A Chinese research ship has successfully tested a new electro-hydrostatic actuator capable of slicing undersea cables at depths up to 3,500 meters. The trial, conducted aboard the Haiyang Dizhi 2, bridges the gap from development to practical application, according to official reports. The demonstration coincides with heightened concerns over sabotage of global submarine cables.
The Haiyang Dizhi 2, equipped with a 150-ton crane and a 10-kilometer fiber optic winch, carried out the sea trial during a deep-sea science expedition. China Science Daily, published by the Chinese Academy of Sciences, reported that the test reached 11,483 feet (3,500 meters) and addressed the 'last mile' in deep-sea equipment deployment. The device, designed by researchers at the China Ship Scientific Research Center and the State Key Laboratory of Deep-sea Manned Vehicles, uses a diamond-coated grinding wheel powered by a compact electro-hydrostatic actuator to cut through armored cables. Its maximum depth capability is 13,123 feet (4,000 meters), and it fits on remotely operated vehicles, as detailed in South China Morning Post reporting from a 2025 journal publication in Mechanical Engineer. The technology is described for civilian 'marine resource development,' though previous patents have come from People's Liberation Army organizations and universities like Lishui University. Analyst Wendy Chang of the Mercator Institute for China Studies called it a 'show of strength,' noting China's mixed signals on subsea infrastructure amid denials of involvement in incidents like anchor damage by its ships. Chinese-flagged vessels have damaged cables and pipelines in the Baltic Sea in October 2023 and November 2024, which officials called accidents. Similar capabilities exist with the US and Russia, including Cold War-era submarine operations. Concerns persist over vulnerabilities in the 1.5 million kilometers of global submarine cables, especially near Taiwan and Guam.
