Report on last month’s China plane crash does not identify cause

China’s preliminary investigation into the country’s deadliest plane crash in about 30 years did not identify a cause, according to a report released on Wednesday.

In March, a China Eastern plane was flying between Kunming and Guangzhou when it nosedived into a mountainside, disintegrating on impact and claiming the lives of all 132 people on board.

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Two flight recorders, or “black boxes”, were recovered and are being analyzed in the United States in the hopes of unlocking the mystery behind the jet’s rapid descent.

A brief of the report released by the Civil Aviation Administration of China (CAAC) on Wednesday gave no further details on the possible reasons behind the crash.

The update came as 30 days passed since the incident -- the deadline by which China is required to submit an early report to the International Civil Aviation Organization.

Investigations found the flight and cabin crews’ qualifications “meet requirements,” and the same was said of maintenance staff, the CAAC said in a statement.

“The airworthiness certificate of the aircraft in the accident was valid,” the statement said.

There was no report of fault before the flight, nor was there cargo declared as dangerous goods on the plane, said the CAAC, noting no abnormalities in navigation and monitoring equipment.

The plane was equipped with two flight recorders: a cockpit voice recorder and a flight data tracker in the rear passenger cabin.

The devices “were severely damaged due to the impact, and data restoration and analysis work is still in progress,” said the authorities.

China Eastern previously said that the plane’s captain and two co-pilots were not under suspicion.

The aircraft went down near Wuzhou in southern China after losing contact with air traffic control.

Tracking website FlightRadar24 showed the jet sharply dropped from an altitude of 29,100 to 7,850 feet (about 8,900 to 2,400 meters) in just over a minute.

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