My way every prestige and thi still works on the latest patch is to get put sleight of hand pro, coldblooded and steady aim then use a L86 LSW and an AT4. You can do it on a pave low of attack helicopter doesn't matter just its easier for the attack heli. So you shot the first AT4 at the helicopter then shot at it after a clip it'll start spinning just reload and shot it for 100 shots and thats it your have the pro