Editing Fly-by-wire (section)

== History ==

[[File:Avro Arrow 04.jpg|thumb|right|[[Avro Canada CF-105 Arrow]], first non-experimental aircraft flown with a fly-by-wire control system]]

[[File:F-8C FBW.jpg|thumb|right|[[F-8 Crusader|F-8C Crusader]] digital fly-by-wire testbed]]

Servo-electrically operated control surfaces were first tested in the 1930s on the Soviet [[Tupolev ANT-20]].<ref>{{citation |url=http://www.tupolev.ru/russian/Show.asp?SectionID=163 |publisher=PSC "Tupolev" |title=One of the history page |archive-url= https://web.archive.org/web/20110110064230/http://tupolev.ru/Russian/Show.asp?SectionID=163|archive-date=10 January 2011 |language=ru <!-- quote: "На АНТ-20 впервые для тяжелого самолета в системе управления была применена жесткая трубчатая проводка, переставной стабилизатор с электродистанционной системен управления, электросервопривода в системе управления и в силовой установке." -->}}</ref> Long runs of mechanical and hydraulic connections were replaced with wires and electric servos.

In 1934, {{ill|Karl Otto Altvater|de}} filed a patent about the automatic-electronic system, which [[Landing flare|flared]] the aircraft, when it was close to the ground.<ref>Patent Hoehensteuereinrichtung zum selbsttaetigen Abfangen von Flugzeugen im Sturzflug, Patent Nr. DE619055 C vom 11. Januar 1934.</ref> In 1941, while being an engineer at [[Siemens]], developed and tested the first fly-by-wire system for the [[Heinkel He 111]], in which the aircraft was fully controlled by electronic impulses.<ref>The History of German Aviation Kurt Tank Focke-Wulfs Designer and Test Pilot by Wolfgang Wagner page 122.</ref>{{unreliable source?|date=January 2022}}

The first non-experimental aircraft that was designed and flown (in 1958) with a fly-by-wire flight control system was the [[Avro Canada CF-105 Arrow]],<ref>W. (Spud) Potocki, quoted in The Arrowheads, ''Avro Arrow: the story of the Avro Arrow from its evolution to its extinction'', pages 83–85. Boston Mills Press, Erin, Ontario, Canada 2004 (originally published 1980). {{ISBN|1-55046-047-1}}.</ref><ref name="Whitcomb">Whitcomb, Randall L. ''Cold War Tech War: The Politics of America's Air Defense''. Apogee Books, Burlington, Ontario, Canada 2008. Pages 134, 163. {{ISBN|978-1-894959-77-3}}</ref> a feat not repeated with a production aircraft (though the Arrow was cancelled with five built) until [[Concorde]] in 1969, which became the first fly-by-wire airliner. This system also included solid-state components and system redundancy, was designed to be integrated with a computerised navigation and automatic search and track radar, was flyable from ground control with data uplink and downlink, and provided artificial feel (feedback) to the pilot.<ref name=Whitcomb/>

The first electronic fly-by-wire testbed operated by the [[United States Air Force|U.S. Air Force]] was a [[Boeing B-47 Stratojet|Boeing B-47E Stratojet]] (Ser. No. 53-2280)<ref>{{cite web|url= https://www.nuclearmuseum.org/see/exhibits/operation-preservation/b-47e-stratojet-restoration|title=The National Museum of Nuclear Science & History Heritage Park|website= nuclearmuseum.org |language=en|access-date=2023-02-25}}</ref>

The first pure electronic fly-by-wire aircraft with no mechanical or hydraulic backup was the Apollo [[Lunar Landing Training Vehicle]] (LLTV), first flown in 1968.<ref name="LLRV">{{cite web|url=http://www.nasa.gov/centers/dryden/news/X-Press/50th_anniversary/top_20_projects/llrv.html|title=NASA – Lunar Landing Research Vehicle|website=nasa.gov|access-date=24 April 2018|archive-date=6 August 2016|archive-url=https://web.archive.org/web/20160806061836/http://www.nasa.gov/centers/dryden/news/X-Press/50th_anniversary/top_20_projects/llrv.html|url-status=dead}}</ref> This was preceded in 1964 by the [[Lunar Landing Research Vehicle]] (LLRV) which pioneered fly-by-wire flight with no mechanical backup.<ref>{{cite web|date=8 January 2011|title=1 NEIL_ARMSTRONG.mp4 (Part Two of Ottinger LLRV Lecture)|url=https://www.youtube.com/watch?v=lRBVJofGQyE&t=23m42s| archive-url=https://ghostarchive.org/varchive/youtube/20211211/lRBVJofGQyE| archive-date=2021-12-11 | url-status=live|access-date=24 April 2018|publisher=ALETROSPACE|via=YouTube}}{{cbignore}}</ref> Control was through a digital computer with three analog redundant channels. In the USSR, the [[Sukhoi T-4]] also flew. At about the same time in the United Kingdom a [[trainer aircraft|trainer]] variant of the British [[Hawker Hunter]] fighter was modified at the British [[Royal Aircraft Establishment]] with fly-by-wire flight controls<ref name="ElectricHunter">{{citation|title=RAE Electric Hunter|date=28 June 1973|url=http://www.flightglobal.com/pdfarchive/view/1973/1973%20-%201822.html|work=Flight International|page=1010|archive-url=https://web.archive.org/web/20160305165438/https://www.flightglobal.com/pdfarchive/view/1973/1973%20-%201822.html|archive-date=5 March 2016}}</ref> for the right-seat pilot.

In the UK the two seater [[Avro 707]]C was flown with a [[Fairey Aviation Company|Fairey]] system with mechanical backup<ref>{{citation |url=http://www.flightglobal.com/pdfarchive/view/1972/1972%20-%202032.html |title=Fairey fly-by-wire |work=Flight International |date=10 August 1972 |archive-url=https://web.archive.org/web/20160306090112/http://www.flightglobal.com/pdfarchive/view/1972/1972%20-%202032.html |archive-date=6 March 2016 }}</ref> in the early to mid-60s. The program was curtailed when the air-frame ran out of flight time.<ref name="ElectricHunter"/>

In 1972, the first digital fly-by-wire fixed-wing aircraft without a mechanical backup<ref>{{citation |url=http://www.flightglobal.com/pdfarchive/view/1973/1973%20-%202228.html |title=Fly-by-wire for combat aircraft |archive-url= https://web.archive.org/web/20181121181532/https://www.flightglobal.com/pdfarchive/view/1973/1973%20-%202228.html |archive-date=21 November 2018 |work=Flight International |date= 23 August 1973 |page=353}}</ref> to take to the air was an [[F-8 Crusader]], which had been modified electronically by [[NASA]] of the United States as a [[experimental aircraft|test aircraft]]; the F-8 used the [[Apollo Guidance Computer|Apollo guidance, navigation and control hardware]].<ref>{{citation |url=https://www.nasa.gov/wp-content/uploads/2021/09/120282main_FS-024-DFRC.pdf |title= F-8 Digital Fly-By-Wire Aircraft |publisher=nasa.gov |language=en |access-date=2024-02-19}}</ref>

The [[Airbus A320]] began service in 1988 as the first mass-produced airliner with digital fly-by-wire controls. As of June 2024, over 11,000 A320 family aircraft, variants included, are operational around the world, making it one of the best-selling commercial jets.<ref name=airbussales>{{cite web|url= https://www.airbus.com/en/products-services/commercial-aircraft/market/orders-and-deliveries|title= Orders and Deliveries|date= 3 April 2024|publisher= Airbus|access-date=2024-07-24}}</ref><ref name=FG170220>{{cite news |url= https://www.flightglobal.com/news/articles/analysis-how-a320-changed-the-world-for-commercial-433809/ |title= How A320 changed the world for commercial pilots |date= 20 February 2017 |work= Flight International |first= David |last=Learmount |access-date= 20 February 2017 |archive-url= https://web.archive.org/web/20170221110216/https://www.flightglobal.com/news/articles/analysis-how-a320-changed-the-world-for-commercial-433809/ |archive-date= 21 February 2017 |url-status = live}}</ref>

Boeing chose fly-by-wire flight controls for the 777 in 1994, departing from traditional cable and pulley systems. In addition to overseeing the aircraft's flight control, the FBW offered "[[Flight envelope|envelope protection]]", which guaranteed that the system would step in to avoid accidental mishandling, stalls, or excessive structural stress on the aircraft. The 777 used [[ARINC 629]] buses to connect primary flight computers (PFCs) with actuator-control electronics units (ACEs). Every PFC housed three 32-bit microprocessors, including a [[Motorola 68040]], an [[Intel 80486]], and an [[AMD Am29000|AMD 29050]], all programmed in [[Ada (programming language)|Ada]] programming language.<ref>{{Cite book |last1=Norris |first1=Guy |url=https://books.google.com/books?id=BxZgvgAACAAJ |title=Boeing 777: The Technological Marvel |last2=Wagner |first2=Mark |date=2001 |publisher=MBI |isbn=978-0-7603-0890-5 |language=en}}</ref>