Joseph Carroll (DIA)
When the U.S. Air Force was established as a separate executive department under the National Security Act of 1947, Secretary of the Air Force W. Stuart Symington, requested FBI Director J. Edgar Hoover to loan General Carroll to the services to organize a U.S. Air Force agency for investigative and counterintelligence functions. He organized and directed this new organization, the AFOSI, along the lines of the FBI rather than the U.S. Army's Criminal Investigation Command (USACIDC or CID). General Carroll was tendered a commission as a colonel, U.S. Air Force Reserve, January 12, 1948. He was ordered to active duty in the grade of brigadier general May 6, 1948, and promoted to major general August 11, 1950.
United States Air Force
The act created the "National Military Establishment" (renamed Department of Defense in 1949), which was composed of three subordinate Military Departments, namely the Department of the Army, the Department of the Navy, and the newly created Department of the Air Force. Prior to 1947, the responsibility for military aviation was shared between the Army Air Forces and its predecessor organizations (for land-based operations), the Navy (for sea-based operations from aircraft carriers and amphibious aircraft), and the Marine Corps (for close air support of Marine Corps operations). The 1940s proved to be important for military aviation in other ways as well. In 1947, Air Force Captain Chuck Yeager broke the sound barrier in his X-1 rocket-powered aircraft, beginning a new era of aeronautics in America.