A Boeing Co. 737 MAX operated by MIAT Mongolian Airlines landed in China on Oct. 10 in what industry experts say is the jet’s first commercial flight in Chinese skies since Beijing grounded the plane in 2019.

The round-trip flight with passengers, between Ulaanbaatar and Guangzhou, landed in the southern Chinese city at 8:18am local time, according to FlightRadar24 data. MIAT Mongolian Airlines has the trip scheduled to fly again, using the 737 Max, on Oct. 17 and Oct. 24. Both are listed on the carrier’s website.

MIAT received all necessary permission in August to operate the Max into China, and no special permit was required for the Oct. 10 flight, a spokesperson for the carrier said in an email. “The aircraft has undergone all of the work related to the safety bulletins issued by Boeing and authorities and is safe to operate,” the spokesperson said.

Boeing’s shares pared a gain of as much as 4.6% to trade up 1.9% to $132.19 as of 11:14 a.m. in New York. The stock is down about 34% this year. 

The move is being closely watched as a potential signal the model may be closer to a return to service by Chinese carriers. Boeing officials met with China’s aviation regulator last month to review pilot training criteria for its Max jetliners, in a sign the plane-maker is getting closer to securing all the necessary approvals to get the Max back up and flying in China -- the last remaining major aviation market not to permit its resumption.

“We continue to work with global regulators and our customers to safely return the 737 Max to service worldwide,” Boeing said in an e-mailed statement, declining to comment further. 

China was the first to ground the Max in March 2019 and held off approving its return long after U.S. regulators lifted a ban in late 2020 and Europe and other places followed in subsequent months. Returning the 737 Max to the skies in China and resuming deliveries are critical steps toward helping rebuild Boeing’s balance sheet, which was battered by the lengthy Max grounding and the Covid pandemic.

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Chinese airlines haven’t flown the plane commercially since two fatal crashes involving the model in October 2018 and March 2019 in Indonesia and Ethiopia, respectively, that combined killed 346 people. Boeing has said it is diverting some 737 Max jets earmarked for China to other buyers. 

The aircraft that operated Monday’s service to Guangzhou had been leased on a short-term basis to TunisAir this summer, and MIAT got it back last week, the spokesperson said.