Airmen Work Airmen assigned to the 60th Aerial Port Squadron use a 35-ton bridge crane to load a negatively pressurized conex onto a Tunner 60k loader at Travis Air Force Base, Calif, Aug. 5, 2020. The NPC is an isolated containment chamber designed to safely transport up to 30 passengers -- including 24 walking patients or eight patients on stretchers -- affected by infectious diseases such as COVID-19. SHARE: Download: Full Size (3.57 MB) Credit: Lan Kim, Air Force VIRIN: 200805-F-SK304-0032M.JPG Photo Gallery