U.S. Air Force security forces airmen set up a 3-D

U.S. Air Force security forces airmen set up a 3-D grid to show the terrain and route they will take during a training mission at the Ranger Assessment and Selection course, Oct. 21, 2011, at the Nevada Test and Training Range. Airmen must attend the RAS course before going to the U.S. Army Ranger School, designed to train armed forces personnel to conduct combat operations within enemy lines.