ELLSWORTH AIR FORCE BASE S.D. -- Senior Airman Kristi Terwilliger, 28th Security Forces Squadron controller, patrols the simulated perimiter during a phase II operational readiness exercise, July 20. The phase II ORE is designed to test Airmen on operational readiness during a simulated deployment. (U.S. Air Force photo/Airman 1st Class Anthony Sanchelli)