WASHINGTON, Jan 24 (Reuters) - Boeing was set to deliver its first 737 MAX to a Chinese airline since March 2019 on Wednesday, flight data shows, ending a four-year freeze for the U.S. planemaker's most profitable jet.

Here is a timeline of events leading to the restart of Boeing 737 MAX deliveries in China:

2017 MARCH 8 - The 737 MAX gains U.S. Federal Aviation Administration (FAA) certification.

2018 OCT. 29 - A Lion Air MAX plane crashes in Indonesia, killing all 189 people on board.

2019 MARCH 10 - An Ethiopian Airlines MAX crashes, killing all 157 people on board. MARCH 11 - China's aviation regulator becomes the first in the world to ground the MAX. MARCH 13 - The U.S. FAA joins other major global regulators in grounding the MAX. MARCH 14 - Boeing suspends MAX deliveries. Deliveries of three jets to Air China, Shandong Airlines and Xiamen Airlines earlier in the month were Boeing's final deliveries to Chinese carriers until 2023.

2020 NOV. 18 - The FAA lifts the grounding order. DEC. 8 - Boeing restarts 737 MAX deliveries, handing over a jet to United Airlines. DEC. 29 - American Airlines makes the first passenger flight since the MAX was grounded.

2021 JAN. 27 - The European Union Aviation Safety Agency approves the MAX's return to service in Europe.

2023 JAN. 13 - A China Southern MAX flies from Guangzhou to Zhengzhou, marking the model's return to Chinese passenger service. FEB 1 - Hainan Airlines Holding Co Ltd becomes the second Chinese carrier to resume MAX operations. MARCH 3 – Hong Kong’s Greater Bay Airlines places an order with Boeing for 15 737 MAXs – the sole order this year for the MAX from a Chinese airline. APRIL 11 – Boeing says 11 Chinese airlines have resumed 737 MAX operations, with about 45% of Chinese MAX planes back in service. APRIL 14 – China’s aviation regulator releases the second revision of its 737 evaluation report, which Boeing sees as the final technical requirement needed before China can approve restarting MAX deliveries. JUNE 28 - Boeing says about 90% of Chinese 737 MAX jets have resumed commercial operations. JULY 12 – Stan Deal, president of Boeing’s commercial aircraft unit, meets with Song Zhiyong, the head of China’s civil aviation regulator in Beijing. JULY 26 – Boeing Chief Financial Officer Brian West says that Boeing has 85 MAXs of its 220 jet inventory earmarked for Chinese operators after remarketing 55 jets to other customers. AUG. 29 – U.S. Commerce Secretary Gina Raimondo says she did not get any commitments from Chinese officials on the Boeing 737 MAX during a four-day trip to China. SEPT. 1 – Following a report from Aero Analysis Partners/AIR consulting group that tracked the movement of several Chinese MAX planes to Boeing painting facilities in Victorville, California, multiple aviation enthusiasts post photos on social media of MAX aircraft arriving at Seattle-area airports after having been painted with the China Southern paint scheme. NOV. 15 - U.S. President Joe Biden and Chinese President Xi Jinping meet in California. Raimondo later tells Reuters that Biden raised Boeing during the meeting. DEC. 5 - Analysts begin speculating that Boeing could deliver its first 787 Dreamliner since 2021 following a report from AAP/AIR consulting group, which mentions a scheduled Dec. 14 delivery of a Juneyao Air 787 Dreamliner. DEC. 8 - Hu Zhenjiang, deputy administrator of China's aerospace regulator, meets with Mike Fleming, Boeing's senior vice president for development programs. Hu tells Fleming that Boeing is welcome to strengthen cooperation with China's civil aviation industry. DEC. 19 - AAP/AIR consulting group report that the 787 delivery to Juneyao has been pushed to Dec. 31. The group says a second Dreamliner is being readied for China Eastern. DEC. 20 - A 737 MAX designated for China Southern Airlines flies from Boeing Field in Seattle to Boeing's nearby facility in Moses Lake, Washington and back. Analysts from Jefferies and Deutsche Bank say it appears to be a customer acceptance flight - a test flight operated by an airline pilot that occurs before delivery. DEC. 21 - Boeing delivers a 787 Dreamliner to Juneyao Airlines. It is the first Dreamliner delivery to China since 2021 and the first direct delivery to a Chinese airline since 2019. 2024 JAN. 5 - The National Transportation Safety Board says it will investigate an Alaska Airlines Boeing 737 MAX 9 flight after it made an emergency landing when a cabin panel broke off mid-flight. JAN. 6 - The FAA orders a temporary grounding of some Boeing 737 MAX 9 planes after the incident. JAN. 12 - The FAA says it will extend the grounding of the 737 MAX 9 jets indefinitely for new safety checks, announces it will tighten oversight of Boeing. JAN. 15 - Boeing says it will add further quality inspections for the 737 MAX. JAN. 16 - Boeing supplier Spirit AeroSystems says it will put in place additional inspections to its 737 fuselage production line. JAN. 16 - Boeing names a retired U.S. Navy admiral to advise the planemaker's CEO on improving quality control after 737 MAX 9 planes. JAN. 18 - India's Akasa Air announces an order for 150 737 MAX jets. JAN. 22 - The FAA recommends airlines operating Boeing 737-900ER jets to inspect door plugs to ensure they are properly secured after some operators reported unspecified issues with bolts upon inspections. JAN 23. - The European Union Aviation Safety Agency says it had adopted a U.S. safety alert calling for checks on some 737-900ER jets. JAN. 23 - Alaska Airlines CEO says he found "some loose bolts on many" 737 MAX 9s during inspections. JAN. 23 - Boeing says it will hold a quality stand down at the Seattle-area location where it makes 737 aircraft, pausing production and delivery operations for a day. JAN. 24 - Boeing delivers a 737 MAX 8 to China Southern Airlines. (Reporting by Valerie Insinna; Editing by Ben Klayman, Lisa Shumaker and Krishna Chandra Eluri)