The first unit of this class, the Anti-Aircraft Gun, becomes available at the Factory in the Industrial Age, along with the first fighter planes. Production and upgrading of Anti-Aircraft units costs both Food and Wealth.
|Industrial Age||Anti-Aircraft Gun||Anti-Aircraft|
|Modern Age||Anti-Aircraft Battery||Anti-Aircraft|
|Information Age||Anti-Aircraft Missile||Anti-Aircraft|
Anti-Aircraft units are the mobile variant of the stationary Air Defenses, which are an upgrade of the earlier Lookouts and Observation Posts. While the latter ones are more effective in defending cities, outposts and wonders, Anti-Aircraft units are supposed to accompany armies and protect them from enemy air raids. Depending on enemy air power, try to bring at least 3-5 AA units with an attacking army, otherwise you might lose important units such as Generals, Supply Wagons and Artillery Weapons to enemy air raids.
The British build Anti-Aircraft units and buildings 25% cheaper and 33% faster.