Carrier battle group at the Battle of Midway. In contrast, the United States Navy deployed its large carriers in separate formations, with each carrier assigned its own cruiser and destroyer escorts. These single-carrier formations would often be paired or grouped together for certain assignments, most notably the Battle of the Coral Sea and Midway. By 1943, however, large numbers of fleet and light carriers became available, which required larger formations of three or four carriers. These groups eventually formed the Fast Carrier Task Force, which became the primary battle unit of the U.S. Fifth and Third Fleets. With the construction of the large
Japanese aircraft carrier Shōkaku was added at the bow and stern and 10 single mounts were added before the Battle of the Philippine Sea in June 1944. "Shōkaku" and "Zuikaku" formed the Japanese 5th Carrier Division, embarking their aircraft shortly before the Pearl Harbor attack. Each carrier's aircraft complement consisted of 15 Mitsubishi A6M2 "Zero" fighters, 27 Aichi D3A1 "Val" dive bombers, and 27 Nakajima B5N1 or −2 "Kate" torpedo bombers. "Shōkaku" and "Zuikaku" joined the "Kido Butai" ("Mobile Unit/Force", the Combined Fleet's main carrier battle group) and participated in Japan's early wartime naval offensives, including Pearl Harbor and the attack on Rabaul in