DOVER AIR FORCE BASE, Del. -- U.S. Air Force Airman 1st Class Matthew Trees, 436th Maintenance Squadron metals technology apprentice, uses an angle grinder to smooth out the edges of a cart on Dover Air Force Base, Delaware, June 4, 2026. Metals technicians use welding, machining, heat treating and fabrication techniques to repair damaged aircraft components. (U.S. Air Force photo by Airman 1st Class Macy Dismore-Mann)