OBSTACLE COURSE U.S. Air Force Staff Sgt. Jason Albrecht runs military working dog, Markey, through an obstacle course during an obedience training session on Shaw Air Force Base, S.C., July 13, 2011. The 20th Security Forces Squadron military working dog trainers train and prepare dogs to participate in drug raids, patrols, and other specialized mission functions. SHARE: Download: Full Size (0.07 MB) Credit: VIRIN: 994412-R-YAL79-656.jpg Photo Gallery