Ace Combat: Assault Horizon

You get this achievement after you do the bombing run and destroy the run-away ICBM (mission 11 AKA Launch), When you get the the ICBM part, Try to stay out of its flames, and hit it with your guided missiles and your secondary missiles (choose the 4 air to air missiles they help a lot), shoot your primary missile off, then switch to your secondary missiles and shoot them off, keep repeating this and it will explode giving you the achievement. Also you have to be in DFM (Dog Fight Mode) it also helps if your circle is full red before you shoot off your missiles it improves your missiles accuracy, and if you do not keep up with the missile it will give you mission failed.
Good Luck

The only important thing towards this is. Don't get spotted by the radars! Stay on the deck and manouver a lot and you'll be fine. This is during the bombing mission where you can choose the B1 and the B2.