The scans for ch.12 are now on Alphapolis' server, but once again, the link for the online reader is still unposted.
Spoiler:
Yep, Apocalypse Now chopper attack indeed - the gunship fleet turns the entire siege force into mincemeat and the spectacle is (it didn't click well with me, though) inspiring enough to make some of the besieged locals think of the legendary Valkyries (which should be a Norse thing, not a Roman one -- the author shouldn't have muddled the cultural barriers so much IMHO).
Even on the ground the imbalance of power is shown, as the recon troops manage to punch through an imperial
scutum with their standard-issue rifles. No more bullets? No problem! We've got grenades, handguns and bayonets to fend off attackers - not to mention a monstrous axe-wielding Loli whirling like a demonic dervish in our immediate vicinity. No sweat, no loss.
As an added bonus, the chapter is longer than the last one.