David An is a senior research fellow at the Global Taiwan Institute and was previously a political military officer at the US Department of State.
“Recent unilateral actions by #China—including M-503 flight route & increased military exercises—are destabilizing & should be avoided,” Taiwan’s President Tsai Ing-wen wrote on January 5, 2018. Her tweet was in response to China’s establishment of a new northbound M-503 flight route for commercial passenger airliners along the centerline of the Taiwan Strait the day before. How can a commercial airline flight route be tied together with “military exercises” and “stability” all within one sentence? Or within 140 characters of the same tweet?
This commercial passenger airline matter is important enough to spur a back and forth series of flight cancellations between China and Taiwan, affecting tens of thousands of passengers and costing airline companies millions of dollars. Two major PRC airline companies, China Eastern Airways and Xiamen Airlines, said they cancelled flights to and from Taiwan during the Lunar New Year, for a total of 176 round trip flights, because Taiwan refused to approve them. Taiwan’s Civil Aeronautics Administration (CAA) estimates that up to 50,000 passengers could have been affected. China Eastern Airlines released a statement stating that Taiwan’s failure to approve the flights, “seriously infringed upon the common interests of our company and customers, and severely violated the humanitarian needs of thousands of passengers and families.” The stakes are surprisingly high over a new passenger airline route.
Unilateral action and geographical concerns
Taiwan said it was not consulted over the routes the flights would take, and considering that China took unilateral action, Taiwan therefore withheld approvals for China Eastern Airways and Xiamen Airlines because both had used the disputed air routes. Taiwan’s Civil Aeronautics Administration (CAA) reports that over 20 flights, which are operated by Chinese airlines, use the new routes every day. Taiwan’s CAA confirmed that it provisionally delayed approval of applications of these two China based airlines to operate additional cross-Strait flights during the Lunar New Year holiday in protest against China’s decision to implement the northbound M-503 route.
Essentially, the importance of the M-503 flight route is exactly because it is located along the centerline of the Taiwan Strait. M-503 northbound is one among four new flight routes that China opened on January 4, with aircraft using these routes that same day. Taiwan has protested the opening of the routes precisely due to the unilateral nature of China’s announcement and the location of the routes. M-503 northbound is merely 4.2 nautical miles west of the centerline, with a real possibility that aircraft could cross over to the other side; and I wrote a previous Global Taiwan Brief article about the longstanding norm for China and Taiwan to stay to their own sides of the centerline along the Strait. In addition, Taiwan’s Mainland Affairs Council Minister Katherine Chang (張小月) demanded an immediate end to the M-503 north route the same day it was established. Essentially, the geography of M-503 combines several sensitivities within this one issue: airline flight safety, and even many military strategy concerns.
Commercial airline flight route safety concerns
Taiwan has raised concerns that the new flight routes are too close to existing routes that connect its airports to two groups of Taiwan controlled islands located close to China, and are therefore a threat to flight safety. Among the four new routes, three new Chinese east to west extension routes designated as W121, W122, and W123 now overlap with Taiwan’s W6, W8, and W2 flight routes connecting Taiwan with its islands, Kinmen and Matsu. However, a spokesman for China’s Taiwan Affairs Office countered that a distance of 14 miles separates these routes, so he claims that they are considered safe according to International Civil Aviation Organization standards. Nonetheless, Mainland Affairs Council Deputy Minister Chiu Chui-cheng (邱垂正), urged China to negotiate with Taiwan about the new flight routes, and that “aviation safety is the core issue and people’s lives must not be put at risk.”
The Civil Aviation Administration of China (CAAC) said, “[t]he rapid growth of flights in western Taiwan Strait airspace in recent years has caused increasingly serious delays,” and that the new flight paths therefore alleviate congestion. However, even China’s official state-sponsored China Daily newspaper notes that the People’s Liberation Army (PLA) Air Force has a tight grip on China’s airspace. It cited an aviation expert who stated that less than 30 percent of China’s airspace could be used by civilian airlines, which is in contrast with the United States 85 percent airspace for civilian use. According to some estimates, China’s PLA controls up to four fifths of China’s air space. In this sense, any flight congestion is China’s own doing, and it could have opened up more PLA airspace rather than unilaterally opening up a politically sensitive northbound M-503 route.
Military strategic concerns
Referring to the M-503 issue, Taiwan’s Mainland Affairs Council stated, “[t]his is purposefully using civilian aviation as a cover for improper intentions regarding Taiwan politics and even military affairs.” Several military strategic concerns come to mind. First, there is a possibility that China could fly its reconnaissance or other military aircraft along this same route as if they were passenger or cargo planes, to then collect intelligence on Taiwan’s air bases, defense deployments, and infrastructure along Taiwan’s west coast. Taiwan also fears that Chinese military aircraft could evade radar detection by staying close behind civilian jets.
Second, not only do these four new routes run along the centerline of the Taiwan Strait, but they are also close to Taiwan’s air-defense identification zone, which Taiwan uses to monitor possible military incursions into its airspace. Referencing the M-503 situation in an evening broadcast on January 22, President Tsai raised the possibility of a Chinese attack on the island.
Third, according to Research Fellow Ian Easton at the Project 2049 Institute, the new M-503 air route makes it easier for China to launch a first strike. Easton notes that, “given the close-in nature of the standoff, early warning time is vital for stability,” and “it’s being further constricted.” Indeed, Taiwan’s Ministry of Defense said that the military will intercept, warn, and repel if necessary, any aircraft that crosses into Taiwanese airspace and puts the island’s security in jeopardy.
Fourth, additional flights along the centerline of the Taiwan Strait could muddle the “target picture” or “target environment” in a potential conflict scenario. An academic thesis paper for the US Naval Postgraduate School describes how radars become strained when tracking a large collection of targets, and should then hand off targets between radars. It essentially explains the basis for why sending additional passenger aircraft in areas as sensitive as the middle of the Taiwan Strait will make it hard for Taiwan to perform “identification friend or foe” (IFF).
If all signs show that China is planning military aggression toward Taiwan, and if Taiwan accidentally shot down a civilian passenger aircraft in the midst of other military targets, the result would be disastrous. It is puzzling that Taiwan and China reached an agreement in 2015 to even allow southbound flights along the M-503 flight path, but additional northbound flights would make the matter even more risky. Such security concerns may have seemed to be farfetched in 2015, which was the last time China and Taiwan discussed the M-503 flight path. However, these concerns are increasingly realistic in today’s context, and in light of the new features emerging in the past two to three years, such as the case of China’s Liaoning aircraft carrier recently passing through the Taiwan Strait, and China’s military aircraft flights encircling Taiwan.
It is not unthinkable that Taiwan could accidentally shoot down a civilian aircraft, considering that the Taiwan Navy accidentally launched an indigenously produced Hsiung Feng III missile during a drill that reportedly hit a fishing boat, killing one person and injuring three. If Taiwan had hit a Chinese PLA Navy vessel instead, there may have been dangerous escalation of violence.
Rather than basing M-503 on safety or security concerns, Wang Hailiang—Taiwan Studies researcher at the Shanghai Academy of Social Sciences—believes that the Tsai Administration is seizing the M-503 situation, considering that China has cut off official channels with Taiwan since Tsai’s election into office in 2016. China claims that President Tsai Ing-wen does not recognize the “1992 Consensus.” With no formal mechanism to negotiate the air routes, Taiwan must either make compromises that are not in its interests, or block the airlines altogether. Tsai has criticized China for creating the situation in couched terms: “Even if Taiwan makes an unnecessary compromise over the question of new air routes, it cannot secure chances of dialogue with China.”
Considering that Taiwan’s president tweeted about the security concerns of a new northbound M-503 flight path, it is worth parsing out the various factors and perspectives inherent in this controversy. The heated rhetoric between Taiwan and China, and cancelled flights, have not been for nothing— northbound M-503 does pose a series of potential flight safety and military strategy risks for Taiwan. Although both sides agreed upon a southbound M-503 route in 2015, it does not negate the concerns that come with adding more flights along such a sensitive route.
The main point: A pre-existing southbound M-503 route negotiated in 2015 does not justify a new northbound M-503 route that China unilaterally implemented on January 4. Flying additional aircraft along this new northbound M-503 route risks the possibility that China could fly military surveillance aircraft along the same route, edge closer to Taiwan’s air defense identification zone, more easily launch a first strike against Taiwan, and clutter the “target environment” that Taiwan faces in a potential conflict scenario.