GRADUATION SALUTE Air Force Secretary Michael B. Donley enters the U.S. Air Force Academy's Falcon Stadium for the Class of 2013's commencement ceremony in Colorado Springs, Colo., May 29, 2013. More than 1,000 cadets received their diplomas and commissions at the ceremony. SHARE: Download: Full Size (0.08 MB) Credit: VIRIN: 013370-N-LLM18-102.jpg Photo Gallery