DoD Mask Wear: On DoD Transportation Assets & DoD Transportation Hubs
"d. Transportation: All individuals, regardless of vaccination status, must wear a mask on DoD transportation assets (e.g., planes, water transport, buses, trains, taxis, and ride-shares) traveling into, within, or out of the United States, and indoor DoD transportation hubs."
"These requirements apply whether the DoD transportation assets and hubs are located inside or outside the United States, but exclude ships, submarines, aircraft, and other tactical vehicles and craft in their operational environment."