Hundreds of flights to and from Shanghai were delayed or canceled Monday as Chinese authorities imposed strict air traffic control measures reportedly due to military exercises -- the second such near-shutdown of airspace over the metropolis in eight days.

Further interruptions are expected in the coming weeks.

The sudden restrictions have prompted frustration as well as speculation about what’s behind the mysterious controls. On Sunday, two men were arrested for spreading rumors about the July 14 delays and cancellations, the Beijing Youth Daily reported Monday.

The men reportedly posted messages on social media suggesting that the measures were part of a dragnet set up by authorities to catch a high-level official who was attempting to escape a corruption investigation. Thirty-seven other Internet users received related warnings about “fabricating rumors,” the paper said.


Aviation authorities said only that “other users” were occupying the airspace on Monday, leading to severe restrictions from 8 a.m. to noon and 3 p.m. to 7 p.m., fraying travelers’ nerves and leading to heated words between passengers and airline staff. On July 14, authorities also severely limited commercial flights to and from Shanghai between 10 a.m. and 4 p.m.

By midday Monday, 101 flights had been canceled at Pudong International Airport and 103 were delayed by more than two hours, the Civil Aviation Administration of China said. Another 98 flights were canceled at the city’s Hongqiao airport. At Pudong, 74% of arrivals and 36% of departures were delayed; at Hongqiao, 60% of arrivals and 57% of departures were pushed back.

Even without military maneuvers, Shanghai is known as one of the worst cities in Asia for flight delays. According to a December report from FlightStats.com, Hongqiao ranked 31st out of 35 airports in Asia, with only 48% of flights on time. Pudong was worse, with a 43% on-time rate.

About 34% of China’s total airspace is available for civilian use, the state-run China News Service said last year. But commercial airline traffic has been exploding in China; domestic traffic climbed 11.7% from 2012 to 2013, the biggest leap of any market in the world, the International Air Transport Assn. said.


Charles A. Laughlin, a Chinese literature professor at the University of Virginia, was one of the passengers caught up in the July 14 delays. His 11 a.m. flight from Shanghai to Tianjin was held up more than six hours, causing him to miss a lecture he was scheduled to deliver at Nankai University.

As more and more flights backed up, Laughlin said, passengers were left with no place to sit in the terminal and gate staff were unable to provide any estimate of when his flight would take off – until they suddenly announced at 5 p.m. that the flight would be boarding. After another 45-minute wait on board -- during which time the head flight attendant said military maneuvers were to blame for the delay -- the aircraft finally departed.

“The weather was fine ... but the whole departure board was lit up red and yellow with delays and cancellations until the evening,” Laughlin said. “We thought it was odd for military exercises to affect civil aviation for a whole day.”

Tao Yuanyong, a Beijing travel agent, said Monday that he had to assist more than 20 customers who have been delayed by the two episodes in Shanghai. He helped them obtain refunds for their flights and then booked high-speed rail tickets.


“I tell people, if you’re in a rush, take the train,” said Tao, who added that the airlines are not getting much advance notice of the airspace restrictions.

The situation has proved taxing for airline and airport staff. One flight attendant sent out a note Monday on Chinese social media saying, “I hope all the passengers going to east China are tolerant today,” and ending her message with a hashtag meaning “please do not hit me!”

An airport security guard took a more poetic approach, alluding to William Butler Yeats’ line, “Life is a long preparation for something that never happens.”

“Call for information, don’t waste your time in endless waiting,” he added on the Twitter-like service Weibo. “And please do not think naively that when the military drill stops, your flight will [immediately] take off. That’s absolutely impossible!”


More delays and cancellations look to be in the offing. The official Weibo account of a flight attendants’ group said Monday that some airlines had been asked to lower their capacity by 25% through Aug. 15 while military drills continue, affecting 12 airports including Hongqiao and Pudong in Shanghai as well as in the cities of Nanjing, Hangzhou, Hefei, Jinan, Wuxi, Ningbo, Qingdao, Lianyungang, Zhengzhou and Wuhan.

The Civil Aviation Administration of China, the flight attendants group said, would soon release more details.

“Before you take a plane, please prepare enough food and water, and better bring your sleeping bag as well,” the group advised. “If you want to take a plane, it will definitely be delayed. Better choose the high-speed train instead!”

Tommy Yang in The Times’ Beijing bureau contributed to this report.


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