it would be like fighting over a cv all the time.
i think there should be a flak nest hidden somewheres around a field, that only reveals itself& opens fire once the ack is down on the field.(kind of like a last line of defence)
or maybe just give the Town flak cover.
but Flak over fields would get annoying quick. just go have a furball over a CV or city, and you'll know what im talking about.