The War Department assumed control of the airport in February 1942, just weeks after Japan's attack on Pearl Harbor, which led the United States to enter World War II. The airport was renamed the Visalia Army Air Field (Visalia AAF) and operations at the facility began almost immediately upon the United States Army Air Forces control of the airfield. Anti-submarine patrols were conducted from Visalia AAF by the 47th Bombardment Squadron (Medium) using Lockheed A-29 Hudson, and later B-25 Mitchell medium bombers.