How to deal with enemy planes

[Coach]

Even if i station Flak20s around my frontline, the enemy plane generally gets close enough launch several rockets thus wiping you some of my units. To make things worse, the enemy plane now crashes on my rear defensive soldiers or emplacements thus killing them..

[VirgoCompany]

I'm a singleplayer kinda fella, so when it comes to Raid or Conquest my only advice is grind grind grind out those anti-aircraft guns to shoot at everything, unlock the next AA gun, and keep going til you get the larger Flak 88's and keep them held back a bit farther with the Hold Fire order.

You'll still have to suffer putting out the less effective light flak for a while, but the quad flak on half-track mounts have a little bit more range to better deal with enemy planes (in theory). There's also the US AA emplacement that has a 37mm and twin .50 cal machineguns that has a vastly larger range than the Maxon, and the 40mm Bofors has greater range still. The Soviets have the Dshk tripod mount which has a tiny anti-air coverage area, as well as the BA-64 armored car with a weak machinegun, both can still engage and possibly kill lighter aircraft but don't count on it.

General advice:
~Just try to keep your AA guns on Hold Fire so they don't need to reload and thus waste time being unable to engage planes, they will refuse to fire upon GROUND targets but will ALWAYS try to fire on enemy planes if their Anti-Air Mode is active (it's active by default).
~Keep them facing towards the enemy's side of the map and ensure there's minimal stuff blocking their line of fire like trees and walls (knock those over with the towing transport they come with if you gotta).
~Provide overlapping protection with your guns, the mini-map will show their anti-air coverage, and a plane going into this ven-diagram of damage will be more likely to die in the sector where the two guns overlap. But be sure to spread your guns out a little bit so a single airstrike or artillery shell wipes them both out with a lucky hit and still keep some of the front line covered.
~Some Battalions specialize in anti-aircraft artillery and may be able to deploy higher ranked units in earlier echelons, as well as have discounts for said units, so if planes are your #1 concern then don't hesitate to go full hog with anti-aircraft fire, especially if you have allies who can cover you and will need cover in return.
~Check your self-propelled anti-air units, some may have limited turret traverse such as the aforementioned quad-flak half-trak the Germans have, point the vehicle's rear end towards the enemy since the gun cannot point towards the front at all. The Soviets have a small AA tank that has 5 rounds of ammo in the magazine and a slow turret rotation speed.
~Put your full-auto AA units into different Control groups, have one group manually reload after an enemy air strike is made and then have the second group reload after the first has finished, this will help ensure a fresh full magazine is loaded and ready for the next strike.

Additionally: recent updates to crew efficiency means a flak gun fully loaded with Tankers is going to be less accurate and reload slower than the same gun fully loaded with Gunners, even riflemen are not going to be quite as effective at operating the gun but they're still better than nothing.

And lastly: Sometimes that's just how it is. Despite your best efforts, enemy planes may just get their strike off and you'll lose units. Sometimes you'll shoot down that plane and it'll crash into your defenses, sometimes it will not. Sometimes you'll succeed in shooting them down before they do harm, sometimes you'll shoot them down only after they did their job. As long as you can at least shoot them down, you'll deny your opponent one plane to be used later, and that tiny victory will just simply have to do.

[Randombandit]

The towed AAA usually has a very good range. Tuck it behind a small hill or low houses that block it's LOS to ground-level threats. (a ways back from a short hill is best, so it can engage enemies that got past your front line, but not waste rounds shooting ground units). You do this because reloading and aiming the gun upwards again both take time. Note, the Air-Mode just means it will prioritize air units, it doesnt stop it from firing at ground units it sees...and it sees far.

Having shorter range stuff on the front can help mitigate over-zealous pilots when backed up by the big AAA. Remember, they do damage, they dont instakill. If one large slow shot does a ton of damage, a quad-.50 might rip the plane out of the sky before the big guns can even fire again.

Dont expect early AA to fully deny air strikes. They create a no-go zone that only encompasses a small are inside their engagement radius (because they can often fire well after taking the first hits). So think of them having about half the "protected" range of the circle they show. Your frontlines will still get hit by strikes and the prevention is utilizing the visibility mechanics and being mobile (the front lines are dangerous...). On the up side, each plane you shoot down is one less they have to use later while you AA will still be rear defense against anything that gets past your front. Early AA also tends to be great against early infantry and light vehicles, so they can push before planes even get involved.

[LappiLappland]

for small AA use direct control and shoot planes personally
seems like AI in this game is programmed to have worse aim than direct control can offer

[VirgoCompany]

Originally posted by LappiLappland:

for small AA use direct control and shoot planes personally
seems like AI in this game is programmed to have worse aim than direct control can offer

We would like to do so, unfortunately it's not all that viable since planes will be moving quickly and zoom off the screen. Even the newer first person view and over-shoulder view are not going to help since the camera has a very VERY limited upwards viewing angle, meaning it's going to struggle aiming at units higher up on a small hill and be nigh-impossible to hit any planes.