What causes the nose landing gear knocking noise on a Boeing 777 while taxiing? The NLG knocking noise heard on taxi-in to stand, what could cause this knocking noise?
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That's a pilot taxiing perfectly on the centerline, which makes one of the two nose landing gear tires hit all the taxiway centerline lights.

Just like the sound the tires of a car make when they hit the cat's eyes on a road at speed.