McDonnell Douglas DC-9

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 first 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 on May 23, 2006, production of the DC-9 aircraft family ceased after 41 years.

Design and development

Douglas launched the DC-9 development project in April 1963, intending the DC-9 as a short-range companion to their larger four engined DC-8.^[1] Unlike the competing but slightly larger Boeing 727, which used as many 707 components as possible, the DC-9 was an all-new design. The DC-9 features two rear fuselage-mounted Pratt & Whitney JT8D turbofan engines, small, highly efficient wings, and a T-tail.^[1] In most configurations, DC-9 aircraft have distinctive 5-abreast seating in coach class. The airplane seats 80 to 135 passengers depending on version and seating arrangement.

The DC-9 prototype first flew in February 1965. The second DC-9 flew a few weeks later and entered service with Delta Air Lines in late 1965.^[1] The initial -10 variant would be followed by subsequent growth variants. The final DC-9 variant was the -50, which first flew in 1974. The DC-9 would be a commercial success with 976 built when the production ended in 1982.^[1]

The DC-9 is one of the longest-lasting aircraft in operation. The DC-9's reputation for reliability and efficiency drove strong sales of its successors well into the 2000s. 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 3,000 produced, and the first place Boeing 737 with over 5,000 produced.

The DC-9 was be followed by the introduction of the MD-80 series in 1980. The MD-80 series was originally called DC-9-80 series and was a lengthened DC-9-50 with a higher maximum take-off weight (MTOW) and higher fuel capacity. The MD-80 series features Pratt & Whitney JT8D engines with a higher thrust rating than those found on the DC-9.

The MD-80 series was later developed into the MD-90 in the early 1990s. It features a glass cockpit, first featured on the MD-88 and new high-bypass International Aero V2500 engines. The last variant of the 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.

In 2008, DC-9s and their variants (except the 717) are considered gas guzzlers. Studies aimed at improving DC-9 fuel efficiency, by means of retrofitted wingtip extensions of various types, have not succeeded in demonstrating significant benefits, and with the existing fleets shrinking, are not likely to occur, especially since the wing design makes retrofitting difficult.^[2] Thus, DC-9s are likely to replaced in service by new Boeing 737 or Airbus A320 series aircraft.

Variants

DC-9-10: The earliest and smallest DC-9 was 104.4 feet (31.8 m) long and had a maximum weight of 41 tonnes. Power was a pair of 14,000 lb_f (62.3 kN) Pratt & Whitney JT8D-5s. A total of 137 were built. In August 2006 a total of 46 DC-9-10 aircraft remain in airline service. Major operators include USA Jet Airways (9). Some 12 other airlines operate smaller numbers of the type.^[3]

DC-9-15 and DC-9-20: These were variations on the -10 theme. The -15 added more fuel capacity and higher weights. The -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 delivered to Scandinavian Airlines,^[4] and only a small number of the -15 were made. As of April 2008, one DC-9-21 operates as a skydiving jump platform at Perris Valley Airport in Perris, CA (USA). With the steps on the rear airstair removed, it is the only airline transport class jet certified by the FAA for skydiving operations.^[5] 1Time in South Africa still operates a -15.

DC-9-30: The -30 was the definitive model with 662 produced, accounting for about 60% of production. The -30 entered service in February 1967 with a 14 ft 9 in (4.50 m) fuselage stretch, wingspan increased by just over 3 feet (0.9 m) and a high-lift wing system of leading edge slats gives the Series 30 excellent short-field performance. Gross take-off weight was increased to 110,000 lb (50,000 kg), and P&W JT8D-9A engines rated at 14,500 lbf (65 kN) of thrust to JT8D-11 rated at 15,500 lbf (69 kN) of thrust. In December 2007, a total of 261 DC-9-30 aircraft are in airline service. Major operators include: ABX Air (43), Aero California (13), Aserca Airlines (20) and Northwest Airlines (57). Some 26 other airlines also still operate the type.^{[citation needed]}

DC-9-40: This further stretched 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 a variety of Pratt & Whitney engines of between 64.5 and 71 kN. Seventy-one were produced. In December 2007, a total of 41 DC-9-40 aircraft are in airline service, with ABX Air (29) and Northwest Airlines (12).^{[citation needed]}

DC-9-50: The -50 was the largest DC-9 to fly. It had an 8 ft 2 in (2.5) m fuselage stretch and seats up to 139 passengers. It started revenue service in August 1975 and, aside from the size increase, included a number of detail improvements, a new cabin interior, and quieter JT8D-15 or -17 engines in the 70 kN class. McDonnell Douglas delivered 96. In December 2007 a total of 40 DC-9-50 aircraft are in airline service, with Antrak Air (1), Hewa Bora Airways (1), Aeropostal Alas de Venezuela (2), Northwest Airlines (34) and Tikal Airlines (2).^{[citation needed]} Some visual cues to distinguish this version with other DC-9 variants include side strakes (fins) below the side cockpit windows that are only found in the -50 and the engines are mounted differently so that the reverse thrusters appear higher than the center position found in the other models.

Military and government

Main article: McDonnell Douglas C-9

C-9: Several -30 (with side cargo door) types were utilized by the US Military in C-9A Nightingale medevac configuration for the U.S Air Force and the C-9B Skytrain II version used by the U.S Navy and Marines for fleet logistics support moving both personnel and cargo. The VC-9C is a VIP transport version for the US Air Force.

Versions of the DC-9 are also used by the Kuwait Air Force and Italian Air Force.

Operators

Northwest Airlines operates 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.^[6][7]

Incidents and accidents

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.^[8]

• On February 15, 1970, a Dominicana de Aviacion DC-9 crashed after taking off from Santo Domingo. The crash, caused by contaminated fuel, killed all 101 passengers and crew.^{[citation needed]}

• 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 miles short of the island. After about 10 minutes, the aircraft sank in 5,000 feet of water and was never recovered. 40 people survived the ditching, 23 perished.^[9]

• On November 14, 1970, a Southern Airways Flight 932 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 JU364 DC-9-32 (registration: YU-AHT) was destroyed in flight by a bomb placed on the aircraft. The sole survivor was a flight attendant, Vesna Vulović, who holds the record for the world's longest fall without a parachute when she fell from 33,000 ft (10,160 m) inside the tail section of the airplane and survived.

• On September 11, 1974, Eastern Air Lines Flight 212 DC-9-30 crashed just short of the runway at Charlotte, North Carolina, killing 71 of the occupants.

• 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.

• On April 4, 1977, a Southern Airways Flight 242 DC-9-31 crash landed onto then a highway in New Hope, Georgia, USA. The flight crew and 60 passengers were killed during the forced landing due to impact forces and fire, but 19 of the passengers survived, as well as both flight attendants. Eight people on the ground were also killed.^[10]

• On June 26, 1978, Air Canada Flight 189 DC-9 overran the runway in Toronto after a blown tire aborted the takeoff. 2 of 107 passengers and crew were killed.

• On June 27, 1980, a DC-9-15 carrying Aerolinee Itavia Flight 870 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.

• On December 1, 1981, Inex-Adria Aviopromet Flight 1308 crashed in the mountains while approaching Campo dell'Oro Airport in Ajaccio, Corsica killing 173 passengers and 7 crew members.

• On June 2, 1983, Air Canada Flight 797 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 August 31, 1986, Aeromexico 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 3 December 1990, Northwest Airlines Flight 1482 went on the wrong taxiway in dense fog at Detroit-Metropolitan Wayne County Airport, MI (DTW). It entered the active runway instead of taxiway instructed by ATC. It collided with a Northwest B727 on take off. Nine people were killed.^[11]

• 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.

• In October 1997 Austral Flight 2553, DC-9-32, registration LV-WEG, en route from Posadas to Buenos Aires, crashed near Fray Bentos, Uruguay.

• 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. Flight 387 was supposed to be a direct flight but due to the stopover, the pilots were not familiar with the route.

• On April 15, 2008, a Hewa Bora Airways DC-9 crashed into a residential neighborhood, in the Goma, Democratic Republic of the Congo,^[12] resulting in death of at least 44 people.^[13]

Specifications

	DC-9-10	DC-9-20	DC-9-30	DC-9-40	DC-9-50
Passengers (1 class)	90		115	125	135
Max takeoff weight	90,700 lb (41,100 kg)	98,000 lb (44,500 kg)	110,000 lb (49,900 kg)	114,000 lb (51,700 kg)	121,000 lb (54,900 kg)
Max range	1,265 nmi (2,340 km)	1,850 nmi (3,430 km)	1,635 nmi (3,030 km)	1,685 nmi (3,120 km)	1,635 nmi (3,030 km)
Cruising speed	561 mph (903 km/h)	557 mph (896 km/h)	570 mph (917 km/h)		558 mph (898 km/h)
Length	104 ft 5 in (31.82 m)		119 ft 4 in (36.37 m)	125 ft 7 in (38.28 m)	133 ft 7 in (40.72 m)
Wingspan	89 ft 5 in (27.25 m)	93 ft 5 in (28.47 m)
Tail height	27 ft 5 in (8.38 m)
Powerplants (2x)	Pratt & Whitney JT8D-5	Pratt & Whitney JT8D-11	Pratt & Whitney JT8D-15		Pratt & Whitney JT8D-17
Engine thrust	14,000 lbf (62,275 N)	15,000 lbf (66,723 N)	15,500 lbf (68,947 N)		16,000 lbf (71,172 N)

• Cabin cross section:
  • External width: 10 ft 11.6 in (3.34 m)
  • Internal width: 10 ft 3.7 in (3.14 m)
  • External height: 11 ft 8 in (3.6 m)
  • Internal height: 6 ft 9 in (2.06 m)

Official McDonnell Douglas DC-9 data.^[14]

See also

• Airstair
• N900SA
  

Related development

• C-9 Skytrain/Nightingale
• McDonnell Douglas MD-80 / MD-90
• Boeing 717
  

Comparable aircraft

• BAC-111
• Sud Aviation Caravelle
• Tupolev Tu-134
• Boeing 727
• ACAC ARJ21
• Fokker F28
  

Related lists

• List of civil aircraft
  

References

• Becher, Thomas. Douglas Twinjets, DC-9, MD-80, MD-90 and Boeing 717. The Crowood Press, 2002. ISBN 1-86126-446-1.

External links

• DC-9 page on Boeing.com
• DC-9 history page on Boeing.com
• DC-9-10/20/30 on Airliners.net and DC-9-40/50 on Airliners.net
• DC-9 History on AviationHistoryOnline.com
• Airliners Historical Overviews/Aircraft Specifications/Crash Statistics

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