Originally Posted by
barnstormer1968
The original Viet Cong manuals (well in reality often drawn on cardboard or wood) showed how to aim RPG's for example, and then were updated to show in pictorial form how to aim such weapons at helicopters in differing flight regimes
But this was not foolproof. The luckiest helicopter pilot alive had descended into a clearing only to find a VC pointing an RPG7 at him. He took careful aim then swung 2 helicopter lengths to the right before firing.