During World War II, he first tried to join the US Navy but was rejected because of poor eyesight, so he joined the US Army Air Forces as an Intelligence officer. After receiving his commission as a first lieutenant in 1942, he completed training at bases near Miami, Florida and Harrisburg, Pennsylvania. He was assigned to the 319th Bombardment Group, which moved to England later that year. He served in North Africa during Operation Torch and was later assigned to the Headquarters of the Northwest African Air Forces. There, Powell served in Sicily during the Allied invasion of Sicily.