U.S. Air Force Lt. Col Kevin Parsons, right, 93rd Air Refueling Squadron commander assigned to Fairchild Air Force Base, Washington, performs a preflight inspection on a KC-135 Stratotanker while wearing an Aircrew Eye and Respiratory Protection System (AERPS) Sept. 16, 2019, at Fairchild AFB during Exercise Mobility Guardian 2019. Exercise Mobility Guardian is Air Mobility Command's premier, large scale mobility exercise. Through robust and relevant training, Mobility Guardian improves the readiness and capabilities of Mobility Airmen to deliver rapid global mobility and builds a more lethal and ready Air Force. (U.S. Air Force photo by Staff Sgt. Dustin Mullen)