U.S. Air Force Tech. Sgt. Matthew Heiser, 49th Security Forces Squadron flight chief, performs tire flips during Air Combat Command’s Defender Challenge team selection at Joint Base Langley-Eustis, Virginia, August 24, 2018. The Airmen performed a variety of exercises, including flutter kicks, jumping jacks and sit ups during the assessment. (U.S. Air Force photo by Airman 1st Class Anthony Nin Leclerec)