Traces and debris of a Jeju Air passenger aircraft, which crashed during an attempted belly landing on Sunday, remain on the runway of Muan International Airport the following day. Yonhap

It was confirmed that the government shortened the runway at Muan International Airport from 2,800 meters to 2,500 meters because the end safety area failed to meet regulatory standards during a runway extension project.

The reduced portion of the runway was designated as an end safety area instead. Authorities plan to investigate how the shortened runway may have impacted the belly landing of Jeju Air flight 7C2216, which resulted in an explosion that claimed 179 lives, leaving only two survivors.

According to an exclusive report by the Hankook Ilbo on Tuesday, the Ministry of Land, Infrastructure and Transport and the Busan Regional Office of Aviation — responsible for overseeing Muan International Airport — held a meeting in May to address the runway extension project.

The discussion focused on the reduced end safety area caused by the construction. End safety areas serve as buffer zones beyond the runway's end points to mitigate risks if an aircraft overruns the runway during landing.

The current end safety areas at Muan International Airport measure 199 meters at both the north and south ends of the runway involved in the tragic accident. The extension project aims to extend the northern section of the runway by 360 meters.

However, construction plans made it impossible to use the existing end safety area, or the northern touchdown zone, as it would have disrupted airport operations. To resolve this, the transport ministry decided to shorten the runway by 300 meters and designate the freed-up section as the new end safety area.

Starting last month, the northern end of the runway was moved 300 meters inward, with the outer section repurposed as an end safety area.

A report titled "Results of Change Management in Air Traffic Control for Muan Airport Runway Extension" by the Busan Regional Office of Aviation detailed this decision.

According to the report, the task force held deliberations for a month and concluded that adjustments to airport infrastructure standards would be managed by the relevant authority rather than the contractor.

A localizer near the runway of Muan International Airport remains damaged on Monday after being struck by a Jeju Air passenger aircraft the previous day. The localizer, an antenna that assists with runway approaches, is mounted on a concrete base on top of a small mound. Yonhap

Shortened runway raises operational concerns

As a result of the changes, the runway available for aircraft landings became shorter than before. In fact, the Busan Regional Office of Aviation specified in its report that the declared distance had been reduced compared to the original.

The declared distance refers to the runway length suitable for aircraft takeoffs and landings, including the portion of the runway appropriate for ground roll after landing.

The report stated, "The reduction in declared runway distance is considered to maintain airport operations at a level deemed acceptable in terms of safety," while also noting, "However, once the construction methods are finalized, it will be necessary to revise the reduced declared runway distance accordingly."

This indicates that during the runway construction period, the declared distance should be reduced and disclosed to ensure that airlines using Muan International Airport are aware of the changes.

During the accident, the Jeju Air plane belly-landed from north to south on the runway, which had replaced the original runway with the end safety area.

After touchdown, it skidded across the runway and the southern end safety area at speeds exceeding 200 kilometers per hour before crashing into a concrete structure housing the localizer (a navigational aid), resulting in an explosion.

In response to a question the previous day about the touchdown point, the ministry said, "The aircraft appears to have landed approximately one-third of the way down the runway, about 1,200 meters from the starting point."

With the original runway length of 2,800 meters, this would align with the one-third point; however, with the shortened length of 2,500 meters, the touchdown point effectively shifts to the midpoint of the runway.

Broader implications

The Central Accident Investigation Headquarters pointed out that Yangyang International Airport, which has a runway length of approximately 2,500 meters, accommodates similar aircraft without issues.

However, it emphasized that all possible factors, including the reduced declared distance, will be considered in the investigation.

An official from the investigation headquarters said, "The investigation will examine multiple potential causes of the accident, including the impact of the shortened declared distance."

They also noted that combining construction and airport operations is generally considered safe if no significant risks are identified.

This photo shows the Jeju Air aircraft making a belly landing on the runway of Muan International Airport, Sunday. Yonhap

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