While observing taxiing A321 planes, I noticed that they had an open hatch-like opening on the bottom right of door 4R. I marked it here on a picture I found online.

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I could not locate it in the Airbus A321 Aircraft Characteristics manual. What is it for? Why was it open? Does it stay open during flight?


marked as duplicate by ymb1, Ron Beyer, Ralph J, Manu H, Community Sep 1 at 20:04

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