The accident of a Boeing 737-800 operated by China Eastern Airlines on Flight MU5735 that crashed while flying the route connecting Kunming (KMG) and Guangzhou (CAN) is still under investigation.

The preliminary accident report indicates that the aircraft took off from runway 21 at Kunming Changshui Airport at 13:16 Beijing time on March 21, 2022, climbed to its cruise altitude of 8,900 meters at 13:27, and entered Guangzhou’s control area via route A599 at 14:17. At 14:20:55, the Guangzhou control area radar detected an altitude deviation. At that moment, the aircraft had deviated from its assigned cruise altitude. The controller immediately contacted the crew but received no response. Shortly after, the radar signal disappeared.

The aircraft impacted vertically with the ground. There were no survivors.

On March 22, 2024, the Civil Aviation Administration of China (CAAC) issued a statement outlining the progress of the investigation. Firstly, the agency is conducting specialized technical investigation into various aspects of the aircraft involved in the accident. Significant wreckage, such as engine components and control system parts, are being sent to laboratories for analysis. Flight recorders (commonly known as black boxes), which were damaged, are being repaired for data analysis.

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Additionally, the investigation is assessing the condition of the crew members, their health, performance, and other personal factors. Flight plan submission, aircraft weight and balance, performance calculations, and crew preparation are also being cross-referenced. On the company’s side, training management, personnel qualifications, maintenance practices, and compliance with airworthiness directives and service bulletins are under scrutiny.

According to the CAAC, preliminary investigations have revealed that both flight and cabin crew had valid licenses and certificates, and their flight hours, rest periods, and health checks complied with regulations. The aircraft’s airworthiness certificate was valid, and maintenance personnel met the requirements. No aircraft system failures were found before takeoff. The aircraft’s load complied with regulations, with no evidence of dangerous goods.