ELLSWORTH AIR FORCE BASE, S.D.--Staff Sgt. Jacob Martin, 28th Operations Support Squadron air traffic controller, views a radar scope, Oct. 14. Ellsworth Air Force Base recently switched from Airport Surveillance Radar to Digital Airport Surveillance Radar. The DASR technology is the newest available technology and it uses less power, requires less maintenance and manpower, and costs significantly less to operate than other systems currently in use. (U.S. Air Force photo/Airman 1st Class Corey Hook)