SELF-RESCUE U.S. Air Force Staff Sgt. William Hierholzer rescues himself during the rappel masters certification course on Camp Bullis, Texas, Nov. 5, 2010. Individuals attending the five-day rappel course learn 13 different knots, self-rescue techniques, and how to descend down a wall and safely slide down. Hierholzer is the combat leadership course instructor. SHARE: Download: Full Size (0.08 MB) Credit: VIRIN: 505076-C-TPQ68-979.jpg Photo Gallery