The 500th Air Expeditionary Group is a provisional United States Air Force unit. Its last known assignment was at Christchurch, New Zealand, where it was activated for the summer 2005–2006 season. The unit's origins lie with its predecessor unit, the United States Army Air Forces 500th Bombardment Group, which was part of Twentieth Air Force during World War II. The 500th engaged in very heavy (Boeing B-29 Superfortress) bombardment operations against Japan. It was awarded two Distinguished Unit Citations for actions in 1945. The 500th Air Refueling Wing replaced the 4045th Air Refueling Wing as a Strategic Air Command tanker unit at Selfridge Air Force Base, Michigan on 1 January 1963. The two units were consolidated in 1984. In 2002, the consolidated unit was converted to provisional status as the 500th Air Expeditionary Group. It has been activated several times to support operations in Antarctica. History World War II The group was established as the 500th Bombardment Group in late 1943 at Gowen Field, Idaho. It was formed as a Boeing B-29 Superfortress very heavy bombardment group. The unit was initially composed of four bombardment squadrons, the 881st, 882d, 883d, and 884th Bombardment Squadrons, the 29th, 30th, 31st and 32d Bombardment Maintenance Squadrons and the 18th Photographic Laboratory (Bombardment, Very Heavy). Due to a shortage of B-29s, the group was equipped with Boeing B-17 Flying Fortresses already at Gowen Field. These aircraft were previously used for training heavy bomber replacement personnel. In January the unit moved to Clovis Army Air Field, New Mexico due to the poor flying weather during the winter in Idaho. It moved to Walker Army Air Field, Kansas in April 1944 where it finally received newly manufactured B-29 Superfortresses from the Boeing plant at Wichita, Kansas. In May the United States Army Air Forces reconfigured its very heavy groups and the 884th Bombardment Squadron and the Bombardment Maintenance Squadrons were inactivated. Their personnel were consolidated into the remaining squadrons. The 500th deployed to the Pacific Theater of Operations in September 1944, where it was assigned to the 73d Bombardment Wing of XXI Bomber Command in the Northern Mariana Islands, at Isely Field, Saipan. Upon their arrival the group's personnel engaged in Quonset hut construction. By mid-October most personnel were able to move into the huts from the tents which they were assigned to on their arrival in theater. The 500th's assigned tail code was a Z-Square.