First Carrier Division
As the first of her kind, "Hōshō" provided valuable experience and insight into carrier air operations for the IJN. The ship was used for testing aircraft and equipment, particularly various types of arresting gear and optical landing aids. The lessons learned influenced the design and construction of and the subsequent conversions of battlecruiser and battleship into aircraft carriers. "Hōshō" was actively used to develop carrier operational methods and tactics for the IJN during the 1920s. She was assigned to the First Carrier Division with "Akagi" on 1 April 1928. During the 1930s "Hōshō" was fitted with three different types of transverse arresting gear for trials.