日本新构型H3运载火箭研发遭遇困难

Core Points - The Japan Aerospace Exploration Agency (JAXA) reported that the H3 rocket's sixth unit experienced a failure during an engine combustion test in July, potentially delaying its planned launch within the current fiscal year [1] - The H3 rocket is Japan's next-generation main launch vehicle, developed in collaboration with Mitsubishi Heavy Industries [1] - The sixth unit of the H3 rocket features a new "3-0" configuration, utilizing three liquid fuel engines without boosters, marking Japan's first launch of a large liquid-fueled rocket without boosters [1] Group 1 - The failure during the July test was due to insufficient pressure in the hydrogen and oxygen fuel tanks, which hindered the supply of adequate fuel to the main engine [1] - JAXA indicated that resolving this issue and conducting a new test will take time, which may prevent the sixth unit's launch as scheduled in the fiscal year 2025 (April 2025 to March 2026) [1] Group 2 - JAXA stated that the issues with the "3-0" configuration do not affect the H3 rocket's seventh unit, which is still scheduled for launch in late October this year [2] - Additionally, JAXA reported on the development of the small solid-fuel rocket "Epsilon S," which encountered combustion anomalies and a fire during a second-stage engine test in November 2024 [2] - To expedite the Epsilon S's operational readiness, JAXA is considering changing the second-stage engine from the currently developed E-21 to the M-35 engine used in its predecessor, the enhanced Epsilon, although this change may reduce its launch capacity below initial targets [2]