Source Foreign Policy Research Institute
In August 2020, China fired what were reported to be anti-ship ballistic missiles (ASBM) into the South China Sea. The missile firings were the second time that China launched such missiles into the disputed waters. The first occurred in June 2019, when China fired six ASBMs into the area.
Whether the two missile firings were launched against mobile targets or predetermined ones at sea is unclear, but it is likely that the ASBMs involved were DF-21D medium-range or DF-26 intermediate-range ballistic missiles. And since China normally conducts its missile tests in the Bohai Sea and the fact that U.S. naval forces operated in South China Sea during the weeks prior to the missile firings, China probably conducted them to not only test its ASBM capabilities, but also to deter what it considers American meddling in its waters.
Nonetheless, missile launches alone, however successful, do not mean that China can reliably hit ships at sea with ASBMs. That is because missiles and the warheads atop them are only part of a larger kill chain. Just as a rifle and bullet need a reliable human eye to hit the intended target, China’s ASBMs and their warheads need reliable intelligence, surveillance, and reconnaissance (ISR) to hit intended targets at sea. Creating such an ISR capability is not easy. But China has been steadily assembling the components needed to develop it in the South China Sea.
The Targeting Problem
While ASBMs have come a long way since the Soviet Union pioneered (and then abandoned) them in the 1970s, how they are envisioned to work remains the same. A conventionally armed ASBM is designed to take advantage of its ballistic trajectory through the upper atmosphere to propel its warhead (or warheads) to hypersonic speeds so that they can penetrate any shipboard anti-ballistic missile (ABM) system that its targets have fielded. Traveling at several times the speed of sound, an ASBM’s warhead would clearly give a defending ABM system little time to react.
Given a warhead’s mass and the speed of its descent, even a successful interception with an ABM missile might not be enough to stop it. Making matters worse for the defender, China has sought to design maneuverable warheads that would further complicate the task of ABM systems.
All that, however, assumes that China’s ISR collection assets can detect, identify, track, and target ships at sea with sufficient accuracy so that its ASBMs can locate and hit their targets. That is not a trivial matter, not least because the waters of the South China Sea contain some of the busiest maritime traffic in the world.
Just as problematic is that ships at sea tend to be constantly in motion. In 10 minutes, even cruise ships can traverse 10 km (at about 30 knots). Plus, they can change course (perhaps more than once) or stop entirely. Though a maneuvering warhead might be able to adjust its course in-flight to reduce the need for absolute ISR accuracy, there is a physical limit to how much steering ASBM warheads can do while traveling at hypersonic speeds.
Of course, China’s rocket forces could try to mitigate any targeting error by launching a salvo of several missiles and warheads against a single target. They could also employ a mix of warheads with different terminal seekers to improve the chances that one sort or another could overcome shipboard defenses. Blanketing an area with such warheads would no doubt raise the likelihood of hitting a ship at sea.
But doing so could also increase the risk of hitting other nearby ships, including neutral ones, especially if the plasma sheaths which form around warheads as they descend through the atmosphere blind their seekers. In any case, repeatedly launching ASBM salvos would deplete China’s supply of missiles far faster than launching a small number of well-aimed ones. Hence, a robust ISR capability will always play an important part in any effective ASBM system.
Fusion for Precision
China has greatly expanded its seaward-looking ISR with an array of air, land, sea, and space-based collection assets. Chinese commanders now have more ways to detect, identify, track, and target ships offshore than ever before. Paradoxically, however, the great diversity of collection assets may make it more difficult for those commanders to fuse the data from them into a single common operating picture. Creating the infrastructure needed to deconflict multiple data feeds and present information in a manner that allows commanders to make quick decisions is a major technical challenge. But given enough financial investment, China can be expected to eventually surmount it.
What might present a bigger challenge to China’s ISR fusion is an organizational one. First, it takes repeated practice (and consequently time) to iron out the kinks. The United States took decades to properly fuse its joint ISR resources after it created its unified combatant commands; on the other hand, China only reorganized its military regions into unified “theater commands” in 2017. Second, for fused ISR data to be of any use, it must be coupled with the centralized authority to act, but that runs against Beijing’s traditional preference to disperse authority in its military to ensure its subservience to the Chinese Communist Party (CCP).
Exemplifying that, for over 70 years, the Chinese military has operated under a dual-command system, where decision-making is shared between line officers and political commissars. While three decades of reform has transformed China’s military into a far more professional fighting force, Chinese General Secretary Xi Jinping’s drive to root out any hint of dissent (even among top CCP leaders) shows how easily it could backslide.
Missiles and Seekers
Should China overcome the challenges to fusing (and using) its ISR data, the South China Sea is likely to be the first maritime area where Chinese commanders have sufficient ISR fidelity to support ASBM targeting. As for the ASBMs themselves, the missiles most commonly thought to have an anti-ship role are the DF-21D and DF-26. The DF-21D is said to have a range of 1,500 km and the DF-26 a range of 4,000 km. From their launch sites on the Chinese mainland, the DF-21D could cover most of the South China Sea as well as the approaches to it from the Pacific Ocean through the Bashi and Luzon Straits. The DF-26 could cover not only the South China Sea but also large parts of the Indian and Pacific Oceans and beyond.
But the longer an ASBM’s range is, the more accurate the ISR data must be to target a ship at sea because greater distance would give the ship more opportunity to get out of harm’s way. Thus, China has fitted its DF-21D ASBMs with maneuverable warheads that are guided by terminal seekers. That way, even with slightly inaccurate ISR data, the terminal seeker could steer a warhead towards its target, so long as the seeker can identify that target and the guidance it provides is within the warhead’s ability to maneuver. Of course, creating such a seeker is no mean feat. It will have to function not only at hypersonic speeds, but also while encased in the plasma that forms around a warhead as it plunges through the atmosphere.
Naturally, the types of terminal seeker that China might use are also important. One type is an electro-optical seeker, which uses the spectral signature (i.e., image) of a target to identify it. Unfortunately, atmospheric conditions (i.e., clouds) and hours of darkness can often get in the way. An infrared seeker can overcome those shortcomings by using a target’s heat signature for identification.
However, even the best infrared seeker is open to spoofing with technology that either masks or mimics heat radiation. A third type is an active-radar seeker, which identifies a target using its radar cross-section; it, too, can be fooled. While an ideal terminal seeker is likely one that combines multiple sensors, such a seeker would be more difficult to manufacture, given a warhead’s size and weight constraints.
To be sure, China’s potential adversaries are aware of its ambitions to target ships at sea with ASBMs. They have once again begun to train their navies to strictly manage their electronic emissions to evade China’s ISR collection assets. Within the South China Sea, however, the time when such basic countermeasures are enough may be dwindling.
While it may never be publicly known whether China’s 2019 or 2020 ASBM firings into the South China Sea were directed against mobile or fixed targets (or whether they were successful or not), the fact that the missile firings occurred at all so close to waters where commercial and naval ships often ply suggests that China was reasonably confident that its missiles would not hit those ships. Of course, that does not imply that China’s ASBM capability has become operational—it does imply that it may be one step closer.
China’s Anti-Ship Ballistic Missile Capability in the South China Sea
Source Foreign Policy Research Institute