China's Achilles' Heel: Air Defense Gap

Holes in Coverage? Possible gaps in Chinese radar coverage might have been found by intelligence-gathering aircraft, such as the RC-135 Rivet Joint, a China analyst says. (US Air Force)

TAIPEI — Only days after China declared an air defense identification zone on Nov. 23 over the East China Sea, the US Air Force flew two B-52 bombers over the area in what appeared to be a challenge to China’s claim.

A former US Air Force official is suggesting this was a message of deterrence to Beijing that the US is aware of China’s weak links along its air defense network.

Two separate groups control the coastal radar perimeter along China’s coast: the People’s Liberation Army Navy (PLAN) and the PLA Air Force (PLAAF), said Mark Stokes, a China military specialist at the Project 2049 Institute.

The weakest link in China’s air defense network is where these two meet — PLAN’s Second Radar Brigade in Zhejiang province’s Cangnan City, and PLAAF’s Fourth Radar Brigade in Fujian province’s Fuding City, along the border of Zhejiang province.

This gap runs along the southern line of the East China Sea air identification zone.

China’s new zone is both “figuratively and literally a military ‘line in the sand,’ ” said Paul Giarra, president of Global Strategies and Transformation.

Stokes made the conclusions after compiling a report issued in late April on the Taiwan website Think Taiwan, a product of Tsai Ing-wen’s Thinking Taiwan Foundation. Tsai was a 2008 Democratic Progressive Party presidential candidate, losing to the Chinese Nationalist Party’s Ma Ying-jeou.

Stokes, who was in Taiwan last week, said it is likely that a US electronic intelligence collection aircraft, possibly an RC-135, was flying in the area gathering data on the Chinese radars as they activated. This data could later be used to jam and confuse China’s radars during a conflict, such as over the Senkaku Islands, claimed by both China and Japan. RC-135s are deployed in the area under the 82nd Reconnaissance Squadron based at Kadena Air Base, Okinawa. The B-52s most likely originated out of Andersen Air Force Base on Guam.

Stokes, a former US Air Force attaché assigned to Beijing in the 1990s who later served on the China desk under the Office of the Secretary of Defense, said this gap is the key entryway for US fighters and bombers during a conflict.

These “holes” along China’s coast would allow US air power to knock out “critical nodes” that serve as the command-and-control hubs of radars and surface-to-air missiles. The US must destroy these “single points of failure” before continuing with attacks on other Chinese military threats, such as cruise missile and short-range ballistic missile units.

The one exception to this rule is the large phased array radar at Zhejiang, which is not under PLAN or PLAAF control. This facility is responsible for space signal intelligence collection and belongs to the PLA’s General Staff Department.

Stokes has identified the structure of China’s ground-based air surveillance and the bureaucratic interplay that likely led to the first air identification zone, said Richard Fisher, senior fellow, Asian Military Affairs, International Assessment and Strategy Center.

“However, Stokes does not delve into radar types and capabilities that would better allow for assessing such gaps,” he said. If gaps exist in radar coverage, they would be “pronounced” at longer ranges.

Stokes said gaps in China’s air defense network would eventually be filled by radar advancements and the implementation of a new “automated joint air surveillance system” in the coming years.

Giarra said China is treating these “marginal air zones as territorial air space” and is making it clear that it is “continuing the implicit seizure of military control of its maritime and air approaches on its sea frontier.”

To further complicate issues, Chinese plans to impose air identification zones in the South China Sea would “squeeze Taiwan’s airspace,” Stokes said. However, a South China Sea zone would also illuminate China’s air defense strengths and weaknesses, just as the East China Sea zone did, he said.

“The declaration of an [air ID zone] naturally should attract interest in the air defense system behind it,” he said. “It would be kind of hard to interdict single points of failure in a PLA air/missile campaign and ‘break the kill chain’ without understanding how the integrated air defense system works.

“From this perspective, the ADIZ is fairly enlightening.” ■

Email: wminnick@defensenews.com.

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