The Akizuki-class destroyers were one of the primary classes of new destroyers of the Imperial Japanese Navy (IJN) after 1942. The IJN called them Type-B Destroyer from their plan name. They were designed to fight smaller ships, aircraft and submarines.
This is considered to have been the most useful class of destroyers Japan fielded during the war and was well regarded in the IJN. They mounted 3.9-inch (100mm) Type 98 dual-purpose guns in four twin mounts. They also were among the first Japanese vessels equipped with radar. The ships were lighter in their torpedo armament than most contemporary Japanese destroyers, which typically had a heavy emphasis on offensive torpedo armament, most classes having two 4-tube centerline launchers capable of firing to either side, with quick-reloads for both launchers. The Akizuki class had only a single four tube launcher, plus reloads, but the ships compensated with stronger anti-aircraft armament, having four turrets as opposed to three, with guns firing shells of smaller caliber but greater velocity, and therefore effectiveness. The first 7 ships were built under the Maru 4 Programme and the latter on Maru Kyū Programme.
The Fuyutsuki subclass (Harutsuki, Yoizuki) were originally going to be built to the same specifications as the Akizuki class but construction was more simplified. Four vessels were built under the Maru Kyū Programme. The main differences from the Akizuki class were simplified bow design, removed rear deck house, and fitted two-dimensional air inlet for boilers. However, the IJN was not satisfied with the design. More modifications were ordered, leading to the Michitsuki subclass.