(WSJ) For decades, the United States didn’t have to worry much about China’s submarines. They were noisy and easy to track. Meanwhile, the Chinese military struggled to detect the ultra-quiet submarines of the US.
Now, China is closing one of the significant gaps between the US and Chinese militaries as it advances its submarine technology and underwater detection capabilities, which carries significant implications for US military planning regarding a potential conflict over Taiwan.
Earlier this year, satellite images revealed that China deployed a nuclear-powered attack submarine with a jet propulsion system instead of a propeller. This marked the first instance where noise reduction technology, similar to that used in the latest American submarines, had been observed in a Chinese submarine.
A few months prior, satellite images of the Chinese nuclear submarine production base in the northeastern city of Huludao displayed hull sections laid out in the facility that surpassed the size of any existing Chinese submarine hull.
The completion of a second modern construction hall at the factory in 2021 indicates plans for increased production.
Simultaneously, the western Pacific has become more perilous for US submarines. Beijing has constructed or nearly finished several underwater sensor networks, known as the “Great Underwater Wall,” in the South China Sea and other regions along the Chinese coast.
These networks significantly enhance the ability to detect enemy submarines, according to Chinese military and academic sources.
The People’s Liberation Army, known as China’s military, is improving its capacity to locate enemy submarines by incorporating patrol aircraft and helicopters that gather sonar information from buoys at sea.
The majority of the Chinese navy now possesses the capability to install underwater listening devices called hydrophones on cables that accompany ships or submarines.
In August, China conducted a submarine-hunting exercise lasting over 40 hours in the South China Sea, involving dozens of Y-8 anti-submarine patrol aircraft. A few weeks earlier, the Chinese and Russian navies conducted a joint anti-submarine warfare exercise in the Bering Sea, off the coast of Alaska.
The developments mean that the era of unchallenged US dominance in the seas around China is coming to an end.
In recent years, China has also rapidly expanded its surface fleet. It now exceeds the US fleet in number of ships, although China’s ships are generally smaller and less sophisticated.
In response, a larger percentage of the US Navy has been deployed to the Pacific, including some of America’s most advanced ships and aircraft.
The US has also increased the pace of naval operations in the region and deepened coordination and training with allied fleets, such as Japan.
The US also needs new strategies below the waves to face a more potent adversary, said Christopher Carlson, a former US Navy officer.
The US needs far more resources, such as patrol aircraft and attack submarines, to locate, track and potentially target a new generation of quieter Chinese submarines, he said.
“The implications for the US and our Pacific allies will be profound,” he said.
Simulations of a Chinese invasion of Taiwan conducted by US military analysts often assume that US submarines would attempt to sink the ships of the attacking Chinese fleet.
Destroying Chinese ships could help mitigate the invasion and allow Taiwan to better defend itself, some of the simulations show, but a greater threat to US submarines would complicate this task.
Even getting close to the Taiwan Strait could become more precarious. China’s nuclear-powered attack submarines could be given a hunter-killer role, seeking out U.S. and allied submarines off eastern Taiwan, said Brent Sadler, a former U.S. submarine officer who is now a senior fellow at the Heritage Foundation. a public policy research and analysis organization (think tank) based in Washington, DC.
Hard to hunt
An indication of the growing risks in countering China’s submarine fleet came in March, when General Anthony Cotton, head of the US Strategic Command, said during a congressional hearing that China had installed new missiles on its submarines with ballistic missiles that could hit targets inland. the US while remaining close to China.
Tracking these Chinese submarines is one of the main functions of the US Navy and its attack submarines in the Asia-Pacific region.
A book published by a former PLA officer in 2020 suggests that the new Chinese attack submarines will have their engines mounted on shock-absorbing rafts to better dampen vibrations.
China is working on other silencing technologies for submarines, such as new hull materials and more efficient nuclear reactors for propulsion, academic research shows.
Based on the information available, Carlson, the former US Navy officer, predicts that the new Chinese submarines will be as quiet as the Russian Akula I-class attack submarines commissioned in the 1990s – a series still in service today that marked a leap forward in stealth and technology speed of previous Russian submarines.
“Finding such a quiet boat is going to be very difficult,” he said.
Much of China’s current submarine technology comes from reverse-engineered diesel-electric submarines bought from Russia after the collapse of the Soviet Union. Closer military ties between Moscow and Beijing following Russia’s invasion of Ukraine have raised concerns that Russia may be willing to share some of its advanced submarine technology with China, but there have been no clear indications of such transfers.
It is true that a new generation of Chinese nuclear-powered submarines is years away from active service and significant progress in the program is not guaranteed. Submarines often go through several prototype stages over a period of years before final designs are achieved.
The new attack submarine launched by China this year may be a test model that is not intended for deployment. Entire projects can be canceled for technical, economic or political reasons. The US Seawolf class submarine program was abandoned in 1995 due to high costs.
There is also little chance that China will soon catch up with the US in submarine technology. The latest US Virginia-class attack submarines and the planned Columbia-class ballistic missile submarines are a generation ahead of China’s capabilities in terms of noise reduction technology, propulsion, weapons systems and other areas, military analysts say.
But China doesn’t necessarily need to match US capabilities. By manufacturing submarines that are much harder to detect and producing them on a large scale, it can increase the resources used by the US military to monitor them. And any war would probably be fought in China’s backyard, the area it knows best.
To patrol the region, the US rotates squadrons of P-8 aircraft through a base in Okinawa, Japan. A recently retired US anti-submarine warfare officer said that the lack of US anti-submarine patrol aircraft permanently based in the Asia-Pacific region would be a disadvantage.
“We know where their replacements are now,” he said. “But continuing to do so depends on having the resources to control them.”
China’s “Great Underwater Wall”
In 2017, the Chinese government approved plans to build sensor networks over five years in the South China Sea and the East China Sea, where Taiwan is located, to monitor the regions in real time.
China’s underwater sensor networks echo the Sound Surveillance System, or Sosus, developed by the US during the Cold War to detect Soviet nuclear submarines through a network of hydrophones fixed to the seabed.
A few years ago, China also placed listening devices on the seabed near the island of Guam, where an important US submarine base is located.
The growth of Chinese underwater sensor networks means that US submarines can no longer rely solely on their stealth capabilities to avoid detection in the South China Sea and other areas close to the Chinese mainland, said Bryan Clark, a former Navy officer who is now a senior research fellow at the Hudson Institute, a Washington, DC-based think tank.
Clark said the US needs a new strategy to confuse or suppress China’s underwater sensors by deploying unmanned submersible craft that can jam surveillance systems, act as decoys or destroy sensors.
China is under pressure to improve its sub-hunting capabilities, while the US is working with allies to increase its submarine advantage. In 2021, the US and the UK said they would help Australia build its first nuclear-powered submarines.
Australia’s new submarines are not expected to be deployed until the 2040s, so as an interim measure, the US agreed this year to sell up to five US Virginia-class nuclear-powered attack submarines to Australia in the 2030s.
The US also pledged to rotate attack submarines through a base in Western Australia by 2027 to help its military gain proficiency in maintaining nuclear submarines.
A Chinese government spokesman said in March that plans to increase Australia’s capabilities would lead “down the path of error and danger”.
US lagging behind
China’s recent advances have also highlighted a shortfall the US faces in its own submarine fleet. The Navy has begun moving more submarines to the Asia-Pacific region and says it needs 66 nuclear-powered attack submarines to fulfill global missions.
The US has 67 nuclear-powered submarines, but only 49 of them are attack submarines, the result of a decline in construction after the end of the Cold War.
Its attack submarine fleet is expected to shrink to 46 boats by 2030, as older submarines are retired, before recovering to 50 by 2036, if an annual construction rate of two submarines can be achieved, up from the current rate of 1.2. In the Navy’s most optimistic scenario, it would have 66 attack submarines by 2049.
China currently has six nuclear-powered attack submarines. Carlson, the former US Navy officer, predicts that once China settles on new designs, it could triple the current US annual production rate.
In its annual assessment of the Chinese military published this month, the Pentagon predicted that China would have a total fleet of 80 attack and ballistic missile submarines by 2035, up from 60 at the end of last year.
China’s main base for nuclear-powered submarines is on the southern island of Hainan. To accommodate more submarines, China added two new piers to the base this year, in addition to the four existing piers. Two submarines can dock at each pier.
Hainan lies at the northern end of the South China Sea, a maritime region where China has built military bases on artificial islands and has some of its most extensive surveillance systems, both above and below the surface of the sea.
Sadler, the former US submarine officer, said China’s development of more advanced submarines has increased the likelihood of a military confrontation with the US this decade.
“Regardless, the US submarine force will certainly be more in demand than ever throughout the Pacific,” he said, “and with increasingly narrow margins of advantage over its principal adversary.”