U.S. Air Force Senior Airman Mikel Columbus, 4th Communications Squadron ground radar technician, instructs Maj. Nelson Avilesfigueroa, 4th CS commander, how to safely rappel down a 100-foot tower at Seymour Johnson Air Force Base, N.C., Nov. 6, 2013. Columbus instructs Airmen during annual climbing certifications to ensure proper technique and safety. (U.S. Air Force photo by Airman 1st Class Aaron J. Jenne)