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Airbus A380's empennage

Source: Wikipedia

I want to know if any moment that the left and right elevator are activated (used/functioned) differently of a civil or passenger airplane. Here I am talking about civil airplane, not a fighter jet. I.e., one (side) elevator is pulled up/down while another elevator of another side remain "neutral" or neither pulled up nor pulled down. If any, when or in what condition?

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No, there is no situation where left and right elevators are intentionally deflected differently in any civil aircraft. (I assume that the "ruddervators" of V-tailed airplanes don't count!)

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  • $\begingroup$ Do any commercial planes have single sided trim tabs? Certainly some GA planes do. $\endgroup$ Commented Oct 13, 2022 at 4:57
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    $\begingroup$ @tedder42 Transport category aeroplanes typically use a THS (trimmable horizontal stabilizer), not trim tabs. $\endgroup$
    – Bianfable
    Commented Oct 13, 2022 at 6:31
  • $\begingroup$ Yes, I am talking common airplane that their tail is like in the picture which they has vertical and horizontal stabilizer. V-tail or inverted V-tail, or other similar is not included. $\endgroup$ Commented Oct 13, 2022 at 10:35
  • $\begingroup$ @tedder42, I don't really understand you you mentioned. As my question, if any moment that left and right elevator activated differently, when or in what condition? $\endgroup$ Commented Oct 13, 2022 at 10:37
  • $\begingroup$ @aircraftlover I don't know what categories either be included under "common airplane" but thanks bianfable, didn't know for sure if large commercial/transport had anything single sided. $\endgroup$ Commented Oct 14, 2022 at 11:39
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Just to add something to @quietflyer answer.

This is the schematics of the B747's hydraulic system:

Boeing 747 hydraulic system schematic

For safety reasons it is quadruple-redundant, with each moving surface split into two parts each driven by one or two different systems. As visible, the following connection exist for the elevators:

  • left outboard elevator $\rightarrow$ 1
  • left inboard elevator $\rightarrow$ 1+2
  • right inboard elevator $\rightarrow$ 3+4
  • right outboard elevator $\rightarrow$ 4

So, in case of failure of systems 1 and 2 (or 3 and 4) an asymmetrical movement of the elevators could actually happen.

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  • $\begingroup$ That is true in case of failure. But failure means, no more option rather than have to do the available option. What I am asking is in an operation which no failure. $\endgroup$ Commented Oct 16, 2022 at 13:17
  • $\begingroup$ @AirCraftLover: "What I am asking is in an operation which no failure". Sorry it was not clear from you question. $\endgroup$
    – sophit
    Commented Oct 16, 2022 at 13:48

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