The flight recorder of the Jeju Air plane that crashed last month, killing 179 people, has stopped recording the last four minutes, South Korean authorities said Saturday, in a major setback for investigators.
The data extracted from the so-called black box, which consists of the cockpit voice recorder and flight data recorder, is generally of great importance in the investigation of aviation accidents. South Korean officials working with the U.S. National Transportation Safety Board said the plane's last four minutes of flight data would be particularly important in the incident.
But on Saturday, South Korea's Ministry of Land, Infrastructure, Transport and Tourism announced that the Boeing 737-800's black box had stopped recording at the time for reasons that have not yet been identified.
“We will investigate why the data was not recorded,” the ministry said in a news release. It also said other data and analysis will be used to understand what happened during last month's disaster.
Jeju Air Flight 7C2216, which came from Bangkok with 181 people on board, was preparing to land at Muan International Airport in southwestern South Korea at 8:59 a.m. on December 29 when the pilot shouted, “Mayday, mayday.'' “Mayday” was announced. According to officials, “bird strike, bird strike.” The pilot also told the control tower that he was “circling,” meaning he was aborting the first landing and circling in the air to prepare for a second landing.
However, it seems that there wasn't enough time to go around. Instead, the plane entered the runway from the opposite direction and landed belly-first without deploying its landing gear. It appears that the plane was unable to control its speed and overshot the runway. Four minutes after the Mayday emergency call, the plane crashed into a concrete structure from the south end of the runway, bursting into flames.
The key question is: What happened during those four minutes?
“Black box data is extremely important in the investigation,” said Hwang Ho-won, chairman of the Korea Aviation Security Association. “If investigators don’t have that, it creates serious problems for investigators.”
The crash is further shrouded in mystery due to missing data, but it is the deadliest domestic air disaster in South Korea and one of the world's worst since Lion Air Flight 610 in 2018, when all 189 people on board were killed. It had the worst death toll.
Huang said black boxes can be damaged by shock, fire or prolonged exposure to deep water. However, he said it was difficult to explain how Jeju Air's black box failed to record the last four minutes.
He said investigators may be able to reconstruct some of the cockpit conversations based on interviews with control tower personnel. Radar and other data suggested the plane attempted to gain altitude but failed and made a hasty landing after reporting the bird strike, Huang said.
Investigators said they were looking into a variety of possibilities, including the possibility that the plane lost use of one or both engines in the final minutes.
Most of the 179 people who died were South Koreans returning from a Christmas holiday in Thailand. The two survivors, both crew members, were found with injuries to the tail of the aircraft.
The disaster sparked an outpouring of national grief, with memorials erected across South Korea, but the country was also in the midst of a political crisis caused by President Yun Seok-Yeong's brief imposition of martial law and impeachment by Congress. It was also in the midst of dealing with a crisis.
