Pilots of doomed China Eastern flight 5735 failed to respond to multiple calls after tipping into nosedive

Plane disappeared from radar screens at 2:23pm local time, three minutes after it first nosedived

Pilots of the Eastern Airlines Boeing 737-800 flight that crashed after a steep nosedive failed to respond to China’s air traffic controllers despite repeated calls being made, including after the plane’s altitude started to dip rapidly.

Flight MU5735 crashed from an altitude of almost 29,000ft into a mountainous and forested area in southern China’s Guangxi province where it caught fire on Monday.

The plane, carrying 132 people including flight crew, was flying from Kunming, the capital of Yunnan province to Guangzhou in Guangdong province.

An official from China’s air traffic controllers said at a press conference, the government’s first official briefing on the crash, on Tuesday that the Boeing 737-800 plane had disappeared from radar screens at around 2.23pm local time.

Zhu Tao, director of aviation safety at the Civil Aviation Administration of China (CAAC), said at the conference that no survivors had been found at the crash site.

He said the “jet was seriously damaged during the crash and investigations will face a very high level of difficulty.”

A search team on Wednesday found one of the black boxes from the flight in a severely damaged condition. The black box is so damaged that officials are yet to determine whether it is the plane’s flight data recorder or the cockpit voice recorder.

Flightradar24, an air traffic monitoring service, had earlier said on its blog that the Eastern Airlines plane was cruising at an altitude of 29,100 feet when it went into a high-speed dive at 2.20pm on 21 March.

The aircraft rapidly descended to 7,425ft before recovering to 8,600ft and then rapidly descending again.

In its blog, Flightradar24 mentioned the data indicated that the aircraft descended rapidly again. It said that the last message received by Flightradar24 from MU5735 was at an altitude of 3,225 ft on 2.22pm local time.

Mr Zhu said the plane disappeared from radar screens at 2:23pm local time — three minutes after it first nosedived.

He also said that “given the information currently available, we still do not have a clear assessment of the cause for the crash” and added that the aircraft did not respond to repeated calls from air controllers during its rapid descent.

At the news briefing on Tuesday, Sun Shiying, a China Eastern Airlines official, said the plane “met airworthiness standards before taking off and technical conditions were stable. The crew members were in good health, and their flying experience was in line with regulatory requirements.”

The rescue and search operation was temporarily halted on Wednesday due to the rain after hundreds of rescuers combed through the heavily forested region in southern China on Tuesday.

The cause of the crash is under investigation.