Chinese researchers have reportedly made significant progress in developing a new submarine detection system, which could reduce the effectiveness of stealth technology in modern naval warfare. The technology does not rely on traditional sonar but instead captures low-frequency electromagnetic (EM) waves generated by a submarine’s propellers.
Scientists from Shanghai Jiao Tong University reportedly tested this system in the South China Sea, where they claim it successfully detected signals that would otherwise go unnoticed using conventional methods.
Unlike sound waves, which weaken quickly in seawater, EM waves penetrate the seabed and travel farther, allowing for detection over greater distances. The detection device, described as being similar in size to a pickup truck, reportedly identified faint signals from submerged vessels during deep-sea trials. If fully developed, the method could hypothetically challenge the stealth capabilities of advanced submarines, including those used by the United States and its allies, according to the South China Morning Post.
In addition to electromagnetic tracking, Chinese scientists have allegedly explored another approach that focuses on magnetic wake signatures, disturbances left behind as a submarine moves through the ocean.
Research conducted at Northwestern Polytechnical University (NPU) in Xian analyzed how submarines create subtle interactions with Earth’s magnetic field. Their findings suggest that even the most advanced submarines generate detectable magnetic disturbances, making it possible to identify their presence despite efforts to remain hidden.
By studying the Kelvin wake, a distinctive wave pattern produced by submarines as they cut through the water, researchers determined that several factors influence the strength of a vessel’s magnetic signature. A slight increase in speed can amplify the magnetic intensity tenfold, while reducing the submarine’s depth by just a few meters can double the signal’s strength.
One of the primary concerns raised by this research is the potential impact on the U.S. Seawolf-class submarines, which are considered among the most advanced in stealth technology. These submarines were designed to operate undetected by using anechoic tiles to absorb sonar waves and shock-absorbing floating raft systems to minimize onboard noise. Additionally, their deep-diving capabilities, reaching depths of approximately 600 meters, make them more difficult to track using conventional methods.
However, the latest Chinese research suggests that these submarines may no longer be as invisible as previously believed. If magnetic wake tracking and EM wave detection are successfully integrated into operational systems, Seawolf-class submarines could be at greater risk of detection in contested waters such as the South China Sea and the Taiwan Strait.
Previous attempts to track submarines using electromagnetic signals had a limited range of just over 1.5 miles. However, Chinese researchers claim that recent technological advancements could extend this detection range beyond 31 miles. Chinese Scientists proposed deploying a network of high-precision sensors across a wide area to track subtle submarine signals. These sensors would need to be synchronized with extreme precision—within a billionth of a second—to ensure accurate data collection.
