Similar in design to the Charlie class submarine, the Papa class is regarded as a predecessor to the Alfa class submarine and Sierra class submarine, and may have tested technologies which were later used in those classes.
The Papa class was similar in design to the Charlie class submarine. The Papa class is regarded as a predecessor to the Alfa class submarine. The Papa class is regarded as a predecessor to Sierra class submarine. The Papa class may have tested technologies. These technologies were later used in those classes.