Editing Douglas C-47 Skytrain (section)

==Design and development==
The C-47 differed from the civilian DC-3 by way of numerous modifications, including being fitted with a cargo door, hoist attachment and strengthened floor - along with a shortened tail cone for [[Military glider|glider-towing]] shackles, and an [[Astrodome (aeronautics)|astrodome]] in the cabin roof.<ref name="Wilson">Wilson, Stewart. ''Aircraft of WWII''. Fyshwick, ACT, Australia: Aerospace Publications Pty Ltd., 1998. {{ISBN|1-875671-35-8}}.</ref><ref>Parker 2013, pp. 37, 39, 45-47.</ref>

During World War II, the armed forces of many countries used the C-47 and modified DC-3s for the transport of troops, cargo, and wounded. The U.S. naval designation was R4D. More than 10,000 aircraft were produced in [[Long Beach, California|Long Beach]] and [[Santa Monica, California]], and [[Oklahoma City, Oklahoma]]. Between March 1943 and August 1945, the Oklahoma City plant produced 5,354 C-47s.<ref name="Parker, Dana T. pp. 13, 35"/><ref>Herman 2012, pp. 202-203, 227.</ref>

The specialized C-53 ''Skytrooper'' troop transport started production in October 1941 at Douglas Aircraft's Santa Monica plant. It lacked the cargo door, hoist attachment, and reinforced floor of the C-47. Only 380 aircraft were produced in all because the C-47 was found to be more versatile.

===Super DC-3 (R4D-8)===
{{main|Douglas R4D-8}}
[[File:C-117D Super Dakotas US Navy 1967.jpg|thumb|U.S. Navy C-117Ds at [[RAF Mildenhall]] in 1967]]

Large numbers of DC-3s and surplus C-47s were in commercial use in the United States in the 1940s. In response to proposed changes to the [[Federal Aviation Regulations|Civil Air Regulations]] airworthiness requirements that would limit the continuing use of these aircraft, Douglas offered a late-1940s DC-3 conversion to improve takeoff and single-engine performance. This new model, the DC-3S or "Super DC-3", was 39 in (0.99 m) longer. It allowed 30 passengers to be carried, with increased speed to compete with newer airliners. The rearward shift in the center of gravity led to larger tail surfaces and new outer, swept-back wings. More powerful engines were installed along with shorter, jet ejection-type exhaust stacks. These were either 1,475&nbsp;hp (1,100&nbsp;kW) [[Wright R-1820]] Cyclones or 1,450&nbsp;hp (1,081&nbsp;kW) [[Pratt & Whitney R-2000 Twin Wasp]]s in larger engine nacelles. Minor changes included wheel-well doors, a partially retractable tailwheel, flush rivets, and low-drag antenna. These all contributed to an increased top speed of {{convert|250|mph|km/h kn|abbr=on}}. With over 75% of the original DC-3/C-47 configuration changed, the modified design was virtually a new aircraft.<ref>[http://www.dc3history.org/dc3super.html "Super DC-3"] {{Webarchive|url=https://web.archive.org/web/20170721153357/http://www.dc3history.org/dc3super.html |date=21 July 2017 }}. dc3history.org. Retrieved 23 June 2010.</ref> The first DC-3S made its maiden flight on 23&nbsp;June 1949.<ref name="Frnc Doug p464-5">Francillon 1979, pp. 464–465.</ref>

The changes fully met the new FAR 4B airworthiness requirements, with significantly improved performance. However, little interest was expressed by commercial operators in the DC-3S. It was too expensive for the smaller operators that were its main target; only three were sold to [[Capital Airlines (United States)|Capital Airlines]]. The U.S. Navy and U.S. Marine Corps had 100 of their R4D aircraft modified to Super DC-3 standards as the R4D-8, later redesignated the C-117D.<ref name="Frnc Doug p466-7">Francillon 1979, pp. 466–467.</ref>