(A usable air defence artillery.)

(Apparently, it can only be used by the members of the Asmodian legion that took the fortress.)

(The air defence artillery seems to be in order.)

You use the air defence artillery. You finish the investigation.

(A usable air defence artillery.)

(Apparently, it can only be used by the members of the Asmodian legion that took the fortress.)

You finish the investigation.

(A usable air defence artillery.)

(For some reason it isn't working properly.)

You finish the investigation.

(You successfully use the flak artillery.)

(You can now use the flak artillery skills.)

You finish the investigation.