Nuriho 1st Launch Investigation Committee Formed... "Seeking Cause of Early Shutdown of 3rd Stage Engine"

[Image source=Yonhap News]

[Asia Economy Reporter Kim Bong-su] The government has begun a full-scale analysis of the cause of the early shutdown of the third-stage engine, which led to the '2% short' success of the first Nuriho launch.

On the 3rd, the Ministry of Science and ICT, together with the Korea Aerospace Research Institute (KARI), launched and held the first meeting of the 'Launch Investigation Committee' for the first Korean launch vehicle 'Nuriho,' which was launched on the 21st of last month.

Nuriho was developed over 11 years and 7 months since 2010, with a total investment of 1.9572 trillion won, culminating in the first launch. The first stage 75-ton engine clustering and the second stage 75-ton engine operated normally, and procedures such as separation of each stage and payload fairing, as well as satellite mock-up separation, were all carried out successfully. However, the third stage 7-ton engine shut down about 46 seconds earlier than planned, causing the final acceleration to fall short of the target speed of 7.5 km/s, resulting in failure to insert the satellite mock-up into orbit, which was the mission.

Accordingly, the committee formed on this day is expected to focus on analyzing the cause of the early shutdown of the third-stage engine and reach a conclusion within this month. The committee includes KARI researchers, who are the main developers of Nuriho, dedicated evaluation members who have advised on Nuriho development, and private experts to incorporate new external perspectives.

Currently, KARI researchers are organizing and conducting detailed investigations and analyses of over 2,400 flight data points measured at tracking stations (Naro Space Center, Jeju, Palau).

The committee also discussed the main remote reception information (Quick Look Message) that captured Nuriho's real-time flight status. According to this, Nuriho's propellant tank pressure and engine operation appeared normal during the first and second stage flights. However, in the third stage flight section, the oxidizer tank pressure dropped, reducing engine thrust and acceleration, which led to engine combustion stopping. Possible causes under review include issues with the airtightness of the oxidizer tank and piping/valves, or abnormalities in sensors controlling the oxidizer tank pressure.

Choi Hwan-seok, Deputy Director of KARI and chair of the committee, stated, “We will hold an internal review meeting at KARI early this month to discuss detailed flight data results analyzed by each person in charge and specify various possibilities that could have lowered the third-stage oxidizer tank pressure. We plan to hold a second committee meeting to review the main issues discussed. Based on the opinions from that meeting, we will conduct additional analyses, carry out preliminary organization of various possibilities, and the committee will verify these accordingly,” he explained.

Meanwhile, KARI plans to conduct a second launch in May next year. Additionally, four more launches will be conducted by 2027 to verify performance and reliability.

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