Exhaust and cooling water shoot out the back of the Aerodynamic and Propulsion Test Unit during a test at Arnold Air Force Base, Tenn., May 5, 2020. Arnold Engineering Development Complex (AEDC) team members are taking measures to mitigate the risk of transmission of coronavirus so they may continue performing the critical national defense mission of AEDC. (U.S. Air Force photo by Jill Pickett)