Don Campbell, a pilot for more than 30-years, took several members of the press thousands of feet in the air Thursday morning. He pointed out different landmarks and roads where the Amgen Tour of California will be held Sunday. The roughly 30-minute flight passed over Auburn, Grass Valley and Nevada City. The number of pilots in the air has been free-falling in the last few years, he said. Campbell, Sierra Vista Aviation founder and flight instructor, said 70 percent of flight students worldwide don't finish their flight training. "It boils down to the economics," he said, adding that completing pilot training can cost up to $7,500. Add that to the cost of fuel at $4.95 per gallon and th