Generally speaking, only tanks have worthwhile AVs, almost all lighter vehicles ranging from Armored Personel Carriers, Infantry Fighting Vehicles and Tank destroyers tend to have AVs of between 0 and 3.
All infantry types, as well as most helicopters and planes have 0 AVs for all sides, however many Warsaw Pact transport and gunship helicopters tend to have an AV of 1 for their front and sides (the most notable example being the Mi-24 Hind series), the only NATO helicopter with an equivalent AV value would be the AH-64 Apache. Ka-50 and Ka-52 helicopters have armor covering front, sides and also the rear to represent their lack of tail rotor weakness.
Only 3 aircraft (4 counting national differences) have AVs above 0, all are ground attack aircraft and the AV enables them to survive most hits from anti-aircraft fire, they are:
- A-10 Thunderbolt II - United States, their front/side/rear/top value is 2/1/2/1
- Su-25 - Soviet Union and Czechoslovakia, their front/side/rear/top value is 2/1/1/1
- Su-25T - Soviet Union, their front/side/rear/top value is 2/1/1/1
One very important thing to note of is that units will only fire on other units if the AV is the same or lower than the armor piercing (AP) value of their weapon, if the AP is lower than the AV, than the unit will not fire and manually commanding them to do so will only result in the "Inefficient!" sign.
After much testing was done by some wargamers, an equation that links AVs to armor piercing (AP) values has been discovered, it is:
Damage=[(AP - AV)/2] + 1
With this in mind, a shooter with an AP the same as the AV of the target will always do at least 1 point of damage to the target.
Another point to take note of is that Weapons with the [HEAT] attribute will ALWAYS do at least 1 point of damage no matter the armor rating of the vehicle, so ATGMs and LAWs can always do damage to their targets however small it is. This effect does not stack with the +1 of the armor/damage equation, so a weapon with the [HEAT] attribute will still do 1 point of damage to armor of equal value. Additionally, HEAT with AP greater than 10 over the AV will begin doing additional damage, doing 1 damage per AP.
It is also important to keep in mind is that if the target has an AV of 1 or 0, then a weapon with a [KE] attribute will do 4x the damage of the base AP, while a weapon with the [HEAT] attribute will do 2x the damage of the base AP. (Read Weapons to find out more about the [KE] and [HEAT] attributes)