Here is the full list of all 12 Top Gun achievements.
Complete all the Indian Ocean Missions.
Mission 4 (1st playthrough – Viper wins).
Jester is shot down at any point by either you or your wingman.
First plane locked onto with missiles when in CFI and then successfully killed.
Awarded after 3 afterburner boosts.
Mission 4 (2nd playthrough – Player wins).
Complete all of Prologue, Top Gun Academy and Indian Ocean with all planes (any difficulty).
Complete any one of three hidden flight runs.
Complete all 3 of the hidden runs.
99 kills in Multiplayer (with Missiles or Guns).
Rewarded for more than 10 gratuitous deaths in a single multiplayer match.
Be the first to get the star in a multiplayer match, and hold on to it until the bitter end.