Satoshi Nonaka, Takashi Ito, Yoshifumi Inatani
PROMOTE THE PROGRESS OF THE PACIFIC-BASIN REGION THROUGH SPACE INNOVATION 166 255-264 2019年
In order to make the access to space for scientific researches much easier and make the opportunities of the rocket launches much frequent, a fully reusable sounding rocket is proposed in ISAS/JAXA. The mission definition of the proposed reusable sounding rocket are 1) To achieve 100km in altitude and returns to the launch site, 2) The 100kg payload to be carried, 3) Flight frequency is higher than 10 times per a year, 4) The minimum flight interval is one day, and 5) Operational flight cost should be an order of magnitude less than the existing ISAS sounding rocket. Reusable sounding rocket is different from the present expendable rockets in 1) repeated operations, 2) returning flight / reignition of engine / vertical landing, that is, 3) fault tolerant / health management. Some key technologies related to these characteristics of reusable system have been verified to design an operative reusable sounding rocket in phase-A. Technologies verifications respect to the reusable vehicle, 1) reusable engine development and repeated operations, 2) reusable insulation development for cryogenic tank, 3) aerodynamic design and model flight demonstration for returning flight, 4) cryogenic liquid propellant management demonstration, 5) landing gear development, and 6) health management system construction, have been successfully conducted from 2010 to 2016.After these technical demonstrations, we are proceeding with a study for system level verifications by a flight demonstrator from 2016 as the next step for the development of reusable sounding rocket. In this plan, a small test vehicle will be established for repeated flight demonstrations. Objectives of the demonstration are 1) system architecture study for repeated flight operation such as quick turnaround operation and fault tolerant design method, 2) life controlled and frequently repeated use of cryogenic propulsion system and its flight demonstrations, 3) study for the advanced returning flight method of vertical landers and its flight demonstrations, and 4) demonstration of advanced technology for future RLVs such as more composite on board, in flight fuel management, GH2/GOX auxiliary propulsion, health management, long-life & high performance engine. These system level studies by a reusable flight demonstrator will be conducted for next three years.