(Bloomberg) — After flying at high altitudes on March 21, China Eastern Airlines Corp. flight MU5735 took off. within seconds with a nosedive, an unusual delineation that will be the focus of researchers trying to understand what brought down the Boeing Co. jet.

While most plane crashes occur during takeoff and landing, violent descent incidents such as Monday’s crash are responsible for an excessive proportion of aviation deaths as they almost inevitably kill everyone on board.

The plane from China Eastern took just 1 minute and 35 seconds to clear from the tracking sites after it began a quick and abrupt dive from 29,000 feet.

It’s too early to say what happened, said Hassan Shahidi, the president and chief executive officer of the nonprofit Flight Safety Foundation, based in Alexandria, Virginia. “In the coming days, China Eastern, the Chinese aviation regulator, Chinese researchers and Boeing will have much more information as the flight data recorder, cockpit sound recorder, air traffic data and other data become available.”

The 737-800 is part of Boeing’s Next Generation 737s, which have a solid safety record among aircraft types, with only 11 fatalities out of more than 7,000 aircraft delivered since 1997.

While the cause of Monday’s incident is still unknown, similar incidents may provide clues.

Here’s what we know about other planes that crashed in flight:

Sriwijaya flight 182, Jan 9. 2021

A 26-year-old Boeing Co. The Indonesian airline’s 737-500 jet took off from Jakarta carrying 62 people and initially flew what appeared to be a routine route. After reaching about 10,000 feet (3,050 meters), it leveled off and stayed between 10,000 and 11,000 feet for about 45 seconds.

About that time, an air traffic controller radioed the plane to say it was off course. There was no response. At about the same time, the aircraft turned about 40 degrees to the left in the opposite direction from which it was pointed. At that point, the jet began an abrupt descent before plunging into the Java Sea, killing everyone on board.

While the final investigation report is still pending, a preliminary probe found that the jet’s left engine started to reduce power while the right engine setting remained the same. Uneven thrust settings can cause an aircraft to turn if not countered properly, and there was evidence that the pilots were unable to maintain their assigned course and may have been distracted by attempts to turn to avoid a storm.

Previous crashes may provide clues to China Jet's mysterious plunge

Atlas Air Flight 3591, February 23, 2019

As the Boeing 767-300 freighter approached Houston with packages for Amazon.com Inc., a copilot accidentally added engine power. Apparently disoriented and thinking the plane’s nose was dangerously high, he then pushed the plane into a steep dive, according to the NTSB.

The jet reached speeds of 805 kilometers per hour in seconds, crashed into a swamp in Trinity Bay and killed the three people on board.

However, the Atlas jet was much lower than the China Eastern flight when it rolled over, and the dive was shorter.

Previous crashes may provide clues to China Jet's mysterious plunge

A Flydubai crash in Rostov-on-Don, Russia, on March 19, 2016, was the result of a similar pilot disorientation to the Atlas Air flight, causing the 737-800 to plunge from an altitude of about 4,000 feet, according to Russia’s Air. Accident Investigation Commission. All 62 people on board died.

Pressing the wrong button in the cockpit can cause similar disorientation and accidental dives.

In September 2011, a Boeing 737-700 owned by Air Nippon Co., the predecessor of All Nippon Airways Co., plunged approximately 6,000 feet from a cruising altitude of 41,000 feet after one of its pilots was suspected of inadvertently operating the rudder trim control as you try to change a cockpit door lock to allow the captain to re-enter the cockpit. The incident did not result in a crash or any damage to the aircraft.

Silk Air Flight 185, December 19, 1997

This 737-300 with 104 people on board mysteriously dove from 35,000 feet into a river near Palembang, Indonesia, after both crash-proof recorders were disabled.

The US National Transportation Safety Board, or NTSB, which had assisted the Indonesian National Transportation Safety Committee in its investigation of the crash, concluded that the pilot-in-command had deliberately brought down the plane. Indonesian investigators said there was not enough evidence to identify what happened.

The plane dived so fast — close to the speed of sound — that it began to fall apart, researchers said.

USAair Flight 427, September 8, 1994

This was the second of two accidents attributed to a fault in the rudder of the 737. All 132 people on board were killed in the crash near Pittsburgh.

As the plane, a 737-300, approached to land at an altitude of about 6,000 feet, the rudder jammed to one side, the NTSB concluded. The plane rolled sharply to the left and its nose pointed to the ground.

Several years after the accident, the US Federal Aviation Administration, or FAA, ordered a rudder correction for all 737s. Since then, no more accidents have been attributed to the system.

Air France Flight 447, June 1, 2009

An Airbus SE A330 flying 228 people from Brazil to France plunged into the Atlantic Ocean from a cruising altitude above 30,000 feet.

The instruments used to determine airspeed malfunctioned after ice formed on them, and the pilots became disoriented, climbed and allowed the plane to slow down dangerously and enter an aerodynamic shed, French researchers found. All on board died. The flight data recorders were discovered after a long search at the bottom of the ocean.

Previous crashes may provide clues to China Jet's mysterious plunge

The Air France A330 jet rocked back and forth instead of diving, falling at an average of about 11,000 feet per minute, according to the study.

Malaysia Airlines Flight 370, March 8, 2014

Arguably one of the greatest mysteries in civil aviation, the Boeing 777-200 with 239 people on board disappeared en route from Kuala Lumpur to Beijing about 40 minutes into the flight. After three years, the search for the plane was discontinued and some of the wreckage eventually washed up on shores thousands of miles away.

While the cause of the disappearance has not been determined to date, the Australian Transport Safety Bureau said in a November 2016 report that data and debris indicate the plane plunged into the sea with no one in control after it lost its last satellite communications. had made.

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