could you do it with the SMAW if you fire it before it locks? it's far more accurate than the RPG and would be easier to achieve, provided it still oneshots stuff.
Flares only come out for the launchers that lock on. Problem with RPG is that it can miss because it doesn't lock. So you can't hit UAV, CUAV, Lodestar, Escort Drones can be tough, etc.
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