Perimeter Security Airmen secure a perimeter during a simulated attack while participating in an operational readiness exercise at Offutt Air Force Base, Neb., Jan. 23, 2018. The exercise tested the 55th Wing’s readiness and ability to meet wartime and contingency tasks. Air Force photo by Tech. Sgt. Rachelle Blake SHARE: Download: Full Size (1.28 MB) Tags: Air Force, Northcom, Northern Command, training, Airmen Credit: Tech. Sgt. Rachelle Blake VIRIN: 180123-F-HK400-025A.JPG Photo Gallery