Airman Logan Talley, 361st Training Squadron aerospace propulsion apprentice course student, replaces a lube and scavenge pump on an aircraft engine at Sheppard Air Force base, Texas, Jan. 31, 2018. The lube and scavenge pump regulates oil flow to the engine. Talley is in block five of five and scheduled to graduate Feb. 8. (U.S. Air Force photo by Alan R. Quevy)