You would still be vulnerable from the underside. And a gunner would only disperse the attackers. Shooting them down is a lot harder.
TBH, I find the design a bit awkward, due to trying to cram a rather large turret on a fairly small spaceframe. What I would do instead is elongate the viper a bit, make it a two seater, and make a small rear turret on the underside that is controlled from the gunner's position inside the cockpit. Yes, you can have a system in place that prevents you from shooting off your tail, but it comes at a price of significantly reducing your firing arc, creating a blind spot exactly where you don't want it - on your six. This would make the turret a bit useless since most of the attacks would come from the rear - and I assume the turret would come at a price of something else (acceleration, maneuverability, or whatever). So you really want it to carry it's weight as opposed to being dead weight
Newman, thanks for your feedback on the concept, it is appreciated.
As I stated before, I intend to make it a sort of fast strike bomber with limited anti fighter capability.
Think of it as a WWII dive bomber. and they were not much bigger than a fighter.
And though your statement about the rear attacks is true, there is a tactic that was used.
The bombers would fly in formation so their guns would protect each other.
Indeed, 1 bomber is very vulnerable. 3 is better. But when you get 15+ bombers in close formation, you will have to use good tactics to attack and get through unharmed. And then you would not have much time to kill.
Stay in the formation to long and you will be shot to pieces.
And in dire need the bomber would turn away, giving the gunner a better shot.
And about the tail, maybe I make a V tail out of it... or a double tail like the BF 110 or the B25.
Everything is still subject to change.
And Ideas from you guys is allways welcome.
(sorry for my late reply. school is keeping me busy)