{{Short description|Aircraft controls}} {{Use dmy dates|date=February 2022}} {{Use American English|date=February 2022}} [[File:BoeingControlYokes.jpg|thumb|right|Collection of control yokes at Boeing Future of Flight Museum: 747, 707, B-29, Trimotor. The former two yokes are W-shaped, while the latter two are circular.]]
A '''yoke''', alternatively known as a '''control wheel''' or a '''control column''', is a device used for piloting some fixed-wing aircraft.<ref name="Crane">Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 563. Aviation Supplies & Academics, 1997. {{ISBN|1-56027-287-2}}.</ref>
The pilot uses the yoke to control the attitude<!-- Note: the correct term is "attitude", not "altitude", please don't change it --> of the plane, usually in both pitch and roll. Rotating the control wheel controls the ailerons and the roll axis. Fore and aft movement of the control column controls the elevator and the pitch axis.<ref name="Crane" /> When the yoke is pulled back, the nose of the aircraft rises. When the yoke is pushed forward, the nose is lowered. When the yoke is turned left, the plane rolls to the left, and when it is turned to the right, the plane rolls to the right.
Small to medium-size aircraft, usually limited to propeller-driven, feature a mechanical system whereby the yoke is connected directly to the control surfaces with cables and rods. Human muscle power alone is not enough for larger and more powerful aircraft, so hydraulic systems are used, in which yoke movements control hydraulic valves and actuators. In more modern aircraft, inputs may first be sent to a fly-by-wire system, which then sends a corresponding signal to actuators attached to the aileron booster systems and control surfaces. Yokes may feature a stick shaker, which is designed to help indicate the onset of stall, or even a stick pusher, which physically pushes the yoke to prevent a stall.
==Styles== Yokes come in a variety of shapes and sizes, the most common being of a "U" or "W" design. Some aircraft use a "ram's horn" style yoke, shaped like an "M", such as Embraer aircraft and the Concorde. There are some rarer exotic or archaic styles, such as circular or semi-circular designs, much like a steering wheel.
In larger aircraft they are usually on a post protruding vertically from the floor, referred to as a control column. In most other planes, they are pivot point mounted on a horizontal tube that comes out of the instrument panel.
In the case of the Cirrus SR20 and Cirrus SR22, although the control looks like a side stick, it works like a yoke handle (referred to in the industry as a "side yoke").<ref>{{Cite news|url=https://www.flyingmag.com/aircraft/pistons/10-ways-sr22-changed-flying?page=0,0|title=10 Ways that the SR22 Changed Flying|work=Flying|access-date=2018-03-13|language=en|archive-date=21 August 2019|archive-url=https://web.archive.org/web/20190821141818/https://www.flyingmag.com/aircraft/pistons/10-ways-sr22-changed-flying/?page=0,0|url-status=dead}}</ref><ref>{{Cite news|url=https://www.flyhpa.com/2016/02/detailed-comparison-of-the-cessna-ttx-and-cirrus-sr22t-g5/|title=Detailed Comparison of the Cessna TTx and Cirrus SR22T G5 {{!}} High Performance Aviation, LLC|work=High Performance Aviation|access-date=2018-03-13}}</ref><ref>{{Cite news|url=http://www.pilotweb.aero/features/flight-tests/flight-test-g5-cirrus-sr22t-1-4858764|title=Flight Test: G5 Cirrus SR22T|work=Pilot|access-date=2018-03-13|language=en|archive-date=14 March 2018|archive-url=https://web.archive.org/web/20180314042923/http://www.pilotweb.aero/features/flight-tests/flight-test-g5-cirrus-sr22t-1-4858764|url-status=dead}}</ref> The Cessna 162 uses a similar device.<ref>{{Cite news|url=https://www.airspacemag.com/flight-today/flight-skycatcher-180952404/|title=A Flight In A Skycatcher|last=Larson|first=George C.|work=Air & Space Magazine|access-date=2018-05-19|language=en}}</ref><ref>{{Cite web|url=https://www.aopa.org/community/flying-clubs/flying-club-newsletter/2017/november/19/aircraft-spotlight|title=Aircraft Spotlight: The Cessna 162 Skycatcher - A Modern, Cost Effective Trainer|date=2017-11-19|website=www.aopa.org|access-date=2018-05-19}}</ref> <gallery mode="nolines"> File:ConcordeCockpitSinsheim.jpg|The cockpit of Concorde, which has an M-shaped yoke mounted on a control column File:Cabine do avião R99.jpg|The cockpit of an Embraer ERJ with an M-shaped yoke File:Pilotska kabina zrakoplova.JPG|"W"/"U" style yoke in a Cessna 152 light aircraft, mounted on a horizontal tube protruding from the instrumental panel File:Li-2 HA-LIX Cockpit 01.jpg|Circular, steering-wheel type yoke in a 1940s Lisunov Li-2 File:SR22TN Perspective Cockpit.jpg|Cirrus SR22 panel showing both side yokes File:Cessna 162 Skycatcher N5201K 0986 instrument panel.JPG|Cessna 162 Skycatcher instrument panel </gallery> ==Advantages and disadvantages== Side-sticks and centre-sticks are better for making rapid control inputs and dealing with high g-forces, hence their use in military, sport, and aerobatic aircraft. However, yokes are less sensitive (i.e., more precise) due to a larger range of motion and provide more visual feedback to the pilot.<ref name="Flying Magazine May 2008" >{{cite journal| last=Mc Clellan| first=J. Mac| date=May 2008| title=New Gulfstream, p. 52| journal=Flying Magazine| volume=135| issue=5| pages=52–57| url=https://books.google.com/books?id=XtHuMfT0BRQC| access-date=July 7, 2012 |quote=... sidesticks don't provide visual feedback and actually don't move much at all as they respond to the pressure applied by the human pilot ... in the G650 when you grab the yoke and move it, the one on the other side will respond just as it does on a conventional airplane.}}</ref>
Most yokes are connected and will both move together, thus providing instant indication to the other pilot when one makes a control input. This is in contrast to some fly-by-wire control sticks that allow each pilot to send different, and sometimes greatly conflicting, inputs. Competing inputs are signaled on Airbus craft.
Yokes take up more room than side-sticks in the cockpit and may even obscure some instruments; by comparison, side-sticks have minimal cockpit intrusion, allowing the inclusion of retractable tray-tables and making it easier to enter/leave small cockpits.<ref>[http://www.planeandpilotmag.com/proficiency/flight-training/learning-to-fly-in-a-cirrus-sr22.html "Learning To Fly In A Cirrus SR22"] {{Webarchive|url=https://web.archive.org/web/20160204085055/http://www.planeandpilotmag.com/proficiency/flight-training/learning-to-fly-in-a-cirrus-sr22.html |date=4 February 2016 }}. planeandpilotmag.com.</ref><ref>[http://www.flyingmag.com/pilot-technique/turbine-flying/gear-one-big-airplane "Gear Up: One Big Airplane Training in US Airways' newest A330 simulator"] {{Webarchive|url=https://web.archive.org/web/20160402145819/http://www.flyingmag.com/pilot-technique/turbine-flying/gear-one-big-airplane |date=2 April 2016 }}. flyingmag.com.</ref>
A yoke, unlike a side-stick, may be used comfortably with either hand. This can be useful if one needs to write or manipulate other controls in the cockpit. This advantage is shared with the center-stick.<ref name="Flying Magazine May 2008" />
==Ancillary functions== The yoke often incorporates other key functions such as housing thumb or finger buttons to enable the radio microphone, disengage the autopilot, and trim the aircraft. In addition, there may be a clipboard, checklist, or chronometer located in the yoke's center.<ref>[http://www.airliners.net/photo/Delta-Connection-(ASA/Canadair-CL-600-2B19-Regional/0133942/L/ Picture of the Canadair CL-600-2B19 Regional Jet CRJ-200ER aircraft]</ref><ref>[http://www.airliners.net/photo/USA---Air/Lockheed-C-130H-Hercules/1488750/L/ Picture of the Lockheed C-130H Hercules (L-382) aircraft]</ref><ref>[http://www.airliners.net/photo/Sun-Air/McDonnell-Douglas-DC-9-32/0515210/L/ Picture of the McDonnell Douglas DC-9-32 aircraft]</ref><ref>[http://www.airliners.net/photo/Beech-58-Baron/1322806/L/ Picture of the Beech 58 Baron aircraft]</ref>
==Alternative control systems== Yokes are not used on all aircraft. Airships use a ship's wheel, helicopters use a cyclic,<ref>[http://science.howstuffworks.com/transport/flight/modern/helicopter6.htm How Helicopters Work]</ref> and the majority of military fighter aircraft use a center or side-stick. Some light aircraft use a stick due to pilot preference. The latest Airbus family of passenger jets use a side-stick, similar to a joystick, to actuate control surfaces.<ref name=fbw_sidestick>{{cite web|url=http://www.airbus.com/innovation/proven-concepts/in-design/fly-by-wire/|title=Fly-by-wire - A CIVIL AVIATION FIRST|work=Airbus / Innovation / Proven concepts / In design / Fly-by-wire|publisher=Airbus|access-date=6 July 2012}}</ref><ref>{{Cite web |url=http://www.askcaptainlim.com/flying-the-plane-flying-90/164-flying-the-airbus-side-stick-the-one-with-the-fastest-thumb-wins.html |title=Flying the Airbus side stick - the one with the fastest thumb wins! |access-date=11 March 2011 |archive-date=18 February 2020 |archive-url=https://web.archive.org/web/20200218232454/http://www.askcaptainlim.com/flying-the-plane-flying-90/164-flying-the-airbus-side-stick-the-one-with-the-fastest-thumb-wins.html |url-status=dead }}</ref>
There are also computer input devices designed to simulate a yoke, intended for flight simulators.
==See also== * Index of aviation articles * Aircraft flight control system * HOTAS, an acronym for hands on throttle-and-stick * Rudder pedals
==References== {{Reflist}}
{{Aircraft components}} {{Flight instruments}}
{{DEFAULTSORT:Yoke (Aircraft)}} Category:Aircraft controls