South Korean investigative authorities have confirmed that the traces of bird strikes have been found on both engines, Jeju Airlines Boeing 737-800, involved in a landing fatal accident at the Turning Airport.
The survey has shown that feathers and other debris are based on Baikar Kogamo, a type of duck from East Asia, usually 400 g.
The provisional survey results will be announced on January 27, but the Ministry of Transport said the first details of the crash on December 29, which was obtained in the survey.
Three minutes after contacting the controller, the controller gave a landing permit on the runway 01, but the crew was warned of bird activities.
Immediately afterwards, the pilots say that there are birds under the aircraft, and about 40 seconds later, the cockpit audio recorder and flight data recorder said that they stopped at the same time.
At this point, the altitude of the aircraft was less than 500 feet and flew at 161 knots.
The crew started making a mistake and declared an emergency to the tower due to bird collisions.
While returning, the aircraft flew on the left side of the runway. The crew did not return to the circuit, but made a right turn to land on the opposite runway 19.
According to the ministry, the aircraft entered the runway “straight”, but landed without landing.
He overrun after touchdown, and collided with a localizer antenna mount four minutes after the call of “May Day”. With this impact, the aircraft broke, and only two of the 181 crew members survived.
According to the ministry, the airport surveillance camera captures the contact with birds, and the investigators have found blood and feathers from both CFM International CFM56 engines. The body was gene analysis.
The ministry said, “It is not possible to judge the number of birds and whether it contains other types of birds (in the body),” and added that it will disassemble the engine for further inspections.
In the survey, the cause of the crash must be elucidated without the complete information from the flight recorder, which has stopped operating for the last 4 minutes 7 seconds of the accident sequence.
A thorough inspection of the debris transferred to the soldering hangar will be conducted, and a detailed analysis of a specific debris held at Kanaura Airport will be performed.
The data obtained from the flight recorder is synchronized with empty area communication and other information to confirm the operation status of 737 aircraft and determine the degree of external impacts and abnormalities on aircraft and engine.
The ministry has stated that “it will require detailed analysis and verification for several months.”
Investigators need to explain some aspects of the accident, including the important decision of attempts to land in opposite direction.
If both engines are confirmed to have a bird debris, the loss of thrust may be shown, and as a result, the rising will be restricted, even the altitude will not be possible, will the crew to return to the crew urgently? You will be forced to choose if there is a possibility that the surrounding waters may arrive.
The opposite landing can lead to the danger of a tailwind and rising ground speed, but according to the ministry's manual, the assumption was exposed to the crosswind from the east.
The ministry has not disclosed the details of the altitude and speed that the aircraft achieved during a go -around.
At the same time, the suspension of the recorder indicates the loss of power generated by the engine, but it has not been confirmed yet, but it is not known whether the aircraft has lost some hydropower.
Prior to the bird's collision, the aircraft should have expanded the flap, deployed landing devices and entered. In the normal reinstatement procedure, it is necessary to establish a reliable rise, raise the landing device, and store flaps gradually.
However, the aircraft does not develop a landing device when entering the runway 19, and seems to have a flap. This survey has not yet shown the reason for these observations, and whether it is the result of the crew's behavior (whether or not), or because of the system failure.
The length of the runway 19 of the service is about 2,800 meters. The accurate distance along the runway and the speed of the aircraft at the time of landing are one of the details that have not been confirmed yet.