On the twenty first of March 2022, a Boeing 737 passenger airliner crashed right into a mountain. This was China Jap Airways flight 5735 flying from Kunming to Guangzhou within the Individuals’s Republic of China. All 132 souls on board perished within the crash.
This was the primary deadly crash of a Chinese language mainline service in almost twelve years. China’s business aviation security report had been one of many strongest on the earth.
The plane, a Boeing 737-89P registered in China as B-1791, was not but seven years previous and up-to-date on upkeep. The flight departed barely late from Kunming Changshui Worldwide Airport at 13:16 native time for a two-hour flight. The climate was cloudy however visibility was good.
There have been three pilots on the flight deck. The captain had 6,709 flight hours. The pilot listed as the primary officer with 31,769 flight hours was one of the skilled pilots at China Jap Airways, the place he was a flight teacher/captain. The pilot listed because the second officer had solely 556 hours flight time; China Jap Airways confirmed he was there for remark, with a view to construct up expertise.
We do not know who was on the controls.
The plane was cruising at 29,100 toes and entered the management zone of Guangzhou at this altitude at 14:17.
Three minutes later, at 14:20, air visitors controllers seen that China Jap Airways flight 5735 was descending quickly. They instantly tried to contact the flight crew. There was no reply.
Flightradar24’s playback of the flight primarily based on ADS-B knowledge confirmed the sudden descent as beginning at 06:20 UTC (14:20 native): the Boeing appeared to plunge from 29,125 toes to 7,426 toes above imply sea degree. The subsequent replace confirmed a short restoration to eight,600 toes earlier than descending once more. The ultimate replace exhibits the plane at 6,525 toes, 4,375 toes and, lastly, 3,225 toes earlier than the flight disappeared. The descent passed off over three minutes.
China Aviation Evaluate confirmed the next footage of the crash: the primary is alleged to be CCTV footage from a neighborhood mining operation, the second is dashcam footage with no attribution.
Sprint cam footage pic.twitter.com/w8iOzHblXE
— ChinaAviationReview (@ChinaAvReview) March 21, 2022
The Boeing 737 crashed into mountainous terrain close to Wuzhou in Guangxi. Native residents heard a loud explosion and reported an enormous bamboo hearth within the space. Native firefighters arrived at 15:05 with extra being dispatched from outdoors the world at 16:40. The fireplace was lastly extinguished at 17:25.
There have been no survivors.
Because the crash passed off within the Individuals’s Republic of China, the investigation falls to the Civil Aviation Administration of China (CAAC). The NTSB participated because the accredited consultant of the state of design and manufacture (the US), with technical advisers from Boeing, the FAA, and engine-maker CFM. In observe this meant that when CAAC’s personal makes an attempt to obtain the badly broken flight recorders bumped into hassle, the storage modules have been labored on collectively at CAAC’s Beijing laboratory and on the NTSB’s recorder lab in Washington, with CAAC engineers and NTSB engineers named as a joint crew.
From Ruibao Information:
NTSB engineers landed on a key prognosis — the stutters, echoes, and digital noise within the first CVR obtain weren’t issues with the audio itself. The chip’s inner “deal with traces” have been damaged. By the use of analogy: the magnetic tape was nonetheless there, however the index that informed the playback machine which order to learn it in had been torn up. NTSB rebuilt the connector — pulled off the housing, insulated with Kapton tape, reshaped the bent pins one after the other — and pulled the information once more. All 4 channels (captain, first officer, observer, cockpit space mic) got here again at “wonderful” high quality. The trail from “fully unintelligible” to “wonderful” was a crew of engineers at a microscope workstation, straightening bent pins one after the other.
The NTSB transferred the extracted knowledge from all 4 CVR audio channels (rated “Glorious”) and produced a Cockpit Voice and Flight Information Recorder Mixed Obtain Report, dated 1 July 2022. This was a factual report describing what was on the recorders, the way it was recovered, and what situation the information was in. NTSB then handed every part from the CVR to CAAC and, as is regular observe, retained no copies of the audio. Nevertheless, they did preserve their FDR working information, on the premise that these can be wanted to assist CAAC in assembling the ultimate report.
That ultimate report has by no means appeared.
The CAAC issued their preliminary 30-day report in Chinese language in April 2022 and an interim report in March 2023, which concluded solely that the investigation was persevering with as a result of the accident was “very sophisticated and very uncommon”. The 2-year replace in March 2024 was extra substantive, stating that the preflight {qualifications} of the crew, upkeep employees, airport assist employees and air visitors controllers had all been in step with necessities, that there had been no abnormality in radio communications earlier than the crash, no harmful climate on the crash web site, and no proof of harmful items within the cargo or baggage.
What CAAC haven’t stated, in any replace, is what they suppose occurred.
The third anniversary in March 2025 got here and went with none replace in any respect, as did the fourth in March 2026. In Might 2025, when a Chinese language citizen filed an open-government info request asking for the investigation progress report, CAAC refused, citing dangers to “nationwide safety and social stability.”
In January 2026, a Chinese language citizen filed a Freedom of Data Act request with the NTSB, asking for the company’s information on the investigation. The NTSB responded on 29 April 2026 with the recorder report and supporting supplies. The requester posted them to GitHub and Wikimedia Commons.
On 1 Might, the NTSB additionally printed the recorder report to their FOIA Studying Room, confirming the paperwork as genuine.
Inside that recorder report is that this key sentence: whereas cruising at 29,000 toes, the gas switches on each engines moved from the run place to the cutoff place. (bolding mine)
The 2 switches sit side-by-side on the throttle quadrant and could be operated by one hand on the Boeing 737NG. The report confirms that each engines spooled down and the autopilot disengaged. Determine 12 and 13 present the ultimate 90 seconds of recording, which even with out NTSB evaluation look fairly damning.
Determine 12 plots the ultimate 90 seconds of FDR knowledge. For the primary 60 seconds the plane is in cruise and the traces are flat. Then, within the ultimate 30 seconds, each elevators deflect considerably downward and each management columns are pushed ahead — a sustained nose-down command from the cockpit. Each management wheels swing wildly throughout a variety, oscillating by means of the descent, with the ailerons mirroring these inputs. The rudder stays largely impartial till a pointy deflection on the very finish. Strain altitude drops from 30,000 to about 25,000 toes over the seen window, and airspeed climbs sharply because the recording ends.
Please observe that none of that is acknowledged within the NTSB report; the one proof for a nose-down command exists within the pictures of the FDR outcomes. We have no idea the circumstances within the flight deck. The NTSB textual content focuses on the FDR recording which terminated in lower than half a minute after the gas switches moved to CUTOFF:
The information stopped with the plane in a descent at roughly 26,000 ft. It didn’t seize the rest of the descent and ultimate accident sequence. Investigating the explanation for the untimely finish of the flight knowledge it was discovered that whereas at cruise at 29,000 ft, each engine N2 values decreased quickly under the purpose at which the turbines drop offline. The FDR doesn’t have a battery backup, so with out energy from the plane turbines it would energy down. That is completely different from the CVR, which does have a battery backup and might proceed recording for no less than 10 minutes after the lack of the plane turbines. Wanting given that the engine N2 dropped under the generator cutoff pace, it was discovered that whereas cruising at 29,000 ft, the gas switches on each engines moved from the run place to the cutoff place. Engine speeds decreased after the gas swap motion.
The report doesn’t analyse the extracted knowledge or put ahead a possible trigger.
Within the speedy aftermath of the crash, a preferred conspiracy principle on Chinese language social media was that the crash was a murder-suicide carried out by the captain, and that the extremely skilled first officer (rumored to be his former teacher) was powerless to cease it.
The CAAC has denied the speculation wholesale with out providing any various clarification.
Nevertheless, primarily based on the FOIA launched doc, it actually appears that an individual on the flight deck intentionally reduce off the engines and that apart from a really transient restoration in the beginning, no pilot was profitable in pulling the plane out of the dive.
As of writing, the CAAC have made no public remark. CNN confirmed that they reached out to CAAC and to China Jap however acquired no response. State media has not addressed the FOIA launch. To be honest, the information broke in the course of the Might Day vacation interval, however silence on this story is hardly new.
It’s nagging at me {that a} pilot reducing off the gas seems as a consequential cockpit concern in 4 of the latest circumstances that we’ve mentioned or that I’m within the means of writing about (Transair 810 (July 2021), China Jap Airways flight 5735 (March 2022), Air India 171 (June 2025) and Jeju Air 7C2216 (Dec 2024)).
