Staff Sgt. Joshua Jones, 362nd Training Squadron instructor, shows his class the proper placement of a jack during a nose wheel replacement on an F-15 Eagle at Sheppard Air Force Base, Texas, Dec. 14, 2017. Jones’ class is in block five of six of the F-15 crew chief apprentice course and scheduled to graduate Jan. 30, 2018. (U.S. Air Force photo by Alan R. Quevy)