U.S. Air Force aerial porters of the 921st Contingency Response Squadron, Travis Air Force Base, Calif., have a briefing before working at Grant County International Airport, Wash., during Exercise Mobility Guardian on Aug. 4, 2017. More than 3,000 Airmen, Soldiers, Sailors, Marines and international partners converged on the state of Washington in support of Mobility Guardian. The exercise is intended to test the abilities of the Mobility Air Forces to execute rapid global mobility missions in dynamic, contested environments. Mobility Guardian is Air Mobility Command's premier exercise, providing an opportunity for the Mobility Air Forces to train with joint and international partners in airlift, air refueling, aeromedical evacuation and mobility support. The exercise is designed to sharpen Airmen’s skills in support of combatant commander requirements. (U.S. Air Force photo by Staff Sgt. Kyle Brasier)