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US safety board releases new findings on fatal China Eastern flight
The US National Transportation Safety Board (NTSB) has revealed that fuel supply to both engines of China Eastern Airlines flight MU5735 was deliberately severed mid-flight before the plane plunged into a hillside in southern China, killing all 132 passengers and crew.
Key evidence from flight data recorder
According to NTSB data obtained under the Freedom of Information Act, the fuel control switches on both engines were moved to the "cut-off" position while the Boeing 737-800 was cruising at 8,839 meters (29,000 feet). The report states that engine speeds began to drop immediately after the switches were toggled.
Fuel switches regulate the flow of fuel into aircraft engines and are typically used by pilots during engine start-up or shutdown procedures.
Rapid descent captured by flight trackers
The aircraft, en route from Kunming to Guangzhou on March 21, 2022, had been airborne for over an hour when it suddenly nosedived from its cruising altitude. FlightRadar24 data shows the plane descended from 9,000 meters to 2,766 meters (9,075 feet) in just two minutes and fifteen seconds. The final recorded altitude was 983 meters (3,225 feet) at 14:22 local time.
Air traffic controllers repeatedly attempted to contact the flight during its descent but received no response, according to Zhu Tao, director of aviation safety at China's Civil Aviation Administration (CAA).
Investigation led by China, with US involvement
As the crash occurred in China and involved a Chinese carrier, the CAA took the lead in the investigation. The NTSB, however, participated due to the aircraft's US design and manufacturing origins. Investigators initially considered multiple potential causes, including pilot error, mechanical failure, structural issues, or deliberate action.
The CAA previously stated that the flight crew held valid licenses, had sufficient rest, and passed pre-flight health checks. The agency also denied earlier speculation that the crash resulted from pilot suicide, calling such rumors "misleading" and disruptive to the investigation.
China cites national security in withholding final report
Nearly two years after the disaster-China's deadliest aviation accident in decades-no final report has been released. The CAA has argued that disclosing details could "endanger national security and social stability." This stance has drawn criticism from international aviation experts and families of the victims.
While air travel safety in China has improved significantly in recent years, the lack of transparency in this case has raised concerns about regulatory accountability.
Next steps
The NTSB's findings add weight to the theory that the crash was intentional, though no definitive conclusion has been reached. The CAA has not indicated when-or if-it will release a comprehensive report on the incident.
