In-flight testing is conducted to certify a Negatively Pressurized Conex prototype on a C-17 Globemaster III, April 30, 2020. The NPC is designed to transport individuals with the COVID-19 virus and other highly infectious diseases, all while preventing the aircrew and medical professionals onboard from being exposed. (U.S. Air Force photo by Staff Sgt. Chris Drzazgowski)