ZIPPING ALONG A U.S. Air Force Reserve pararescueman uses zip-lines during high-altitude rescue training on Cape Canaveral Air Force Station, Fla., Jan. 20, 2011. A zip-line consists of a pulley suspended on a cable mounted on an incline. SHARE: Download: Full Size (0.09 MB) Credit: VIRIN: 078656-D-GZI10-928.jpg Photo Gallery