[From the Launch Pad] The Man Who Permits Nuri's "Ground Zero": 24 Hours with Director Park Jongchan

Enduring One More Delay at 1:13 AM
Letting Go of Nuri After a Tense Night

Editor's NoteThis report was reconstructed after the launch, reflecting actual events and confirmed facts, based on prior interviews and pre-launch input from the launch pad operations team and on-site engineers.

In the early hours of November 26, a cold wind swept through Naro Space Center, where the sea fog had not yet fully lifted. Although there were still many hours left until the scheduled 1:00 AM launch of the fourth Nuri rocket, the launch pad was already quietly awake with the tension of "launch day."

18 hours before launch. Park Jongchan, Director of the Korea Aerospace Research Institute's Korea Launch Vehicle Advancement Project, stood in front of his accommodation, briefly looking up at the sky to steady his mind. He said, "The launch pad does not allow a single excuse," describing the day as "a time when you hope the equipment will give you the right answer."

In the early hours of the 27th, after the successful fourth launch of the Nuriho rocket, Park Jongchan, Director (center among those standing) at the Naro Space Center Launch Mission Control Center (MDC), is sharing joy with his colleagues. Provided by Korea Aerospace Research Institute

"The launch pad does not allow a single excuse"

Director Park's accommodation is located in the research building inside Naro Space Center. Although the room is relatively soundproof, the night before a launch is always different. Engine ignition test logs and launch scenarios keep running through his mind, making it hard to fall asleep. He said, "It's less about trying to sleep and more about lying down and going over the checklist again."

Nuriho Flight 4 heading to space at 1:13 AM on November 27, 2025. Photo by Korea Aerospace Research Institute

At 7:00 AM, he woke up at his usual time. As is his habit on important days, he shaved carefully, and as usual, skipped breakfast. All he needed, as always, was water.

The 600 meters from his accommodation to the launch vehicle assembly building is his "time for reflection." Every day, he walks this path, slowly reviewing the issues from the previous day and the checks that need to be done today. On launch day, the schedule proceeds from inspecting the assembly building, then heading to the launch pad, and finally moving to the Mission Control Center (MDC).

An Unexpected Variable: 'Umbilical Pressure Sensor'

Everything went according to plan up until around 11:00 PM, as the countdown continued. Propellant charging, launch pad inspection, and communications verification-all signals indicated "normal." The countdown quietly progressed toward the scheduled launch time of 12:55 AM.

Director Park Jongchan posing with Nuriho at the assembly building of Naro Space Center in Goheung, Jeonnam. Courtesy of Korea Aerospace Research Institute

However, about 40 minutes before launch, the atmosphere inside the MDC suddenly froze. The "umbilical retrieval pressure sensor" signal coming from the launch pad showed an abnormal pattern. Director Park immediately broke the silence and issued instructions to the team.

"Everyone hold position. Recheck the sensor."

Launch pad engineers manually checked the pneumatic line to directly verify the sensor's actual "pressure" status. Fortunately, the result was normal pressure; the problem was only with the sensor signal. However, the time to enter the automated launch operation (PLO) had already slipped. The Launch Management Committee made a swift decision.

"We will go for 1:13 AM, the last window of the allowed launch time."

Inside the MDC, every wristwatch was checked with tension. Director Park described the moment this way: "The launch pad always throws variables. Today, it was just a little later than planned."

Tension Among 700 Signals... The Decision Four Seconds Before Liftoff

Ten minutes before the countdown, the automated launch operation (PLO) was reactivated. Once started, this procedure could not be stopped. On the screens, 700 sensor signals lit up in green, and each team member's gaze was fixed on their console.

Four seconds before engine ignition, a sharp rise in the first-stage engine pressure appeared on the graph. This was the moment Director Park always refers to as "the moment Nuri is permitted to reach ground zero."

"Thrust is normal."

With a single word, he made the decision. The vehicle hold-down device (VHD) was released, and at 1:13 AM, the Nuri rocket began to soar through the dark sky over Goheung, Jeonnam.

All Satellites Separated... Director Park's Breathless 16 Minutes

The Nuri rocket separated its first stage two minutes after liftoff, and the fairing was jettisoned about three minutes and fifty seconds later. At four minutes and thirty seconds, the second stage separated. Each time these events were displayed in real time on the MDC screen, Director Park's fingers trembled slightly.

As the third-stage engine maintained stable thrust past an altitude of 300 km, only one task remained: confirming that all 13 satellites were not just "falling," but "departing from their designated positions."

At 1:31 AM, the separation signal for the main payload, the Next-Generation Medium Satellite No. 3, was heard over the MDC speakers. After that, every 20 seconds, a "beep" sounded repeatedly.

"Number 2, number 3 separated."

"Number 4, number 5..."

As the engineers called out the numbers, Director Park silently watched the screen. When all 13 dots turned "green and stable," he finally leaned back in his chair for the first time.

"Today... the equipment gave us the right answer."

In the early morning of the 27th, after the successful 4th launch of the Nuri rocket, Director Park Jongchan (the person wearing headphones) at the Naro Space Center Mission Control Center (MDC) is embracing a colleague, sharing joy. Photo by Korea Aerospace Research Institute

The End of the Launch Is Not the End

While the Nuri rocket was heading into space, the launch pad team moved immediately. They checked for structural damage caused by flames and began the procedure to recover any remaining propellant. Pressure reduction in the pipes and the cooling process continued as well.

Director Park continued his work, compiling the satellite separation signal records and delivering them to the Korea Aerospace Administration and each operating agency. It was after 4:00 AM when he finally returned to his accommodation. But he said,

"Although the Nuri rocket has departed, the launch pad will rise again tomorrow. We have to prepare for the next launch."

Thus, another night passed at Naro Space Center.