1998 年 46 巻 539 号 p. 705-711
National Space Development Agency of Japan (NASDA) started to develop H-II launch vehicle in 1983 and succeeded in the 1st flight on February in 1994. Meanwhile, several troubles were experienced in the development of LE-7 which is the 1st stage engine of H-II. The LE-7 is a staged combustion cycle engine with high pressure and high Isp like SSME. Therefore, high delivery pressure and high performance were required for LH2 turbopump, which is the main key component, and caused several troubles in the development. This paper describes the development of LH2 turbopump containing the design description, the contents of some troubles and their counterplans. In addition, some activities to solve turbopump life and endurance will be introduced.