It’s like a 3-dimensional Sailing race. The pilots race a course in the sky, which may be a triangular course or an “out and back”, or maybe a straight “race to goal”. Pilots are scored on how fast they fly the course, or how far they went if they did not finish the course. Global Positioning Systems (GPS’s) are used to navigate and as track logs of each pilot. GPS’s also give each pilot a synchronized time.