I have combined a video guide for 2 trophies/achievements in this video, Flyswatter (destroy 8 enemy helicopters in the mission 'Heat') and Bird On The Ground (Shoot down an enemy helicopter with an RPG in the single player campaign). So first off you need to get to the part of the mission where you use the mini gun in the shot down helicopter, take out a few ground troops for the first 5 helicopters to spawn in. Quickly dispose of these, they aren't hard to shoot down on recruit difficulty. Then move on to the second part where the mission takes you to the barn, instead of running all the way over grab the RPG that is leaning up against the fence, turn around and 3 more helicopters will be dropping troops off, make sure to blow these up from left to right as the left one flies off first. Also be sure to grab all 3 rockets (like i don't do first time in this video!). Should you fail at this point simply restart the checkpoint and try again :) If this video is any help to you please like, drop a comment and be sure to subscribe to my channel, more Call of Duty 4 Remastered content to come. Thank you!