By Sophie Hu — Correspondent

Chinese authorities have officially confirmed the deaths of all 132 passengers on board China Eastern Airlines flight 5735 after the plane plunged 29,000 feet and crashed in southern China. 

On Monday, March 21, a Boeing Co. 737-800 NG flown by China Eastern Airlines took off from Kunming for Guangzhou at 3:15 am EST. It continued its normal path for the first hour of its journey, according to Zhu Tao, the director of aviation safety of the Civil Aviation Administration of China (CAAC). 

The CAAC reported that it first lost contact when the plane flew over the city of Wuzhou while the aircraft was cruising at an altitude of 29,100 feet. At 2:20 p.m., “the Boeing 737-800 aircraft started to lose altitude very fast,” tweeted Flightradar24, a service that tracks and reports flight information. In a little over a minute, the plane plunged 21,000 feet. Then, it suddenly regained altitude around 8,000 feet for 10 seconds and then crashed into a mountain valley. 

The cause of the crash still remains a mystery. 

737-800s are believed to be the safest and most aircraft available and make up about 17 percent of all passenger planes worldwide. 

The plane had flown through “not dangerous” weather, said Mao Yanfeng, head of the aircraft investigation of the CAAC.

The China Eastern pilots were highly experienced aviation veterans. The pilot of the flight had over 6,000 hours of flying experience, the first officer had nearly 32,000 hours, and the second officer, who was observing to build up experience, had about 560 hours. Combined, the men had more than 39,000 hours of flight time, nearly four and a half years of nonstop flight.

The plane crashed while it was cruising, which is rare. According to data from the National Transportation Safety Board (NTSB), less than 15 percent of all crashes happen during the cruise stage. “Usually the plane is on autopilot during [the] cruise stage so it is very hard to fathom what happened,” said Li Xiaojin, a Chinese aviation expert. 

Since the crash, rescuers have found the airplane’s two black boxes, which may assist in the investigation. The first type of black box, the cockpit voice recorder (CVR), records the sounds in the cockpit, which includes the pilots’ conversations. The flight data recorder (FDR) records every input made in the previous 24 hours. Together, the CVR and FDR document the aircraft’s flight history, which is often vital in determining the causes of a plane crash. 

The crash, the most fatal Chinese aviation incident in almost 30 years, stunned the world. 

“It’s really shocking just because of the speed of the crash and the sheer amount of deaths. I can’t imagine how terrifying it must have been for the passengers,” said freshman Lana Luo.

 “It’s just really bewildering because of how many questions there are around the crash,” she added. 

“It’s so painful,” the father of one of the victims told Reuters. “I prayed and put my daughter’s name there [the crash site]. It happened to be her birthday that same day…so I said: ‘Dad came to see you, my child. Happy birthday.'”

“We have nothing but grief now…We are living in grief every day,” he continued.