Editing Autogyro (section)

{{short description|Rotorcraft with unpowered rotor}}
{{Use dmy dates|date=September 2019}}
{{Use British English|date=February 2023}}

[[File:AutoGyro Calidus - Shuttleworth Season Premiere 2016 (26422815634).jpg|thumb|upright=1.36|A modern, closed-cabin, pusher-propeller autogyro in flight]]

An '''autogyro''' (from [[Ancient Greek|Greek]] {{wt|grc|αὐτός}} and {{wt|el|γύρος}}, "self-turning"), gyroscope, gyrocopter or '''gyroplane''', is a class of [[rotorcraft]] that uses an unpowered [[Helicopter rotor|rotor]] in free [[autorotation]] to develop [[lift (force)|lift]]. A [[gyroplane]] "means a rotorcraft whose rotors are not engine-driven, except for initial starting, but are made to rotate by action of the air when the rotorcraft is moving; and whose means of propulsion, consisting usually of conventional propellers, is independent of the rotor system."<ref>[https://www.ecfr.gov/current/title-14/chapter-I/subchapter-A/part-1]</ref> While similar to a [[helicopter rotor]] in appearance, the autogyro's unpowered rotor disc must have air flowing upward across it to make it rotate.

Forward [[thrust]] is provided independently, by an engine-driven [[propeller]].

It was originally named the '''''autogiro''''' by its Spanish inventor and engineer, [[Juan de la Cierva]], in his attempt to create an aircraft that could fly safely at low speeds. He first flew one on January 1923, at [[Cuatro Vientos Airport]] in [[Madrid]].<ref name="greg">{{citation |url = http://www.vectorsite.net/avheli_1.html#m4 |title = European Helicopter Pioneers |work = Air Vectors |last = Goebel |first = Greg |date = 1 Jun 2011 |url-status = usurped |archive-url = https://web.archive.org/web/20120205181430/http://www.vectorsite.net/avheli_1.html#m4 |archive-date = 5 February 2012 }}</ref> The aircraft resembled the [[fixed-wing aircraft]] of the day, with a front-mounted engine and propeller. The term {{em|Autogiro}} became  [[trademark]]ed by the [[Cierva Autogiro Company]]. De la Cierva's Autogiro is considered the predecessor of the modern [[helicopter]].<ref>{{cite book |author = George Galdorisi |title = Leave No Man Behind: The Saga of Combat Search and Rescue |url = https://books.google.com/books?id=T3HGfuFILuoC |publisher = Voyageur Press |isbn = 978-0-7603-2392-2 |year = 2008 |access-date = 8 November 2020 |archive-date = 25 February 2023 |archive-url = https://web.archive.org/web/20230225162720/https://books.google.com/books?id=T3HGfuFILuoC |url-status = live }}</ref><ref>{{cite book |author = Trevor Homer |title = The Book of Origins: The first of everything |url = https://books.google.com/books?id=J-eTGAAACAAJ |publisher = Hachette Digital |isbn = 978-1-405-51610-5 |year = 2007 |access-date = 8 November 2020 |archive-date = 25 February 2023 |archive-url = https://web.archive.org/web/20230225162721/https://books.google.com/books?id=J-eTGAAACAAJ |url-status = live }}</ref> The term '''''gyrocopter''''' (derived from helicopter) was used by E.{{nbsp}}Burke Wilford who developed the Reiseler Kreiser feathering rotor equipped {{em|gyroplane}} in the first half of the twentieth century. Gyroplane was later adopted as a trademark by [[Bensen Aircraft]].

The success of the Autogiro garnered the interest of [[Business magnate|industrialists]] and under license from de la Cierva in the 1920s and 1930s, the Pitcairn & Kellett companies made further innovations.<ref>{{Cite web |url = https://airandspace.si.edu/collection-objects/pitcairn-cierva-pca-1a/nasm_A19560048000 |title = Pitcairn-Cierva PCA-1A |institution = [[National Air and Space Museum]] |access-date = April 25, 2020 |archive-url = https://web.archive.org/web/20200425214205/https://airandspace.si.edu/collection-objects/pitcairn-cierva-pca-1a/nasm_A19560048000 |archive-date = April 25, 2020 |url-status = live }}</ref> Late-model autogyros patterned after [[Etienne Dormoy]]'s [[Buhl A-1 Autogyro]] and [[Igor Bensen]]'s designs feature a rear-mounted engine and propeller in a [[pusher configuration]].