Noob Question Regarding AA

What’s the counter to an Helirush early in the game as NATO?
When facing Red’s strategy, they often deploy AA helicopters, recon helicopters, and troop transports loaded with rockets. I’ve noticed that I tend to lose all my forces each time, trading 2-3 helicopters for each Helirush attempt. It’s especially frustrating in 10v10 or ranked matches. Probably a skill issue on my part, but I’m trying to understand the mechanics.

Additionally, I don’t quite understand how I can land multiple hits on a transport helicopter bringing it down to near death. Then it still manages to get squad out at full health. It feels inconsistent.

To put things in perspective:
It takes about 20 direct hits from AA missiles to bring down 10 helicopters, and more than half of those missiles miss their targets. Also, in Warno’s combat system, if you’re not directly controlling your AA units, they will each hit a helicopter once. Once suppressed, it will change targets

Could use some advice or insights on effective counters and understanding the mechanics better.