Flying units have to make a morale check to fly over enemies, and the more there are the harder, but thats pretty rough. That guy just can't get a break.
Seems like Jarvis got airshield researched at the exact right time, as far as I saw he never used it until the final battle against Caelum.
This is looking like the second game in a row going to the wolfmans. Guess we'll have to start planning on killing them first in future games.