China needs to defend itself from hostile submarines. Its goals of gaining regional power while protecting the mainland require a maritime strategy in the Western Pacific, especially in the areas Chinese military planners call the two island chains. The first island chain encircles the Yellow Sea, East China Sea and South China Sea. The second stretches from Japan to Indonesia. Beijing thus needs to develop robust anti-submarine warfare capabilities to keep submarines out of the first island chain, where many mainland and naval targets would be in range of attack.
The People's Liberation Army Navy, however, does not have the means to counter U.S. submarines — the critical threat — or even those of nearby powers, including Japan and South Korea. Consequently, Beijing is devoting considerable resources to enhance the navy's anti-submarine warfare capabilities and correct one of its greatest military weaknesses. China's navy will improve, but it is still many years of effort and investment away from achieving the level of capability Beijing requires.
At the moment, the People's Liberation Army Navy does not have the equipment, training and institutional knowledge necessary to effectively counter most submarine threats. Until recently, for example, the military relied on Type 037 submarine chasers, armed only with hull sonar and anti-submarine warfare rockets, mortars and depth charges. These are only adequate in certain cases against shallow diving submarines or in littoral water. They are largely ineffective against fast and deep diving nuclear submarines. With effort and investment, Beijing has begun to adopt more advanced patrol craft, such as the Type 056A corvettes in 2014. China's nuclear submarines, however, still lag behind, not quiet effective enough to hunt submarines, and certainly not able to challenge more advanced U.S. nuclear submarines.
Although Beijing began developing anti-submarine torpedoes in the 1980s, the navy did not have dedicated anti-submarine warships to carry them. The military also had inadequate numbers of anti-submarine helicopters — mostly lightweight Z-9Cs and somewhat more capable Ka-28 types. Until recently, the shortage of helicopters forced the navy to rotate them between ships. Instead of state-of-the-art equipment, China continued to rely on outmoded means such as naval mines to hinder submarine operations. Beijing even planned to string these mines across chokepoints and deploy them close to enemy harbors to hinder unfriendly surface and submarine vessels alike, though the tactic never needed to be implemented.
At the beginning of the 21st century, Chinese anti-submarine capabilities began to improve. The navy's multi-role surface vessels were equipped with variable depth sonar, anti-submarine torpedoes and greater numbers of helicopters. But it was not until the rollout of the Type 052C destroyer in 2005 that any Chinese vessel was equipped with a towed sonar array. China also continued to lack dedicated anti-submarine patrol aircraft, with only a few aging Harbin SH-5s in service.
Now China's anti-submarine warfare requirements are growing as the People's Liberation Army Navy steps up operations in the South and East China Seas. Beijing's dearth of vessels, patrol aircraft, helicopters and equipment means that anti-submarine warfare coverage is not always available. When it is, it is not sufficiently advanced or capable. While China could adequately clash with weaker powers such as Vietnam or Taiwan, the navy lacks the means to operate in the deep waters of the open ocean, also known as blue water capabilities. It could not counter U.S. nuclear submarines or even sophisticated diesel electric submarines such as Japan's, which have had training against an extensive array of modern, effective anti-submarine capabilities.
Chinese military strategy includes preventing foreign military intervention. China has developed anti-air and anti-surface capabilities to support this strategy. However, its anti-submarine capabilities are still unable to chase away or destroy advanced submarines, such as those from the United States. Torpedoes equipped on U.S. multi-role submarines threaten Chinese surface action and amphibious landing groups while cruise missile could reach onshore targets. To remedy this critical weakness, Beijing is building up its navy to deter or hamper any U.S. intervention on behalf of Pacific allies. But while the effort has advanced air and anti-ship defenses, China still cannot yet counter U.S. nuclear submarines.
The days when Beijing relied on naval mines and depth charges for defense are coming to an end.
And U.S. submarines are not the only threat to Chinese security. South Korea, Japan, Malaysia and Vietnam are developing or fielding large numbers of advanced diesel electric submarines, a number of which are air independent propulsion models able to remain submerged for longer periods. Even Taiwan, a principle focus of Chinese war planning, is determined to build up its submarine fleet. With these improvements, China now must contend with multiple submarine threats in most potential conflicts, making anti-submarine capabilities crucial.
Beyond potential clashes in the Western Pacific, anti-submarine warfare is essential to China maintaining credible nuclear deterrence. Nuclear attack submarines, in this case from the United States, are the principle weapon charged with locating and destroying Russian and Chinese nuclear ballistic missile submarines. Maintaining a vigorous anti-submarine screen is vital around harbors, chokepoints and operating areas, ensuring that the sea leg of China's nuclear triad remains intact.
Beijing is aware of the need to enhance its anti-submarine warfare. With its rapid economic growth, it is now has technology and finances to invest in developing these capabilities. It is already using these resources to close the gap with its neighbors and the United States. Anti-submarine warfare, however, is complex — equal parts art and science. It will take China years if not decades to become highly proficient in the craft. Moreover, the skillset is highly perishable. U.S. Navy personnel even attest to how anti-submarine capabilities wane while the military focuses on other missions.
But Beijing is off to a good start. China has added Gaoxin-6 anti-submarine airplanes to the North Sea Fleet. These aircraft carry sea-search radar, a large magnetic anomaly detector boom and other anti-submarine equipment and weapons. They are broadly comparable to the U.S. P-3 Orion aircraft — the anti-submarine workhorse for many militaries worldwide.
Beijing is also ramping up production of anti-submarine corvettes and equipping their surface vessels with advanced detection equipment in the form of active variable depth sonar and passive towed sonar arrays. They are adding acoustic decoys and providing these vessels with rocket-assisted homing torpedoes. The Chinese have also been conducting extensive surveys and mapping of operating areas such as the South China Sea, and are building a network of underwater sensors to detect submarines across the South and East China Seas. On top of this, the military is experimenting with unmanned underwater vehicles with anti-submarine warfare applications. Most important, Chinese sailors, aircrew and technicians are consistently training to improve their skills.
China is rapidly improving their anti-submarine warfare skills. The days when Beijing relied on naval mines and depth charges for defense are coming to an end. Still, the gap between Beijing's current anti-submarine warfare capability and U.S. and Japanese submarines is large enough to pose a serious threat to Chinese naval strategy for many years to come.