The following can be unlocked by completing various tasks in the game.
Complete the following achievements to unlock Xbox Live Gamerscore points.
Complete the indicated task to unlock new aircraft colors. Note: To change aircraft colors, first purchase a color scheme from the hangar. Then, highlight a particular plane and press Left or Right to select the other color schemes.
Successfully complete the indicated task to unlock the corresponding aircraft
Successfully complete the game to unlock the "Music Player", "Scene viewer", "New Game SP", and "Expert Difficulty" options. Additionally, by completing the game 100% and then finishing the newly available downloadable content, "Ace Of Aces" mode becomes unlocked.
If you are going for an "S" rank, take the time to use Allied Attack and Cover to take out some of the UAVs that Pasternak uses to attack you and your squadron. After you have killed about five of the UAVs, concentrate your fire on Pasternak. He is always visible with ESM. This should give you an advantage. Later his ESM will disappear. Pay attention to your radar and use the Right Analog-stick to look around for him.
If you are going without an "S" rank, use Allied Attack directly on Pasternak so that your squadron keeps him busy while you take the shots on him. He always stops to fire his ADMMs; use that as an advantage to your Allied Attacks and missile attacks.