The drone submarine model, unveiled by CSSC at the Zhuhai Airshow ... propulsion systems driving a single unshrouded stern propeller, and mission systems located in the bow.

However, this detector doesn’t use sonar. Rather, it depends on an antenna that detects low-frequency EM waves that submarine propellers generate with each rotation. When the waves make contact ...

[SUBRON stands for SUBmarine squadRON.] One submarine had been in minor overhaul alongside the pier, with her propellers removed, and in the haste to make ready, the propellers were re-installed ...