Ground radio and radar
SEYMOUR JOHNSON AIR FORCE BASE, N.C. -- Airman 1st Class Matthew Livingston performs maintenance on a Tactical Radio Controller 187 here July 15, 2010. The TRC 187 provides pilots with a signal they can use to communicate through secure lines with while in flight. Airman Livingston, 4th Communication Squadron transmission systems apprentice, hails from Johnstown, Pa. (U.S. Air Force photo/Senior Airman Gino Reyes)