Hirohide Ikeda

Endurance Firing Test Results of the Long Life 1N Hydrazine Thruster

Monopropellant Hydrazine Thrusters are widely used in many satellites and explorers propulsion systems and launch vehicle RCSs due to their simple and low cost features. The first generation Japanese 1N thruster design is based on the US TRW 1970s design, with a service life insufficient for modern satellite programs, hence the new 1N thruster, with a long catalyst bed life, is awaited. From 2002, JAXA commenced a study to extend the life of the 1N thruster with BBM (Bread Board Model) and EM (Engineering Model) thruster firing tests. In 2010, four types of PM (Prototype Model) thrusters were constructed and Qualification Tests, including Endurance Firing Tests, were conducted. In 2011, the cumulative impulse of 210kNsec (Hydrazine Throughput exceeded 100kg) and cumulative pulse of 870k were achieved with all PM thrusters. Reports of the new 1N thruster Qualification test as well as the overall development program history are described in this paper.

Development of New Composite Propellant Tank for Satellites

Satellite components falling to the ground are a crucial problem, particularly titanium tanks in propulsion systems. Satellite tanks are generally made of titanium alloy because it is light and compatible with propellants used for the satellite. However, it also has a high melting point, which hinders melting on re-entry. To replace the titanium tanks, JAXA has studied as the tank for ground damage prevention on re-entry since 2010 and has started developing a new composite propellant tank since 2013. The tank is targeted; not only due to its demise properties but also its extended propellant storage, cost-effectiveness and a short delivery time. For the first development step, the minimum tank (DM: Development Model #1) which has the shortest cylindrical segment length and a volume of 250L were manufactured to confirm the strength proof of critical portions and the adequacy of production techniques. There are also plans to manufacture a PMD (Propellant Management Device) separately to the tank shell. This paper describes the design, trial productions, and data acquisition tests used when developing the new tank.

Research and Development Activities on JAXA’s Spacecraft Propulsion

This chapter will provide recent activities and plans for spacecraft in JAXA (Japan Aerospace Exploration Agency). In these years, JAXA launched many spacecraft, such as earth observation satellites, geostationary satellites, and HTV (H-II Transfer Vehicle). The details of propulsion system of these spacecrafts are introduced.