China Eastern flight MU5375 plunged from a cruising altitude of 29,000 feet into a mountainside, killing all 132 people on board while travelling from Kunming to Guangzhou on March 21.
It was China's deadliest air disaster in about 30 years.
WSJ reported that U.S. officials’ preliminary assessment of what led to the accident was based on data from a black box recovered in the crash.
The data suggested inputs to the controls pushed the plane into a fatal nosedive.
It could have been caused by a pilot or someone who had forced their way into the cockpit of the Boeing 737-800, WSJ reported.
“The plane did what it was told to do by someone in the cockpit,” a person who is familiar with American officials’ preliminary assessment said.
The preliminary assessment includes an analysis of information extracted from the plane’s damaged flight-data recorder.
U.S. officials believe their conclusion is sound as Chinese investigators have not indicated any problems with the aircraft or flight controls so far.
Any issues that could have caused the crash would need to be addressed in future flights, it was reported.
However, one person familiar with the U.S. officials’ preliminary assessment said the Americans do not have all information available to their Chinese counterparts, WSJ added.
China investigators still investigating
China's Civil Aviation Administration (CAAC) said in April that investigators found no evidence of "anything abnormal", according to a report from Boeing.
WSJ also reported that the Boeing 737-800 model is "a workhorse of the global aviation industry" and one of the Boeing aircrafts with "the best safety records in commercial flying".
The next step, WSJ reported, was for U.S. officials involved with the investigation to turn their attention to the actions of a pilot.
China Eastern issued a statement to WSJ saying that no evidence has emerged that could determine whether or not there were any problems with the aircraft involved in the accident.
The airline also repeated its senior official’s statement from March that the pilots’ health and family conditions were good, and that their financial status was in good shape.
The airline said it was not responsible for the accident investigation and referred to official announcements.
This included the Chinese government’s summary of its preliminary report released on April 20.
The summary said data restoration and analysis of the damaged black boxes was still in progress.
“Any unofficial speculation may interfere with the accident investigation and affect the real progress of the global air transport industry,” the airline said.
Information on crash scrubbed
AFP reported that China's ruling Communist Party moved quickly to control information and revved up its censorship machine in the immediate aftermath of the crash, even with media outlets and local residents racing to the crash site.
Authorities swiftly cordoned off a huge area and China's internet regulator announced it had scrubbed vast amounts of "illegal information" on the crash from China's internet, AFP reported.
The CCP has reportedly maintained its tight grip over the narrative, with the preliminary probe leaving key questions unanswered, AFP added.
Top photo via Xinhua