Just today, in my WW2 Soviet long campaign, I provided the AI with a beautiful target - 6 KV1 nose to tail along a road, with SMG sections mounted on each, and some T-34 nearby who had just dismounted, but all a tight-packed horde. Complacent. moi?

!.
Anyway, I got attacked by around 6 ME-109. Mixed rocketeers and bombers. Results were 1 KV routed with its main gun shot off, and 2 stuck with busted tracks and a point of damage. About a company of SMG gunners running for home with severe headaches, and 3-6 points of damage for most of them. 3 M5 halftracks and 2 ZSU-37 trucks damaged one plane a few points.
later, the remaining planes strafed my guard mortar battery, and a pair of SP-37mm nearby damaged one, while they did a point or so of damage to a guard mortar MRL truck.
Air is not an uber weapon in WW2, nor is flack a sky-sweeper.
But I should have gone tactical with that KV column a move or so earlier..
If you expect air around, then the best way to deal with them is to spread out a min of a hex apart.
Cheers
Andy