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Press Release



  Mar 23,2000

First Orbit Raising Manoeuvre on INSAT-3B Completed

The 440 Newton thrust Liquid Apogee Motor (LAM) on board INSAT-3B was successfully fired this morning March 23, 2000 at 7:29 am IST placing the satellite in its first Intermediate Orbit (IO-1). The LAM was fired for a duration of 64 minutes 24 seconds. About 534 kg of propellant on board the satellite -- Mono Methyl Hydrazine (MMH) and Mixed Oxides of Nitrogen (MON-3) -- was consumed in today's LAM firing exactly as planned. This major orbit manoeuvre opera-tion conducted from the INSAT Master Control Facility at Hassan (MCF), has raised the perigee of the satel-lite from 560 km at the time of its injection to about 14,214 km. The apogee altitude remains same as at the time of injection. The inclination of the orbit has been reduced from 7 degree at the time of injection to 1.8 degree by today's firing of LAM. The orbital period is now about 15:32 hours.

INSAT-3B, was launched yesterday (March 22, 2000) by Ariane-505 launch vehicle from Kourou in French Guyana. Soon after the launch, the satellite health was monitored in terms of power generation, thermal conditions, orientation control and other parameters all of which were normal. Before the satellite went out of radio visibility of MCF at 3.36 pm (IST) yesterday, the satellite had been manoeuvred for Apogee Motor Firing (AMF) orientation.

MCF reacquired the signal from the satellite this morning at 02:36 am IST as expected and the earth acquisition and gyro calibration were completed before the AMF-1 was commenced. The satellite will go out of radio visibility of MCF at 14:08 pm IST this afternoon and again come within its visibility at about 08.10 am IST tomorrow.

Precise orbit determination is being carried out by ranging from the network of ground stations. The second orbit raising operation is scheduled at about 02:30 pm IST tomorrow (March 24, 2000). All the systems on board INSAT-3B are functioning normally.