The air-traffic disruption delivered another blow to travelers already plagued by flight delays and cancellations. It also underscored the challenges faced by commercial airlines in China, where military flights are given precedence over civilian ones.
China's Air Traffic Management Bureau, a unit of the nation's aviation regulator, issued the restriction on two Shanghai airports—Shanghai Hongqiao International Airport, which mostly handles domestic traffic, and Shanghai Pudong International Airport—for flights between 2 and 6 p.m. Tuesday, said two airline officials based in Shanghai. More than a dozen smaller airports in eastern and southern China also halted flight arrivals and departures during the period, the air-traffic bureau said.
China's Ministry of National Defense coordinated the exercises, which it said were routine and designed to test the military's combat capability, according to a statement on the ministry's website. The ministry gave no details about the precise location or schedule of the drills.
The reduction is part of a three-week curb on flights through mid-August because of the drills. So far the restrictions have resulted in capacity reduction of as much as 25% at a dozen Chinese airports, including the two in Shanghai, airline officials said.
The aviation regulator said last week that "rainstorms, routine military exercises and other comprehensive factors" are behind widespread flight delays and cancellations in the second half of July.
It has stopped applications for executive aircraft, additional scheduled flights and chartered flights at affected airports.
Eric Lin, an aviation analyst at UBS Securities, said the latest flight reduction is especially damaging for the air-travel industry in eastern China, which has already faced flight delays and cancellations caused by adverse weather conditions.
"The scale of the military drills and its duration is rarely heard of, and one that falls into a traditional peak season for air travel would definitely have an impact on airlines' profitability," Mr. Lin said.
The curbs have added pressure on China's already congested airspace for civil aviation. Shanghai-based China Eastern Airlines Corp. canceled 22 flights scheduled for Tuesday and Wednesday because of rainstorms and airspace restrictions, it said on its official Weibo microblog account Monday, adding to hundreds of flight cancellations since the middle of July. At the two Shanghai airports, a total of 135 departure and arrival flights were canceled and an additional 428 were delayed as of Tuesday afternoon, according to flight-tracking organization FlightStats.
On Monday, 119 flights were canceled at the two Shanghai airports, accounting for 30% of the 397 flights canceled at Asian-Pacific airports, according to FlightStats. An additional 1,116 departures and arrivals were delayed at the two airports on the same day, accounting for 16% of delays in the region.
Air travel in China is booming, with passenger traffic in the first five months up 12% from a year earlier after an 11% rise in 2013, even as the nation's economic growth slows. However, the nation's airports and airlines are among the worst in the world in getting flights off on time.
Aviation experts cite military control of China's skies and inefficient operations at Chinese airports among reasons leading to excessive delays. Roughly 20% of available airspace is allotted to civil aviation and the remainder is tightly held by the military, the aviation regulator has said. In the U.S., by contrast, there are few restrictions for general aviation usage on most airspace apart from that over major metropolitan areas.
Even without the latest curbs, flight delays and cancellations are common at many Chinese airports.
Winnie Poon, former chairwoman of Dragonair's flight-attendants union, said it isn't unusual for a round-trip flight between Hong Kong and Shanghai—which usually takes about 2 1/2 hours one way—to return to Hong Kong three hours late.
Zhang Qihuai, a Beijing-based lawyer and frequent traveler, said the government should balance the interest of China's military exercises for defense purposes with ordinary people's lives. "Military drills should not disrupt ordinary people's travel plans," he said.
Mr. Zhang, who has in the past altered travel plans to Shanghai several times because of persistent delays and cancellations, said he would consider making further changes because of the traffic curbs. "I would opt for the high-speed train instead of traveling by air if I really have to travel to Shanghai," he said.
Analysts estimate the traffic curbs will reduce China Eastern's revenue by 1% to 2% on an annualized basis. Other Shanghai-based airlines such as Spring Airlines Co., China's biggest budget carrier, and Hong Kong-based Dragonair, a China-focused unit of Cathay Pacific Airways Ltd., will also be affected by the traffic restrictions, they say.
James Wang, an official at China Eastern, said aviation regulators notified the airline of the traffic curbs.
"We were told that airspace over eastern China is occupied by other users at some time slots, and we have adjusted our flight schedules and alerted our customers accordingly," he said, without elaborating.
He said the airline cut its number of flights by less than 25% but declined to disclose the exact percentage.
Zhang Wuan, a spokesman at Spring Air, said that it also received notices from aviation authorities about the traffic restrictions.
"It definitely has an impact on our business during the travel peak," he said. However, he said that regulators' decision to give earlier notices about the restrictions could enhance transparency to the public and alert travelers so they could adjust their plans.
And unless such large-scale flight reductions become regular, they aren't likely to affect China's demand for air travel, which is expected to grow in a range of 9% to 10% in the foreseeable future despite the nation's economic slowdown, said UBS's Mr. Lin.
Source: Wall Street Journal by Joanne Chiu