U.S. Air Force Staff Sgt. Justin Hubbard, 94th Fighter Squadron dedicated crew chief, slides protective booties over his boots during an intake and exhaust inspection on a F-22 Raptor at Langley Air Force Base, Va., June 4, 2014. Crew chiefs perform preventive maintenance, pre- and post-flight inspections and maintain and repair the aircraft, inside and out. (U.S. Air Force photo by Staff Sgt. Antoinette Gibson/Released)