• Rocket explosion

Test failure raises concerns over delays in space development

Another major setback has occurred in Japan’s rocket development. It is imperative to immediately ascertain the cause and take countermeasures so as not to lose the trust that has been built up to this point.

The second-stage engine of the new Epsilon S rocket exploded during a test at the Japan Aerospace Exploration Agency (JAXA) testing center in Noshiro, Akita Prefecture. Part of the building at the site was blown away, and the fire continued for about two hours. It was fortunate that no one was injured.

Epsilon S is an enhanced model of the current Epsilon, with an enlarged second-stage engine to boost the launch capacity. Tests of the first- and third-stage engines have already been successfully completed.

JAXA plans to launch the first Epsilon S rocket in fiscal 2024. It is a major blow that an explosion occurred during the testing of the second-stage engine, which is the final stage of development.

JAXA will need to redo the combustion test of the engine, but it will probably take some time to repair the test site. It is feared that the launch of the first vehicle will be delayed.

Japan’s core rockets are entering a period of generational change, but the shift has not been proceeding as smoothly as it should.

The rockets being developed by Japan are the small, solid-fuel Epsilon and the large, liquid-fuel H-2A.

Use of the H-2A will cease and it will be replaced by the new mainstay H3 rocket. However, in March this year, the H3’s first launch vehicle had to be destroyed during the flight, on command from the ground, after its second-stage engine failed to ignite.

The launch of the current Epsilon-6 also ended in failure last October due to inadequate manufacturing of the attitude control system.

In recent years, there has been growing commercial demand globally for the launch of multiple small satellites for use in communications and ground-based observation. JAXA had planned to cultivate a new market by reducing the cost of the current Epsilon.

Since rockets are comprised of numerous precision components, space development is said to always be accompanied by failures.

Nevertheless, with a continuing string of failures, one cannot help but have doubts about the technical competence of JAXA and the manufacturers. Are there any problems with the development system? Are the technologies being handed down to successors? All parties concerned should seriously address these issues and work to improve the situation.

In rocket development around the world, U.S. company SpaceX has taken a major lead in technology and dominates the market. It will not be easy for Japan to enter the competition, but it is hoped that this country will recover from its failures and move forward with space development.

(From The Yomiuri Shimbun, July 17, 2023)