A Shenzhen Airlines passenger plane landed safely at Shenzhen Bao’an International Airport yesterday after descending by more than 5,500 meters. All crew members and passengers are safe.

Flight ZH9209 from Shenzhen to Xi’an, capital of Northwest China’s Shaanxi Province, experienced a plunge from 9,297 meters to 3,733 meters in five minutes after takeoff, but safely returned to the airport, Shenzhen Airlines said.

According to a statement issued by the airlines on its official microblog, the flight took off at 7:32 a.m. and at 7:57 a.m., when it climbed to 9,297 meters, the indicator showed air pressure was abnormal and its transponder issued code 7700, an emergency alert, to nearby control towers. The company said the emergency was caused by a mechanical failure.

The crew dealt with the alert in accordance with regulations and piloted the airplane in a 5,500-meter descent in five minutes to a safe level, or 1,100 meters in every minute, and returned to the Shenzhen airport at 9:13 a.m.

While in flight, transponder code changed from 7700 to a normal code, indicating that the emergency situation of the aircraft had been controlled.

Passengers were arranged for another flight that arrived in Xi’an at 2:19 p.m.

The incident drew the attention of the Chinese public following some reports that claimed the plane dropped 6,000 meters in two minutes.

Chen Jianguo, an experienced pilot of the airlines, said on his microblog that the earlier reports were inaccurate.

The plane descended about 5,500 meters in five minutes. The situation was not as some media had described — that it lost height and plummeted 6,000 meters in two minutes.

“A plane would disintegrate at such a speed,” Chen said.