U.S. Air Force Airmen ruck march during Air Combat Command’s Defender Challenge team selection at Joint Base Langley-Eustis, Virginia, August 20, 2018. Six Airmen were chosen to represent ACC during the 2018 Air Force Defender Challenge in the hopes of winning the Sadler Cup, which is named after Maj. Gen. Thomas Sadler, who served as Air Force Chief of Security Police from 1975-1977. (U.S. Air Force photo by Airman 1st Class Anthony Nin Leclerec)