The next-generation launch vehicle development project, responsible for the launch of a lunar lander in 2032, is entering a major overhaul. The Korea Aerospace Research Institute is grappling with plans to enhance the engine performance of the next-generation launch vehicle and shifting to a reusable methane engine.
According to the Korea Aerospace Research Institute and relevant experts on the 10th, the Next-Generation Launch Vehicle Development Project Team is conducting a System Design Review (SDR). This is the stage for adjusting the specifications and direction of the launch vehicle. The Korea Aerospace Research Institute plans to finalize the development plan for the next-generation launch vehicle at the National Space Commission scheduled for the end of this month or next month.
The next-generation launch vehicle development project aims to develop a new space launch vehicle that provides more than three times the performance of the Korean launch vehicle Nuri. It was determined through the government's preliminary feasibility study that over 2 trillion won will be invested over 10 years, and Hanwha Aerospace was selected as the comprehensive enterprise last year.
However, the next-generation launch vehicle development project has faced many issues from the beginning. Hanwha Aerospace and the Korea Aerospace Research Institute have been in conflict over intellectual property rights since last year. A larger problem is performance. Concerns have been raised that the performance of the engine, which is the most critical component of the launch vehicle, is insufficient.
According to the design disclosed during the preliminary feasibility study, the next-generation launch vehicle is planned to cluster five liquid fuel engines with a thrust of 100 tons in the first stage and configure the second stage with two liquid engines of 10 tons each. If this plan is followed, the first-stage thrust would be 500 tons, but experts have indicated that this level would make it difficult to successfully send a lunar lander. One launch vehicle specialist noted, "With the current engine level, the payload that can be sent to the lunar transfer orbit is about 800 kg," adding that "It is far too insufficient for the government's goals of sending a payload to the lunar transfer orbit."
As a result, at the System Requirement Review (SRR) held in July last year, the Korea Aerospace Research Institute considered increasing the first stage engine from five to seven units. (Reference: [Exclusive] The next-generation launch vehicle heading for the moon will increase the first stage engine to seven.)
Additionally, recently, there has been consideration to change the launch vehicle engine to a reusable methane engine. An aerospace industry official stated, "It has been confirmed that the plan to change the next-generation launch vehicle development plan has been made, and the Korea Aerospace Research Institute is deliberating between two options: enhancing engine performance and switching to a methane engine."
So far, the Korean launch vehicle has used kerosene as fuel. Kerosene exists as a liquid at room temperature and has low volatility, making it easy to handle. However, in the combustion process, a significant amount of residue is produced, sticking inside the engine, making reusability of rocket engines using kerosene difficult. Nuri also used kerosene as fuel, and the next-generation launch vehicle was also planned to use kerosene.
However, as SpaceX has commercialized reusable launch vehicle technology using methane engines, there is growing support for the development of methane engines domestically. Unlike kerosene, methane does not produce residue inside the engine, making reuse feasible. Recently, Blue Origin's 'New Glenn', which successfully launched a test mission, and the Chinese private space company LandSpace also use methane engines. Methane engines can be reused, significantly reducing launch costs, which is why most private space corporations prioritize methane engines.
Within the Korea Aerospace Research Institute, option two, which shifts to the globally dominant methane engine before serious development begins, is gaining ground over option one, which enhances engine performance. A private space expert participating in the National Space Commission stated, "The methane engine is a technology that Administrator Yoon Young-bin has advocated for a long time, and there is considerable consensus in the Korea Aerospace Research Institute on changing the next-generation launch vehicle to methane. Most experts also believe that fundamental changes are needed rather than just adding more engines."
Changing the next-generation launch vehicle engine is not an easy task. To alter the next-generation launch vehicle development plan, a decision from the National Space Commission is necessary, and it is questionable whether the Korea Aerospace Research Institute can make such a significant decision in the absence of the Chairperson, who is the president. There is also the issue of the contract with Hanwha Aerospace, which is responsible for the comprehensive system of the next-generation launch vehicle. If the critical engine of the launch vehicle is changed, the contract itself must be redesigned, and the key question is whether Hanwha Aerospace will agree to this. An aerospace industry official noted, "The Korea Aerospace Research Institute maintains that Hanwha Aerospace agreed to the change in the plan, but Hanwha Aerospace has not released an official stance, which could lead to renewed conflict."
Changes are also inevitable for the lunar lander launch plan scheduled for 2032. The lunar lander is planned to be sent to the moon using the next-generation launch vehicle, but the likelihood that methane engine development will not be completed by 2032 is high. Another aerospace industry official pointed out, "Changing the next-generation launch vehicle to a methane engine is akin to declaring that we will launch the lunar lander with an American rocket instead of our own rocket," adding that, "The commitment to send our satellite and payload into space using our rocket and create an independent new space system has essentially vanished."
In response, the Korea Aerospace Research Institute stated that it is reviewing detailed plans to develop methane engines, securing early reusable launch vehicle technology, and simultaneously meeting the schedule for the lunar lander launch in 2032.
Recently, the increasing likelihood that the United States National Aeronautics and Space Administration (NASA) will abandon the development of the Space Launch System (SLS) has bolstered the Korea Aerospace Research Institute. Boeing, responsible for the SLS development, recently informed employees involved in the SLS program about the potential cessation of the program and that significant restructuring is expected. Former President Donald Trump had pledged during his candidacy to discontinue the SLS program. The SLS is not reusable and costs $2 billion (about 3 trillion won) per launch. The Trump administration has been planning to conduct lunar and Mars exploration using SpaceX's reusable launch vehicles instead of the SLS.