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Shouldn't there be an override switch to tell the plane to only accept one of the two control inputs, for situations like this where one of the inputs suffers s

Shouldn't there be an override switch to tell the plane to only accept one of the two control inputs, for situations like this where one of the inputs suffers some physical damage or jam? None of the hundreds of cockpit switches does that? What happens if one pilot dumps their entire cup of coffee onto their controls and it malfunctions causing erroneous input? Is it basically game over?

hlandau 10y ago
There is. Google "sidestick priority".
- cypherpunks01 10y ago
  Thanks! That is reassuring to know. Shouldn't they have used it in this case when they knew an input was jammed? Obviously it worked out when the computer decided to ignore them, but just curious what the correct procedure should have been here.
  - hlandau 10y ago
    I should note that I'm not an expert on this subject. According to the below, Airbus cockpit sidesticks have a red button on them. Pressing it disengages the autopilot if it's engaged, which is probably the more normal use. Pressing it when the autopilot is already disengaged engages sidestick priority for as long as it's held down. It latches if held continuously for 40 seconds. http://aviation.stackexchange.com/questions/3455/why-is-the-priority-takeover-button-used http://aviation.stackexchange.com/questions/3455/why-is-the-... If they were on the ceiling perhaps it could be difficult to hold the button down continuously for 40 seconds.
  - rtkwe 10y ago
    > “With his feet on the flight deck roof, the co-pilot reached down and attempted to disengage the autopilot by pulling back on his sidestick,” In this case I don't think they really knew that the issue was the jammed stick before the co-pilot pulling back on his stick gave the flight computer priority. It's hard to really say from the information given exactly when they discovered the camera was jammed and removed it vs when the plane was getting itself back under control.
    - rconti 10y ago
      They also said the captain was pulling back on the stick as well.. or at least ATTEMPTING to. Maybe they're indicating that the stuck camera (which seems to have come unstuck before recovery was complete?) prevented him from doing so. It would be really weird for both pilots pulling back on the stick to result in a dual input error situation.
      - rtkwe 10y ago
        Not that weird I think the net force on the Captain's stick was probably still forward with the camera jammed there with him trying to pull back.
thisrod 10y ago
Does anyone know how often airliner flight controls get drenched in coffee, and how well they resist it? You never hear about it happening, and there are enough planes in the sky that things often go wrong in much less obvious ways.
DonaldFisk 10y ago
On most planes, from Boeings to Cessnas but not Airbuses, the two sets of controls are linked, so that if you move the yoke (pitch/roll) or rudder pedals (yaw) in one set they move in the other set. This means that one pilot knows what the other is doing. Airbuses average the two inputs by default, though either pilot can take control. SPOILER ALERT: A coffee spill was the cause of the plane crash in the movie Fate is the Hunter (1964), so I assume the risk is well-known.

hlandau 10y ago

There is. Google "sidestick priority".

cypherpunks01 10y ago
Thanks! That is reassuring to know. Shouldn't they have used it in this case when they knew an input was jammed? Obviously it worked out when the computer decided to ignore them, but just curious what the correct procedure should have been here.
- hlandau 10y ago
  I should note that I'm not an expert on this subject. According to the below, Airbus cockpit sidesticks have a red button on them. Pressing it disengages the autopilot if it's engaged, which is probably the more normal use. Pressing it when the autopilot is already disengaged engages sidestick priority for as long as it's held down. It latches if held continuously for 40 seconds. http://aviation.stackexchange.com/questions/3455/why-is-the-priority-takeover-button-used http://aviation.stackexchange.com/questions/3455/why-is-the-... If they were on the ceiling perhaps it could be difficult to hold the button down continuously for 40 seconds.
- rtkwe 10y ago
  > “With his feet on the flight deck roof, the co-pilot reached down and attempted to disengage the autopilot by pulling back on his sidestick,” In this case I don't think they really knew that the issue was the jammed stick before the co-pilot pulling back on his stick gave the flight computer priority. It's hard to really say from the information given exactly when they discovered the camera was jammed and removed it vs when the plane was getting itself back under control.
  - rconti 10y ago
    They also said the captain was pulling back on the stick as well.. or at least ATTEMPTING to. Maybe they're indicating that the stuck camera (which seems to have come unstuck before recovery was complete?) prevented him from doing so. It would be really weird for both pilots pulling back on the stick to result in a dual input error situation.
    - rtkwe 10y ago
      Not that weird I think the net force on the Captain's stick was probably still forward with the camera jammed there with him trying to pull back.

thisrod 10y ago

Does anyone know how often airliner flight controls get drenched in coffee, and how well they resist it? You never hear about it happening, and there are enough planes in the sky that things often go wrong in much less obvious ways.

DonaldFisk 10y ago

On most planes, from Boeings to Cessnas but not Airbuses, the two sets of controls are linked, so that if you move the yoke (pitch/roll) or rudder pedals (yaw) in one set they move in the other set. This means that one pilot knows what the other is doing. Airbuses average the two inputs by default, though either pilot can take control. SPOILER ALERT: A coffee spill was the cause of the plane crash in the movie Fate is the Hunter (1964), so I assume the risk is well-known.