South Korea has entered the stage of verifying core technologies for a reusable launch vehicle on an actual flight vehicle. After shifting the direction of its next-generation launch vehicle program (KSLV-III) to a reusable design last year, the country will conduct low-altitude vertical takeoff and landing flight tests domestically in 2028.
The Korea Aerospace Research Institute (KARI) said on Sept. 29 that it had begun assembling the first flight model of a reusable technology demonstrator at Hanwha Aerospace's assembly plant in Suncheon. The demonstrator stands 12.2 meters tall with a diameter of 1.5 meters and weighs 6.4 tons, and will be fitted with one 8-ton-class liquid rocket engine and four landing legs.
The demonstrator is a test vehicle designed to verify core technologies — ascent and descent, attitude control, guidance to a target point and vertical landing — ahead of developing an actual reusable launch vehicle. Reusing a launch vehicle requires not only the technology to restart engines repeatedly but also the ability to precisely control position and attitude during flight and to withstand the impact of landing.
KARI plans to carry out combustion tests of the engine development model and manufacture components through this year, and to complete combustion tests of two engine flight models along with assembly and functional testing of the demonstrator by 2027. In 2028, it will conduct ground combustion tests at the Naro Space Center followed by two flight tests to verify vertical takeoff and landing performance.
The project is largely a preliminary test stemming from the decision to convert the next-generation launch vehicle to a reusable design. At the end of 2025, the government changed its development plan so that the first stage of the next-generation launch vehicle, originally designed for single use, would be recovered and reused. The goal is to apply an 80-ton-class methane engine to improve reusability and launch economics.
Overseas, tests using small demonstrators are also actively under way ahead of full-scale reusable launch vehicle development. SpaceX repeatedly conducted vertical takeoff and landing tests to altitudes of about 700 meters using its Grasshopper vehicle, building the foundation for the technology to recover the Falcon 9 first stage. KARI likewise plans to use the demonstrator to reduce in advance the technical risks that could arise during actual launch vehicle development. Lee Sang-chul, president of KARI, said the institute would verify the technologies needed for reusable launch vehicle development in advance through the demonstrator and accumulate development experience.
