The Seawolf-class fast-attack submarine USS Connecticut departs Puget Sound Naval Shipyard in Washington state for sea trials after maintenance in December 2016. Photo: US Navy / Thiep Van Nguyen II / via Wikipedia

The US nuclear-sub accident last month demonstrated operator incompetence, government hypocrisy and the environmental threat posed by such operations in the South China Sea.

On October 7, the US Navy announced that five days earlier, on October 2, its Seawolf-class nuclear-powered and nuclear-weapons-capable submarine USS Connecticut had hit an unidentified object in the South China Sea. According to the announcement, the submarine “remained in a safe and stable condition” and its “nuclear propulsion plant and spaces were not affected and remain fully operational.” 

The vessel eventually proceeded on the surface under its own power to Guam, where the damage is being assessed.  

The US Navy’s announcement was brief and vague. It did not say what the submarine hit or where – only that it was “operating in international waters in the Indo-Pacific region.” It turned out to be a “seamount” in the South China Sea. 

The incompetence of the sub’s commanders was admitted. In removing two officers and the chief of the boat from their positions, Vice-Admiral Karl Thomas, commander of the US 7th Fleet, detailed their errors. He “determined [that] sound judgment, prudent decision-making and adherence to required procedures in navigation planning, watch team execution and risk management could have prevented the incident.” 

As a former US attack-sub commander put it, “Not everything goes right all the time,” and “even pros have bad days.” In this case they had a very bad day.

Hypocritical call for ‘transparency’

US hypocrisy was painfully apparent. The US has frequently accused China of a lack of transparency in military matters. This is a red herring. Military transparency favors the stronger players, because they can learn the weaknesses of others while intimidating them by allowing calculated glimpses of their superiority. 

In this instance the US was anything but transparent regarding the details even though the accident generated worries about radiation affecting its friends and allies in the region.

 China’s Foreign Ministry spokesman said, “The United States should clarify more details of the occurrence, including the specific location, the intention of its navigation, what kind of object the sub had struck, whether it caused a nuclear leak that would contaminate the marine environment. It’s irresponsible and displays a lack of transparency on the part of the US to deliberately delay and conceal the details of the accident.” 

The US Navy said the delay in reporting the incident was due to concerns about “keeping the damaged sub safe and ensuring a thorough investigation of the incident.” The navy refused to specify the location of the accident “due to operations security.”

But it is not clear why reporting the incident right away and its location would endanger the sub’s safety and compromise the investigation. One possibility is that the accident occurred in waters under China’s jurisdiction and the US feared that China might demand to take over or at least participate in the investigation. In other words, the sub may have been violating China’s laws and rights in its 200-nautical-mile exclusive economic zone (EEZ).

On October 3, the day after the accident, a Seawolf sub was spotted on the surface 43 miles southeast of the Paracel Islands. So the accident might well have occurred within China’s 200nm EEZ around the Paracels. 

According to the sub’s manufacturer, General Dynamics Electric Boat, the missions of the Seawolf class of submarines include “surveillance, intelligence collection and special warfare,” especially in shallow waters.

China has military installations on the Paracels. It also has a very sensitive naval base at Yunlin on Hainan where it bases its nuclear-powered and nuclear-capable submarines. These circumstances again raise questions of what the Connecticut was doing and where. 

Radiation fears

Adding to the worries, a month after the incident, the US deployed a radiation “sniffing” aircraft – a Boeing WC-135 – over the South China Sea, a relatively rare occurrence. The primary mission of such an aircraft is to collect atmospheric samples to detect nuclear radiation. But if there was no leakage of radiation from the sub, what prompted the mission? It would be in the region’s public interest for the US to disclose what it found.

The incident also raised the possibility of a catastrophic accident involving a nuclear-powered or nuclear-armed vessel that releases radiation into the environment. This is not hyperbole.

Globally, nine nuclear submarines have sunk. The Soviet Navy lost five (one of which sank twice), the Russian Navy two, and the US Navy two. These were worst-case scenarios. But non-catastrophic accidents, once rare, are becoming more frequent as the numbers of such vessels increase.

In 2003, the Los Angeles-class USS Hartford grounded entering a port in Sardinia. In January 2005 the Los Angeles-class USS San Francisco struck a seamount near the Caroline Islands that did not appear on the charts the crew was using to navigate without active sonar. The sub sustained severe damage to its forward ballast tanks and sonar dome and the vessel was almost lost.

Again in March 2009, the Hartford collided with a US amphibious dock in the Strait of Hormuz. Ironically, its motto is “Damn the torpedoes, full speed ahead.” In November 2015, an Ohio-class sub grounded as it was entering its port of King’s Bay, Georgia.

This is what the public knows. But there may have been many more near-misses.  

The worst US nuclear-submarine disasters were the April 1963 loss of the Thresher and the May 1968 loss of the Scorpion. Both sank in the North Atlantic with all hands as well as their nuclear reactors and torpedoes. 

As more nuclear subs are built and deployed, the chance of a catastrophic accident increases, including in the South China Sea. The US deployed nuclear subs there at least 11 times last year. Other countries also operate nuclear submarines in the South China Sea, including France and perhaps the UK as part of its Queen Elizabeth aircraft-carrier strike group.

India, which is now sending warships to the South China Sea, has only one nuclear-powered sub but is building more. China already has four Jin-class nuclear submarines and is hoping to acquire another four by 2030. The AUKUS agreement for the US and UK to supply nuclear-submarine technology to Australia for operations that include the South China Sea will add to the mix.  

Operating submarines is difficult and dangerous. Most subs have both active and passive sonar. Active sonar sends out acoustic pulses, or “pings.” The ping will reflect back if it hits an object, like a whale, a ship, a seamount or another submarine. But subs operating in stealth mode turn off their active sonar because the ping could give away their location.   

More problematic is that the South China Sea is a difficult operating environment for submarines. It is particularly “noisy” and has rather complex and shifting bottom topography. Much of it is shallower than 200 meters, especially the approaches to the China coast. This means subs have to operate in a narrow zone between a safe distance from the bottom but deep enough to avoid detection.

An accident that released significant radiation into the marine environment would be a nightmare for the regional countries. 

Southeast Asians rely more heavily on fish as a primary source of dietary protein and income generation than any other people in the world. Such an accident could damage the marine food supply for all the littoral countries. It would probably create an aversion to eating seafood even if it were safe.

Judging from the Fukushima disaster in Japan, although the radiation may be insignificant or rapidly decrease to safe levels, the reputational damage to the fishery would last much longer. 

Response to risky behavior needed

The South China Sea coastal countries have legitimate cause for concern. If the countries with nuclear subs continue this risky behavior in other countries’ EEZs, they may be violating the duty mandated by the UN Convention on the Law of the Sea to pay due regard to the rights and duties of coastal states such as protecting the environment and not presenting a hazard to shipping. 

Risky behavior that endangers others requires a robust response. It may even be eventually necessary for countries to establish the equivalent of Sea Defense Identification Zones (SEADIZ) for submarines. Like Air Defense Identification Zones, their function would be to serve as early warning areas.

In such zones, submarines – manned and unmanned – would be requested to identify themselves, their destination and mission. If they did not, then they would be treated as potentially hostile and closely tracked wherever they went.

Such a drastic step could be obviated by more responsible and transparent operations of nuclear submarines. However, as the Connecticut accident and its aftermath show, this is highly unlikely.

Mark Valencia

Mark J Valencia is an internationally recognized maritime policy analyst, political commentator and consultant focused on Asia. Most recently he was a visiting senior scholar at China’s National Institute for South China Sea Studies and continues to be an adjunct senior scholar with the Institute. Valencia has published some 15 books and more than 100 peer-reviewed journal articles.