mind. The first stretch resulted in the biggest selling DC-9, the 4.54m (14ft 11in) longer, 105 seat DC-9-30, which entered service with Eastern on February 1 1967. Subsequent stretched versions are described separately.
Small numbers of developed versions of the DC-9-10 were also built. The DC-9-20 featured the DC-9-10's fuselage with the 30's more powerful engines and longer span wings, giving better hot and high performance. The DC-9-15 was basically a -10 but with more fuel and higher weights. Factory built convertibles and pure freighters were also offered, while a number of DC-9-30s have been converted to freighters, and/or are having Stage 3 hushkits fitted, further extending their useful service lives.
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