U.S. Air Force Col. John J. Allen Jr., 633rd Air Base Wing commander, greets Staff Sgt. Thomas Wright, 633rd Medical Operations Squadron ultrasound noncommissioned officer in charge, at Langley Air Force Base, Va., Oct. 20, 2014. Members of the 633rd MDOS returned after constructing an expeditionary field hospital for the U.S. Public Health Service in West Africa. (U.S. Air Force photo by Senior Airman Kayla Newman/Released)