As China’s naval power surges into the 21st century, its submarine fleet has become a symbol of quiet strength beneath the surface. The People’s Liberation Army Navy (PLAN) is rapidly modernizing, expanding both its diesel-electric and nuclear-powered submarine fleets to stake its claim in contested maritime regions like the South China Sea and the East China Sea. But amid this modernization, the haunting memory of submarine disasters, especially the Ming-class 361 tragedy, still echoes through the PLAN’s ranks.
The tragedy of submarine 361 remains the deadliest peacetime accident in Chinese naval history. More than two decades after the April 2003 incident, it continues to shape China’s approach to submarine operations and underscores the deadly risks that come with commanding the deep.
As of August 2024, China’s submarine fleet numbered around 60 vessels. Analysts expect this figure to rise to at least 65 by the end of 2025, with predictions that China could double its fleet by 2035. Scholars who track PLAN developments say the country may be commissioning 1.5 nuclear-powered submarines per year—an impressive rate rivaled only by the U.S. and Russia.
What makes this expansion so strategically significant is the fact that submarines, unlike most military assets, cannot be tracked from space. This allows Beijing to project power, intimidate rivals, and operate in contested waters while retaining plausible deniability.
Recently, satellite images posted on Google Maps revealed a cluster of six nuclear-powered submarines docked at China’s ‘First Submarine Base’ on the Yellow Sea. These included two Type 091 submarines and two Type 093A attack submarines. The location, positioned close to the East China Sea and Sea of Japan, is vital for Chinese rapid-response capabilities.
Despite technological leaps, China’s undersea program is not without its setbacks. In 2023, reports emerged of a Chinese submarine accident in the Taiwan Strait. Though Beijing denied the incident, a U.K. intelligence report later cited by the Daily Mail claimed that a Chinese vessel struck a “chain and anchor” trap off Shandong province—likely a passive deterrent set up by Western navies. The report alleged that 55 crew members died, though China never confirmed the details.
Even more recently, China’s newest Zhou-class nuclear submarine reportedly sank while docked at the Wuchang shipyard near Wuhan during construction. While damage assessments remain classified, the setback raises questions about safety protocols in China’s rush to modernize.
Yet none of these incidents compare in scale or symbolism to the tragedy of the Ming-class 361 submarine.
On April 25, 2003, a Chinese fishing vessel spotted a periscope drifting aimlessly off the country’s northeast coast. Alarmed, they contacted authorities. PLAN dispatched two ships to investigate. Fearing an intrusion by a foreign vessel, perhaps Japanese or South Korean, they prepared for confrontation.
What they found instead was their own submarine—Ming-class 361—completely unresponsive.
The diesel-electric sub had vanished from radar days earlier during military exercises in the Yellow Sea. When PLAN forces finally boarded the vessel on April 26, they made a chilling discovery: all 70 crew members were dead.
The submarine had been on a silent operation, maintaining radio blackout as part of the drill. Ironically, that very discipline delayed any rescue attempt for over a week, allowing a fatal malfunction to go unnoticed until it was far too late.
China initially kept the tragedy quiet. Only after the crew had been recovered and buried did then-President Jiang Zemin acknowledge the disaster, citing “mechanical failure” without elaboration.
Military analysts and independent experts have since pieced together likely scenarios. The Ming-class submarines were designed to accommodate no more than 57 crew, yet 70 personnel were aboard 361. This overcrowding, observers say, may indicate that the vessel was conducting special tests, possibly involving a prototype Air Independent Propulsion (AIP) system.
Another theory, cited by Wen Wei Po, suggests the diesel engine may have run while the sub was snorkeling just below the surface. When the air intake valve malfunctioned—either due to high water or a faulty sensor—the engine continued to burn through the oxygen onboard, creating a vacuum.
If accurate, this would have meant the submarine’s air supply was depleted within two minutes, leaving the crew disoriented, unconscious, and ultimately dead.
A Hong Kong-based report explained that the snorkel, designed to prevent water from flooding the diesel engine, may have closed automatically during rough seas. If the engine failed to shut down when the valve closed, it would have quickly consumed all breathable air onboard.
The PLA Navy reacted to the 361 tragedy with rare public displays of accountability. Admiral Shi Yunsheng, then commander of the PLAN, and Political Commissar Yang Huaiqing were both dismissed from service. This marked a significant move for the Chinese military, where top officials are seldom held responsible so publicly for operational failures.
The submarine was eventually towed to port, but China never disclosed the specifics of the recovery operation. Nor were photos or detailed descriptions of the interior damage released. Nonetheless, the loss of so many sailors, including high-ranking officers, triggered an internal reckoning.
Though the PLAN never released a full report, international experts believe the incident pushed China to accelerate its move toward modernizing its diesel and nuclear submarine fleets.
Following the 361 disaster, China began integrating more advanced safety features into its newer submarines. The Type 093A, for instance, includes enhanced life-support systems, improved snorkeling sensors, and escape hatches not available in the older Ming-class vessels.
The tragedy also highlighted a broader strategic need: the importance of submarine survivability and crew safety, especially during peacetime operations.
Modern Chinese submarines now undergo more rigorous trials and maintenance schedules. Furthermore, their crews receive enhanced training not just in combat, but in emergency protocol and life support procedures.
Yet with more submarines entering the fleet each year, and with increasingly complex missions in contested waters, the margin for error remains thin.
China’s undersea ambitions are as strategic as they are symbolic. Submarines, by their nature, embody stealth, strength, and endurance. They can lurk undetected for months, project power across oceans, and carry payloads—from cruise missiles to nuclear warheads—that alter the balance of global power.
The PLAN’s current trajectory suggests an underwater force capable of rivalling that of the United States and Russia within the next decade. But as the 361 tragedy shows, power without caution invites catastrophe.
While Beijing celebrates its new submarine launches, the lessons of past losses must remain present. The silence of the deep is deceptive. Underwater dominance is not just about hardware—it’s about human lives, institutional discipline, and operational transparency.
