Seoul, Dec 29
Various interpretations have emerged regarding the cause of the deadly airliner crash in South Korea's southwestern county of Muan on Sunday, with initial investigations pointing to airframe failure following a "bird strike" as the main culprit.
The exact cause remains uncertain but some analysts are already suggesting alternative reasons, including technical glitches, arguing both the engines and brakes on both sides of the plane must have failed for such a crash but that a bird strike alone could not have caused such simultaneous failures in all critical components.
The Jeju Air passenger jet carrying 181 people approached Muan International Airport, located 288 kilometers southwest of Seoul, at around 8:54 a.m, reports Yonhap news agency.
The plane declared mayday at 8:58 a.m., just one minute after the control tower at the airport issued a bird strike warning, and attempted to land going in the opposite direction of the runway at 9:00 a.m., according to the Ministry of Land, Infrastructure and Transport.
Three minutes later the aircraft crashed into a fence wall without its landing gear extended. It was unable to slow down before it reached the end of the runway, and hit the wall.
Aviation experts largely agreed that the inoperable landing gear was a direct cause of the crash.
"If you look at the video, the landing gear didn't extend, and the plane crashed with very little loss of speed," said professor Choi Kee-young from Inha University. "An airplane has multiple brakes, and if the landing gear doesn't work, the reverse-propelled engines lift the wing flaps, which act as airbrakes. But they didn't seem to have worked in this case."
Experts identified the bird strike as the most likely cause of the landing gear malfunction, as it may have affected both the engine and hydraulic system.
"If birds fly into the engine, it can damage the engine and affect the hydraulic system connected to it," said Kim Kyu-wang, director of Hanseo University Flight Education Center.
"The hydraulic system raises and lowers the landing gear during takeoff and landing, and that part may have been damaged."
However, some argue that a single engine failure following a bird strike is unlikely to cause such a catastrophic outcome.
They note that even if one engine had failed due to the bird strike, the second engine could have powered the landing gear, suggesting the possibility of additional systemic issues.
"In case of a belly landing, a plane has to slow down by creating more drag with the wings, but this was not visible in the video," professor Choi said.
"My guess is that both engines failed," he said. "If both engines fail, the whole airplane goes down and the pilot's commands can't get through."
Experts called for a thorough investigation to determine whether the crash was caused by a bird strike, an airframe defect or poor maintenance.
"We need to analyze the cause, but it's very unusual for all three landing gears to fail to deploy," said Kim In-gyu, director of the Korea Aerospace University Flight Education Center.
"It is difficult to conclude that a bird strike alone was responsible. We also need to examine whether the aircraft had any pre-existing defects.
—IANS