To get an easy seven kill streak, do not call in your helicopter right away. Instead, go out on a suicide mission and die. Once you respawn, find a good hiding location and call in your helicopter. Every kill your helicopter gets will add onto a kill streak. If your helicopter gets three kills you will get a UAV, five kills for an airstrike, and seven kills for another helicopter. Dying and finding a good hiding spot is important because, ifyou die at any time during this, your helicopter will not count towards a kill streak anymore.