「Ｈ３」打ち上げ、延期の公算　エンジン課題解消せず―ＪＡＸＡ

　宇宙航空研究開発機構（ＪＡＸＡ）と三菱重工業が開発中の新型ロケット「Ｈ３」について、今年度内に予定していた初号機打ち上げが延期となる公算が大きいことが１７日、分かった。主エンジンで見つかった不具合が解消していないためで、事前の燃焼試験などを考慮すると、残り２カ月半で打ち上げにこぎ着けるのは困難とみられる。
　ＪＡＸＡは、現時点で延期の判断はしていないとした上で、「打ち上げ時期については、慎重に検討を進める」とした。（2022/01/17-22:10）

The Japan Aerospace Exploration Agency, or JAXA, is likely to postpone the launch of the new H-3 rocket, planned before the end of March this year, as problems with its main engine are yet to be fixed, according to informed sources.
   Considering the need to carry out a prior firing test, it is apparently difficult for JAXA to launch the first model of the H-3 rocket within two and a half months, the sources said.
   JAXA said it has not made any judgment on the postponement, adding that it will give careful consideration to the timing of the launch.
   The H-3 rocket, the successor to the existing H-2A rocket, has been under development jointly by JAXA and Mitsubishi Heavy Industries Ltd. since fiscal 2014. It will be equipped with two or three newly developed LE-9 first-stage main engines.
   In May 2020, after an engine firing test, cracks caused by metallic fatigue were found in turbine blades of a device that pumps liquefied hydrogen into the firing chamber. The agency judged that changing the turbine design would be inevitable and postponed the new rocket's launch, which was planned by the end of March 2021, by one year.