China has, of course, denied that the incident ever took place, but about 55 Chinese sailors aboard a submarine number 093-417 are believed to have died in an accident in the Yellow Sea off China’s Shandong province. British intelligence reports that the submariners died on August 21, 2023 after a “catastrophic” failure of the ship’s oxygen systems.
“It is our understanding that the death was caused by hypoxia due to a system failure on the submarine. “The submarine encountered a chain and anchor obstacle that was used by the Chinese People’s Liberation Army Navy to capture U.S. and allied submarines,” the report said. “This resulted in system failures that took six hours to repair and surface the ship. The onboard oxygen system poisoned the crew after a catastrophic failure.”
Since the report is based on intelligence information, the United Kingdom has refused to comment on the veracity of the reports, while Beijing maintains that the incident was a rumor. If the submarine actually ran into its own chain and anchor halyard and its batteries were weak, the air purifiers and air treatment systems would probably fail at some point.
While U.S. and British submarines have equipment that can convert carbon dioxide into oxygen, allowing them to remain submerged for extended periods of time, not every country has access to the same technology. The “chain and anchor” is a device designed to trap and destroy enemy ships underwater. The idea is simple: A heavy chain of metal balls and other objects (which can be up to several miles long) is attached to two anchors attached to the seabed.
The size and weight of the chain can cause severe damage to a ship’s rudder and propeller and delay the submarine for hours or even days, which, as we can see from the PLA Navy’s alleged incident, is detrimental to the ship and its crew can be fatal. The submarine can even be pulled to the seabed using the trap.
Such chain and anchor traps are used to protect strategic or sensitive positions such as ports, harbors or shipping routes. The British intelligence document suggests that this particular trap was intended to catch American or British spy submarines operating off the Chinese coast. Shandong is a multi-city province with a population of more than 9 million, roughly the size of New York City. Qingdao is the largest city in the province with 10 million inhabitants.
While much of the world’s attention is focused on Chinese naval operations in the South China Sea, particularly in the waterways between Taiwan and mainland China, the Yellow Sea is also a strategically important body of water along China’s coast. The country shares maritime borders with North Korea, South Korea and Japan in these waters and is an important location for commercial fishing, oil and gas exploration and commercial trade. The Yellow Sea is also a key supply route between China and Russia, which supplies the People’s Republic with nuclear material used to make nuclear warheads.
The loss of 093-417 is a big deal for the People’s Liberation Army Navy. It is one of the more advanced submarines in its fleet, as it runs quieter and has more advanced armament (including anti-ship missiles and new, advanced torpedoes).
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