Editing Douglas DC-3 (section)

==Design and development==
[[File:PP-ANU (aircraft) 5.jpg|thumb|upright|DC-3 airliner cabin]]
[[File:DSTunitedOAK (4412476240).jpg|thumb|Douglas Sleeper Transport (DST) showing the second row of windows for the upper bunk beds, above the airline titles]]

"DC" stands for Douglas Commercial. The DC-3 was the culmination of a development effort that began after an inquiry from [[Trans World Airlines|Transcontinental and Western Airlines]] (TWA) to [[Donald Wills Douglas, Sr.|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.<ref>O'Leary 1992, p. 7.</ref> TWA asked Douglas to design and build an aircraft that would allow TWA to compete with United. Douglas' design, the 1933 [[Douglas DC-1|DC-1]], was promising, and led to the [[Douglas DC-2|DC-2]] in 1934. The DC-2 was a success, but with room for improvement.

[[File:Engine of Douglas DC-3.jpg|thumb|[[Wright R-1820 Cyclone]] 9 engine of American Airlines "Flagship Knoxville"<ref>{{cite news |last1=May |first1=Joseph |date=January 8, 2013 |title=Flagship Knoxville — an American Airlines Douglas DC-3 |publisher=Seattle Post-Intelligencer blogs |url=http://blog.seattlepi.com/travelforaircraft/2013/01/08/flagship-knoxville-%E2%80%94-an-american-airlines-douglas-dc-3/ |access-date=August 3, 2014 |archive-date=October 10, 2017 |archive-url=https://web.archive.org/web/20171010055621/http://blog.seattlepi.com/travelforaircraft/2013/01/08/flagship-knoxville-%e2%80%94-an-american-airlines-douglas-dc-3/ |url-status=dead}}</ref>]]
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 T-32 Condor II|Curtiss Condor II]] biplanes. The DC-2's cabin was {{convert|66|in|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 20 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) with Douglas chief test pilot [[Carl Cover]] at the controls. Its cabin was {{cvt|92|in}} wide, and a version with 21 seats instead of the 14–16 sleeping berths<ref>Berths were {{cvt|77|in|m}} long; lowers were {{cvt|36|in}} wide and uppers were {{cvt|30|in}}.</ref> of the DST was given the designation '''DC-3'''. No prototype was built, and the first DC-3 built followed seven DSTs off the production line for delivery to American Airlines.<ref>Pearcy 1987, p. 17.</ref>[[File:dc3.takeoff.thales.arp.jpg|thumb|Ex-military [[Air Atlantique]] [[Douglas C-47 Skytrain|C-47B]] at [[RAF Hullavington]] in 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, while westbound trips against the wind took {{Frac|17|1|2}} hours. A few years earlier, such a trip entailed short hops in slower and shorter-range aircraft during the day, [[Transcontinental Air Transport|coupled with train travel overnight]].<ref>O'Leary 2006, p. 54.</ref>

Several [[radial engine]]s were offered for the DC-3. Early-production civilian aircraft used either the 9-cylinder [[Wright R-1820 Cyclone|Wright R-1820 Cyclone 9]] or the 14-cylinder [[Pratt & Whitney R-1830 Twin Wasp]], but the Twin Wasp was chosen for most military versions and was also used by most DC-3s converted from military service. Five DC-3S ''Super DC-3s'' with [[Pratt & Whitney R-2000 Twin Wasp]]s were built in the late 1940s, three of which entered airline service.

===Production===
Total production including all military variants was 16,079.<ref name="Gradidge p. 20">Gradidge 2006, p. 20.</ref> More than 400 remained in commercial service in 1998. Production was:
* 607 civilian variants
* 10,048 military C-47 and C-53 derivatives built at [[Santa Monica, California]], [[Long Beach, California]], and [[Oklahoma City]]
* 4,937 built under license in the Soviet Union (1939–1950) as the [[Lisunov Li-2]] ([[NATO reporting name]]: '''Cab''')
* 487 [[Mitsubishi Kinsei]]-engined aircraft built by Showa and Nakajima in Japan (1939–1945), as the [[Showa/Nakajima L2D|L2D Type 0 transport]] (Allied codename '''Tabby''')

Production of DSTs ended in mid-1941 and civilian DC-3 production ended in early 1943, although dozens of the DSTs and DC-3s ordered by airlines that were produced between 1941 and 1943 were pressed into the US military service while still on the production line.<ref>Pearcy 1987, p. 76</ref><ref>Pearcy 1987, pp. 69–117</ref> 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 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 US Navy with the designation YC-129 alongside 100 R4Ds that had been upgraded to the Super DC-3 specifications.

===Turboprop conversions===
[[File:Ntps-c47-N834TP-071112-01cr-16.jpg|thumb|BSAS C-47–65ARTP powered by [[Pratt & Whitney Canada PT6|Pratt & Whitney Canada PT6-65AR]] turboprop engines]]
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]] or [[Pratt & Whitney PT6]]A [[turboprop|turbines]].

The Greenwich Aircraft Corp DC-3-TP is a conversion with an extended fuselage and with [[Pratt & Whitney Canada PT6|Pratt & Whitney Canada PT6A-65AR or PT6A-67R]] engines fitted.<ref>[http://www.dodson.com Turbo Dakota DC-3 "Turbine Conversion Aircraft"] {{Webarchive|url=https://web.archive.org/web/20180914073930/http://dodson.com/ |date=September 14, 2018}}. dodson.com. Retrieved September 12, 2012.</ref><ref>[http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/aca7e965b47f885785256cc2000c5ac4/$FILE/SA3820SW.pdf "FAA Supplemental Type Certificate Number SA3820SW"] {{Webarchive|url=https://web.archive.org/web/20161228045406/http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/aca7e965b47f885785256cc2000c5ac4/$FILE/SA3820SW.pdf |date=December 28, 2016}} retrieved March 28, 2015</ref><ref>[http://www.turbinedc3.com/conversion_process_turbine_dc3.html Turbo Dakota DC-3 Conversion Process] {{webarchive|url=https://web.archive.org/web/20140926233224/http://www.turbinedc3.com/conversion_process_turbine_dc3.html |date=2014-09-26}}, Dodson International. Retrieved March 28, 2015</ref>

The [[Basler BT-67]] is a conversion of the DC-3/C-47. Basler refurbishes C-47s and DC-3s at [[Wittman Regional Airport|Oshkosh]], [[Wisconsin]], fitting them with Pratt & Whitney Canada PT6A-67R turboprop engines, lengthening the fuselage by {{cvt|40|in}} with a fuselage plug ahead of the wing, and some local strengthening of the airframe.<ref>[http://www.baslerturbo.com/specifications.html "Basler BT-67"]. Basler Turbo Conversions, LLC via baslerturbo.com, 2008. Retrieved March 7, 2009.</ref>

South Africa-based Braddick Specialised Air Services International (commonly referred to as BSAS International) has also performed Pratt & Whitney PT6 turboprop conversions, having performed modifications on over 50 DC-3/C-47s / 65ARTP / 67RTP / 67FTPs.<ref>[https://archive.today/20130118152916/http://www.bsasinternational.com/index.php/turbine-aircraft Turbine Aircraft] Retrieved June 2, 2020.</ref>