ELLSWORTH AIR FORCE BASE, S.D. -- Senior Airman Caleb Christian, 28th Maintenance Squadron repair and reclamation journeyman, tightens bolts on a tire using an impact wrench, March 24. Repair and reclamation personnel use a one-man-build stand to hold the tire in place while they repair it. (U.S. Air Force photo/Airman 1st Class Matthew Flynn)