[Q&A] Goh Jung-hwan, Head of KAIST Space Center: "Nuriho Launch Impossible Tomorrow... Need to Inspect to Know"

[Asia Economy Reporter Kim Bong-su] The second launch of the Korean space launch vehicle Nuri, scheduled for the 16th, has been temporarily suspended due to a sensor malfunction. On the afternoon of the 15th, Nuri, which had been mounted on the second launch pad at Naro Space Center in Goheung-gun, Jeollanam-do, was currently taken down and transported to the assembly building for a detailed inspection. The inspection, repair, and verification will take at least seven days, so it is uncertain whether the launch can be resumed before the backup launch date on the 24th. The following is a Q&A with Ko Jeong-hwan, Head of the Korean Launch Vehicle Development Project at the Korea Aerospace Research Institute (KARI).

- How will the launch schedule change?

△ It depends on which part is malfunctioning. At this point, we do not know which part is the problem. We need to analyze it to know clearly. It is necessary to transport it as soon as possible for inspection.

- Can it be done within the backup launch date?

△ We have spare sensors and electrical harnesses. It is necessary to quickly identify the cause. The schedule will be set accordingly. We plan to continue inspections and confirmations.

- When, how, and why did the problem occur?

△ We completed inspections of electrical equipment and sensors during the assembly process. After that, we proceeded with the final assembly and launch preparations, and there were no issues during that process either.

- What problems arise if the oxidizer filling level measurement sensor malfunctions?

△ Other electrical inspections showed no abnormalities, but one sensor showed unusual values. Work stopped in that state. Attempts were made on-site to identify the cause, but it was difficult.

- What is believed to be the cause?

△ The sensor itself might be faulty, or the cable could be defective, or the terminal (signal converter) might be malfunctioning. If it does not operate properly, it is difficult to measure how much oxidizer is loaded. The oxidizer tank issue in the first launch was a mechanical problem, but this sensor malfunction appears to be an electrical problem. The oxidizer is in an ultra-low temperature state at minus 183 degrees Celsius, so it is not a simple sensor. This was an unforeseen issue during the first launch.

- How extensive is the repair needed?

△ To physically replace the sensor, the oxidizer tank lid must be opened. However, if the problem is with the electrical connection wires or the terminal box, only the affected part needs to be replaced. How quickly repairs can be made depends on which part is problematic and how.

- Is a launch tomorrow impossible?

△ The vehicle that was upright is being laid down again and transported to the assembly building. A launch tomorrow is difficult. Currently, the top priority is to inspect as quickly as possible. Until the inspection is complete and the problematic part is identified, it is difficult to provide a schedule. If it cannot be done by the backup dates (17th to 23rd), we will have to follow procedures to notify the international community and set a new launch schedule. Internally, the repairs will be reviewed, finalized, and verified, then a launch management committee will be held to set the next launch date.

- How do you feel right now?

△ I am embarrassed and sorry that this happened. We will do everything possible to resolve the issue and make a sure fix to challenge again.

- Was the wet dress rehearsal conducted?

△ It was conducted during the first launch since it was the first time. It is done to check for problems during oxidizer filling and discharge. This time, after internal review, it was decided not to conduct it because it would take a lot of time and could strain the vehicle. The issue today occurred before oxidizer filling. The problem may not be fundamental but a simple hardware issue.

- Could internal payloads like CubeSats be affected by long-term storage?

△ If done quickly, there is no problem. If delayed, they may be taken down and moved to the preparation building for storage.

- Does this happen often?

△ Even overseas, there are frequent cases where launches are stopped or delayed due to sensor errors related to liquid oxygen during launch vehicle preparation.

This content was produced with the assistance of AI translation services.