Chinese airline Lucky Air has removed one of its pilots from his position after passengers disembarked to protest the delay of their flight, party-affiliated newspaper Beijing Youth Daily reported Wednesday.

The company’s decision follows an incident on Monday at Xishuangbanna Gasa Airport in China’s southwestern province of Yunnan. During the three-hour delay of a Lucky Air flight to provincial capital Kunming, the airplane’s captain allowed passengers to disembark onto the tarmac, reportedly to protest the fact that other flights had been allowed ahead in the takeoff queue.

In a video clip by online news platform Pear Video, a passenger identified by only the surname Guo said that the pilot had told passengers they could disembark. “[The captain] said that he had faced the same situation several times,” Guo explained.

According to flight-tracking website Flightradar24, Lucky Air’s flight from Xishuangbanna to Kunming has an average arrival delay of 2 hours and 17 minutes.

Guo said that airport security personnel came to stop the passengers, but no one listened to them. In the video, the captain is seen telling passengers to get back on the plane, but some passengers refuse. “We support you,” a voice in the video says. “We won’t leave!”

Lucky Air said it is conducting an internal investigation and that it will educate its staff to prevent the situation from recurring. The budget airline is a subsidiary of Hainan Airlines and was established in 2006. Based in Yunnan province, the airline has 27 passenger planes that fly 69 mostly domestic routes.

In China, air traffic control gives priority to international flights and flights with important clients, including politicians, business tycoons, and aviation industry VIPs, according to a media report.

In recent years, the on-time performance of flights in China has been slipping. Official figures show that in 2008, more than 80 percent of flights were on schedule. By 2015, that number had dropped to 69 percent, with about half of the delays attributed to weather and air traffic congestion.

To complicate matters further, reportedly only about 20 percent of China’s airspace is available to commercial flights; the rest is reserved for the military. In comparison, about 80 percent of airspace in the U.S. is available to civilian aircrafts. Aviation expert Lin Zhijie told Sixth Tone that the majority of airports in China have adopted measures to improve efficiency, but that this does not resolve the underlying issue. “The most fundamental problem is the lack of available airspace,” he said.

Additional reporting by Lin Qiqing.

This article has been updated with additional information.

(Header image: A Lucky Air airliner is seen at Kunming Changshui International Airport, Yunnan province, March 19, 2016. VCG)