You can earn this at any time in the first Japanese campaign mission, but it is easiest in phase one when you control a Zero. You need to destroy the 9 objective planes and all the other parked aircraft on the map. There is one seaplane just off the shore under your flight path as you are approaching the harbor, and all the rest are on the airbase island or in the waters directly next to it. This achievement unlocks as soon as the last plane is destroyed. Take your time and make sure you have them all before destroying the last objective plane. If it doesn’t unlock there, search around in phase two and find any missing planes before you bomb the battleship.