China claims to test experimental magnetic engine that can make submarines more silent

China has built and tested its first-ever permanent magnetohydrodynamic (MHD) or magnetic propulsion engine for its naval vessels. It can also be used to power submarines, making them silent and hard to detect, almost like the one described in the novel "Hunt for Red October".

The system makes use of powerful magnetic fields to propel itself forward in the water. A report in Popular Mechanics mentions that while the technology is not new, it is has so far been considered impractical. This is the first time the Chinese have built a full-scale working version.

This MHD engine-powered vessel was tested in the South China Sea near the Hainan islands, the country's southern-most point. The ship was docked at a base in Sanya and during tests, and reportedly reached the "designated" speed.

MHD engines work by pumping seawater through an underwater shaft, past a metal rim, moving the system forward. The propulsion system uses superconducting magnets to form strong fields, which force electrified water through the shaft. Since there are theoretically no moving parts, a ship, or any vessel using this technology would be quite silent. To quote the submarine captain from the popular novel, "Once the world trembled at the sound of our rockets ... now they will tremble again—at the sound of our silence."

According to a report on MHDs by American Association of Physics Teachers, the only real, working prototype was tested by Japan in 1992.

The official military site of China reported that The State-owned China Shipbuilding Industry Corporation (CSIC) has sent out a message on their official WeChat public profile to confirm that the test had been conducted.

There was no mention made of the type of vessel, its size, the actual speed it attained, the size of engine, or its capacity. The report did say that the motor was made with Chinese submarines in mind, to significantly reduce their operating sound to the lowest possible levels.

This Chinese motor is made through patents that the CSIC holds, reports the ChinaMilitary website.

"The new high-performance permanent magnet motors made from rare-earth materials avoid the flaws of traditional motors that work under the excitation principle, and can provide much greater power density, and can significantly reduce its working noise," Song Zhongping, a military analyst.

The report also said that this technology is ahead of the American one and that it is suitable for high speed nuclear submarines.