High Quality Content by WIKIPEDIA articles! A United States Army Air Forces (USAAF) bombardment group was a military combat unit during the Second World War. The Air Force equivalent of an infantry regiment, the bombardment or bomb group was the basic tactical control and administrative organization in all theaters of operation, and was commanded by a colonel or lieutenant colonel. U.S. bomb groups were numbered and classified into five types: Very Heavy (VH), Heavy (H), Medium (M), Light (L), and Composite, which combined bombers of differing categories.