[Imp]

Unless its changed firing ATGMs at helicopters can only happen if it remains stationary, can be far more accurate than dedicated AA missile as ignores EW rating, moving one hex every turn prevents ATGM use.

Not come across issue with damaging probably because dont fire main guns ATGMs at helos often, not bothered to test but like anything in this game you can get a lucky or unlucky roll dependant on your viewpoint.