September 12, 2022: While the U.S. Navy has been quiet about how it plans to defend its ships against Chinese ship-killer ballistic missiles, they have not been idle. The navy has quietly expanded its layered air defense system with the addition of new electronic defenses. The navy is particularly quiet about any efforts to conduct realistic tests of its defenses against Chinese ballistic missiles.

After two decades of effort, the Chinese Navy has developed and tested its DF-21D ballistic missile equipped to hit warships at sea and over a thousand kilometers distant. The basic DF-21 is a 15 ton, two stage, solid fuel missile that is 10.7 meters (35 feet) long and 140cm (4.6 feet) in diameter. Range varies (from 1,700-3,000 kilometers) depending on model. The DF-21D is believed to have a range of 1,500-2,000 kilometers. While the 500-2,000 kg (.5-2 ton) warhead usually contains a nuclear weapon, there are also several types of conventional warheads, including one designed for use against warships. Some of these conventional warheads are for use against targets in Taiwan. This is because the DF-21, as a longer-range ballistic missile that comes down on the target faster than the 1,200 shorter-range ballistic missiles aimed at Taiwan, is more difficult to intercept. The DF-21D warheads were too fast for the American Patriot Pac-3 BMD (Ballistic Missile Defense) missiles Taiwan was installing around crucial installations a decade ago. BMDs have improved since then, but so has the Chinese ballistic missile arsenal.

In 2020 China tested the DF-26B, a longer-range version of the DF-21D. The 20-ton DF-26B has a max range of 4,000 kilometers. This is a larger 14-meter long 140cm diameter missile that entered service in 2016 as the conventional DF-26. By this time the DF-21D had been tested and proved that it could work. Why not a larger version that could hit enemy warships, especially aircraft carriers, even farther away? Five years later the DF-26B was tested and in service. By 2022 China had the smaller YJ-21 missile that could be carried by bombers or large (destroyers or cruisers) warships and use the same target detection tech as the DF-21D and DF-26B to hit distant ships.

Until 2013 there was no evidence that the complete DF-21D system had been tested. But then satellite photos showed a 200-meter-long white rectangle in the Gobi Desert (in Western China) with two large craters in it. This would appear to be a “target” for testing the DF-21D, and two of the inert practice warheads appear to have hit the target. American carriers are over 300 meters long, although the smaller carriers (amphibious ships with helicopter decks) are closer to 200 meters long. It appears China is planning on using the DF-21D against smaller warships, or perhaps they just wanted to see exactly how accurate the missile could be.

Over the last five years several similar missile testing sites were discovered in the vast desert areas of western China. Some of these test targets portrayed air bases or even larger targets like naval or army supply depots as well as harbors where American warships are regularly found. China was seeking a way to carry out another Pearl Harbor type attack and they appear to have found it.

Out in the desert China also found ways to improve the accuracy and reliability of their remote-sensing satellite. Back in 2011 an odd, geometric pattern was spotted in a Chinese desert that was used to calibrate satellite sensors, including those used to locate and identify targets for DF-21D type missiles.

For three years (2011-13) various components of the DF-21D were tested, but until these satellite photos showed up there was no evidence that there had been any tests of the complete system against a carrier size target. Since 2012 there have been photos of DF-21Ds on TELs (transporter erector launcher vehicles), and announcements of the first units activated three years ago. By 2013 there was evidence of the successful tests. What has not been tested, apparently, is a “dress rehearsal” test against a large ship (an old tanker or container ship would do) at sea and moving. That might yet happen.

Before the 2013 tests China put three "remote sensing" satellites in orbit, moving in formation at an altitude of 600 kilometers across the Pacific. Equipped with either radar (SAR or synthetic aperture radar) or digital cameras, these three birds can scan the ocean for ships, even though the Chinese say their purpose is purely scientific. A typical SAR can produce photo quality images at different resolutions. At medium resolution (3 meters) the radar covers an area 40x40 kilometers. Low resolution (20 meters) covers 100x100 kilometers. This three satellite Chinese posse looks suspiciously like a military ocean surveillance system. This is the missing link for the Chinese ballistic missile system designed to attack American aircraft carriers.

China has been developing the DF-21D since about 2002. Most of the development effort was devoted to targeting systems that would enable them to seek out and find aircraft carriers. On the DF-21D warhead itself, sensors would use infrared (heat seeking) technology for their final approach. This sort of thing had been discussed for decades, but China appears to have put together tactics, sensors, and missile systems that can make this all happen. The key was having multiple sensor systems which would include satellites, submarines, or maritime patrol aircraft that could find the general location of the carrier before launching the ballistic missile. Those sensors were eventually revealed as operational, as was the DF-21D itself.

Meanwhile the U.S. Navy has quietly upgraded its ABM defenses that use short range RAM (Rolling Airframe Missile) and long-range SM-2 missiles that have proved very effective against ballistic missiles and, in one case, a space satellite. The navy is more secretive when it comes to its electronic defenses, which involve lasers and other light-based devices as well as a growing assortment of electronic devices that apparently concentrate on disabling or diminishing the terminal guidance systems of the ballistic missiles that make them accurate enough to hit individual ships. The navy and air force are apparently also developing techniques for disabling China’s remote sensing satellites. Developing multiple attacks on Chinese satellites and ballistic missile sensors is what the layered defenses are all about. This adds a degree of uncertainty about the usefulness of the Chinese anti-ship ballistic missiles. Uncertainty is a goal here and one of the more important aspects of the layered defense systems. The Chinese can collect some details about the new American electronic defenses by following announcements in the trade journals, where new features are mentioned, although not always with links to any specific navy system being upgraded. A lot of Chinese espionage, using human agents or hacking, is devoted to sorting out that specific new capabilities the Americans have introduced and for what piece of equipment.