 "Hiryū"s primary anti-aircraft (AA) armament consisted of six twin-gun mounts equipped with 40-caliber 12.7-centimeter Type 89 dual-purpose guns mounted on projecting sponsons, three on either side of the carrier's hull.When firing at surface targets, the guns had a range of ; they had a maximum ceiling of at their maximum elevation of +90 degrees.Their maximum rate of fire was 14 rounds a minute, but their sustained rate of fire was approximately eight rounds per minute.