BEIJING — The pilots had met China’s requirements for flying a industrial jet. No issues had been discovered with the plane earlier than it took off. No harmful cargo had been loaded aboard. Communications with the airplane appeared regular till its lethal plunge.
A preliminary report released on Wednesday by China’s aviation security regulator did not dispel a lot of the thriller about why a China Eastern jet suddenly went into a nosedive in clear climate final month and crashed right into a muddy hillside, killing all 132 folks aboard. The report primarily cataloged what was beforehand recognized in regards to the crash.
“The investigation found that the flight and cabin crew onboard, as well as the maintenance and clearance personnel, met qualification requirements,” the report mentioned. “Before it deviated from cruising altitude, there was nothing abnormal in wireless communications between the crew and air control or in the control commands.”
The report additionally urged that getting extra proof from the airplane’s two flight recorders might take a while. “The two recorders on the plane were severely damaged in the crash,” it mentioned, “and data recovery and analysis is proceeding.”
As a signatory to the Convention on International Civil Aviation, China’s regulator was below an obligation to provide a preliminary report on Wednesday, 30 days after the crash. But a abstract assertion issued by the regulator, the Civil Aviation Administration of China, didn’t put ahead any theories to deal with why the airplane, a Boeing 737-800, immediately turned virtually vertical whereas cruising at 29,000 ft and maintained that place aside from a quick surge upward about two-thirds of the best way right down to the bottom.
Commercial jets are designed to be naturally steady from entrance to again whereas in flight. They don’t fly virtually straight down at very excessive pace until excessive drive is constantly utilized to the horizontal stabilizers on both facet of the tail, aviation consultants mentioned within the days after the crash.
A mechanical failure or software program error could cause the horizontal stabilizers to malfunction, or a pilot can intentionally drive the airplane to fly virtually straight down. The report didn’t deal with these potentialities. But it did point out that key parts of the tail had been discovered on the crater left by the airplane in a bamboo-swathed hillside.
The plane’s engines had been additionally discovered there.
Earlier this month, Wu Shijie, a security official from the Civil Aviation Administration of China, cautioned towards a plethora of theories in regards to the crash that had unfold on-line inside China. Some of those theories have urged pilot suicide as a reason for the crash. Chinese aviation authorities have stepped up checks on the well being and psychological well-being of economic plane pilots in latest days.
But Mr. Wu mentioned these measures for pilots shouldn’t be taken as an indication that the reason for the crash had been recognized. “We still cannot come to a conclusion on the cause and nature” of the crash, he told reporters, based on an official Chinese aviation information web site.
China has tried to point out openness and adjust to worldwide requirements for air crash investigations. It has despatched each black bins to the National Transportation Safety Board in Washington for evaluation.
The N.T.S.B. additionally despatched a group to the crash web site in southern China to assist with the investigation. China allowed the group to enter the nation with out going by way of the standard three weeks or extra of quarantine, permitting the visiting investigators to comply with as an alternative the “travel bubble” necessities used through the Beijing Winter Olympics. Those requirements name for day by day P.C.R. testing for Covid-19 and severely prohibit contact with Chinese residents. The N.T.S.B. mentioned on Wednesday that its group had returned to the United States on April 14.
Keith Bradsher reported from Beijing, and Chris Buckley from Sydney, Australia.