Investigators from a joint task force work to retrieve an engine buried in the localizer mound at the site of the Jeju Air accident at Muan International Airport in Muan County, South Jeolla Province, Thursday. Yonhap

A pilot with seven years of experience at Muan International Airport testified that he had never been informed about the existence of a concrete mound housing a localizer (instrument landing system) on the runway, nor had he been able to distinguish it from a dirt pile.

The concrete structure is believed to have significantly exacerbated the accident's severity, as the aircraft's collision with the solid mound during its belly landing is thought to have triggered the catastrophic explosion.

The pilot and flight instructor, who has used Muan Airport for seven years, told Yonhap News on Thursday, "I've seen the mound from the air during countless takeoffs and landings and assumed it was a dirt pile. It never occurred to me that it was made of concrete."

He said, "There was no indication in the airport charts or separate guidance mentioning that the mound was a 2-meter-high, 4-meter-thick concrete structure. Other pilots were also unaware of its true nature."

He also addressed the bird strike issue, which has been suggested as a possible cause of the accident.

He said pilots regularly monitor bird activity using the Airport Terminal Information Service. "In my experience, bird strikes happen roughly once a year, typically affecting the wings. We always check weather conditions via frequency transmissions, and Muan airport has been issuing daily bird activity advisories lately, with air traffic controllers notifying us if birds are on the runway," he said.

Officials from the U.S. National Transportation Safety Board and a joint South Korea-U.S. investigation team inspect the wreckage and the localizer mound at the site of the Jeju Air accident at Muan International Airport in Muan County, South Jeolla Province, Tuesday. Yonhap

The Jeju Air accident occurred last Sunday at 8:57 a.m. The control tower had issued a bird strike warning just before the aircraft attempted a belly landing. During the landing, the aircraft collided with the localizer's concrete mound, leading to an explosion. The crash resulted in the deaths of 179 passengers and injuries to two crew members.

This article from the Hankook Ilbo, the sister publication of The Korea Times, is translated by a generative AI system and edited by The Korea Times.