China Southern Airlines, Air China and China Eastern Airlines have logged a combined net loss of 49.6 billion yuan (US$7.19 billion) for the first half, ballooning from the year-earlier 16.6 billion yuan. Revenue declined 32% to 84.1 billion yuan.

Air China bled the most red ink, with its loss widening to 19.4 billion yuan from 6.7 billion yuan.

“Air transport production continued to be under pressure due to the impact of pandemic,” the carrier said in its interim earnings report Tuesday.

Since 2020, China has extensively restricted the number of international flights operated by airlines both foreign and domestic in the interest of keeping the coronavirus out. It has also made use of circuit breaker measures that suspend flights, depending on the number of infected passengers found among international arrivals.

Against this backdrop, the big three have discounted tickets to gin up demand for domestic travel. But in the first half, Shanghai and other cities were put under lengthy lockdowns to combat Covid-19.

The plunge in domestic travel with the movement restrictions in place damaged the airline industry’s lifeline once again.

China’s civil aviation authority is gradually increasing the number of inbound flights allowed. The use of circuit breakers has also been eased. But China’s zero-Covid policy remains firmly in place, meaning that the airlines will continue to face a harsh business environment.