The standard responses to “ahoy”, when used in nautical terms, vary depending on who’s on the boat being hailed.  If you have a commissioned officer aboard, “aye aye” is the correct response.  If no officer is aboard, “no no” is the correct response.  If a captain of a different ship is on board, the name of the ship is the proper response.  Finally, if an admiral is aboard the vessel, the proper response is “flag”.

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