The passenger plane involved in the Jeju Air accident declared an emergency (mayday) due to a bird strike just one minute after receiving a 'bird activity caution' warning from the control tower at Muan International Airport. It was also found that the black box recording was immediately halted.
The airport's closed-circuit television (CCTV) confirmed that the accident aircraft was in the process of go-around (ascending without landing) when it made contact with a flock of birds. Feathers and blood from a 'bar-headed goose' were found in both engines of the aircraft.
The Ministry of Land, Infrastructure and Transport's Aviation Railway Accident Investigation Committee (ARAIC) held a briefing for the families of the victims on the afternoon of the 25th at Muan International Airport to explain the progress of the investigation and future plans. This represents the first on-site investigative report regarding the Jeju Air tragedy.
The ARAIC provided detailed information about the conditions surrounding the accident aircraft before and after the black box recording was interrupted. The recording of the flight data recorder (FDR) and cockpit voice recorder (CVR) was suspended 4 minutes and 7 seconds before the aircraft collided with the azimuth facility.
The accident aircraft first communicated with the airport control tower at 8:54:43 a.m. on the 29th of last month to approach for landing. The control tower granted landing permission for runway 01. Three minutes and 7 seconds later, at 8:57:50 a.m., the control tower relayed a 'caution for bird activity (collision)' to the aircraft.
At 8:58:11 a.m., the captain and first officer discussed the presence of birds below the aircraft. Starting at 8:58:50 a.m., 39 seconds later, the recordings of both the FDR and CVR ceased simultaneously. At that time, the accident aircraft was flying at a speed of 161 knots (about 298 km) at a low altitude of 498 feet (about 151 m).
Subsequently, at 8:58:56 a.m., the pilot declared a mayday due to a bird strike while executing the go-around. This was inferred by the ARAIC through synchronizing the control tower records since no recording remains. It was determined that there were no unusual weather changes at that time.
The aircraft flew over the left side of the runway for about 4 minutes, then turned right to approach the runway for landing on runway 19. After that, it continued to roll with the body landing without the landing gear down and collided with azimuth facilities after overrunning the runway at 9:02:57 a.m.
The ARAIC confirmed the aircraft's contact with a flock of birds during the go-around through Muan Airport's CCTV. The footage does not show flames or smoke, but it can be concluded that the aircraft collided with numerous birds.
Feathers and blood from birds were found in both engines of the aircraft. After a genetic analysis commissioned to the National Institute of Biological Resources under the Ministry of Environment, it was identified as a 'bar-headed goose,' a common winter migratory bird in Korea. The ARAIC noted, 'Currently, the specimens discovered do not reveal the bird population or whether other types of birds were included, and we are planning for engine teardown inspections to check the engine condition and collect additional samples.'
The ARAIC will continue to conduct a thorough analysis of all aspects of the aircraft operation, including a detailed investigation of the wreckage, black box analysis, verification of flight records, and witness interviews. Should urgent safety measures be required during the investigation process, safety recommendations will be immediately issued to the airline and others.
However, the investigation has not clarified the aspects regarding the localizer mound and bird impacts. The ARAIC plans to study areas that require more specialized investigation and analysis through separate contracts.
The ARAIC has been collaborating with the Bureau d'Enquêtes et d'Analyses (BEA), the investigative authority for aircraft accidents in France, since the 14th. Joint investigations have also been ongoing with the National Transportation Safety Board (NTSB) since December 31 of last year.
The ARAIC completed the initial on-site investigation on the 20th and transferred wreckage, including the engine that requires detailed analysis, to the Analysis Center at Gimpo Airport in Seoul on the 21st. Additionally, a preliminary report will be submitted to the related countries and the International Civil Aviation Organization (ICAO) before the 27th, the 30th day after the accident, in accordance with the International Civil Aviation Convention. This report will also be made public on the ARAIC's website.