11th Wing Airmen hold defensive fighting positions during the Ability to Survive and Operate exercise at Joint Base Andrews, Md., Jan. 25, 2018. The ATSO exercise was comprised of several stages, including holding DFPs, applying self-aid buddy care, properly donning mission oriented protective posture gear, and identifying and cordoning off unexploded ordnances. (U.S. Air Force photo by Airman Michael S. Murphy)