Airman 1st Class Colin Glennen, 74th Aircraft Maintenance Unit (AMU) crew chief, closes a panel on an A-10C Thunderbolt II Nov. 14, 2019, at Moody Air Force Base, Ga. As a crew chief, Glennen is responsible for servicing liquid oxygen (LOX) systems on the A-10. LOX is used as a continuous supply of breathable air to pilots and aircrew at high altitudes. (U.S. Air Force photo by Airman Azaria E. Foster)