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A side-stick or sidestick controller is an aircraft control stick that is located on the side console of the pilot, usually on the righthand side, or outboard on a two-seat flightdeck. Typically this is found in aircraft that are equipped with fly-by-wire control systems.^[1]

The throttle controls are typically located to the left of a single pilot or centrally on a two-seat flightdeck. Only one hand is required to operate them; two handed operation is neither possible nor necessary.

Prevalence

The side-stick is used in many modern military fighter aircraft, such as the F-16 Fighting Falcon, Mitsubishi F-2, Dassault Rafale, and F-22 Raptor, F-35 Lightning 2, Chengdu J-20, AIDC F-CK 1 Ching-Kuo and also on civil aircraft, such as the Sukhoi Superjet 100, Airbus A320 and all subsequent Airbus aircraft,^[2] including the largest passenger jet in service, the Airbus A380.

It is also used in new helicopter models such as the Bell 525.

Compared to centre sticks

A side-stick arrangement contrasts with the more conventional design where the stick is located in the centre of the cockpit between the pilot's legs, called a "centre stick". A side-stick arrangement allows HOTAS and increases ejection seat safety for the pilot as there is less interference amongst flight controls.^{[citation needed]}

Comparison of passive and active side-sticks

Passive side-sticks

In the centre stick design, like traditional airplane yokes, both the pilot flying, PF's, and pilot not flying, PNF's, controls are mechanically connected together so each pilot has a sense of the control inputs of the other.

In typical Airbus aircraft, the side-sticks are passive and move independently from each other; the side-stick does not offer any haptic feedback on what the other pilot is inputting. In Airbus' implementation, input values of both side-sticks are normally added up^[3], except when the "priority takeover button" is held down. In such a scenario, any inputs on the other side-stick will be ignored.^[4] Holding this button down for a minimum of 40 seconds will result in the other side-stick being disabled. This can reversed by pressing the button on either side-stick again. A green light will activate on the side of the pilot currently on control. In contrast, on the side of the other pilot, a red light will turn on to indicate that their side-stick's inputs are being ignored.^[5]

While the inputs are added up, the sum is clamped to the value of the maximum possible deflection a single side-stick^[6]; but this still means that when both side-stick are deflected 50% in the same direction, the resulting effective input will be that of a fully deflected side-stick, despite neither one being deflected over 50%. In addition, because the inputs are added up, any deflection of the other side-stick in the opposite direction will in effect be subtracted, resulting in the inputs partially cancelling each other out. In fact, if two inputs have opposite directions but equal magnitudes, the sum will be zero, and thus the flight control surfaces would remain in their current positions.

In addation to visual indications^[7], detection of more than a single side-stick deflection greater than 2°^[8] from neutral without the priority takeover button being held down results in an aural "DUAL INPUT" warning being played every five seconds.^[9] Due to this aural warning having the lowest priority, it will not be played if there are warnings with a higher priority, such as those from the EGPWS, as those will take precedence^[10], posing a potential risk for pilots. Examples of this occurring include the 2009 crash of Air France Flight 447 (an Airbus A330 flying from Rio de Janeiro to Paris), the 2010 crash of Afriqiyah Airways Flight 771 an Airbus A330 from flying Johannesburg to Tripoli^[11]^[12] and the 2014 crash of Indonesia AirAsia Flight 8501 (an Airbus A320 flying from Surabaya to Singapore).^[13]^[14] The "dual input" warning will not activate at very low levels if the EGPWS activates due to its lower priority compared to EGPWS.^[15]

Active side-sticks

However a later, significant, development is the 'active' side-stick,^[16] which is in the new Gulfstream G500/G600 series business jet aircraft. In this system, movements in one side-stick produce the same actions in the other side-stick and therefore provides valuable feedback to the other pilot. This addresses the earlier criticisms of the 'passive' side-stick. The 'active' side-stick also provides tactile feedback^[17] to the pilot during manual flight. In fact the three largest avionics manufacturers, Honeywell, Rockwell Collins and Thales,^[18] believe it will become the standard for all new fly-by-wire aircraft. In 2015 Ratier-Figeac as a subsidiary of UTC Aerospace Systems, and supplier of ‘passive’ side-sticks to Airbus since the 1980s^[19] became the supplier of ‘active’ side-sticks for the Irkut MC-21.^[20] This is the first airliner to use them.

Such an active side-stick can also be used to increase adherence to a safe flight envelope by applying a force feedback when the pilot makes a control input that would bring the aircraft closer to (or beyond) the borders of the safe flight envelope. This reduces the risk of pilots entering dangerous states of flights outside the operational borders while maintaining the pilots' final authority and increasing their situation awareness.^[21]

References

^ Crane, Dale: Dictionary of Aeronautical Terms, third edition, page 463. Aviation Supplies & Academics, 1997. ISBN 1-56027-287-2
^ "Fly-by-wire - A CIVIL AVIATION FIRST". Airbus / Innovation / Proven concepts / In design / Fly-by-wire. Airbus. Archived from the original on 8 July 2012. Retrieved 6 July 2012.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. The two sidesticks are not mechanically linked as they are on older types of aircraft. This means that both sticks may be operated independently one of the other. When one sidestick is operated it sends an electrical signal to the Fly By Wire computers. When both sticks are moved simultaneously, the system adds the signals of both pilots algebraically.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. To avoid both signals being added by the system, a priority P/B is provided on each stick. By pressing this button, a pilot may cancel the inputs of the other pilot. An audio signal will indicate which sidestick has priority.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. A green light will come on in front of the pilot who has taken control if the other stick is not in neutral popsition, and a red light comes on in front of the pilot whose stick is deactivated.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. The total is limited to the signal that would result from the maximum deflection of a single sidestick.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. When a dual input situation is detected, the two green priority lights located on the cockpit front panel flash simultaneously. The visual indication is an ADVISORY of a dual input situation
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. In order to warn the crew in case of dual sidestick operations, Airbus has designed a package of dual input indicators and audio warning. These operate when both side sticks are deflected simultaneously by more than 2°.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. After the visual indication has been triggered, a synthetic voice "DUAL INPUT" comes up every 5 sec, as long as the dual input condition persists. The synthetic voice is a WARNING of a dual input situation.
^ "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. Note: This audio has the lowest priority among the synthetic voice audio alerts.
^ Ranter, Harro. "ASN Aircraft accident Airbus A330-202 5A-ONG Tripoli International Airport (TIP)". aviation-safety.net.
^ Page 81 "Conclusions" Final Report of AFRIQIYAH Airways Aircraft, Airbus A330-202, 5A-ONG Crash, Occurred at Tripoli (LIBYA)on 12/05/2010 Published February 2013.
^ "Is Flight 447's 'Fly-by-Wire' Aircraft Technology Safe?". Fox News. 2009-06-12. Retrieved 2013-05-29.
^ Ross, Nick (2012-04-28), "Air France Flight 447: 'Damn it, we're going to crash'", The Daily Telegraph (article), It seems surprising that Airbus has conceived a system preventing one pilot from easily assessing the actions of the colleague beside him. And yet that is how their latest generations of aircraft are designed. The reason is that, for the vast majority of the time, side-sticks are superb.
^ Final Report on the investigation into the accident involving the Armavia A320 near Sochi Airport on 3 May 2006, page 48, Published 12 February 2007
^ "Commercial Active Sticks - An Active Role". BAE Systems | International. Retrieved 2019-08-10.
^ "BAE Brochure" (PDF).
^ Dubois, Thierry (29 June 2015). "Cockpits of the Future". Skies magazine. Archived from the original on 6 February 2021. Retrieved 6 February 2021.
^ https://www.youtube.com/watch?v=3sXXx8rgeeE, How Collins Active Control Sidesticks Work – Aviation International News Aug 13, 2019
^ https://www.flightglobal.com/mc-21-ushers-active-sidesticks-into-commercial-aircraft-cockpits/116609.article MC-21 ushers active sidesticks into commercial aircraft cockpits By Stephen Trimble 22 April 2015.
^ Florian J. J. Schmidt-Skipiol & Peter Hecker (2015). "Tactile Feedback and Situation Awareness-Improving Adherence to an Envelope in Sidestick-Controlled Fly-by-Wire Aircrafts.[sic]". 15th AIAA Aviation Technology, Integration, and Operations Conference: 2905. doi:10.2514/6.2015-2905. ISBN 978-1-62410-369-8.

External links

Formation stick from Popular Science 1945.

[Crane-1] Crane, Dale: Dictionary of Aeronautical Terms, third edition, page 463. Aviation Supplies & Academics, 1997. ISBN 1-56027-287-2

[fbw_sidestick-2] "Fly-by-wire - A CIVIL AVIATION FIRST". Airbus / Innovation / Proven concepts / In design / Fly-by-wire. Airbus. Archived from the original on 8 July 2012. Retrieved 6 July 2012.

[3] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. The two sidesticks are not mechanically linked as they are on older types of aircraft. This means that both sticks may be operated independently one of the other. When one sidestick is operated it sends an electrical signal to the Fly By Wire computers. When both sticks are moved simultaneously, the system adds the signals of both pilots algebraically.

[4] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. To avoid both signals being added by the system, a priority P/B is provided on each stick. By pressing this button, a pilot may cancel the inputs of the other pilot. An audio signal will indicate which sidestick has priority.

[5] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. A green light will come on in front of the pilot who has taken control if the other stick is not in neutral popsition, and a red light comes on in front of the pilot whose stick is deactivated.

[6] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. The total is limited to the signal that would result from the maximum deflection of a single sidestick.

[7] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. When a dual input situation is detected, the two green priority lights located on the cockpit front panel flash simultaneously. The visual indication is an ADVISORY of a dual input situation

[8] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. In order to warn the crew in case of dual sidestick operations, Airbus has designed a package of dual input indicators and audio warning. These operate when both side sticks are deflected simultaneously by more than 2°.

[9] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. After the visual indication has been triggered, a synthetic voice "DUAL INPUT" comes up every 5 sec, as long as the dual input condition persists. The synthetic voice is a WARNING of a dual input situation.

[10] "Dual Side Stick Inputs" (PDF). Airbus Safety First #03 December 2006 p. 5/5. Airbus Safety First Magazine. 2024-11-23. Note: This audio has the lowest priority among the synthetic voice audio alerts.

[11] Ranter, Harro. "ASN Aircraft accident Airbus A330-202 5A-ONG Tripoli International Airport (TIP)". aviation-safety.net.

[12] Page 81 "Conclusions" Final Report of AFRIQIYAH Airways Aircraft, Airbus A330-202, 5A-ONG Crash, Occurred at Tripoli (LIBYA)on 12/05/2010 Published February 2013.

[13] "Is Flight 447's 'Fly-by-Wire' Aircraft Technology Safe?". Fox News. 2009-06-12. Retrieved 2013-05-29.

[Ross-14] Ross, Nick (2012-04-28), "Air France Flight 447: 'Damn it, we're going to crash'", The Daily Telegraph (article), It seems surprising that Airbus has conceived a system preventing one pilot from easily assessing the actions of the colleague beside him. And yet that is how their latest generations of aircraft are designed. The reason is that, for the vast majority of the time, side-sticks are superb.

[15] Final Report on the investigation into the accident involving the Armavia A320 near Sochi Airport on 3 May 2006, page 48, Published 12 February 2007

[16] "Commercial Active Sticks - An Active Role". BAE Systems | International. Retrieved 2019-08-10.

[17] "BAE Brochure" (PDF).

[18] Dubois, Thierry (29 June 2015). "Cockpits of the Future". Skies magazine. Archived from the original on 6 February 2021. Retrieved 6 February 2021.

[19] ttps://www.youtube.com/watch?v=3sXXx8rgeeE, How Collins Active Control Sidesticks Work – Aviation International News Aug 13, 2019

[20] ttps://www.flightglobal.com/mc-21-ushers-active-sidesticks-into-commercial-aircraft-cockpits/116609.article MC-21 ushers active sidesticks into commercial aircraft cockpits By Stephen Trimble 22 April 2015.

[21] Florian J. J. Schmidt-Skipiol & Peter Hecker (2015). "Tactile Feedback and Situation Awareness-Improving Adherence to an Envelope in Sidestick-Controlled Fly-by-Wire Aircrafts.[sic]". 15th AIAA Aviation Technology, Integration, and Operations Conference: 2905. doi:10.2514/6.2015-2905. ISBN 978-1-62410-369-8.

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@@ Line 1: / Line 1: @@
 {{Short description|Aircraft control}}
 {{Redirect|Side stick||Rimshot (disambiguation)}}
-[[File:Airbus A380 cockpit.jpg|thumb|[[Airbus A380]] flight deck with black side-sticks on the left side of the left seat and on the right side of the right seat. The throttle controls in the central console are black, labeled 1-4.]]
+[[File:Airbus A380 cockpit.jpg|thumb|[[Airbus A380]] flight deck with black side-sticks on the left side of the left seat and on the right side of the right seat. The throttle controls in the central console are black, labeled 1–4.]]
-[[File:F-16D cockpit at EFKA.jpg|thumb|F-16 cockpit showing side-stick]]
+[[File:F-16D cockpit at EFKA.jpg|thumb|[[F-16]] cockpit showing side-stick]]
 A '''side-stick''' or '''sidestick controller''' is an [[aircraft]] control stick that is located on the side console of the [[Aviator|pilot]], usually on the righthand side, or outboard on a two-seat [[Cockpit (aviation)|flightdeck]]. Typically this is found in aircraft that are equipped with [[fly-by-wire]] control systems.<ref name="Crane">Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 463. Aviation Supplies & Academics, 1997. {{ISBN|1-56027-287-2}}</ref>
-The throttle controls are typically located to the left of a single pilot or centrally on a two-seat flightdeck. Only one hand is required to operate it; two hand operation is neither possible nor necessary.
+The throttle controls are typically located to the left of a single pilot or centrally on a two-seat flightdeck. Only one hand is required to operate them; two handed operation is neither possible nor necessary.
 == Prevalence ==
-The side-stick is used in many modern military [[fighter aircraft]], such as the [[F-16 Fighting Falcon]], [[Mitsubishi F-2]], [[Dassault Rafale]], and [[F-22 Raptor]], and also on civil aircraft, such as the [[Sukhoi Superjet 100]], [[Airbus A320]] and all subsequent [[Airbus]] aircraft,<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 |url-status = dead |archive-url = https://web.archive.org/web/20120708070059/http://www.airbus.com/innovation/proven-concepts/in-design/fly-by-wire/ |archive-date = 8 July 2012}}</ref> including the largest passenger jet in service, the [[Airbus A380]].
+The side-stick is used in many modern military [[fighter aircraft]], such as the [[F-16 Fighting Falcon]], [[Mitsubishi F-2]], [[Dassault Rafale]], and [[F-22 Raptor]], [[Lockheed Martin F-35 Lightning II|F-35 Lightning 2]], [[Chengdu J-20]], [[AIDC F-CK-1 Ching-kuo|AIDC F-CK 1 Ching-Kuo]] and also on civil aircraft, such as the [[Sukhoi Superjet 100]], [[Airbus A320]] and all subsequent [[Airbus]] aircraft,<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 |url-status = dead |archive-url = https://web.archive.org/web/20120708070059/http://www.airbus.com/innovation/proven-concepts/in-design/fly-by-wire/ |archive-date = 8 July 2012}}</ref> including the largest passenger jet in service, the [[Airbus A380]].
 It is also used in new helicopter models such as the [[Bell 525 Relentless|Bell 525]].
@@ Line 18: / Line 18: @@
 == Comparison of passive and active side-sticks ==
 === Passive side-sticks ===
+In the centre stick design, like traditional [[Yoke (aeronautics)|airplane yokes]], both the pilot flying, PF's, and pilot not flying, PNF's, controls are mechanically connected together so each pilot has a sense of the control inputs of the other.
-In the centre stick design, like traditional [[Yoke (aeronautics)|airplane yokes]], both the pilot's and co-pilot's controls are mechanically connected together so each pilot has a sense of the control inputs of the other. In typical Airbus side-stick implementations, the sticks are independent, the so-called 'passive' side-stick. The plane's computer either aggregates multiple inputs or a pilot can press a "priority button" to lock out inputs from the other side-stick.<ref name=getline>{{citation | last = Getline | first = Meryl | author-link = Meryl Getline | title = Ask the captain | journal = USA Today | date = 2005-11-21 | url = https://www.usatoday.com/travel/columnist/getline/2005-11-21-ask-the-captain_x.htm}}</ref> However, if both side-sticks are moved in different directions at the same time (regardless of which pilot has priority), then both inputs are cancelled out and an aural "dual input" warning sounds. Examples of this occurring include the 2009 crash of [[Air France Flight 447]] (an [[Airbus A330]] flying from [[Rio de Janeiro]] to [[Paris]]), the 2010 crash of [[Afriqiyah Airways Flight 771]] an Airbus A330 from flying [[Johannesburg]] to [[Tripoli, Libya|Tripoli]]<ref>{{Cite web|url=https://aviation-safety.net/database/record.php?id=20100512-0|title=ASN Aircraft accident Airbus A330-202 5A-ONG Tripoli International Airport (TIP)|first=Harro|last=Ranter|website=aviation-safety.net}}</ref><ref>Page 81 "Conclusions" [https://reports.aviation-safety.net/2010/20100512-0_A332_5A-ONG.pdf Final Report of AFRIQIYAH Airways Aircraft, Airbus A330-202, 5A-ONG Crash], Occurred at Tripoli (LIBYA)on 12/05/2010 Published February 2013.</ref> and the 2014 crash of [[Indonesia AirAsia Flight 8501]] (an [[Airbus A320]] flying from [[Surabaya]] to [[Singapore]]).<ref>{{cite web|url=http://www.foxnews.com/story/2009/06/12/is-flight-447-fly-by-wire-aircraft-technology-safe/|title=Is Flight 447's 'Fly-by-Wire' Aircraft Technology Safe?|date=2009-06-12|publisher=Fox News|access-date=2013-05-29}}</ref><ref name="Ross">{{Citation|last=Ross|first=Nick|title=Air France Flight 447: 'Damn it, we're going to crash'|date=2012-04-28|url=https://www.telegraph.co.uk/technology/9231855/Air-France-Flight-447-Damn-it-were-going-to-crash.html|quote=It seems surprising that Airbus has conceived a system preventing one pilot from easily assessing the actions of the colleague beside him. And yet that is how their latest generations of aircraft are designed. The reason is that, for the vast majority of the time, side-sticks are superb.|type=article|newspaper=[[The Daily Telegraph]]}}</ref> The "dual input" warning will not activate at very low levels if the [[Ground proximity warning system|EGPWS]] activates due to its lower priority compared to EGPWS.<ref>[https://www.bea.aero/docspa/2006/ek-9060502/pdf/ek-9060502.pdf Final Report on the investigation into the accident involving the Armavia A320 near Sochi Airport on 3 May 2006], page 48, Published 12 February 2007</ref>
+In typical Airbus aircraft, the side-sticks are passive and move independently from each other; the side-stick does not offer any haptic feedback on what the other pilot is inputting. In Airbus' implementation, input values of both side-sticks are normally added up<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "The two sidesticks are not mechanically linked as they are on older types of aircraft. This means that both sticks may be operated independently one of the other. When one sidestick is operated it sends an electrical signal to the Fly By Wire computers. When both sticks are moved simultaneously, the system adds the signals of both pilots algebraically."}}</ref>, except when the "priority takeover button" is held down. In such a scenario, any inputs on the other side-stick will be ignored.<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "To avoid both signals being added by the system, a priority P/B is provided on each stick. By pressing this button, a pilot may cancel the inputs of the other pilot. An audio signal will indicate which sidestick has priority."}}</ref> Holding this button down for a minimum of 40 seconds will result in the other side-stick being disabled. This can reversed by pressing the button on either side-stick again. A green light will activate on the side of the pilot currently on control. In contrast, on the side of the other pilot, a red light will turn on to indicate that their side-stick's inputs are being ignored.<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | quote = "A green light will come on in front of the pilot who has taken control if the other stick is not in neutral popsition, and a red light comes on in front of the pilot whose stick is deactivated." | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf}}</ref>
+While the inputs are added up, the sum is [[clamp (function)|clamped]] to the value of the maximum possible deflection a single side-stick<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "The total is limited to the signal that would result from the maximum deflection of a single sidestick."}}</ref>; but this still means that when both side-stick are deflected 50% in the same direction, the resulting effective input will be that of a fully deflected side-stick, despite neither one being deflected over 50%. In addition, because the inputs are added up, any deflection of the other side-stick in the opposite direction will in effect be subtracted, resulting in the inputs partially cancelling each other out. In fact, if two inputs have opposite directions but equal magnitudes, the sum will be zero, and thus the flight control surfaces would remain in their current positions.
+In addation to visual indications<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "When a dual input situation is detected, the two green priority lights located on the cockpit front panel flash simultaneously. The visual indication is an ADVISORY of a dual input situation"}}</ref>, detection of more than a single side-stick deflection greater than 2°<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "In order to warn the crew in case of dual sidestick operations, Airbus has designed a package of dual input indicators and audio warning. These operate when both side sticks are deflected simultaneously by more than 2°."}}</ref> from neutral without the priority takeover button being held down results in an aural "DUAL INPUT" warning being played every five seconds.<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "After the visual indication has been triggered, a synthetic voice “DUAL INPUT” comes up every 5 sec, as long as the dual input condition persists. The synthetic voice is a WARNING of a dual input situation."}}</ref> Due to this aural warning having the lowest priority, it will not be played if there are warnings with a higher priority, such as those from the [[Ground proximity warning system|EGPWS]], as those will take precedence<ref>{{cite web | work = Airbus Safety First #03 December 2006 p. 5/5 | series = Airbus Safety First Magazine | title = Dual Side Stick Inputs | date = 2024-11-23 | url =
+https://safetyfirst.airbus.com/app/themes/mh_newsdesk/documents/archives/dual-side-stick-inputs.pdf | quote = "Note: This audio has the lowest priority among the synthetic voice audio alerts."}}</ref>, posing a potential risk for pilots.
+Examples of this occurring include the 2009 crash of [[Air France Flight 447]] (an [[Airbus A330]] flying from [[Rio de Janeiro]] to [[Paris]]), the 2010 crash of [[Afriqiyah Airways Flight 771]] an Airbus A330 from flying [[Johannesburg]] to [[Tripoli, Libya|Tripoli]]<ref>{{Cite web|url=https://aviation-safety.net/database/record.php?id=20100512-0|title=ASN Aircraft accident Airbus A330-202 5A-ONG Tripoli International Airport (TIP)|first=Harro|last=Ranter|website=aviation-safety.net}}</ref><ref>Page 81 "Conclusions" [https://reports.aviation-safety.net/2010/20100512-0_A332_5A-ONG.pdf Final Report of AFRIQIYAH Airways Aircraft, Airbus A330-202, 5A-ONG Crash], Occurred at Tripoli (LIBYA)on 12/05/2010 Published February 2013.</ref> and the 2014 crash of [[Indonesia AirAsia Flight 8501]] (an [[Airbus A320]] flying from [[Surabaya]] to [[Singapore]]).<ref>{{cite web|url=https://www.foxnews.com/story/is-flight-447s-fly-by-wire-aircraft-technology-safe/|title=Is Flight 447's 'Fly-by-Wire' Aircraft Technology Safe?|date=2009-06-12|publisher=Fox News|access-date=2013-05-29}}</ref><ref name="Ross">{{Citation|last=Ross|first=Nick|title=Air France Flight 447: 'Damn it, we're going to crash'|date=2012-04-28 |url=https://www.telegraph.co.uk/technology/9231855/Air-France-Flight-447-Damn-it-were-going-to-crash.html|quote=It seems surprising that Airbus has conceived a system preventing one pilot from easily assessing the actions of the colleague beside him. And yet that is how their latest generations of aircraft are designed. The reason is that, for the vast majority of the time, side-sticks are superb.|type=article|newspaper=[[The Daily Telegraph]]}}</ref> The "dual input" warning will not activate at very low levels if the [[Ground proximity warning system|EGPWS]] activates due to its lower priority compared to EGPWS.<ref>[https://www.bea.aero/docspa/2006/ek-9060502/pdf/ek-9060502.pdf Final Report on the investigation into the accident involving the Armavia A320 near Sochi Airport on 3 May 2006], page 48, Published 12 February 2007</ref>
 === Active side-sticks ===
@@ Line 24: / Line 39: @@
 MC-21 ushers active sidesticks into commercial aircraft cockpits By Stephen Trimble 22 April 2015.</ref> This is the first [[airliner]] to use them.
-Such an active side-stick can also be used to increase adherence to a safe flight envelope by applying a [[Haptic technology|force feedback]] when the pilot makes a control input that would bring the aircraft closer to (or beyond) the borders of the safe flight envelope. This reduces the risk of pilots entering dangerous states of flights outside the operational borders while maintaining the pilots' final authority and increasing their [[situation awareness]].<ref>{{cite journal |author1=Florian J. J. Schmidt-Skipiol |author2=Peter Hecker |name-list-style=amp |title= Tactile Feedback and Situation Awareness-Improving Adherence to an Envelope in Sidestick-Controlled Fly-by-Wire Aircrafts.&#91;sic&#93; |url=https://www.researchgate.net/publication/299644586 |journal=15th AIAA Aviation Technology, Integration, and Operations Conference|page=2905|year=2015|doi=10.2514/6.2015-2905}}</ref>
+Such an active side-stick can also be used to increase adherence to a safe flight envelope by applying a [[Haptic technology|force feedback]] when the pilot makes a control input that would bring the aircraft closer to (or beyond) the borders of the safe flight envelope. This reduces the risk of pilots entering dangerous states of flights outside the operational borders while maintaining the pilots' final authority and increasing their [[situation awareness]].<ref>{{cite journal |author1=Florian J. J. Schmidt-Skipiol |author2=Peter Hecker |name-list-style=amp |title= Tactile Feedback and Situation Awareness-Improving Adherence to an Envelope in Sidestick-Controlled Fly-by-Wire Aircrafts.&#91;sic&#93; |url=https://www.researchgate.net/publication/299644586 |journal=15th AIAA Aviation Technology, Integration, and Operations Conference|page=2905|year=2015|doi=10.2514/6.2015-2905|isbn=978-1-62410-369-8 }}</ref>
 ==See also==

v t e Aircraft components and systems
Airframe structure	Aft pressure bulkhead Cabane strut Canopy Crack arrestor Cruciform tail Dope Empennage Fabric covering Fairing Flying wires Former Fuselage Hardpoint Interplane strut Jury strut Leading edge Lift strut Longeron Nacelle Rib Spar Stabilizer Stressed skin Strut T-tail Tailplane Trailing edge Triple tail Twin tail V-tail Vertical stabilizer Wing root Wing tip Wingbox
Flight controls	Aileron Airbrake Artificial feel Autopilot Canard Centre stick Deceleron Dive brake Dual control Electro-hydraulic actuator Elevator Elevon Flaperon Flight control modes Fly-by-wire Gust lock HOTAS Rudder Rudder pedals Servo tab Side-stick Spoiler Spoileron Stabilator Stick pusher Stick shaker Trim tab Wing warping Yaw damper Yoke
Aerodynamic and high-lift devices	Active Aeroelastic Wing Adaptive compliant wing Anti-shock body Blown flap Channel wing Dog-tooth Drag-reducing aerospike Flap Gouge flap Gurney flap Krueger flap Leading-edge cuff Leading-edge droop flap LEX Slats Slot Stall strips Strake Variable-sweep wing Vortex generator Vortilon Wing fence Winglet
Avionic and flight instrument systems	ACAS Air data boom Air data computer Aircraft periscope Airspeed indicator Altimeter Annunciator panel Astrodome Attitude indicator Compass Course deviation indicator EFIS EICAS Flight management system Glass cockpit GPS Head-up display Heading indicator Horizontal situation indicator INS ISIS Multi-function display Pitot–static system Radar altimeter TCAS Transponder Turn and slip indicator Variometer Yaw string
Propulsion controls, devices and fuel systems	Autothrottle Drop tank FADEC Fuel tank Gascolator Inlet cone Intake ramp NACA cowling NACA duct Self-sealing fuel tank Splitter plate Throttle Thrust lever Thrust reversal Townend ring War emergency power Wet wing
Landing and arresting gear	Aircraft tire Arrestor hook Autobrake Conventional landing gear Drogue parachute Landing gear Landing gear extender Oleo strut Tricycle landing gear Tundra tire
Escape systems	Ejection seat Escape crew capsule
Other systems	Aircraft lavatory Auxiliary power unit Bleed air system Deicing boot Emergency oxygen system Environmental control system Flight recorder Hydraulic system Ice protection system In-flight entertainment system Landing lights Navigation light Passenger service unit Ram air turbine