Could China’s fresh electrical wake detection technology bring an end to stealthy submarine combat? It may, according to recent Chinese study.
Researchers at Northwestern Polytechnical University ( NPU) in Xian, China, have developed a novel detection method that can track even the most elusive submarines ‘ magnetic wakes, according to South China Morning Post (SCMP ) reporting this month.
The group, led by Associate Professor Wang Honglei, discovered that the electromagnetic fields generated by the wake of ships, such as the US Seawolf-class, may be detected using flying magnetometers. Exploits the electrical interactions between water ions that are impacted by the motion of the submarine and the Earth’s magnetic field.
According to the study, which was published in Harbin Engineering University’s Journal in December of last year, underwater dimensions, depth, and accelerate all affect the intensity of these magnetic signatures. Electrical wakes cannot be silenced and leave a continual trace, unlike traditional acoustic detection techniques.
The USS Connecticut’s wiring in the South China Sea in 2021, which among other items highlighted the growing difficulties of cunning operations in contested waters, is the focus of the Chinese study. Underwater naval battle may experience a revolutionary shift as China incorporates electromagnetic monitoring into its wider “kill web” of detection technologies.
The rapid evolution of underwater detection technologies poses a threat to submarines ‘ standard stealth and tactical utility, which could require changes in underwater design, countermeasures, and operational strategies to keep their relevance in upcoming issues.
Traditional radar systems are less effective in deep water, like the Taiwan Strait, while new monitoring capabilities and limitations, such as those from Magnetic Anomaly Detection ( MAD), are introduced.
In shallow lakes as thin as the Taiwan Strait, which is only 150 meters deep, magnetic detection has a number of advantages over radar. Low-frequency radar success is reduced by deep depths, according to Bo Raskin of the Naval Submarine League, which causes good directing, where energy is absorbed by the ground and exterior reflections.
He adds that towed radar arrays have trouble detecting small targets and selection because longer wavelengths of low-frequency good struggle to spread in shallow water and because wet seafloor clutter and powerful bottom reverberation prevent detection.
But, Rajiv Sithiravel and other authors make mention of an aerial Wild with a non-linear trouble in an October 2020 article in the peer-reviewed Ia Transactions on Aerospace and Electronic Systems book, which is complicated by the complex relationship between a ship’s magnetic name and motion, which makes it difficult to perform accurate tracking and estimation.
Sithiravel and others claim that without additional maneuvers, such as curved flight paths, MAD cannot determine whether a detected anomaly is to the left or right of the aircraft’s flight path due to the left or right positional ambiguity. In addition, they note that MAD’s short detection range makes it more suitable for short-range confirmation rather than long-range detection.
Advancements in stealth tactics and techniques can keep submarines relevant in upcoming conflicts despite the threat posed by MAD and other sensor technologies.
A January 2025 article by the Australian Naval Institute says submarines use anechoic tiles, vibration-damping materials, radar-absorbing materials and periodic degaussing to enhance stealth. Additionally, the article mentions how submariners use methods like using uncrewed underwater vehicles ( UUVs ) to evade detection and noise manipulation.
However, Roger Bradbury and other authors make mention of this in a March 2023 article for The Conversation that advancements in sensor technology, underwater communications, and artificial intelligence ( AI ) may have the potential to make submarines both detectable and obsolete by the 2050s.
According to Bradbury and others, these new technologies can detect subtle changes in the ocean’s physical, chemical, and biological markers as well as changes in the Earth’s magnetic field, which could compromise their stealth and significance in upcoming conflicts.
The US Navy must adapt its submarine design and operational strategies to counteract the growing need for multi-layered detection systems that combine advanced technologies.
Combining airborne MAD with other technologies, such as magnetic wake detection, terahertz-based devices, airborne extremely low-frequency ( ELF ) radar, and light detection and ranging ( LIDAR ) satellites, can create a multi-layered detection grid to track US and allied submarines in near real-time.
These advancements have the potential to have a significant impact on US submarine operations and design. In a March 2018 article for Georgetown Security Studies Review, Ryan Neuhard asserts that the US Navy’s submarine force must work through a variety of strategies to adapt to changing detection technologies.
Neuhard suggests that upcoming submarine designs should use propulsion, hull design, and magnetic cloaking innovations to improve stealth capabilities in favor of minimizing sound, magnetic, and wake disturbances in order to evade advanced detection systems.
He adds that the US can enhance the security and effectiveness of its submarines by implementing defensive measures like jammers and unmanned vehicles while also transitioning them to function as autonomous systems ‘ command centers.
The South China Sea’s underwater surveillance system poses significant challenges and threats to US submarine operations, as well as having important strategic implications for regional security and nuclear deterrence.
China’s new submarine detection technologies, which offer secure nuclear second-strike capability, can help secure the South China Sea as a protected bastion for its nuclear ballistic missile submarines ( SSBN).
Dolma Tsering claims that China has constructed an” Underwater Great Wall” ( UGW), a comprehensive underwater sensor network in the South China Sea that combines sensors, sonar, unmanned underwater vehicles, and surface ships to track both surface and underwater activity in real-time in a report for the National Maritime Foundation in December 2016.
Tsering mentions that China’s UGW, modeled after the US Cold War-era SOSUS, improves China’s submarine detection and tracking capabilities. She points out that it directly challenges US operations and calls for a rethinking of its undersea strategy, particularly in the crucial Taiwan Strait.
Further, in a March 2024 report, the South China Sea Strategic Situation Probing Initiative (SCSPI), a Chinese think tank, mentioned that in 2023 at least 11 US nuclear attack submarines ( SSN) and two US SSBNs appeared in the South China Sea.
While the report says they aim to “exert deterrence”, the US SSNs may track China’s SSBNs in the South China Sea. Because China is most likely to respond to threats that threaten its nuclear arsenal with retaliation, such actions have a strategic impact.
The development of Chinese magnetic detection technology may well signal the end of submarine stealth. As detection capabilities evolve, future conflicts could see submarines forced to shed their traditional invisibility cloak and adopt new roles, emphasizing long-range precision strikes, drone coordination and command-and-control functions.
Submarines are supposed to adapt, but the question is whether they will remain relevant in a new era of transparency beneath the waves.