I seem to be a little confused over Airships. It seems sometimes they can bomb an enemy ship and sometimes they can't and I can't understand a reason why. They are in range (within 8 squares) but the selected square to hit is greyed out when I hover over it, yet the Airship can carry out a Recon of it's full area.

Do they only have a certain amount of times they can fire on a target?

They have a max amount of damage they can do to any enemy (not just ships), i think its 50% of the base strenght. When the strenght of the enemy drops below that the airship is unable to attack.

Aaah, I see, thanks for that.

Their damage limit is a measly 20% off the base value, and they can't bomb cities or improvements.

Only 20%??!?? :sad:

Ah well they are still ok as recon units, and even the 20% can help alot when weakening the first defenders before your artillery comes moving in for the colleteral. The big advantage of them when they become available is ofcourse that nothing can really stop, its free damage.

It used to be 30% pre-3.17 patch... I updated to v3.17 but kept the percentage at 30%... I felt airships were nerfed enough.

What is worse is that a strike by an Airship does not always do the maximum 20% damage. For example, you're attacking a city with 40% cultural defence, on a hill, defended by a Longbowman and a Pikeman, both with CG2 and fortified to +25%, and you want to attack with Cavalry. The LB begins with +160% bonuses, the pike with +110% rising to +210% against cavalry: direct attack with a Cavalry (str. 15) would be met by the pike at a strength of 18.6, so goodbye cavalry. Now strike from an airship; the LB is the stronger defender but takes only 18% damage, leaving him at 12.78 which is still stronger than the pike at 12.6. So a second airship attack hits the LB again and this time does just 2% damage, now just below the pike which a third airship strike would attack. Even if that did do the full 20% damage, the pike would face cavalry with an effective strength of 14.88 against the cavalry's 15.
And if the defending city has two longbowmen, it would probably take 4 airship strikes before the pikeman could be attacked by a fifth airship.

Attacks by bombers/airships/fighters etc, don't necessarily do maximum damage in a single strike... that's not the intent... that's supposed to represent the most damage that can be taken-off a single unit by that type of attack... so if an airships' maximum % of damage is 30%, that means that a 10-str unit can't be reduced below 7-str by means of airships... it might take one airship to drop it from 10-str to 7-str, or it might take three or four airship attacks... in any case, if the maximum % is 30%, then then no attack by airship can drop that 10-str unit below 7-str.

Like I said... it used to be 30% and Firaxis nerfed it down even lower to 20% in v3.17, which I thought was too little to be of any real use... so I left airships at 30% in my own mod.

which I thought was too little to be of any real use...

Oh, how true !