N9584Z —

Pardon my lack of knowledge but what mechanism keeps the rear gunner from accidentally shooting-off the tail?

I believe an interrupter cam prevents firing thru the tail.

Great shot.. This was my Dad's aircraft he flew during WW2 as a Naval aviator. I had the opportunity to sit in one with him many years ago. A pretty special occasion. Never had the opportunity to fly one.

I think William is correct, similar to the WWI fighters interrupter gear ( used to prevent the pilot shooting off his own prop), just that when the gun is lined up with the tail it is prevented from firing.