U.S. Air Force Senior Airman Douglas Prewitt, with the 621st Contingency Response Wing, marshals a C-17 Globemaster III aircraft at Geronimo Landing Zone during the Joint Readiness Training Center 14-03 field training exercise at Fort Polk, La., Jan. 16, 2014. The exercise provides military units and personnel with realistic pre-deployment training scenarios in all aspects of armed conflict.