Submarine detection system

From Wiki China org cn

China's trial operation of the submarine detection system was successfully finished on October 7, 1995. It enabled China to detect 97 percent of the ocean (trench excluded), and provided advanced techniques for China's exploration of polymetallic nodules on the ocean floor.

To build up such a system, problems related to high-pressure sealing, signal collection, autonomous navigation control and a power system had to be tackled.