Operations and communications experiments of ETS-VI on an elliptical orbit

Engineering Test Satellite VI (ETS-VI) is the sixth Japanese engineering test satellite and was planned to conduct communications and bus experiments. ETS-VI was launched on August 28, 1994. It was injected into a geostationary transfer orbit and named "Kiku-6" after the injection. However, its liquid apogee engine for the injection into a geostationary orbit (GEO) did not fire with full thrust levels and ETS-VI was put into an elliptical orbit unexpectedly. This paper describes operations being able to establish its three-axis stabilization on this elliptical orbit. New functions for the establishment of its three-axis stabilization were added to an attitude control flight software (ACFS) of ETS-VI. Moreover, an attitude control function for realizing communications experiments was added in order to point antenna beams to ground stations. Results of the communications experiments and bus experiments which were achieved on this orbit are also described.