In January 1960 , he became Deputy Secretary of Defense , filling the position left vacant since the sudden death of Donald A. Quarles in May 1959 .
Douglas served as Secretary of the Air Force until the end of 1959 .
In January 1960 , Douglas became Deputy Secretary of Defense , filling the position left vacant since the sudden death of Donald A. Quarles in May 1959 .
Douglas served as Secretary of the Air Force until the end of 1959 .