Editing Circular wing

{{Short description|Disc-shaped wing}}
A '''circular wing''' is a disc-shaped [[wing]] having the outer planform of a circle.<ref>H. C. Levey and P. E. Wynter; [https://www.jstor.org/stable/2414154 "The Circular Wing and Related Problems"], ''Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences,'' Vol. 268, No. 1334 (Jul. 24, 1962), pp. 390-404.</ref>

If the [[aircraft]] has no fuselage or tail the disc-shaped craft is sometimes described as a ''flying saucer''. If the entire disc rotates it is called a ''disc wing''.

Disc-shaped aircraft development dates back to before [[World War II]].  A number of disc-shaped aircraft have been proposed over the years, and a few have been built.

==Circular wing aircraft==
===Nemeth Umbrella Plane===

In 1934, at [[Miami University]] (of Ohio), an aircraft called the [[Nemeth Parasol|Nemeth Umbrella Plane]] (aka Roundwing) was tested. (''Nemeth'' is sometimes spelled ''Nuneth''.) This aircraft had a [[parasol wing]] of circular form above a conventional fuselage and tail, and it was powered by propeller in a [[tractor configuration]].<ref>[http://www.aerofiles.com/_n.html Nemeth article] www.aerofiles.com</ref><ref>[http://www.aerofiles.com/nemeth.jpg photograph] www.aerofiles.com</ref>

===Sack AS.6===
During [[World War II]], a number of disc-shaped aircraft were proposed by aircraft designers in [[Germany]]. One of the few to make it further than the drawing board was the [[Sack AS-6]], an experimental light plane with a round-winged planform that first flew in 1944. The aircraft proved unsuccessful, and was scrapped in early 1945.<ref>J.Miranda/P.Mercado: Flugzeug Profile 23 - Deutsche Kreisflügelflugzeuge, Flugzeug Publikations GmbH, Illertissen 1995</ref>

===Vought Flying Flapjack===
{{main|Vought XF5U}}
During [[World War II|WWII]], [[Charles H. Zimmerman]] led a team at [[Vought|Chance-Vought]] that created a series of designs that eventually resulted in the [[Vought XF5U|Vought Flying Flapjack]],<ref name='Airpower'>[[Airpower]] magazine, July 2002, Volume 32, No. 4 pages 42 through 47.</ref> one of the first aircraft explicitly designed as a disc for aerodynamic reasons. The Flapjack had a large wing and very low [[wing loading]], allowing it to [[takeoff|take off]] easily from [[aircraft carrier]]s. As with the earlier [[Vought V-173]], the Flapjack's counter-rotating propellers were located at the ends of the wings to help counteract the drag-inducing vortices that would normally result from a wing of such a low [[Aspect ratio (wing)|aspect ratio]]. By the time the design was flying in the post-war era, [[jet engine]]s had rendered the design obsolete and the [[United States Navy|US Navy]] lost interest.
[[File:Vought XF5U.jpg|thumb|The Vought XF5U]]

In 1943, Boeing Aircraft built 3 scale model aircraft whose designs had saucer-shaped wings with a propeller in the front, and a rudder in the back. The cockpit was to be in front of the wings. There was no actual fuselage in the center. The aircraft model numbers were 390, 391, and 396.  They were to be powered by a Pratt & Whitney R-4360-3 Wasp Major radial engine and capable of reaching speeds of 414&nbsp;mph. They were intended to be fighter planes, armed with 4 20mm cannons and underwing [[hardpoint]]s that could carry {{convert|1134|kg|abbr=on}} bombs or external fuel tanks.  Boeing submitted the proposals to the US Navy.  The wing design had excellent [[short takeoff and landing]] (STOL) characteristics,{{Citation needed|date=August 2015}} that is preferred for fixed-wing aircraft carrier planes.  The Navy rejected the Boeing designs in favor of the similar-shaped Chance-Vought V-173/XF5U-1 aircraft.<ref name='Airpower'/><ref>[http://aerofiles.com/_boe.html Link to article on Boeing 390/391/396 with photograph] www.aerofiles.com</ref>

==Circular flying wings (flying saucers)==
===Avrocar===
{{main|Avro Canada VZ-9 Avrocar}}
[[File:Avrocar flying.jpg|thumb|The Avrocar under test]]
After the war, the [[Avro Canada]] company developed a saucer-shaped aircraft. [[John Carver Meadows Frost|John Frost]] became interested in the [[Coandă effect]] to produce lift, eventually designing a disc-shape in which the thrust was directed downward around the entire disc by a flap ringing the aircraft, allowing it to take off and land vertically. Once in flight, the flap would be angled slightly, producing a small thrust while being directed to the rear. Little lift would be generated by conventional means; the engine thus would instead be used to build an "artificial wing" by directing the airflow around the craft. He offered a number of increasingly dramatic performance estimates, generally claiming Mach 4 performance at {{convert|24000|m|ft|abbr=on}}, at which point the USAF took over funding under ''Weapon System 606A''. The result was a 29-foot (8.9 m) diameter supersonic ''Project Y2''.

Testing soon revealed that the entire concept was unworkable; the craft would be highly unstable at supersonic speed. Avro nevertheless continued work on the project as a subsonic design known as ''Project Silver Bug''. Silver Bug was of interest to the [[United States Army|US Army]], who was looking into solutions for battlefield transport and support, and they took over most of the project funding. The final outcome of Silver Bug was the [[VZ-9 AV Avrocar|Avrocar]] or ''VZ-9AV'', effectively (and unintentionally) a prototype [[hovercraft]] rather than an aircraft, which was made public in 1961.

===Lenticular missiles===
From the late 1950s the USA studied lenticular-shaped unmanned vehicles. These included the Lenticular Defense Missile (LDM) [[Pye Wacket]] and the nuclear bomb delivery [[Lenticular Reentry Vehicle]].

===Moller M200G Volantor===
[[File:Moller_M200X.jpg|thumb|The Moller M200G Volantor]]
{{Main|Moller M200G Volantor}}
The M200G Volantor is a prototype [[flying saucer]]-style [[hovercraft]], designed by aeronautics engineer [[Paul Moller]]. The M200G Volantor uses a system of eight computer-controlled [[ducted fan]]s to hover up to {{convert|10|ft|m|0}} above the ground.<ref name=Herald>{{Cite news |work=[[Herald Sun]] |title=Flying Jetsons come of age with hover pod |url=http://www.news.com.au/travel/story/0,23483,22208755-36335,00.html |access-date=2007-08-30 |first=John |last=Beveridge |date=2007-08-08 |url-status=dead |archiveurl=https://web.archive.org/web/20070918201607/http://www.news.com.au/travel/story/0%2C23483%2C22208755-36335%2C00.html |archivedate=2007-09-18 }}</ref> Volantor is a term coined by Moller meaning "a [[VTOL|vertical takeoff and landing]] aircraft".

==Disc wing==
{{For|Disc-winged bats|Thyropteridae}}
A disc wing is a circular wing that spins. It is mostly used for [[flying disc]] toys.<ref>Potts, J.R.; [http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569224 Disc-wing aerodynamics], University of Manchester, 2005.</ref>

==See also==
*[[Aeroshell]]
*[[Ring wing]]
*[[Ufology]]

==References==
===Citations===
{{reflist}}

===Bibliography===
*''[[U.S. News & World Report]]'', April 7, 1950; article on experimental US disc-shaped aircraft that can hover like a helicopter and speed up like a jet.
*[[Weekly Reader|''My Weekly Reader'']], October 12, 1950, "Military secret of the United States of America Air Forces", (flying saucers are US Air Force experimental aircraft).
*''[[Popular Mechanics]]'', January 1995; "Flying Saucers Are Real", (real aircraft from the planet Earth).
* Rose, Bill; Tony Buttler. ''Secret Projects: Flying Saucer Aircraft'',  Midland Publishing, 2004 {{ISBN|978-1-85780-233-7}}

==External links==
*[http://www.rexresearch.com/wingless/wingless.htm List of disc-shaped aircraft patents]
*[http://www.project1947.com/fig/sb/page_1.htm 1955 declassified technical report on Project Y2 for Project Silver Bug]
*[http://www.daviddarling.info/encyclopedia/A/Avrocar.html Avrocar]
*[http://www.luft46.com/misc/sackas6.html The Sack AS-6, a circular experimental aircraft from WW2 Germany]
*[https://www.wired.com/science/discoveries/news/2003/12/61681 Flying Saucer May Yet Take Flight-- the EKIP]

[[Category:Circular-wing aircraft| ]]
[[Category:Wing configurations]]