Master Sgt. James Mattingly, 361st Training Squadron aircrafts metals technology instructor, screws together some basic metals at Sheppard Air Force Base, Texas, Sept. 9, 2018. Before seeing his class graduate the next week, Mattingly wanted to perform a demonstration one last time before they go into the operational Air Force and work on real parts. (U.S. Air Force photo by Airman 1st Class Pedro Tenorio)