TUCSON, Arizona: A ten-mile circle on a snowy Colorado mountain is now the target of the search for Air Force Captain Craig Button and his runaway plane. Working with FAA radar tracks and several eyewitness accounts, the Colorado Civil Air Patrol has placed Button's A-10, an $8.8 million plane loaded with four 500-pound bombs, on New York mountain, about 20 miles southwest of Vail. The mystery of why Button left the Arizona-bound flight path of his three-plane team has raised speculation that he might have purposely broken away. There have been several incidents of military air tragedies that occurred when pilots wanted to dip their wings over their girlfriend's house or put on an air show for one of the pilots' parents, notes TIME's Mark Thompson. "But in the military, you don't go off course to do that. Button's team was supposed to go to Arizona. And Button went to Colorado. Deliberately changing the flight plan gets you kicked out of the military very fast." Air Force officials say that the bombs were unlikely to explode on impact, and dismiss speculation that the plane, nicknamed Warthog, was sabotaged or stolen for its weaponry. "The Air Force, quite rightly, is refusing to voice questions about Button's record," says Thompson, "because if a pilot ever innocently found themselves in a situation like this, that pilot needs to know that the Air Force isn't back in Washington showing their personnel records around. The Air Force's first concern right now is with the safety of the pilot, and then with finding the plane."