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