Douglas DC-3

"DC-3" redirects here. For other uses, see DC-3 (disambiguation).
DC-3
A DC-3 operated in period Scandinavian Airlines colors by Flygande Veteraner flying over Lidingö, Sweden (1989)
Role Airliner and transport aircraft
National origin United States
Manufacturer Douglas Aircraft Company
First flight December 17, 1935
Introduction 1936
Status In active service
Produced 1936–1942, 1950
Number built 607[1]
Unit cost
US$79,500 (equivalent to $1,374,462 in 2015)[2][3]
Developed from Douglas DC-2
Variants Douglas C-47 Skytrain
Lisunov Li-2
Showa/Nakajima L2D
Basler BT-67
Conroy Turbo Three
Conroy Tri-Turbo-Three

The Douglas DC-3 is a fixed-wing propeller-driven airliner. Its cruise speed (207 mph or 333 km/h) and range (1,500 mi or 2,400 km) revolutionized air transport in the 1930s and 1940s. Its lasting effect on the airline industry and World War II makes it one of the most significant transport aircraft ever made.

The DC-3 was a twin-engine metal monoplane, developed as a larger, improved 14-bed sleeper version of the Douglas DC-2. It had many exceptional qualities compared to previous aircraft. It was fast, had a good range and could operate from short runways. Its construction was all-metal. It was reliable, easy to maintain and carried passengers in greater comfort. Before the war it pioneered many air travel routes. It was able to cross the continental United States, making transcontinental flights and worldwide flights possible, and is considered the first airliner that could make money by carrying passengers alone.[4]

Civil DC-3 production ended in 1942 with 607 aircraft being produced. However, together with its military derivative, the C-47 Skytrain (designated the Dakota in RAF Service), and with Russian- and Japanese-built versions, over 16,000 were built. Following the Second World War, the airliner market was flooded with surplus C-47s and other transport aircraft, and attempts to produce an upgraded super DC-3 were a failure.

While the DC-3 was soon made redundant on main routes by more advanced types such as the Douglas DC-6 and Lockheed Constellation, the design continued to prove exceptionally adaptable and useful. Large numbers continue to see service in a wide variety of niche roles well into the 21st century. Approximately 400 DC-3s and converted C-47s are still flying to this day as a testament to the durability of the design, many examples being over 70 years old.[5]

Design and development

"DC" stands for "Douglas Commercial". The DC-3 was the culmination of a development effort that began after an inquiry from Transcontinental and Western Airlines (TWA) to Donald Douglas. TWA's rival in transcontinental air service, United Airlines, was starting service with the Boeing 247 and Boeing refused to sell any 247s to other airlines until United's order for 60 aircraft had been filled.[6] TWA asked Douglas to design and build an aircraft that would allow TWA to compete with United. Douglas' design, the 1933 DC-1, was promising, and led to the DC-2 in 1934. The DC-2 was a success, but there was room for improvement.

Wright R-1820 Cyclone 9 engine of Douglas DC-3 "Flagship Knoxville" of American Airlines[7]

The DC-3 resulted from a marathon telephone call from American Airlines CEO C. R. Smith to Donald Douglas, when Smith persuaded a reluctant Douglas to design a sleeper aircraft based on the DC-2 to replace American's Curtiss Condor II biplanes. (The DC-2's cabin was 66 inches (1.7 m) wide, too narrow for side-by-side berths.) Douglas agreed to go ahead with development only after Smith informed him of American's intention to purchase twenty aircraft. The new aircraft was engineered by a team led by chief engineer Arthur E. Raymond over the next two years, and the prototype DST (Douglas Sleeper Transport) first flew on December 17, 1935 (the 32nd anniversary of the Wright Brothers' flight at Kitty Hawk). Its cabin was 92 in (2.3 m) wide, and a version with 21 seats instead of the 14–16 sleeping berths[8] of the DST was given the designation DC-3. There was no prototype DC-3; the first DC-3 built followed seven DSTs off the production line and was delivered to American Airlines.[9]

A former military C-47B of Air Atlantique taking off at RAF Hullavington (2005)

The DC-3 and DST popularized air travel in the United States. Eastbound transcontinental flights could cross the U.S. in about 15 hours with three refueling stops; westbound trips against the wind took 17 12 hours. A few years earlier such a trip entailed short hops in slower and shorter-range aircraft during the day, coupled with train travel overnight.[10]

A variety of radial engines were available for the DC-3. Early-production civilian aircraft used Wright R-1820 Cyclone 9s, but later aircraft (and most military versions) used the Pratt & Whitney R-1830 Twin Wasp, which gave better high-altitude and single-engine performance. Five DC-3S Super DC-3s with Pratt & Whitney R-2000 Twin Wasps were built in the late 1940s, three of which entered airline service.

Production

Total production of all variants was 16,079.[11] More than 400 remained in commercial service in 1998. Production was as follows:

Production of civil DC-3s ended in 1942. Military versions were produced until the end of the war in 1945. A larger, more powerful Super DC-3 was launched in 1949 to positive reviews.The civilian market, however, was flooded with second-hand C-47s, many of which were converted to passenger and cargo versions. Only five Super DC-3s were built, and three of them were delivered for commercial use. The prototype Super DC-3 served the U.S. Navy with the designation YC-129 alongside 100 R4Ds that had been upgraded to the Super DC-3 specification.

Turboprop conversions

A BSAS C-47–65ARTP powered by two Pratt & Whitney Canada PT6-65AR engines, formerly operated by the National Test Pilot School

From the early 1950s, some DC-3s were modified to use Rolls-Royce Dart engines, as in the Conroy Turbo Three. Other conversions featured Armstrong Siddeley Mamba and Pratt & Whitney PT6A turbines.

The Greenwich Aircraft Corp DC-3-TP is a conversion with an extended fuselage and with Pratt & Whitney Canada PT6A-65AR or PT6A-67R engines fitted.[12][13][14]

The Basler BT-67 is a conversion of the DC-3/C-47. Basler refurbishes C-47s and DC-3s at Oshkosh, Wisconsin, fitting them with Pratt & Whitney Canada PT6A-67R turboprop engines, lengthening the fuselage by 40 in (100 cm) with a fuselage plug ahead of the wing and strengthening the airframe in selected areas.[15]

BSAS International in South Africa is another company able to perform a Pratt & Whitney PT6 turboprop conversion of DC-3s. Over 50 DC-3/C-47s / 65ARTP / 67RTP / 67FTPs have been modified.[16]

Conroy Aircraft also made a three-engined conversion with Pratt & Whitney Canada PT6 called the Conroy Tri-Turbo-Three.

Operational history

Douglas C-47B of Aigle Azur (France) in 1953, fitted with a ventral Turbomeca Palas booster jet for hot and high operations
Air India Douglas DC-3 at London Heathrow Airport in July, 1958
DC-3 of Iranian National Airways at Manchester Airport in 1954
DC-3 on amphibious EDO floats. Sun-n-Fun 2003, Lakeland, Florida, United States
Cathay Pacific inaugurated operations in 1946 with a DC-3 named Betsy, now an exhibit in the Hong Kong Science Museum.
C-47 Skytrains unloading at Tempelhof Airport during the Berlin Airlift

American Airlines inaugurated passenger service on June 26, 1936, with simultaneous flights from Newark, New Jersey and Chicago, Illinois.[17] Early U.S. airlines like American, United, TWA, Delta and Eastern ordered over 400 DC-3s. These fleets paved the way for the modern American air travel industry, which eventually replaced trains as the favored means of long-distance travel across the United States. A nonprofit group, Flagship Detroit Foundation, continues to operate the only original American Airlines Flagship DC-3 with air show and airport visits throughout the U.S.[18]

In 1936, KLM Royal Dutch Airlines received its first DC-3 (in 1943 it was downed by Luftwaffe fighters while on a scheduled passenger flight), which replaced the DC-2 in service from Amsterdam via Batavia (now Jakarta) to Sydney, by far the world's longest scheduled route at the time. In total KLM bought 23 DC-3s before the war broke out in Europe. In 1941, a China National Aviation Corporation (CNAC) DC-3 pressed into wartime transportation service was bombed on the ground at Suifu airfield in China, completely destroying the right wing. The only spare wing available was that of a smaller Douglas DC-2 being overhauled in CNAC's workshops. The DC-2's right wing was taken off, flown to Suifu under the belly of another CNAC DC-3, and grafted to the damaged aircraft. After a single test flight, in which it was discovered that it pulled to the right due to the difference in wing sizes, the so-called DC-2½ was returned to service.[19]

Cubana de Aviación became the first Latin American airline to offer a scheduled service to Miami when it started its first scheduled international service from Havana to Miami in 1945 with a DC-3. Cubana used DC-3s on some domestic routes well into the 1960s.[20][21]

Piedmont Airlines operated DC-3s and C-47s from 1948 to 1963. A DC-3 painted in the representative markings of Piedmont, operated by the Carolinas Aviation Museum, was retired from flight in March 2011. Both Delta Air Lines and Continental Airlines once operated commemorative DC-3s wearing period markings.

During World War II, many civilian DC-3s were drafted for the war effort and just over 10,000 U.S. military versions of the DC-3 were built, under the designations C-47, C-53, R4D, and Dakota. Peak production was reached in 1944, with 4,853 being delivered. The armed forces of many countries used the DC-3 and its military variants for the transport of troops, cargo, and wounded.

Licensed copies of the DC-3 were built in Japan as the Showa L2D (487 aircraft); and in the Soviet Union as the Lisunov Li-2 (4,937 aircraft).[11]

Thousands of surplus C-47s, previously operated by several air forces, were converted for civilian use after the war and became the standard equipment of almost all the world's airlines, remaining in frontline service for many years. The ready availability of cheap, easily maintained ex-military C-47s, both large and fast by the standards of the day, jumpstarted the worldwide postwar air transport industry. While aviation in prewar Continental Europe had used the metric system, the overwhelming dominance of C-47s and other U.S. war-surplus types cemented the use of nautical miles, knots and feet in postwar aviation throughout the world.

Douglas developed an improved version, the Super DC-3, with more engine power, greater cargo capacity and a different wing, but with all the bargain-priced surplus aircraft available, they did not sell well in the civil aviation market. Only five were delivered, three of them to Capital Airlines. The U.S. Navy had 100 of its early R4Ds converted to Super DC-3 standard during the early 1950s as the R4D-8, later C-117D. The last U.S. Navy C-117 was retired July 12, 1976.[22] The last U.S. Marine Corps C-117, serial 50835, was retired from active service during June 1982. Several remained in service with small airlines in North and South America in 2006.[23]

A number of aircraft companies attempted to design a "DC-3 replacement" over the next three decades (including the very successful Fokker F27 Friendship), but no single type could match the versatility, rugged reliability and economy of the DC-3. It remained a significant part of air transport systems well into the 1970s.

Douglas DC-3 today

A C-47A of Rovos Air in service in South Africa, 2006
This DC-3, operated as a warbird, previously flew for New Zealand's National Airways Corporation between two periods of service in the Royal New Zealand Air Force.
A DC-3 spinning its props

Perhaps unique among prewar aircraft, the DC-3 is in daily use. There are still small operators with DC-3s in revenue service and as cargo aircraft. The common saying among aviation enthusiasts and pilots is that "the only replacement for a DC-3 is another DC-3". The aircraft's legendary ruggedness is enshrined in the lighthearted description of the DC-3 as "a collection of parts flying in loose formation."[24] Its ability to use grass or dirt runways makes it popular in developing countries, where runways are not always paved.

Current uses of the DC-3 include aerial spraying, freight transport, passenger service, military transport, missionary flying, skydiver shuttling and sightseeing.

The very large number of civil and military operators of the DC-3/C-47s and related types makes a listing of all the airlines, air forces and other current operators impractical. As of 2012, DC-3 #10 is still used daily for flights in Colombia.[25] Buffalo Airways, based in Canada's Northwest Territories, operates a scheduled DC-3 passenger service between its main base in Yellowknife and Hay River, plus some passenger charter operations, using DC-3s. Some DC-3s are also used by the airline for cargo operations.[26]

The oldest surviving DST is N133D, the sixth Douglas Sleeper Transport built in 1936. This aircraft was delivered to American Airlines on July 12, 1936 as NC16005. The aircraft is at Shell Creek Airport (F13), Punta Gorda, Florida, where it is undergoing restoration. The aircraft will be restored to Douglas Sleeper Transport standards, and full airworthiness.[27]

The oldest DC-3 still flying is the original American Airlines Flagship Detroit (c/n 1920, #34 off the Santa Monica production line),[28] which can be seen at airshows around the United States and is owned and operated by the nonprofit Flagship Detroit Foundation.[18]

The base price of a new DC-3 in 1936 was around $60–80,000, and by 1960, used examples were available for $75,000.[29]

A 1943 DC-3 was installed as a major design element atop architectural renovations at The Roasterie in Kansas City, Missouri.[30]

Original operators

Variants

Fujairah Airlines DC-3 in the late 1960s
A 1944 Douglas DC-3C revving its engines
DST
Douglas Sleeper Transport, the initial variant with two Wright R-1820 Cyclone, standard sleeper accommodation for up to 16 with small upper windows,convertible to carry up to 24 day passengers.[31] Type Certificate ATC607. DST-A similar sleeper version with Pratt & Whitney R-1830 engines , ATC647
DC-3
Derived from DST with 21 day passenger seats , Wright R-1820 Cyclone engines,no sleeper berths, no upper windows. Type Certificate ATC618
DC-3A
As DC-3 but with two 1,200 hp (895 kW) Pratt & Whitney R-1830-21 radial piston engines. Type Certificate ATC619
DC-3B
Version of DC-3 with two Wright R-1820 Cyclone engines for TWA, smaller convertible sleeper cabin forward with fewer upper windows than DST. Type Certificate ATC635
DC-3C
Designation for ex-military C-47, C-53 and R4D aircraft rebuilt by Douglas Aircraft in 1946, given new manufacturer numbers and sold on the civil market, Pratt & Whitney R-1830 engines.[32] Type Certificate ATC669
DC-3D
Designation for 28 new aircraft completed by Douglas in 1946 with unused components from the cancelled USAAF C-117 production line.Pratt & Whitney R-1830 engines.[33] Type Certificate ATC669
TransNorthern Super DC-3 (C-117D) landing at Anchorage, Alaska in 2011
DC-3S
Super DC-3, substantially redesigned DC-3 with fuselage stretched by one frame, a new shape outer wings and distinctive tall squared tail, and fitted with more powerful Wright R-1820 Cyclone or Pratt & Whitney R-2000 engines. Five completed by Douglas for civil use using existing surplus secondhand airframes.[34] Three Super DC-3s were operated by Capital Airlines 1950-1952.[35] Designation also used for examples of the 100 R4Ds that had been converted by Douglas to this standard for the U.S. Navy as R4D-8s (later designated C-117Ds), all fitted with more powerful Wright R-1820 Cyclone engines, some of which entered civil use after retirement from the military.[36]
LXD1
A single DC-3 supplied for evaluation by the Imperial Japanese Navy Air Service.
A Nakajima L2D in U.S. markings captured in Mindanao and then transferred to Clark Field, Philippines, May 1945
C-41,C-41A
The Douglas C-41 was a single VIP DC-3 derivative(serial 38-502) supplied against order AC11137 for the narrower DC-2 derived C-39s,but powered by two 1,200 hp (895 kW) Pratt & Whitney R-1830-21 radial piston engines. (serial 38-502), for use by Air Corps Chief Westover (later used by USAAF General Hap Arnold).

The Douglas C-41A was a single VIP DC-3A (serial 40-070) supplied September 1939, powered by two 1,200 hp (895 kW) Pratt & Whitney R-1830-21 radial piston engines, used by the Secretary of War. The forward cabin converted to sleeper configuration with upper windows similar to the DC-3B .[37]

C-48
One former United Air Lines DC-3A impressed.
C-48A
Three impressed DC-3As with 18-seat interiors.
C-48B
Sixteen impressed former United Air Lines DST-As with 16-berth interior used as air ambulances.
C-48C
Sixteen impressed DC-3As with 21-seat interiors.
C-49
Various DC-3 and DST models, 138 impressed into service as C-49, C-49A, C-49B, C-49C, C-49D, C-49E, C-49F, C-49G, C-49H, C-49J, and C-49K.
C-50
Various DC-3 models, 14 impressed as C-50, C-50A, C-50B, C-50C and C-50D.
C-51
One aircraft ordered by Canadian Colonial Airlines impressed into service, had starboard-side door.
C-52
DC-3A aircraft with R-1830 engines, five impressed as C-52, C-52A, C-52B, C-52C and C-52D.
C-68
Two DC-3As impressed with 21-seat interiors.
C-84
One impressed DC-3B aircraft.
R4D-2
Two Eastern Air Lines DC-3s impressed into USN service as VIP transports, later designated R4D-2F and later R4D-2Z.
R4D-4
Ten impressed DC-3s for the US Navy.
R4D-4R
Seven impressed DC-3s as staff transports for the US Navy.
R4D-4Q
Radar countermeasures version of R4D-4 for the US Navy.
Dakota II
RAF designation for impressed DC-3s

Conversions

The only example of the Conroy Tri-Turbo-Three at the 1978 Farnborough Airshow. This aircraft saw service in both the Arctic and Antarctica
Airtech DC-3/2000
DC-3/C-47 engine conversion done by Airtech Canada, first offered in 1987. Powered by two PZL ASz-62IT radial engines.[38]
Basler BT-67
DC-3/C-47 conversion with a stretched fuselage, strengthened structure, modern avionics, and powered by two Pratt & Whitney Canada PT-6A-67R.
BSAS C-47TP Turbo Dakota
A South African C-47 conversion for the South African Air Force by Braddick Specialised Air Services, with two Pratt & Whitney Canada PT6A-65R turboprop engines, revised systems, stretched fuselage and modern avionics.
Conroy Turbo Three
One DC-3/C-47 converted by Conroy Aircraft with two Rolls-Royce Dart Mk. 510 turboprop engines.
Conroy Super-Turbo-Three
Same as the Turbo Three but converted from a Super DC-3. One converted.
Conroy Tri-Turbo-Three
One DC-3/C-47 converted by Conroy Aircraft with three Pratt & Whitney Canada PT-6A turboprops.
Greenwich Aircraft Corp Turbo Dakota DC-3
DC-3/C-47 conversion with a stretched fuselage, strengthened wing center section and updated systems; and powered by two Pratt & Whitney Canada PT6A-65AR turboprop engines.[39][40]
Ts-62
Douglas-built airframe fitted with Russian Shvetsov ASh-62IR radial engines after World War II due to shortage of American engines in the Soviet Union.
Ts-82
Similar to Ts-62, but with Shvetsov ASh-82FN radial engines of 1,650 hp.
USAC DC-3 Turbo Express
A turboprop conversion by the United States Aircraft Corporation, fitting Pratt & Whitney Canada PT6A-45R turboprop engines with an extended forward fuselage to maintain center of gravity. First flight of the prototype conversion, (N300TX), was on July 29, 1982.[41]

Military and foreign derivatives

Douglas C-47
Production military DC-3A variant.
Showa/Nakajima L2D
487 License built DC-3s and derivatives for the IJNAS.
Lisunov Li-2 / PS-84
4,937 DC-3 derivatives license-built in the USSR.

Accidents and incidents

Specifications (DC-3A)

Douglas DC-3
Cockpit of DC-3 formerly operated by the FAA to verify operation of navaids (VORs and NDBs) along federal airways

Data from McDonnell Douglas Aircraft since 1920[1]

General characteristics

Performance

Notable appearances in media

See also

Related development
Aircraft of comparable role, configuration and era
Related lists

References

Notes

  1. 1 2 Francillon 1979, pp. 217–251.
  2. Federal Reserve Bank of Minneapolis Community Development Project. "Consumer Price Index (estimate) 1800–". Federal Reserve Bank of Minneapolis. Retrieved October 21, 2016.
  3. Rumerman, Judy. "The Douglas DC-3." U.S. Centennial of Flight Commission, 2003. Retrieved March 12, 2012.
  4. "How the DC-3 Revolutionized Air Travel". Smithsonian.
  5. Jonathan Glancey. "BBC - Culture - The Douglas DC-3: Still revolutionary in its 70s".
  6. O'Leary 1992, p. 7.
  7. May, Joseph (8 January 2013). "Flagship Knoxville — an American Airlines Douglas DC-3". Hearst Seattle Media. Retrieved 3 August 2014.
  8. Berths were 77 inches (2.0 m) long; lowers were 36 in (91 cm) wide and uppers were 30 in (76 cm).
  9. Pearcy 1987, p. 17.
  10. O'Leary 2006, p. 54.
  11. 1 2 Gradidge 2006, p. 20.
  12. Turbo Dakota DC-3 Turbine Conversion Aircraft. dodson.com. Retrieved 12 September 2012.
  13. FAA Supplemental Type Certificate Number SA3820SW retrieved 28 March 2015
  14. Turbo Dakota DC-3 Conversion Process, Dodson International. Retrieved 28 March 2015
  15. "Basler BT-67". Basler Turbo Conversions, LLC via baslerturbo.com, 2008. Retrieved March 7, 2009.
  16. "BSAS International". www.bsasinternational.com. Retrieved October 11, 2011.
  17. Holden, Henry. "DC-3 History." dc3history.org. Retrieved October 7, 2010.
  18. 1 2 "DC-3." Flagship Detroit Foundation. Retrieved October 7, 2010.
  19. CNAC'S DC-2 1/2 Retrieved November 8, 2016.
  20. FlightGlobal archive (18 April 1953)
  21. FlightGlobal archive (14 November 1946)
  22. "The Seventies 1970–1980: C-117, p. 316." history.navy.mil. Retrieved August 10, 2010.
  23. Gradidge 2006, pp. 634–637.
  24. Williams, Michael. "How health and safety rules have grounded the Dakota, the war workhorse." Daily Mail, February 25, 2008. Retrieved March 7, 2009.
  25. "Colombia's Workhorse, the DC-3 airplane." Washington Post. Retrieved March 15, 2012.
  26. "Douglas DC-3." Buffalo Airways. Retrieved October 22, 2012.
  27. Moss, Frank. "World's Oldest DC-3." douglasdc3.com, 2011. Retrieved August 9, 2011.
  28. Pearcy 1985
  29. "The de Havilland Aircraft Co. Ltd." Flight, 18 November 1960, p. 798. Retrieved 12 September 2012.
  30. Myers, Keith. "1943 Plane installed atop KC coffee company." GlobalNe.Ws, 11 September 2012. Retrieved 12 November 2012.
  31. "Sleeping Car of the Air Has Sixteen Sleeping Berths." Popular Mechanics, January 1936.
  32. "Aircraft Specifications NO. A-669." FAA. Retrieved October 20, 2011.
  33. Gradidge 2006, pp. 632–633.
  34. Gradidge, 2006, p. 634
  35. Pearcy, Arthur Douglas Propliners DC-1 - DC-7, Shewsbury, England: Airlife Publishing Ltd., 1995, ISBN 1-8531026-1-X, pp. 93-95.
  36. Gradidge 2006, pp. 634–639.
  37. "Douglas C-41A." aero-web.org. Retrieved August 10, 2010.
  38. "AirTech Company Profile." ic.gc.ca. Retrieved November 22, 2009.
  39. Turbo Dakota DC-3 Conversion Process, Dodson International. Retrieved January 4, 2013
  40. Specs - Engines & Props, Dodson International. Retrieved January 4, 2013
  41. Taylor 1983

Bibliography

  • Francillon, René. McDonnell Douglas Aircraft Since 1920: Volume I. London: Putnam, 1979. ISBN 0-87021-428-4.
  • Gradidge, Jennifer M. The Douglas DC-1/DC-2/DC-3: The First Seventy Years, Volumes One and Two. Tonbridge, Kent, UK: Air-Britain (Historians) Ltd., 2006. ISBN 0-85130-332-3.
  • O'Leary, Michael. DC-3 and C-47 Gooney Birds. St. Paul, Minnesota: Motorbooks International, 1992. ISBN 0-87938-543-X.
  • O'Leary, Michael. "When Fords Ruled the Sky (Part Two)." Air Classics, Volume 42, No. 5, May 2006.
  • Pearcy, Arthur. Douglas DC-3 Survivors, Volume 1. Bourne End, Bucks, UK: Aston Publications, 1987. ISBN 0-946627-13-4.
  • Pearcy, Arthur. Douglas Propliners: DC-1–DC-7. Shrewsbury, UK: Airlife Publishing, 1995. ISBN 1-85310-261-X.
  • Taylor, John W. R. Jane's All the World's Aircraft, 1982–83. London: Jane's Publishing Company, 1983. ISBN 0-7106-0748-2.
  • Yenne, Bill. McDonnell Douglas: A Tale of Two Giants. Greenwich, Connecticut: Bison Books, 1985. ISBN 0-517-44287-6.
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