Because at the games core it's still a WW2 simulator. Those aren't high powered Jetfighters, they are ME262's and Gloster Meteors at best.

1) What size is your airforce?
2) What planes are you using?
3) Do you have static AA along with Radar?
4) Are all air zones covered? Even rivers are airzones.

Also Legion doesn't use prop planes, they use the airships, which have a higher attack than regular planes.

I see, a figured jetfighters would have been superior to prop planes
At the start I had 1200 planes roughly before they were wiped out, the planes are the jetfighters from lockreed completing open for business focus. AA I have not made but have some radar far from my Capital and no I was not aware about the air zones.

Ah, the legion zeppelins destroy even xian85 fighters 100 vs 100
and legion have thousands of then.

So I win this war by adding AA to all divisions and push throw legion land without air supremacy, using only the power of overcoming (manpower lost will still be lesser, when if you try to destroy all legion airforce).

Also use sigma to give air penalties to legion

The F85's are a trap honestly. Their production cost does not offset their stats. Which is also a problem in Vanilla HOI4.

It's more a fight, but even the P80 Fighter and/or P51s can hold their own in a dogfight if given sufficient numbers.

I have quit the game and deleted the saves, I will try again after the June update. than kyou for your advice.

Well, even with AA it doesn't help much when legion has +1k of them, 80 damage done to everything + infrastructure gets wrecked almost instantly just due to sheer numbers even with NCR peacefully joining you on Nevada path, its basically required to start mass producing heavy fighters ASAP to deal with that crap to actually push

引用自 soldiersPL：

Well, even with AA it doesn't help much when legion has +1k of them, 80 damage done to everything + infrastructure gets wrecked almost instantly just due to sheer numbers even with NCR peacefully joining you on Nevada path, its basically required to start mass producing heavy fighters ASAP to deal with that crap to actually push

Only PA can assault on legion territories. regular infantry are too weak for this

BECAUSE THE LEGION ALWAYS WINS! Ave, True To Caesar!