U.S. Air Force crew chiefs assigned to the 35th Aircraft Maintenance Squadron listen to in-processing briefings prior to VIGILANT ACE 18 at Osan Air Base, Republic of Korea, Nov. 30, 2017. Once Airmen disembark transport aircraft, local 51st Fighter Wing briefings impart better understanding of procedures, exercise rules of engagement and supporting agencies available for use. More than 280 personnel relocated to Osan AB for the annually held exercise, further enhancing the region’s joint and bilateral readiness among sister services and Indo-Asia- Pacific allies. (U.S. Air Force photo by Staff Sgt. Deana Heitzman)