DETONATION LINE DEMO U.S. Air Force Staff Sgt. Patrick Heltne, left, observes Staff Sgt. Darryl Wilcken wrap a detonation line on Ellsworth Air Force Base, S.D., March 30, 2010. Heltne and Wilcken are explosive ordnance disposal journeymen assigned to the 28th Civil Engineer Squadron. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 141351-V-JIK77-500.jpg Photo Gallery