Alright, as many bombers have, the Falcata and Praetorian being examples, rear-firing turrets, they have no practical use.
Using them effectively would require one to fly in a straight line with someone behind and not firing.
I don't exactly have a problem with them, but what is the purpose?
A way a lone a last a loved a long the riverrun, past Eve and Adam's, from swerve of shore to bend of bay,
brings us by a commodius vicus of recirculation back to Howth Castle and Environs.
A valid point however you can use em to kill npcs and incoming missiles, and not necessarily a straight line just change your view and you can fly and use back turrets
RAHF.Lt.Karol.Olsav
fmr Lord Solar Admiral of the Helghast, fmr.RAHF-Olsav-[Cpt], fmr. {Helghast}(LSA-vhf)~Olsav, fmr.{Helghast}(LSA)~Olsav, aboard HCS. Kesselring
When making a pass in a joust you can hit rear view and shoot your opponent while they're turning and helpless. Usually they are pretty worthless, though.
With the Falcata, the rear turrets can fire sideways as well, so you can effectively broadside a fleeing trader or something.
I never saw a lot of use for them, especially on VHFs when you have only one, and chances are that if you're in a VHF you're going to be shooting at something that won't take a lot of harm from a single turret.
Single rear-firing turrets are a bit confusing. They often aren't good enough to do any significant damage to a target that your VHF would be running away from anyways.. This is one of the reasons I like the Dagger, Scimitar and Sabre. The turret on these ships fire forward.