On December 22, 2025, Japan used H3 rocket No. 8 to launch the "Yinlu-5" navigation satellite. About 20 minutes after the rocket took off, the secondary engine stopped working early, causing the satellite to fail to enter the intended orbit, and the launch mission failed.
This is also another setback for the H3 rocket, Japan’s new generation of main launch vehicle. As early as March 2023, its first launch also ended in failure, and reliability issues continue to attract attention.
According to CCTV news reports, the Japanese Ministry of Education, Culture, Sports, Science and Technology held a meeting recently, confirmed that the reason for the failure of the H3 rocket No. 8 launch was the poor fit of the base material of the rocket carrying the satellite.
It is understood that this conclusion comes from a report compiled by an expert meeting of the Japanese Ministry of Education, Culture, Sports, Science and Technology on the 22nd.
The report pointed out that the panels that make up the base had poor internal fit during the manufacturing stage. The resulting gap expanded during the rocket's flight, ultimately leading to mission failure.
This accident once again exposed that Japan still needs to improve its manufacturing and quality control of new-generation launch vehicles. Subsequent improvements will directly affect the commercial launch competitiveness of the H3 rocket.
