GROUND GUIDE U.S Army Sgt. Christopher Carter signals to the driver of a Heavy Equipment Transport, or HET, as they load it onto a trailer while preparing for convoy operations during training at Camp Atterbury, Joint Maneuver Training Center, Ind., June 20, 2008. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 108523-A-YFR68-765.jpg Photo Gallery