How does flak cannons work?

[LordLothar]

I'm wondering how the flak cannon works. Is it only effective in the square that is attacked? How many do you need for maximum effect? And is it viable to bring it along your mobile army to have protection from the air?

 

[Pfeffersack]

Yes, they only protect they square they are one and it is effective to take them with your army since the AI loves to bomb troops in open field in conquests.4 of them on a tile make effect, more are only useful as reserve in case one is destroyed.

 

[Longasc]

I think someone posted the formula how Air Defences work.

I would also be interested how the city improvement SAM Site works.

 

[Ginger_Ale]

Read this similar thread in Civ3 GD and this comprehensive study by BomberEscort on Anti-Aircraft formula.

And yes, they only work on the one tile they are on, as Pfeffersack said.

 

[sourboy]

All anti-air is 4 per tile max, for defenses. Ground air defenses work only on the tile it resides on, fighter planes also cover neighboring tiles. All chances are relatively low, but stack with up to 3 more, per enemy air run. So basically, bring 4 along with your big stack of troops, or don't bother at all.