BEIJING (NYTIMES) - Record-breaking numbers of Chinese military planes probed the airspace near Taiwan over the weekend, prompting Taiwanese fighter jets to scramble and adding muscle to Beijing's warnings that it could ultimately use force to take hold of the island.
The sorties by nearly 80 People's Liberation Army aircraft on Friday (Oct 1) and Saturday, as China observed its National Day holiday, followed a pattern of Beijing testing and wearing down Taiwan by flying over seas south-west of the island.
The most recent flights stood out because of the number and types of planes involved, including bombers and anti-submarine planes on night-time intrusions.
The flights did not suggest an imminent threat of war over Taiwan, said several analysts, but they did reflect Beijing's increasingly unabashed signalling that it wants to absorb the self-ruled island and will not rule out military means to do so.
"Coming on Oct 1, China's National Day, it sends a message about Beijing's determination to claim Taiwan, by force if necessary," said Mr Adam Ni, an Australian analyst of Chinese military policy who is based in Germany. "The aim of this is to assert Beijing's power and show military muscle."
Taiwan's Ministry of National Defence said that the spike in flights began on Friday, when 38 Chinese military planes flew into the island's "air defence identification zone".
The first group of aircraft included two H-6 bombers and 22 fighter jets, according to the Taiwanese ministry.
That night, another two H-6 bombers, accompanied by 10 J-16 fighters, flew into the air zone, turned left off the southern end of Taiwan and headed north-east, parallel to the island's eastern coast, before turning back, it showed on a map.
On Saturday, 39 Chinese military planes - including fighter jets, two anti-submarine aircraft and an early-warning-and-control plane - entered the Taiwanese zone, again breaking the daily record, the ministry said.
On Sunday, 16 more planes, including a dozen fighter jets, cut into a corner of the same area of the zone, it said.
Taiwan's air identification zone dates to the 1950s, laying out the airspace where the island's authorities assert the right to tell entering planes to identify themselves and their purpose.
It is a much larger area than Taiwan's sovereign airspace, which reaches 12 nautical miles from its coast. The Chinese flights did not enter that sovereign airspace.
"It is very worrying," said security analyst Chieh Chung with the National Policy Foundation in Taipei. "This puts a lot more pressure on our military, and the more they reach into our airspace, the greater the risk of some kind of accident."
Taiwan's defence ministry began regularly releasing records of Chinese military flights into the space in September of last year. Chinese military planes now enter the zone nearly every day, and the latest waves have barely ruffled most people in Taiwan.
Officials on the island sounded more worried, however.
"Threatening? Of course," Taiwan Foreign Minister Joseph Wu said on Twitter, after the spike of intrusions began on Friday.
In answer to questions about the Chinese flights, the Taiwanese defence ministry said on Sunday that it was "maintaining a high degree of vigilance and responding appropriately to ensure national security".
The United States State Department condemned what it called China's "provocative military activity near Taiwan".
Mr Ned Price, a spokesman for the department, said on Sunday that the action was "destabilising, risks miscalculations and undermines regional peace and stability".
Taiwan's military responded to the latest Chinese flights by sending its own fighter jets into the air to monitor, but not confront, the planes.
The strain of responding to China's regular intrusions is wearing on Taiwanese pilots and aircraft, and it could be affecting the island's overall vigilance, experts said.
"What I think is clear is that they're having some success wearing down Taiwan with this operational tempo," American Enterprise Institute senior fellow Zack Cooper, who studies Chinese and regional military issues, said in an interview. "It's tough on the pilots, it uses gas, which is expensive, and these air frames - the more you use them, the quicker they age."
The Chinese government has said nothing about the flights, while official Chinese news outlets cited the Taiwanese reports that they had set a record.
The flights "clearly and unmistakably displayed China's sovereignty over Taiwan", the Global Times, a pugnaciously nationalist Chinese newspaper, said in an editorial. "The greater the number of combat planes gathering together, the more it shows that our military is forming a powerful wartime aerial assault force."
China's flights into the Taiwanese zone usually feature slower-moving reconnaissance and anti-submarine aircraft, as well as fighter jets, according to records compiled by Mr Gerald C. Brown, a defence analyst in Washington.
But this year, Mr Brown's data indicates, the Chinese air force has sent bombers more often - an intimidating step, because it could more likely carry out a real attack.
The large-scale night flights also suggested that Chinese pilots had honed their abilities to fly their J-16 fighter jets in darkness, said Dr Su Tzu-yun, a senior analyst at the Taipei-based Institute for National Defence and Security Research, which is backed by Taiwan's government.
"They are trying to show all-weather capability," said Dr Su. "They want to show that they can fight battles in the daytime and try to strike at night-time."
By the end of 2019, China had around 1,500 fighter jets and 450 bombers and attack planes, according to the Pentagon's 2020 report on the People's Liberation Army. Taiwan had 400 fighters and no bombers.
Taiwan's security increasingly depends on the US, which provides most of its weapons. Under a 1979 law, the US could intervene in an attempted military takeover of Taiwan, but it is not obliged to do so.