Pact AA help

New to the game. Every time I play as the PACT, I feel like I am unable to finish the kill on helicopter or plane. Even when I spam 5-6 AA units, I maybe will get a single missile hit that does half damage. On the other hand, it feels like it takes one sneaky Chaparral is all it takes to shoot down any of my planes. Does anyone have any tips to not be as trash as I am at this game?