Month: April 2022

China Eastern Airline Aircraft
Accident Investigation & ReconstructionAviationExpert Witness

Aviation: Expert Insight On Flight MU5735 Nosedive

On March 21st, 2022, a Boeing 737 from China Eastern Airlines seating 132 passengers and crew members nosedived into the mountains of China’s Guangxi region. Lamentably, there were no survivors. CNN reported Flight MU5735 was a normal flight that departed from Kunming en route to Guangzhou in South China. The anomaly that has various aviation experts, as well as public agencies perplexed, is the plane’s nosedive position and the rate at which it situated itself into the nosedive. The accident is currently being investigated by China Eastern Airlines, the Civil Aviation Administration of China (CAAC), Boeing, CFM (engine manufacturer), and the U.S. Federal Aviation Administration. Experts.com Member and Aviation Expert, Captain Kit Darby, offers insight into this bizarre and unfortunate aircraft accident.

It is important to provide pertinent information regarding the accident before proceeding with Mr. Darby’s contribution. Airplanes usually begin to gradually descend toward their destination at 29,000 ft. Passengers are supposed to experience minimal turbulence at the stage of the flight, however, the same could not be said for Flight MU5735. According to SFGATE, “the plane’s dive appeared to have halted for about 10 seconds and it climbed briefly, adding an unusual twist to the scenario.” However, the Flightradar24 data track, which derives its information from radio transmissions, reported the plane plunged nearly 26,000 feet within a minute and 35 seconds. In general, it is difficult to place a plane into a nosedive position. Given that Flight MU5735 passed all pre-flight checks, the reality of the aircraft nosediving should not have happened. A second black box – a device that records the condition and performance of planes in midair – was found near the crash site on March 27th, 2022 (ABC7 Chicago). However, due to the mountain region’s muddy terrain, the black box was damaged with possible repair remaining questionable. Luckily, the cockpit voice recorder was located two days later and is currently being analyzed in Beijing with the help of the U.S. National Transportation Safety Board (NTSB) [Reuters]. Providing insight on the matter is Capt. Kit Darby, Aviation Expert, and Experts.com Member:

Question: How often do plane crashes occur?

Capt. Darby: Very rare. Driving a car is much more dangerous than flying in a commercial aircraft.

(Photo 1)

(Photo 2)

This was a scheduled air carrier. This is the safest group of operators by far with only .132 accidents per 100,000 flight hours.

(Photo 3)

The aircraft was at a point in the flight where it would normally start a descent for landing. It appears to have started down normally just before it began its dive.

 Question: What is the most common cause of plane incidents?

 Capt. Darby:                                              (Photo 4)

Question: According to SFGATE, it is difficult for planes to position into a nosedive, which is why this particular crash is odd. Considering the aircraft passed pre-flight checks, what would the plane have to undergo to be situated into a nosedive?

Capt. Darby: Aircrafts are what is called “dynamically stable.” If they are displaced from their normal flying state, they tend to return to their original conditions. If you nose down an aircraft, it speeds up, and the increased speed makes the plane’s nose return to its original level of condition. You would have to push the aircraft’s nose down and then hold it down to sustain a dive as speed increases.

Alternatively, something could break that forces the nose down and hold it there, but I have never seen this happen in my 24,000 hours in the aircraft and 7,000 hours teaching in simulators. Possible, but unlikely. Additionally, the hold could force the aircraft’s nose down and hold it there.

Question: ABC7 News Chicago reported the second black box from the China Eastern Boeing 737 was found. How vital are black boxes for flight investigations?

Capt. Darby: They are key. One records what the aircraft does and the other records the communications between the pilots and the air traffic controllers. Just a note that the “black boxes” are actually bright orange to help locate them in a crash. The flight recorder records 1,000 plus of the aircraft parameters. Speed, heading, altitude, flight controls, gear, flaps, time – almost everything. The plane also has voice recorders that record the radio and intercom communications.

(Photo 5)

Question: How much of the investigation is conducted by locating debris on the ground vs. reviewing the black box recording?

Capt. Darby: In a high-speed crash like this, there is very little that can be learned from the crash site due to the amount of damage done from the high sped aircraft hitting the ground at a steep angle. In this case, the crash was so extreme that the black boxes may be damaged beyond repair and therefore not a useful tool.

As of April 11th, 2022, the investigation is still ongoing. However, rumors regarding the cause of Flight MU5735’s nosedive have been circulating. Online gossip’s latest conjecture is the co-pilot might be culpable for the crash (Global Times). Since official conclusions are yet to be discovered and announced, questionable rumors are to be taken with a grain of salt. This post will be updated once the Civil Aviation Administration of China (CAAC) releases a statement.