The timing of a bird collision, which authorities suspect may have contributed to the crash, has not yet been determined.
The black box recovered from a South Korean aircraft that crashed during landing last month stopped recording when the jet was about 1.2 miles away from the runway, according to a preliminary report released by the South Korean Transport Ministry on Monday.
The Boeing 737-800 aircraft that took off from Bangkok overshot the runway at Muan International Airport in South Korea while attempting an emergency landing on Dec. 29, 2024. The plane, operated by the South Korean airline Jeju Air, burst into flames after hitting a concrete wall at the end of the runway, killing 179 of the 181 passengers onboard. Two crew members who were seated at the tail end of the plane survived the crash.
Preliminary findings by the South Korean Transport Ministry found that the black box holding the plane’s flight data and cockpit voice recorder had stopped working approximately four minutes and seven seconds before the crash happened, local media Yonhap News Agency reported.
The report did not specify the reason behind the stoppage. Black box recorders collect data on communications involving pilots in the cockpit and how the aircraft systems perform in flight. Authorities had previously said that it would contain vital information about the lead-up to the plane crash and the crash itself.
The timing of a bird collision, which authorities suspect may have contributed to the crash, has not yet been determined as the probe remains ongoing, according to the ministry.
During a briefing with victims’ families on Saturday, the ministry said the plane contacted air traffic control at 8.54 a.m. local time on Dec. 29 before landing and was cleared to land on a runway in the opposite direction from where the crash happened, the local news agency reported.
The control tower issued a warning several minutes later to inform the pilot about bird activity. The ministry said its preliminary investigation found that the black box stopped recording shortly after the plane received the warning.
The pilot was believed to have issued a “mayday” distress call before the black box stopped recording, according to the ministry, citing records from the control tower. Authorities also found blood and feathers from a type of migratory duck on both of the plane’s engines, it said.
Surveillance footage obtained by investigators from the incident also showed that the plane struck a flock of birds during a go-around, according to the ministry.
The ministry said it plans to dismantle the engines in the next phase of the investigation to examine their components, analyze in-flight and air traffic control data, and investigate the embankment, localizers, and evidence of bird collisions.
“These all-out investigation activities aim to determine the accurate cause of the accident,” the report stated.
The ministry said it will share the report with the International Civil Aviation Organization (ICAO) and aviation authorities in Thailand, the United States, and France, which are the home states of the plane and engine manufacturers.
Under global aviation guidelines, investigators are required to issue preliminary reports to ICAO within 30 days of an aviation accident and release a final report within a year.
It remains unclear why the plane failed to deploy its landing gear. Sim Jai-dong, a former transport ministry accident investigator, said that the discovery of the missing data from the budget airline’s Boeing 737-800 jet’s crucial final minutes was surprising and suggests all power, including backup, may have been cut, which is rare.
Bird collisions that cause damage to both engines are rare, though pilots have successfully landed without fatalities in such situations, including the “Miracle on the Hudson” river landing in the United States in 2009 and a cornfield landing in Russia in 2019.
Reuters contributed to this report.