From: Indian Space Research Organisation
Posted: Sunday, September 2, 2007
India's Geosynchronous Satellite Launch Vehicle, GSLV-F04, had a successful launch today (September 2, 2007) at 18.20 hours from Satish Dhawan Space Centre SHAR (SDSC SHAR), Sriharikota and it placed India’s INSAT-4CR into the Geosynchronous Transfer Orbit (GTO). This was the fifth flight of GSLV and the fourth successful one.
INSAT-4CR is now orbiting the Earth in GTO with a perigee (nearest point to Earth) of 168 km and an apogee (farthest point to Earth) of 34,710 km with an orbital inclination of 20.7 deg with respect to the equator.
At 4.8 seconds before count down reached zero, the four liquid propellant strap-on stages, each carrying 40 tonne of liquid propellants, were ignited. At count zero and after confirming normal performance of all the four strap-on motors, the 138 tonne solid propellant core stage was ignited and the 414 tonne, 49 m tall GSLV blazed into the sky. The important flight phases included the first stage and strap-on stage propulsion, payload fairing separation at an altitude of 115 km, the second stage propulsion and the cryogenic stage propulsion. The cryogenic propulsion stage was shut down after attaining the required velocity of 10.2 km per second. The 2,140 kg INSAT-4CR was placed in orbit about seventeen minutes after lift off, about 5,000 km away from Sriharikota.
GSLV was commissioned after both its developmental test flights conducted in April 2001 and May 2003 were successful. In its first operational flight on September 20, 2004, GSLV launched the 1,950 kg EDUSAT into GTO. However, the second operational flight, GSLV-F02, with INSAT-4C on board, conducted on July 10, 2006, did not succeed. The Failure Analysis Committee (FAC), constituted to review the reasons for the failure, concluded that the primary cause for the failure was the sudden loss of thrust in one of the four liquid propellant strap-on motors (S4) immediately after lift-off resulting from the malfunctioning of a propellant regulator. FAC also concluded that the design of GSLV is robust and recommended implementation of stricter control on fabrication, inspection and acceptance procedures. The recommendations of FAC had been implemented in GSLV-F04.
GSLV was designed and developed by Vikram Sarabhai Space Centre, Thiruvananthapuram. The inertial systems for the vehicle were developed by the ISRO Inertial Systems Unit (IISU) at Thiruvananthapuram. The Liquid Propulsion Systems Centre (LPSC) also at Thiruvananthapuram developed the Liquid propulsion stages for the strap-ons and the second stage of GSLV as well as the reaction control systems. While the Russian supplied cryogenic stage is used for third stage propulsion, the guidance and control of the stage has been implemented by ISRO. Satish Dhawan Space Centre SHAR is the launch centre for all the launch vehicles of ISRO. ISRO Telemetry, Tracking and Command network (ISTRAC) provides Telemetry, Tracking and Command support.
INSAT-4CR Solar Array Deployed
INSAT-4CR is the third satellite in INSAT-4 series. It carries 12 high-power Ku-band transponders designed to provide Direct-To-home (DTH) television services, Video Picture Transmission (VPT) and Digital Satellite News Gathering (DSNG). It was built to replace an identical satellite, INSAT-4C that was lost due to the failure of GSLV-F02 in July 2006.
Soon after its injection into to GTO, the two solar arrays of INSAT-4CR were automatically deployed. The deployment of the arrays as well as the general health of the satellite were monitored by the ground station of the ISTRAC located in the Indonesian island of Biak. The Master Control Facility (MCF) at Hassan in Karnataka has since taken control of INSAT-4CR for all its post launch operations. Ground stations at Lake Cowichan (Canada), Fucino (Italy) and Beijing (China) are supporting MCF in monitoring the health of the satellite and its orbit raising operations.
In the coming days, INSAT-4CR’s orbit will be raised from its present elliptical GTO to the final Geostationary Orbit (GSO) by firing the satellite’s Liquid Apogee Motor (LAM) in stages. The satellite will be commissioned into service after the completion of orbit raising operations, checking out all its transponders and positioning it in its designated orbital slot of 74 degre
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