Steve Watkins, one of the longest-tenured flight instructors in the U.S., changes the fuel on his Cessna 150.  A gallon of gas costs him $5.50, but he still offers very low rates to teach students to fly.  “In real life I’m subsidizing flying for somebody," he says. "But for the younger guys that are trying to start accumulating hours for a career, paying it forward doesn’t hurt you.”