Originally designated as 43d Air Division (Defense) when organized on 1 March 1952, the division was redesignated 43d Air Division on 18 March 1955. The unit was discontinued and inactivated, on 1 October 1957. The 43d Air Division assumed responsibility for the air defense of Southwestern Japan (Kyūshū, in March 1952. The 43d also included the western part of Honshū, and most of Shikoku), using radar, fighter aircraft, and ground weapons to prevent or disrupt enemy air attacks. It supported numerous exercises, some involving U.S. and British naval vessels, and training for the Japan Air Self Defense Force. The division also supervised electronic countermeasures (ECM), and weather reconnaissance missions. In the summer of 1957, when the Nagasaki area suffered severe flooding, the 43d assis