Airmen assigned to the 18th Aeromedical Evacuation Squadron from Kadena Air Base, Japan, prepare to load simulated casualty victims during readiness exercise Vigilant Ace 16 at Osan Air Base, Republic of Korea, Nov. 5, 2015. The 18 AES is participating in Vigilant Ace 16, a large-scale exercise designed to enhance combat capabilities and interoperability of the U.S. and Republic of Korea Air Forces. (U.S. Air Force photo/Staff Sgt. Benjamin Sutton)