U.S. Air Force security forces Airmen gather prior the land navigation test, during Air Combat Command’s Defender Challenge team selection at Joint Base Langley-Eustis, Virginia, Aug. 23, 2018. The Airmen competed to represent ACC during the 2018 Air Force Defender Challenge, which will be held at Joint Base San Antonio-Camp Bullis, Texas, from Sept. 10-13, 2018. (U.S. Air Force photo by Staff Sgt. Areca T. Bell)