I'm not sure but I wouldn't be surprised if the carrier you sunk or one of it's sisters is spawning all these planes. Sometimes they keep spawning long after the carrier has departed.
I wish there was a better way of representing aircraft in the game than 'spawning'. However tracking each individual patrol plane and air squadron on their daily flights and routines would probably slow the game to a crawl.
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--Mobilis in Mobili--
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