Study on the orbital maneuvering capability of H-2A kick stage

Abstract

This paper describes a concept study of an optional kick stage system named “PLUS (for Planetary mission, Long-duration small-thrust Upper Stage)” equipped with a relatively small-thrust engine for interplanetary missions. The thrust force of PLUS assumed in this study is a maximum 29.4kN, which is relatively small, used to inject a payload into interplanetary orbit with sufficiently low gravity loss i.e. less than 2%, although two split delta-Vs such as the Russian Proton/Breeze-M will improve performance efficiency (Proton Launch System Mission Planner's Guide, 2009 [1]). The orbital maneuvering capability of PLUS system is evaluated through Mars orbital maneuvering simulations. In this study, two types of PLUS systems are assumed. First, a 29.4kN thrust force kicks stage system designated as “PLUS1” to inject the 3000kg main payload into Mars transfer orbit. Second, a 9.8kN thrust force small PLUS system designated as “PLUS2” to inject a 500kg secondary payload into Mars transfer orbit. In the first case, the above-mentioned split delta-Vs are conducted to inject the main payload into Mars transfer orbit with sufficiently low gravity loss. In the second case, on the other hand, PLUS2 attached to the secondary payload is dual launched together with a primary payload into a geostationary transfer orbit, GTO, whereupon PLUS2 is initiated slightly before perigee to inject the secondary payload into Mars transfer orbit utilizing Electric delta-V Earth Gravity Assist, EDVEGA scheme via the on-board Ion Electric propulsion System, IES (Kawaguchi, 2001 [2,3]). Throughout the simulations, some optimized configurations of PLUS system covering a wide variety of space missions are suggested in this paper.