Flying Tigers: Shadows Over China

This can easily be done, by selecting a dogfight mission from the main menu. You can choose time of day, and select just one enemy. Now all you need to do is start the dogfight and destroy the enemy for the achievement.

From the Main Menu select Singleplayer and then Dogfight.

Choose a fighter that you like and is powerful. The "Six-Shooter", "Lightning", and "Shooting Star" are all great fighters. For the enemy, choose the "Rufe" which is the seaplane under the Japanese options. (Press X to change faction).

Choose AKYAB as the location.

You can use any settings for control and difficulty, but "Casual" makes this very quick. Leave location as "AKYAB", weather as "NIGHT" and choose "3" enemies.

Start the match and shoot down the 3 fighters and the achievement should pop!