521st Air Defense Group (original) (raw)

The 521st Air Defense Group is a disbanded United States Air Force organization. Its last assignment was with the 31st Air Division at Sioux City Municipal Airport, Iowa, where it was inactivated in 1955. The group was originally activated as a support unit for the 310th Bombardment Group at the end of World War II in Italy and then redeployed to the United States where it was inactivated in 1945.