No, no HD. They have wings, but they can't do anything more than glide at the beginning of the game, and they get a limited amount of flight time at level 5 or so. That limit vanishes when they hit 10, but it's a fly speed of 30 with average maneuverability... which isn't too great as fly speeds go. By that time, a lot of enemies will fly and most challenges can't be overcome simply by flying (because Flight and Overland Flight are both already available.)