China Eastern Airlines has officially stated that pilots in its Yunnan subsidiary deliberately turned back midway through their provincial flights out of Kunming on Monday and Tuesday of last week – effectively going on strike in midair, according to a China Daily report.

According to the report, all pilots from the total of 21 affected flights have been suspended from their jobs. An internal investigation by China Eastern and a probe by aviation regulator Civil Aviation Administration of China (CAAC) are both currently underway.

China Eastern released a statement yesterday saying that two high-ranking officials in the company's Yunnan subsidiary have been fired and a deputy general manager from the company's Shanghai headquarters has been named head of the branch, where he will investigate the reason for the rare demonstration.

The China Daily report said the reason for the mid-air pilot strike was related to grievances related to low pay for pilots of feeder routes such as those within Yunnan as well as overtime and night shift-related issues. But a report last week on China.org.cn attributed the disrupted flights to pilot anger regarding restrictive contracts aimed at preventing poaching by other airlines:

Pilots in state-owned companies have been forced to sign 99-year contracts with their employers. If they quit, they must pay compensation ranging from 700,000 to 2.1 million yuan.

While China Eastern and CAAC investigate the incidents of last week, passengers on the disrupted flights continue to seek compensation. China Eastern said it has compensated some of the passengers and will eventually compensate all of those affected.

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