RESEARCH and DESTROY

Due to the randomness of the game you might start with the Rocket Booster Launcher or you may have to research it. Either way, once you have it make sure you are on the Solo Booster Configuration by pressing RB so it says Solo Booster on the bottom right. Just target the ghosts and watch them fly. I did notice that on the successful ones it seemed to lock on to them.

I got this by starting a new game until I got the Solo Booster Launcher and ghosts on first map then was able to get 13 before competing objective since it only spawns ghosts.