So I realize in the grand scheme of things this means little to many players, but the "Death from Above" achievement/trophy is absurd because of how purely based on getting lucky five times it is. Very few players use the stationary turrets, which immediately makes this achievement hard, and landing a killing blow isn't easy. I've spent about 26 hours playing the game and haven't even come close to destroying a manned stationary turret.
This would have been better as simply a 'get 5 bombing kills' type thing. For completionists, it's just aggravating.