The B-29 bomber was the first production bomber aircraft to use a central fire control system. According to the manual, it's advantages were:

It permits the most effective location of guns and gunners
Loss of a sighting station does not mean loss of a turret's fire power
The turrets impose less drag on the airplane
Sighting accuracy is increased
A gunner's personal comfort is increased
Protection for the airplane against damage from its guns
Remove location of important electric equipment means better protection for it and less maintenance
Facilitates proper weight distribution
Simplifies pressurization of the airplane
The system consisted of 5 turrets (Upper-forward, Lower-forward, Upper-rear, Lower-rear, and Tail) and 5 sighting stations (Nose, Upper, Right-blister, Left-blister, and Tail). The system allowed a single gunner to train, track, and fire multiple turrets on a single enemy target.