INSAT-3C Placed in Geo-stationary Orbit, Deployment of Appendages Completed

Since its injection into orbit on January 24, 2002, INSAT-3C has been successfully maneuvered to move it into geo-stationary orbit. The orbit rising maneuvers were carried out in phases by firing the 440 Newton Liquid Apogee Motor (LAM). The satellite carried about 1.5 tonne of propellant (Mono-Methyl Hydrazine – MMH and Mixed Oxides of Nitrogen – MON-3) for orbit raising operations as well as for station keeping and in-orbit attitude control. The first maneuver was carried out on January 25, 2002 by firing the LAM for 59 minutes that raised the orbit from 570 km X 35,920 km to 9,350 km X 35,936 km and reducing the orbital inclination with respect to the equator from 4 deg at the time of injection to 1.75 deg. The orbital period was 13.62 hours.

The second maneuver was carried out on January 26, 2002 by firing the LAM for 30 minutes to raise the orbit to 18,340 km X 35,787 km with a period of 16.9 hours and an inclination of 0.74 deg.

The third maneuver was carried out on January 28, 2002 by firing the LAM for 26 minutes raising the orbit to 32,448 km X 35,785 km with an orbital period of 22.5 hours and reducing the inclination to 0.18 deg. Since this maneuver, the satellite has been in continuous radio visibility of MCF, Hassan.

The last maneuver was on January 30, 2002 with a 3 minute firing of LAM that brought the satellite to near geo-stationary orbit. The satellite at the end of this maneuver was at 63 deg East longitude and drifting at 2 deg per day towards its designated orbital slot at 74 deg East longitude.

Deployment of Appendages

The deployment of the appendages of INSAT-3C was completed on January 31, 2002. First the solar array on the south side of the satellite was deployed at 9:46 am which was followed by the deployment of the antenna on the west side at 10:35 am.. The solar array on the north side of the satellite was deployed at 11:47 am and finally the antenna on the east side was deployed at 12:21 pm. INSAT-3C has since been put in its final three axis stabilised mode on February 1, 2002.

All the systems of INSAT-3C have been performing as per predictions. The satellite has 488 kg fuel left on board which will be sufficient for its design life of 12 years.

Further Activities

The testing of the individual transponders will commence soon. INSAT-3C is expected to be commissioned by end of February 2002.