NUTS AND BOLTS U.S. Air Force Staff Sgt. Christopher Matthews inspects an F-16 Fighting Falcon exhaust nozzle on Spangdahlem Air Base, Germany, March 16, 2010. Matthews, an aerospace propulsion systems craftsman, is assigned to the 52nd Component Maintenance Squadron. SHARE: Download: Full Size (0.09 MB) Credit: VIRIN: 688250-M-WJR73-062.jpg Photo Gallery