Few industries are hit as hard by high oil prices than the airlines, which can spend close to 40% of their budget on fuel. With jet fuel prices near record highs, the drive to conserve is stronger than ever. Delta recently made headlines with its novel bid to buy an oil refinery, taking a more direct role in procuring fuel. But Delta and other airlines are experimenting with a number of other ways to cut costs. The entire industry is hoping a switch from radar to GPS-based navigation will cut the time it takes both to reach cruising altitude and land a plane.