Radford took command of the Aviation Training Division in Washington, D.C. on 1 December 1941, seven days before the attack on Pearl Harbor that brought the United States into World War II. He was appointed as Director of Aviation Training for both the Office of the Chief of Naval Operations and the Bureau of Navigation; the double appointment helped to centralize training coordination for all naval aviators. With the U.S. mobilizing for war, Radford's office worked long hours six days a week in an effort to build up the necessary training infrastructure as quickly as possible. For several months, this around-the-clock work took up all of his time, and he later noted that walking to work was his only form of exercise for several months. During this time, he impressed colleagues with a direct and no-nonsense approach to work, while maintaining a demeanor that made him easy to work for. He was promoted to captain soon after.