China Eastern Airlines (CIAH) (CEA) has returned its fleet of Boeing 737-800 aircraft to commercial service less than a month after the aircraft type crashed in southern China, Chinese news agency Xinhua reported.  

As part of an emergency safety measure, China Eastern previously grounded a total of 233 Boeing 737-800s. The airline conducted system tests, structural inspections and verified airworthiness data for each aircraft before resuming passenger operations.  

On March 21, 2022, a Boeing 737-800 aircraft registered B-1791, carrying out flight MU5735 from Kunming to Guangzhou with 132 passengers on board, crashed in the Guangxi mountains, in southern China. 

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A China Eastern Airlines Boeing 737 with 132 people on board has crashed in a mountainous region of China
 

It took two days after the incident for Chinese recovery crews to find the cockpit voice recorder. The second black box, the flight data recorder, was found on March 27, 2022. According to the Civil Aviation Authority of China (CAAC), the exterior of both black boxes was severely damaged. 

On April 1, 2022, a group of seven investigators and technical advisers representing the US National Transportation Safety Board (NTSB) joined Chinese authorities to investigate the China Eastern Boeing 737-800 crash. Boeing also said that it will continue to support China Eastern, and that a technical team of the aircraft manufacturer is supporting the NTSB and the CAAC in its investigations. 

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Investigators and technical advisers of the US NTSB joined Chinese authorities in the investigation of the China Eastern MU5735 crash. 
 

According to Xinhua, a preliminary investigation report is expected to be completed within 30 days of the accident. 

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