As the title states how can one make those poor air units gain some exp points? This problem is keeping me awake lately, and I wanted to do something to solve this annoying issue.

I tried to learn something from The Air Forces Mod, but with no luck. I still don't know which values I would have to change for my planes to gain any exp. Very frustraiting!

Can anyone help me with that?

Bro, look for TheLopez Air Force Mod. Works perfectly.

I know it does.
But I would like to know more about the mechanics that allow planes to gain exp. The thing must be somewhere in these files: CIV4PromotionInfos.xml, CIV4UnitInfos.xml or even somewhere else(?)

I need some help and I'd be grateful for any.

The changes lays not only in .xml but also in SDK (compilled .dll) - Lopez marked places where he put text with comment- so it isn't hard to find

you may use some software that compares files like Winmerge (my favoured pspad also has this option)

Thank you asioasioasio!
But unfortunately I still don't get it, my apologies. I'd have to see a step by step instruction of what I have to do; like first do this, then open that... If that is possible of course, you know I'm just a beginner and get confused easily.

But want do you want to do - just use it as mod - or if you want add the mod to your own mod i need to know if you have .dll already in it or not.

No I don't. No .dll as far as I'm concerned. Frankly I didn't know I'd need that file at all.

so just take .dll and compare your xml files with that you use and copy the changes

Ok, so I just decided to modify the mod by TheLopez to suit my needs.
Thanks to everyone for the help and suggestions of what to do.