China has been busy in the skies around Taiwan and shows no signs of stopping. Beijing concluded 2017 with a series of high-profile exercises by the People’s Liberation Army Air Force (PLAAF) circumnavigating Taiwan. The year 2018 started with a breach of an agreement from March 2015 to restrict an already controversial M503 flight route for southbound traffic by announcing the opening of the route for northbound traffic. Furthermore, the Civil Aviation Administration of China (CAAC) also announced the opening of three additional east-west routes connecting M503 with China, two of them close to Taiwan’s outlying islands of Kinmen and Matsu.

Both developments have direct implications for Taiwan’s defense posture. M503 is close to Taiwanese air force (ROCAF) training areas, while the W122 and W123 routes pass by Taiwan’s forward-deployed defenses on Matsu and Kinmen. ROCAF training areas are sandwiched between two civilian corridors: M503 and long-established routes along Taiwan’s western coastline. The Taiwanese air force previously vacated one of its training zones after Beijing announced its East China Sea Air Defense Identification Zone (ADIZ) in 2013. Thus, M503 is already affecting the ROCAF’s freedom of action. Moreover, the ability of Taiwanese combat air patrols (CAP) to respond to regular PLAAF patrols buzzing along Taiwan and to monitor moves by PLA Navy vessels through the Taiwan Strait will be restricted. In a 2015 piece for Thinking Taiwan on the implications of M503 for Taiwan, I made an observation that appears to have been since validated by China’s actions:

Regardless of all the implications for ROCAF training, the M503 is still not a threat to national security — at least, not yet. If and when Beijing decides to put pressure on the ROCAF, it will do so overtly. For example, an increased number of patrols close to the median line that might cross into the Taiwan side “by mistake” and regular incursions into Taiwan’s ADIZ, similar to the one in August last year, would become the norm. Each of these actions would prompt the ROCAF to scramble interceptors (which would, in turn, help Beijing learn new information about Taiwan’s air defense response time).

Stepping-up activity along Taiwan’s ADIZ, forcing Taiwan to scramble fighters in response, is precisely what Beijing’s next step turned out to be. However, the real danger lies in China’s push for a gradual change in the status quo in the skies over the Strait.

The recently published National Defense Report identifies 23 PLA exercises between September 2016 and December 2017. That number may not sound too high, except that it is in addition to the usual response of Taiwan’s CAPs to PLAAF activity.

Moreover, if we consider the types of planes that took part in those exercises and the routes they followed, it gives us a clearer picture of what Beijing’s purpose might be. The yellow course on the NDR graphics indicates missions in and out of the Miyako Strait that separates Okinawa and the Miyako Islands, both part of Japan. The red course indicates flights through the Bashi Channel that separates Taiwan and the Philippines. Both of the concerned waterways are strategic access points for the PLAAF and PLA Navy into the Pacific. The pink course indicates PLAAF flights that circumnavigated Taiwan, using the two mentioned waterways as entry/exit points.

The most common type of aircraft that take part in these exercises is the Xian H-6K, a Chinese derivate of Soviet Tupolev Tu-16 bomber entered service in the late 1960s and the closest the PLAAF has to a strategic bomber capability. However, its latest K variant shares only a resemblance to the original version. Its primary mission is not strategic bombing either. In its main combat configuration, the H-6K carries up to six YJ-12 anti-ship missiles or a similar number of CJ-10 land-attack cruise missiles. With this payload, a fleet of H-6K operating east of Taiwan could saturate U.S. Navy fleet missile defenses or target U.S. military bases on Guam. However, fully loaded bombers are easy prey for intercepting fighter jets. U.S. 5^th generation stealth fighters F-22s and F-35s pose a particularly grave danger. This is where the other types of PLAAF combat aircraft that joined the exercises (or combat patrols, as the PLAAF calls them) come into play. The Su-30, one of the most advanced fighter jets in the PLAAF arsenal, would protect bombers against adversary fighters; Shaanxi Y-8, in its electronic counter-measures (ECM) configuration, would provide additional protection for the H-6Ks. All three types were heavily involved in missions around Taiwan, and on several occasions all three were present. On multiple occasions Tu-154 electronic intelligence (ELINT) planes took part, collecting valuable data from Taiwan’s radar installations and other sensors. At least on one occasion, an IL-78MP aerial refueling plane participated, an essential element if China aims to maintain its presence farther from its airfields. Thus, China seeks to involve a broad spectrum of platforms, each with a critical role in extending the PLAAF’s presence east of Taiwan.

Read the rest of the pice on Taiwan Sentinel.

This article was originally published on Taiwan Sentinel, on 8 January 2018.

Michal Thim is a Taiwan defense specialist, a Research Fellow at the Prague-based think-tank Association for International Affairs, a member of CIMSEC, an Asia-Pacific Desk Contributing Analyst for Wikistrat, and a founder of Taiwan in Perspective. Michal tweets @michalthim.