A little while back, CinemaBlend broke the news that Ubisoft had set up a tips and tricks website for Tom Clancy's H.A.W.X. gamers.
The website has mission walkthroughs, handling tips for each aircraft, info on how to unlock weapon sets, and more. Simply log in with the information that you used to link your copy of H.A.W.X. or Rainbow Six Vegas 2.
H.A.W.X. isn't really that difficult to begin with, but it never hurts to have help. Think of this as the Devon Miles to your KITT.