When a terrifying accident occurred at nearly 10,000 meters, it was only the quick thinking of the well-trained flight crew that ensured everyone aboard the aircraft survived, Wang Ru reports.

It started with a bang. Then the door to the cockpit opened and the plane began to shake violently. As people started screaming, an oxygen mask dropped in front of Bi Nan's face, and the passenger cabin became dark as the power cut out.

Bi, who was working as the chief stewardess on Sichuan Airlines flight 3U8633 in May 2018, soon realized the cabin was in decompression.

In her decade of working as a stewardess, she had never faced such a situation. Sitting in the front of the passenger cabin, she could see the figure of the copilot, who was not moving at all. She knew how dangerous the situation was, but she didn't know what had happened and was half frozen by the wind rushing through the cabin.

Fortunately, the well-trained stewardess managed to stay calm. "If I am overwhelmed with panic, what will the passengers feel?" She told herself. Then, just as she had practiced hundreds of times, she told passengers to pay attention to the guidance of flight attendants, directed the attendants to assist and comfort passengers, and attempted to contact the cockpit, yet no one answered.

Bi gestured to the second captain Liang Peng, who had been in the passenger cabin, and he made his way to the cockpit to check what had happened.

Minutes before the door opened, captain Liu Chuanjian and copilot Xu Ruichen had experienced a terrifying moment as one of the front windshields had blown out suddenly, and the swift drop in pressure had sucked the upper part of Xu's body outside the plane. Luckily, thanks to his seat belt, some of his lower body was still tethered inside the aircraft. When the pressure normalized, he was pushed back to his seat by the strong wind rushing through the window.

The window blowing out set off a chain reaction. The plane shook violently as error messages filled the screens of the flight deck, and instruments began to fail.

What Liang saw when he entered the control cabin was that Liu, who had flown fighter jets when he was younger, was manually controlling the plane. Liang quickly took a seat, fastened the seat belt, applied the oxygen mask and began helping Liu navigate and contact the air traffic control. Xu, the injured copilot, after resting for a while, also managed to send out the 7700 code, signaling the flight had encountered an emergency.

It was a plateau route from Southwest China's Chongqing city to Lhasa in the Tibet autonomous region. When the accident happened, the plane was at a cruising altitude of 9,800 meters, and had arrived above the edge of the Qinghai-Tibet Plateau, with mountain ranges at an altitude of about 5,000 to 6,000 meters on average, posing a big challenge to Liu, who had to lower the altitude of the plane to overcome the oxygen shortage and ice-cold temperatures, but at the same time ensure that the plane would not collide with any of the mountains.

Normal temperature inside a plane is set at around 20 C, but after the incident, the internal temperature rapidly dropped to not far above the — 40 C it would have been at 9,800 meters. When Liang noticed Liu was gently shaking with the cold, he rubbed Liu's back to warm and encourage him.

"I was not familiar with the captains or the copilot before, but I knew we had strict standards for choosing pilots on a plateau route. There must be two captains who are both flight instructors, so I believed in their proficiency," says Bi.

"Some passengers were so nervous that they developed cramps. Stewardesses massaged and comforted them by giving assurances that we had the ability to keep them safe," she adds.

Thirty-four minutes after the windshield blew out, the plane, with 119 passengers and nine crew members, landed safely at the Chengdu Shuangliu International Airport in Sichuan province.

After landing, Bi learned what had happened, and she saw that Xu was badly injured, with his shirt and tie torn, and blood all over his face and hands.

It was a real miracle. In 1990, British Airways flight 5390 endured a similar incident where a windshield broke, leading to the captain being sucked out of the plane. That had left a deep impression on Liu. During an interview with China Media Group in 2018, he mentioned that, compared with then, flight 3U8633 was at a higher altitude, flying at a faster speed of about 800 kilometers per hour when the window broke.