Side-stick

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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. Airbus A380 cockpit.jpg
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.
F-16 cockpit showing side-stick F-16D cockpit at EFKA.jpg
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 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]

Contents

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 ]

Handling of dual input situations

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 addition 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] .

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 aircraft with passive side-sticks, on the other hand, they and move independently from each other, and do not offer any haptic feedback on what the other pilot is inputting. This can lead to "dual input" situations, which should be avoided. To see how dual input situations are handled, see § Handling of dual input situations

Active side-sticks

However a later, significant, development is the 'active' side-stick, [15] 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 [16] to the pilot during manual flight. In fact the three largest avionics manufacturers, Honeywell, Rockwell Collins and Thales, [17] 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 [18] became the supplier of ‘active’ side-sticks for the Irkut MC-21. [19] 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. [20]

See also

Accidents

Related Research Articles

<span class="mw-page-title-main">Avionics</span> Electronic systems used on aircraft

Avionics are the electronic systems used on aircraft. Avionic systems include communications, navigation, the display and management of multiple systems, and the hundreds of systems that are fitted to aircraft to perform individual functions. These can be as simple as a searchlight for a police helicopter or as complicated as the tactical system for an airborne early warning platform.

<span class="mw-page-title-main">Fly-by-wire</span> Electronic flight control system

Fly-by-wire (FBW) is a system that replaces the conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals, and flight control computers determine how to move the actuators at each control surface to provide the ordered response. Implementations either use mechanical flight control backup systems or else are fully electronic.

<span class="mw-page-title-main">Joystick</span> Control lever used in aircraft and video games

A joystick, sometimes called a flight stick, is an input device consisting of a stick that pivots on a base and reports its angle or direction to the device it is controlling. Also known as the control column, it is the principal control device in the cockpit of many civilian and military aircraft, either as a centre stick or side-stick. It has various switches to control functions of the aircraft controlled by the Pilot and First Officer of the flight.

<span class="mw-page-title-main">Cockpit</span> Room from which a pilot controls an aircraft or spacecraft

A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle.

<span class="mw-page-title-main">Airbus A340</span> Wide-body, long-range, quad-engine jet airliner family

The Airbus A340 is a long-range, wide-body passenger airliner that was developed and produced by Airbus. In the mid-1970s, Airbus conceived several derivatives of the A300, its first airliner, and developed the A340 quadjet in parallel with the A330 twinjet. In June 1987, Airbus launched both designs with their first orders and the A340-300 took its maiden flight on 25 October 1991. It was certified along with the A340-200 on 22 December 1992 and both versions entered service in March 1993 with launch customers Lufthansa and Air France. The larger A340-500/600 were launched on 8 December 1997; the A340-600 flew for the first time on 23 April 2001 and entered service on 1 August 2002.

<span class="mw-page-title-main">Airbus A330</span> Wide-body twin-engine jet airliner

The Airbus A330 is a wide-body aircraft developed and produced by Airbus. Airbus began developing larger A300 derivatives in the mid-1970s, giving rise to the A330 twinjet as well as the Airbus A340 quadjet, and launched both designs along with their first orders in June 1987. The A330-300, the first variant, took its maiden flight in November 1992 and entered service with Air Inter in January 1994. The A330-200, a shortened longer-range variant, followed in 1998 with Canada 3000 as the launch operator.

<span class="mw-page-title-main">Glass cockpit</span> Aircraft instrumentation system consisting primarily of multi-function electronic displays

A glass cockpit is an aircraft cockpit that features an array of electronic (digital) flight instrument displays, typically large LCD screens, rather than traditional analog dials and gauges. While a traditional cockpit relies on numerous mechanical gauges to display information, a glass cockpit uses several multi-function displays and a primary flight display driven by flight management systems, that can be adjusted to show flight information as needed. This simplifies aircraft operation and navigation and allows pilots to focus only on the most pertinent information. They are also popular with airline companies as they usually eliminate the need for a flight engineer, saving costs. In recent years the technology has also become widely available in small aircraft.

<span class="mw-page-title-main">Aircraft flight control system</span> How aircraft are controlled

A conventional fixed-wing aircraft flight control system (AFCS) consists of flight control surfaces, the respective cockpit controls, connecting linkages, and the necessary operating mechanisms to control an aircraft's direction in flight. Aircraft engine controls are also considered flight controls as they change speed.

<span class="mw-page-title-main">Afriqiyah Airways</span> State-owned airline based in Tripoli, Libya

Afriqiyah Airways is a Libyan state-owned airline based in Tripoli, Libya. It was established in 2001 and operates both domestic and international flights. The airline's main hub is Tripoli International Airport (TIP), and it serves a wide range of destinations across Africa, the Middle East, and Europe.

<span class="mw-page-title-main">Yoke (aeronautics)</span> Aircraft controls

A yoke, alternatively known as a control wheel or a control column, is a device used for piloting some fixed-wing aircraft.

<span class="mw-page-title-main">Pilot error</span> Decision, action, or inaction by an aircraft pilot

In aviation, pilot error generally refers to an action or decision made by a pilot that is a substantial contributing factor leading to an aviation accident. It also includes a pilot's failure to make a correct decision or take proper action. Errors are intentional actions that fail to achieve their intended outcomes. The Chicago Convention defines the term "accident" as "an occurrence associated with the operation of an aircraft [...] in which [...] a person is fatally or seriously injured [...] except when the injuries are [...] inflicted by other persons." Hence the definition of "pilot error" does not include deliberate crashing.

<span class="mw-page-title-main">Armavia Flight 967</span> 2006 plane crash in the Black Sea off Sochi, Russia

Armavia Flight 967 was a scheduled international passenger flight operated by Armavia from Zvartnots International Airport, Zvarnots in Armenia to Sochi, a Black Sea coastal resort city in Russia. On 3 May 2006, the aircraft operating the route, an Airbus A320-200, crashed into the sea while attempting a go-around following its first approach to Sochi airport; all 113 aboard were killed. The accident was the first major commercial airline crash in 2006. It was Armavia's only fatal accident during the airline's existence.

<span class="mw-page-title-main">Bernard Ziegler</span> French engineer (1933–2021)

Bernard Ziegler was a French pilot and engineer, who served in Airbus as senior vice president for engineering, well known for his evangelical zeal for the application of the fly-by-wire system in the Airbuses. He was the son of Airbus founder Henri Ziegler.

<span class="mw-page-title-main">Centre stick</span>

A centre stick, or simply control stick, is an aircraft cockpit arrangement where the control column is located in the center of the cockpit either between the pilot's legs or between the pilots' positions. Since the throttle controls are typically located to the left of the pilot, the right hand is used for the stick, although left-hand or both-hands operation is possible if required.

<span class="mw-page-title-main">Qantas Flight 72</span> 2008 aviation accident over the Indian Ocean

Qantas Flight 72 (QF72) was a scheduled flight from Singapore Changi Airport to Perth Airport by an Airbus A330. On 7 October 2008, the flight made an emergency landing at Learmonth Airport near the town of Exmouth, Western Australia, following an inflight accident that included a pair of sudden, uncommanded pitch-down manoeuvres that caused severe injuries—including fractures, lacerations and spinal injuries—to several of the passengers and crew. At Learmonth, the plane was met by the Royal Flying Doctor Service of Australia and CareFlight. Fourteen people were airlifted to Perth for hospitalisation, with thirty-nine others also attending hospital. In all, one crew member and eleven passengers suffered serious injuries, while eight crew and ninety-nine passengers suffered minor injuries. The Australian Transport Safety Bureau (ATSB) investigation found a fault with one of the aircraft's three air data inertial reference units (ADIRUs) and a previously unknown software design limitation of the Airbus A330's fly-by-wire flight control primary computer (FCPC).

<span class="mw-page-title-main">Flight envelope protection</span>

Flight envelope protection is a human machine interface extension of an aircraft's control system that prevents the pilot of an aircraft from making control commands that would force the aircraft to exceed its structural and aerodynamic operating limits. It is used in some form in all modern commercial fly-by-wire aircraft. The professed advantage of flight envelope protection systems is that they restrict a pilot's excessive control inputs, whether in surprise reaction to emergencies or otherwise, from translating into excessive flight control surface movements. Notionally, this allows pilots to react quickly to an emergency while blunting the effect of an excessive control input resulting from "startle," by electronically limiting excessive control surface movements that could over-stress the airframe and endanger the safety of the aircraft.

<span class="mw-page-title-main">Air France Flight 447</span> 2009 mid-Atlantic ocean aircraft accident

Air France Flight 447 (AF447/AFR447) was a scheduled international passenger flight from Rio de Janeiro, Brazil, to Paris, France. On 1 June 2009, inconsistent airspeed indications and miscommunication led to the pilots inadvertently stalling the Airbus A330. They failed to recover the plane from the stall, and the plane crashed into the mid-Atlantic Ocean at 02:14 UTC, killing all 228 passengers and crew on board.

<span class="mw-page-title-main">Flight control modes</span> Aircraft control computer software

A flight control mode or flight control law is a computer software algorithm that transforms the movement of the yoke or joystick, made by an aircraft pilot, into movements of the aircraft control surfaces. The control surface movements depend on which of several modes the flight computer is in. In aircraft in which the flight control system is fly-by-wire, the movements the pilot makes to the yoke or joystick in the cockpit, to control the flight, are converted to electronic signals, which are transmitted to the flight control computers that determine how to move each control surface to provide the aircraft movement the pilot ordered.

<span class="mw-page-title-main">Afriqiyah Airways Flight 771</span> 2010 passenger plane crash in Tripoli, Libya

Afriqiyah Airways Flight 771 was a scheduled international Afriqiyah Airways passenger flight from Johannesburg, South Africa to Tripoli, Libya. On 12 May 2010 at about 06:01 local time while on approach to Tripoli International Airport, the aircraft crashed about 1,200 metres short of the runway. Of the 104 passengers and crew on board, 103 were killed. The sole survivor was a 9-year-old Dutch boy.

References

  1. Crane, Dale: Dictionary of Aeronautical Terms, third edition, page 463. Aviation Supplies & Academics, 1997. ISBN   1-56027-287-2
  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.
  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. "Commercial Active Sticks - An Active Role". BAE Systems | International. Retrieved 2019-08-10.
  16. "BAE Brochure" (PDF).
  17. Dubois, Thierry (29 June 2015). "Cockpits of the Future". Skies magazine. Archived from the original on 6 February 2021. Retrieved 6 February 2021.
  18. https://www.youtube.com/watch?v=3sXXx8rgeeE, How Collins Active Control Sidesticks Work – Aviation International News Aug 13, 2019
  19. 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.
  20. 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.