44. When an electricity generating plant features shaft-driven generators, what type of propulsor is generally used for main propulsion?

Controllable-pitch propellers maintain constant shaft RPM for generator frequency while adjusting ship speed by varying blade pitch, making them suitable for shaft-driven generators. Fixed-pitch propellers require RPM changes that would destabilize generator frequency, while tandem and detachable-blade propellers address physical arrangement, not thrust control independent of RPM.