It's just not in the Core. I thought if we included flying races we would need to spend more time in the rules discussing flight. Wings for flying will be in Creature Law, performance based on tier, e.g. tier I is 20 DP, 30'/rnd, maneuver at -10 (to your flight skill), max pace of jog I think. Tier II 30 DP, 60'/rnd, maneuver at +0, max pace run.