Sunwing is a level 51 rare Dragonhawk found in the Burning Steppes. It’s the only tameable Dragonhawk to use the black skin and is definitely my favorite. It’s fairly new to the game, just being added in patch 5.1. The Dragonhawk’s special ability is Fire Breath (magic vulnerability) and it looks like it’s staying that way for Warlords of Draenor.
Sunwing spawns at roughly 10,53 near Flamestar Post. If you are Alliance, this is only about a 30 second flight from Stormwind, so it’s very easy to check and see if he’s up. The respawn time seems to be around 4 hours, give or take. I see him up pretty frequently when I take trips to Blackrock Mountain.