Dragon Racing

How a dragon flies

1. Steer. Twenty times a second your spell answers with a turn from -1 (hard left) to 1 (hard right) and a thrust from -1 (a back-beat of the wings, to brake) to 1 (full wings).
2. Momentum. Full wings carry a dragon to about 120 units a second. The faster it flies, the wider its tightest turn: a bend has a top speed, the square root of 90 times its radius. Come in too fast and it runs wide.
3. Drift. A dragon's heading swings at once, but its flight follows only as the drift fades, and the sideways speed is lost. Off the track, in the bracken-cloud, it slows hard.
4. The lap. From a standing start behind the line, once round, through every stretch of the track (cutting across does not count). A lap not done in 90 seconds does not count.
5. Records. Your best lap of each track is kept, with its ghost, for everyone to race. Experience comes for a first lap, for each medal, and a little for each new best, for a spell of your own.