You may recall (or not) my posts about the curious case of China Eastern Flight MU5735 and follow ups discussing the highly unusual situation of the China Eastern Airlines B737-800 that on March 21, 2022 during a flight from Kunming to Guangzhou, China suddenly entered a near vertical dive and plunged from its cruising altitude and crashed in a matter of only a couple of minutes.

Flightradar24 reconstructed the relevant portion of the flight from ADS-B data recorded in real time.

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The cause of the incident is/was a mystery because airliners don’t just fall out of the sky and crash from such an altitude. Compounding the intrigue was the lack of communication from the flight deck during the dive and the fact that the black boxes – the flight data recorder (FDR) and cockpit voice recorder (CVR) – were damaged so badly that the data was unavailable at the time the preliminary report was required to be issued 30 days following the crash.

To get as much information, if any, as possible from the FDR and CVR the Civil Aviation Administration of China (CAAC) sent the black boxes to the manufacturer in the United States for analysis. Yesterday, the Wall Street Journal reported that data recovered so far indicates that the plunge to the ground resulted from inputs to the flight controls by someone in the cockpit, i.e. an intentional act. It appears this conclusion was based on information from the FDR. The CVR may be the best evidence of what happened on the flight deck.

The WSJ report is unofficial. The CAAC and U.S. National Transportation Board have not confirmed or denied the WSJ story. I wanted to get this information out before it became too stale.

As discussed in my original post, a deliberate crash of the aircraft seemed to be the most plausible cause given what was know at the time of the crash. I think suspicion may focus on the copilot who had over 31,000 hours of flight time. For what its worth, I believe it is highly unusual for a pilot with that much flight time not to be the pilot in command.

Final Thought

A commercial airline pilot intentionally crashing a plane is extremely rare but not unprecedented. It has happened only a handful of times in the history of commercial aviation. The most recent example I’m aware of is Germanwings Flight 9525, a 2015 flight where a pilot crashed an Airbus 320 into the French Alps.

Commercial aviation is by far the safest form of travel. Still, it is a good idea to be nice to people like your surgeon or pilot.