I recently flew with an A321 and watched the left wing while the pilot tested the control surfaces before lift off. I noticed that one of the spoilers angled upwards much less than all others. In the drawing below, it was spoiler number 3 (labelled as an "air brake" [sic]). The pilot extended them twice, and the behaviour was the same each time.

schematic drawing of left wing of an A318/A319/A320 showing the naming of different control surfaces

  • $\begingroup$ Questions are closed as duplicate when it's the same question: "do" is very different from "why", and the answers are very different. I voted to reopen. $\endgroup$
    – user14897
    Apr 7, 2022 at 10:04
  • 1
    $\begingroup$ The answer for "do they do X" is certainly provided when the answer to "why do they do X" confirms that X happens as introduction to explaining why. I see no value in reopening, particularly since the OP found the duplicate thread to be useful. $\endgroup$
    – Ralph J
    Apr 7, 2022 at 13:24
  • $\begingroup$ @RalphJ: To avoid a discussion here, now on meta: Why is this A321 spoilers question closed as a duplicate? $\endgroup$
    – user14897
    Apr 7, 2022 at 15:05

1 Answer 1


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A321's flight controls check via YouTube

They indeed do on the A321. To be precise, what you saw happens during the roll function (banking left/right), not the slowing down and spoiling lift functions. Here's an extract from the A321's flight manual:



The maximum deflection of the spoilers is:

  • 35 ° for spoilers 2, 4, and 5
  • 7 ° for spoilers 3.

And compare with the A320:



The maximum deflection of the spoilers is 35 °.

For the difference: Why is there a difference in the max spoilers extension between the A320 and A321 in a roll?

Note: both do not use spoiler 1 for rolling.

Further reading:


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