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There have been accidents where one pilot gets confused, panics, inappropriately pulls or pushes the control column, and the other pilot does not manage to get control from them and the aircraft either stalls or nosedives into the ground. Recent example is Atlas flight 3591, but there have been other airliner accidents, and Dan Gryder mentions it as probable cause of some training flight accidents.

Now in aircraft with mechanical controls, when opposing forces are applied to the control columns (including on the Atlas B767), they usually split and each half controls the respective aileron and half of elevator, which is rarely enough to recover. On the other hand on fly-by-wire Airbus, the non-confused pilot can simply press the control priority button and recover (the confused pilot is unlikely to press the button the necessary way to win a priority contest).

But a B777 has connected fly-by-wire control columns. Is there an emergency option to disconnect them and specify which one the aircraft should respond to?

Jan Hudec
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    Related: How does the Boeing 777's yoke of both the captain and the first officer have synchronized movement? – Bianfable Jul 08 '21 at 17:01
  • @Bianfable, that explains a lot of it, though a bit more detail on how it picks which side to then listen to would be welcome. – Jan Hudec Jul 08 '21 at 17:24
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    I just checked the FCOM and FCTM again. There is an entire chapter about "Jammed Flight Controls" in the FCTM, which describes the proper way to override the jammed controls. But it always assumes a jam, it does not cover the case of opposite inputs, which is what you are asking about. I can tell you that there is no control priority button to disable one yoke, but I am not sure what would happen in case of opposite inputs. Maybe Mike Sowsun (B777 pilot) will know... – Bianfable Jul 08 '21 at 17:44
  • I guess that would be an answer. As long as the confused pilot is pushing or pulling with all their might, it is indistinguishable from any other jam, and we probably won't know what happens when the jam is “cleared” (the plane breaks out of clouds and the confused pilot realizes they are pushing the wrong way) until somebody makes an AQP scenario out of the Atlas 3591 or similar accident. – Jan Hudec Jul 08 '21 at 18:29

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No it doesn't have one - there is no need really. On the Airbus, the control movements on one side stick are not replicated on the other - therefore it's very difficult for one pilot to really be sure what the other is inputting to the controls. On Boeings, the control inputs are replicated - therefore, by using physical force, one pilot can overpower the other's inputs. It the 'bad' pilot is stronger (and 'fights' the other's inputs) he may still be able to put in the incorrect controls.

Glorfindel
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Siriusfire
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