Commissioned in 1983, Insat was the largest domestic communication system in the Asia-Pacific Region, and was a joint venture of the Indian Department of Space (DOS), Department of Telecommunications, India Meteorological Department, All India Radio and Doordarshan. As of 2004 the Insat space segment consisted of: Insat-1D, last of the Insat-1 series launched in 1990; three ISRO-built satellites, Insat-2A launched in July 1992, Insat-2B launched in July 1993 and Insat-2C launched on December 7, 1995; Insat-2DT acquired from Arabsat; Insat-2E launched on April 3,1999; Insat-3B launched on March 22nd 2000; Insat-3C launched on January 24th 2002; Insat-3A launched on April 10th 2003; Insat-3E launched on September 28th 2003; and Gsat-2 and Gsat-3. As of mid-2004 ISRO leased eleven 36 MHz equivalent units of C-band capacity on board Insat-2E to Intelsat.
Experimental communications satellite. Geosynchronous altitude, longitude 10 deg East. Positioned in geosynchronous orbit at 102 deg E in 1981-1982 As of 31 August 2001 located at 42.73 deg W drifting at 0.834 deg W per day. As of 2007 Mar 10 located at 39.31E drifting at 0.875W degrees per day.
Also carried transponders for domestic communications. Operational multipurpose satellite for telecommunications, meteorological, imaging and data relay, radio and television programme distribution and direct television broadcasting for community reception. Geosynchronous orbit longitude 74 E. A/AC.105/INF.391 was reissued as ST/SG/SER.E/79. Also registered by the United States as 1982-31A in ST/SG/SER.E/67, with category C and orbital parameters 1416.7 min, 35032 x 35783 km x 0.5 deg. Positioned in geosynchronous orbit at 73 deg E in 1982 As of 29 August 2001 located at 82.99 deg E drifting at 0.337 deg W per day. As of 2007 Mar 10 located at 39.55E drifting at 0.205W degrees per day.
Released from STS 8 8/31/83; also carried transponders for domestic communications. Operational multipurpose satellite for telecommunications, meteorological imaging and data relay, radio and television programme distribution and direct television broadcasting for community reception. Geostationary longitude 74.0 +/ - 0.1 deg E. Deployment from US Space Transportation System flight no 8, orbiter Challenger, on 31 Aug 1983. Positioned in geosynchronous orbit at 74 deg E in 1983-1992; 93 deg E in 1992-1993 As of 26 August 2001 located at 125.27 deg E drifting at 0.152 deg E per day. As of 2007 Mar 10 located at 80.35E drifting at 0.392E degrees per day.
Stationed at 93.5 deg E; also performed communications tasks. Operational multipurpose satellite for telecommunications, meteorological imaging and data relay, radio and television programme distribution and direct television broadcasting for community reception. Geosynchronous orbit longitude 93.5 +/- 0.1 deg east. Launch vehicle Ariane 3 launch vehicle of Arianespace, 24th flight of Ariane and 9th flight of the Ariane 3 version. Positioned in geosynchronous orbit at 93 deg E in 1988-1989 As of 4 September 2001 located at 58.51 deg E drifting at 0.073 deg E per day. As of 2007 Mar 11 located at 80.89E drifting at 0.154W degrees per day.
Also performed Indian domestic communications tasks; 83.1 E. Operational multi-purpose satellite for telecommunications, meteorological imaging and data relay, radio and television programme distribution and direct television broadcasting for community reception. Orbital position 83 deg E. Also registered as 1990-5 1A in ST/SG/SER.E/250 by the United States, with category B and orbital parameters 1426.3 min, 35768 x 35811 km x 0.2 deg. Positioned in geosynchronous orbit at 83 deg E in 1990-1999; 74 deg E in 1999-2000 As of 5 September 2001 located at 73.85 deg E drifting at 0.000 deg E per day. As of 2007 Mar 10 located at 71.63E drifting at 0.039E degrees per day.
Stationed at 74 deg E; also performed communications functions. INSAT-2A is a multi-purpose satellite, and it will provide the following services: Domestic long-distance telecommunications, meteorological earth observation and data collection services, direct satellite TV broadcasting to community TV receivers in rura l and remote areas, radio and TV progamme distribution, and Satellite Aided Search and Rescue services. Geostationary longitude 74 +/0 0.1 deg E. Positioned in geosynchronous orbit at 74 deg E in 1992-1999 As of 3 September 2001 located at 48.18 deg E drifting at 0.010 deg E per day. As of 2007 Mar 5 located at 25.76W drifting at 0.201W degrees per day.
Stationed at 93.5 deg E; also acted as communications platform; carried search and rescue package. INSAT-2B is a multi-purpose satellite, and it will provide the following services: Domestic long range communications, meteorological Earth observation and data collection service, Direct satellite TV broadcasting to community TV recievers in rural and re mote areas, Radio and TV programme distribution, satellite aided search and rescue services. Inclination will be reduced to 0.1 deg and maintained. Geostationary longitude 93.5 +/- 0.1 deg E. Launch on Arianespace flight 58. Positioned in geosynchronous orbit at 93 deg E in 1993-1999 As of 5 September 2001 located at 93.47 deg E drifting at 0.015 deg W per day. As of 2007 Mar 9 located at 63.82W drifting at 1.099W degrees per day.
ISRO's Insat 2E was placed in geostationary transfer orbit. The Indian-built satellite carried a C and S band communications package. Stationed at 83 deg E. Positioned in geosynchronous orbit at 83 deg E in 1999. As of 3 September 2001 located at 82.90 deg E drifting at 0.015 deg W per day. As of 2007 Mar 10 located at 82.93E drifting at 0.008W degrees per day.
Replaced the lost Insat 2D and carried a pure telecommunications payload of C, Ku and S band transponders. Stationed at 83 deg E. Positioned in geosynchronous orbit at 73 deg E in 2000. As of 5 September 2001 located at 83.07 deg E drifting at 0.014 deg W per day. As of 2007 Mar 11 located at 82.94E drifting at 0.012W degrees per day.
Experimental Rural Communications satellite. Launch delayed following pad abort on March 28. First launch of the Indian GSLV launch vehicle. GSat 1 was an Indian, 1500 kg scaled-dow) test model of a future geosynchronous communications spacecraft with a 440 N ISRO liquid apogee motor, and S-band and C-band ommunications transponders, similar to the Insat-2 satellites. The motor for the cryogenic, hydrogen-oxygen upper stage had been purchased from Russia but the design had never flown in space before. The stage cut off without providing the required delta-V - preliminary analysis revealed a shortfall of 0.5% in the thrust. An attempt was made to reach a usable orbit using the station-keeping motor of the GSAT satellite itself. After a series of burns, GSat 1 ran out of propellant - 10 kg more fuel would have been required to reach a stationary orbit. In the end, the parameters of the drifting (about 13 deg/day) orbit were period 23 hours, apogee 35,665 km, perigee 33,806 km, and inclination 0.99 deg. The fully functional transponders and transmitters on board were deactivated on instructions of the International Telecommunications Union. As of 4 September 2001 located at 54.88 deg E drifting at 13.212 deg E per day. As of 2007 Mar 10 located at 50.16W drifting at 12.778E degrees per day.
Communications satellite. Launch delayed from January 16. The Ariane placed Insat 3C into a geosynchronous transfer orbit. The Indian communications satellite had a mass of 1050 kg empty, 2750 kg fuelled. It carried 30 C-band and two S-band transponders. As of 2007 Mar 9 located at 73.96E drifting at 0.007W degrees per day.
Experimental Rural Communications. Launch delayed from original target of late 2001, then October 2002, then February 2003. The satellite carried four C-band transponders, two Ku-band transponders and a Mobile Satellite Service (MSS) payload operating in S-band and C-band for forward link and return link respectively. GSAT-2 also carried four piggyback experimental payloads: Total Radiation Dose Monitor (TRDM), Surface Charge Monitor (SCM), Solar X-ray Spectrometer (SOXS) and Coherent Radio Beacon Experiment (CRABEX). As of 2007 Mar 10 located at 47.97E drifting at 0.005E degrees per day.
The 440 Newton Liquid Apogee Motor (LAM) took the satellite from its Geosynchronous Transfer Orbit (GTO) of 649 km perigee and 36,000 km apogee with an orbital inclination of 7 deg. The LAM was fired for a total duration of 121 minutes in three phases on September 29, September 30 and October 1. A total velocity of 1460 m/sec was added by LAM at apogee. INSAT-3E had 1592 kg propellant at the time of its injection into GTO by Ariane-5 launch vehicle on September 28. After orbit raising operations, it had 510 kg of propellant remaining that was sufficient to arrest the drift and park it at its orbital slot as well as maintain the satellite in its orbit and controlling its orientation during its design life of more than 12 years. After the completion of the third apogee motor firing, the Solar Arrays and Antennae of INSAT-3E were deployed. The Sun tracking solar array of INSAT-3E had a total area of 29.6 sq m and it is designed to generate 2.9 kW (BoL) of power in orbit. The satellite had two deployable antennas and one fixed antenna. The satellite was expected to reach its final orbital slot of 55 deg E and be put into operation by November 2003. As of 2007 Mar 9 located at 54.97E drifting at 0.001W degrees per day. In 2014 the satellite was decommissioned; it began to slowly drift off station in late March and its orbit was lowered on April 4 to 35579 x 35693 km, drifting two degrees east per day.
Gsat-3 / Edusat was the first Indian satellite built exclusively for the educational sector. It was mainly intended to meet the demand for an interactive satellite based distance education system for India. Edusat was launched into a geosynchronous transfer orbit by its launch vehicle. Edusat was to reach geostationary orbit by firing, in stages, its on board Liquid Apogee Motor (LAM). In geostationary orbit the satellite was to be co-located with Kalpana-1 and Insat-3C satellites at 74 deg East longitude.
Compared to earlier satellites in the Insat series, Edusat used several new technologies. The spacecraft was built around the I-2K standardised spacecraft bus. It had a multiple spot beam antenna with a 1.2 m reflector to direct Ku band spot beams, a dual core bent heat pipe for thermal control, high efficiency multi-junction solar cells and an improved thruster configuration for optimised propellant use for orbit and orientation maintenance. The satellite used radiatively cooled Ku-band Travelling Wave Tube Amplifiers and a dielectrically loaded C-band demultiplexer for its communication payloads. Edusat carried five Ku-band transponders providing spot beams, one Ku-band transponder providing a national beam and six Extended C-band transponders with a national coverage beam. It was to join the Insat system that already provided more than 130 transponders in C-band, Extended C-band and Ku-band for a variety of telecommunication and television services.
First operational flight of launch vehicle. Launch delayed from July, August and September 10. Dry mass 820 kg. As of 2007 Mar 9 located at 73.92E drifting at 0.006W degrees per day.
Delayed from late July 2005. Launch delayed from August 23, October, November 14 and 30, December 8, 16 and 20. Dry mass 1385 kg. The satellite was equipped with Ku-band and C-band transponders and would join other Insats in providing telecommunications and television services to the Indian subcontinent. After three engine burns the satellite reached geostationary altitude over the Indian Ocean at 04:30 GMT on 26 December, then deployed its solar arrays. As of 2007 Mar 11 located at 83.00E drifting at 0.006W degrees per day.