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
Imperial Japanese Navy in World War II the Mobile Fleet, along with large numbers of land-based aircraft, would be concentrated. If the Americans attacked the Marianas, they would be attacked upon by land-based planes in that vicinity. Then the Americans would be lured into the areas where the Mobile Fleet could defeat them. A month after Koga's death, Admiral Soemu Toyoda become the new commander of Combined Fleet. This opportunity for a decisive battle came in June 1944 when the Americans landed on Saipan in the Marianas. The Japanese responded with their largest carrier force of the war, with the nine carrier Mobile Fleet, led by the