Senior Airman Dustin Harris, left, and 1st Lt. John Day, center, discuss radio frequencies with a Soldier assigned to the 82nd Airborne Division during an exercise in frequency hopping at Fort Bragg, N.C. Frequency hopping is changing regular frequencies during transmission, a radio operation technique that ensures secrecy and protects against communication channel jamming. Day and Harris are tactical air control party members with the 14th Air Support Operations Squadron. (U.S. Air Force graphic/Robin Meredith/Photo by Airman 1st Class Alexander Riedel)