Senior Airman Rashion Walker, 28th Aircraft Maintenance Squadron communication/navigation systems technician, tightens electrical lines during equipment upgrades on a B-1 bomber’s radar system at Ellsworth Air Force Base, S.D., April 11, 2012. The 28th AMXS Avionics Shop technicians installed new processors and receiving units on the radar systems, then tested the system to ensure the new parts worked properly. (U.S. Air Force photo by Airman 1st Class Alystria Maurer/Released)