313th Air Division The 313th Air Division ( 313th AD ) is an inactive United States Air Force unit . Its last assignment was with Pacific Air Forces , based at Kadena AB , Okinawa . It was inactivated on 1 October 1991 . History . The unit ' s origins begin with its predecessor , the World War II 313th Bombardment Wing ( 313th BW ) was part of Twentieth Air Force . The 313th BW engaged in very heavy bombardment B - 29 Superfortress operations against Japan . World War II . The 313th Bombardment Wing was organized at Peterson Field , Colorado in the spring of 1944 as a Very Heavy ( VH ) bombardment wing , to be equipped with the Boeing B - 29 Superfortress es . Operational groups assigned to the wing were the 6th and 9th Bombardment Groups , both were existing units with the 6th being reassigned from the Sixth Air Force in the Caribbean , where it was performing antisubmarine missions and protecting the Panama Canal from airfields in Panama . The 9th was assigned to Army Air Force Training Command in South Florida as part of its school of applied tactics . Both groups were reassigned to bases in Nebraska – to ( Grand Island AAF and McCook AAF ) respectfully where they trained initially on B - 17 Flying Fortress es until their B - 29 aircraft could be manufactured and made available to them . Two other groups , the 504th and 505th were formed as new units ( 504th at Fairmont AAF , the 505th at Harvard AAF ) , also being assigned to bases in Nebraska for training . After dealing with various training issues and also problems with the B - 29s they received , the combat groups were ready to deploy to the Pacific Theater and departed for North Field , Tinian , in the Northern Mariana Islands arriving during late December 1944 . On Tinian , the wing was assigned to the XXIst Bomber Command of Twentieth Air Force . Once in place , the groups of the 313th began flying missions , initially against Iwo Jima , the Truk Islands , and other Japanese held areas . Later , they flew low - level night incendiary raids on area targets in Japan ; participated in mining operations in the Shimonoseki Strait , and contributed to the blockade of the Japanese Empire by mining harbors in Japan and Korea . In April 1945 the 313th assisted the invasion of Okinawa by bombing Japanese airfields used by kamikaze pilots . A fifth group , the 509th Composite Group , was assigned to the wing in May 1945 from Wendover AAF , Utah . The 509th , although assigned to the 313th Bomb Wing , was operationally controlled by Headquarters , Twentieth Air Force . The 509th was given a base area near the airfield on the north tip of Tinian , several miles from the main installations in the center part of the island where the other groups were assigned . Also unlike the other groups in the wing , the 509th used a wide variety of tail codes from various XXI Air Force groups , instead of using its own , so that the group ' s planes could not be identified by the Japanese . The 509th was also self contained , and drew little in resources from the 313th Wing or its other groups . In early August , the mission of the 509th was revealed when the group flew the Atomic Bomb missions to Hiroshima and Nagasaki . In November , the 509th was relieved from assignment to the 313th Bomb Wing and was reassigned to Roswell AAF , New Mexico . After the Japanese surrender in August , 313th Bomb Wing units dropped food and supplies to Allied prisoners and participated in show - of - force flights over Japan . As part of the postwar drawdown of forces , two of the Wing ' s groups , the 504h and 505th were inactivated in late 1945 and early 1946 . Another group , the 383d , was reassigned to the 313th Bomb Wing from Eighth Air Force in September 1945 after the Eighth was drawn down on Okinawa . The Eighth Air Force was planned to be a second strategic Air Force to be used during the Invasion of Japan which never materialized . The 383d was inactivated in December with its aircraft and personnel returning to the United States . Pacific Air Forces . In March 1946 , the 313th was reassigned to Thirteenth Air Force in the Philippine Islands . In the Philippines , the wing was assigned the 5th Bomb Group from Seventh Air Force where it conducted Bombardment training , aerial reconnaissance and mapping and construction projects . The 5th Reconnaissance Group conducted many clandestine mapping missions over non - friendly areas of Asia during the postwar era . The wing itself began phasing down for inactivation in late 1947 , with the 6th and 9th bomb groups being inactivated in June 1947 , and finally the 5th bomb group in January 1948 . The 313th Bombardment Wing was itself inactivated in June 1948 . In March 1955 , the organization was redesignated as the United States Air Force 313th Air Division ( 313th AD ) as part of Far East Air Forces Fifth Air Force , being assigned to Kadena Air Base , Okinawa . The mission of the 313th AD was the command and control of USAF units assigned to Okinawa . Throughout the years of the Cold War , the 313th AD assumed responsibility for air defense of the Ryukyu Islands and tactical operations in the Far East , maintaining assigned forces at the highest possible degree of combat readiness . In addition , it supported Fifth Air Force in the development , planning , and coordination of requirements for future Air Force operations in the Ryukyu Islands . The division also supported numerous PACAF exercises such as Cope Thunder , Cope Diamond , Team Spirit , and Cope North . The 313th was inactivated on 1 October 1991 as part of a general drawdown of USAF forces in the Pacific after the end of the Cold War . Units assigned . United States Air Force . Wings Group Squadrons