A quantum submarine sensor has limited range, seeing several thousand meters at best. This technology is being considered for use on cheap drones.

The plan is to crowd certain straits with these drones, which are crucial for China's use. Further details about this strategy are available from the source.

Information about the implementation and potential impact of this plan is limited, but the source provides more context about the use of quantum submarine sensors on drones and the strategic importance of the straits.