Re:Serious incident to the 777-300ER on 5 April 2022 at CDG ...
by spangry on Thursday January 18, 2024 @11:12AM
(#39043512)
What a horribly confusing control mechanism. It could become very hard to distinguish between (1) desynchronization (2) your copilot yielding control to you and (3) a control jam being overcome. They would all feel exactly the same. Not the sort of ambiguity you would want in an emergency situation!
Re:Serious incident to the 777-300ER on 5 April 2022 at CDG ...
by gambiting on Thursday January 18, 2024 @11:26AM
(#39043716)
I'd like to think that people designing this aren't idiots - they are very well trained intelligent engineers. And probably the reason why this method was chosen was because it has some objective advantages over any other method. I don't know what those advantages might be, but I really hope they exist.
Re:Serious incident to the 777-300ER on 5 April 2022 at CDG ...
by cesarb on Thursday January 18, 2024 @12:41PM
(#39044808)
> I don't know what those advantages might be, but I really hope they exist.
The advantage is obvious: it's the most similar to how it worked back when the controls were fully mechanical.
IIRC, some old planes even had each side mechanically controlling independent halves of the control surfaces, such that the end result is the average of the inputs in case one of the control surfaces (or the cabling connecting to the controls) is jammed.
> in the event of antagonistic inputs exceeding the breakout mechanism’s activation threshold, the controls would be desynchronised and the control surface would react according to the mean control position.
The breakout threshold is 50lbs, but it’s the combined thresholds, so sudden opposite force applied by two pilots (as apparently happened here) can unexpectedly trigger it. The report confirms there is no warning of breakout situation whether visual or aural.