SRIHARIKOTA 2 Sep: The launch of the Geosynchronous Satellite Launch Vehicle, GSLV-F04, from here on Sunday turned out to be "a sweet success," with the launch vehicle lifting off flawlessly and injecting the communication satellite, INSAT-4CR, in its pre-determined orbit.
It was a remarkable comeback for the ISRO after the failure of the GSLV on July 10, 2006. It was the third consecutive successful mission this year.
On January 10, the PSLV put in orbit a spacecraft that was brought back to earth, and on April 23, a pared down version of the PSLV put in orbit Italian satellite Agile.
"A fantastic job"
ISRO Chairman G. Madhavan Nair said the ISRO team did "a fantastic job" after the failure of the GSLV mission in 2006. He appreciated "the precision with which this mission performed the job."
B.N. Suresh, Director, Vikram Sarabhai Space Centre, Thiruvananthapuram, described the launch as "a sweet success." It showed that the GSLV was a robust vehicle, whose systems performed as expected.
As Mr. Nair described it, "from all points of view, it was a highly dramatic mission."
The INSAT-4CR, at 2,130 kg, is the heaviest satellite to be launched by the Indian Space Research Organisation (ISRO). Its transponders would be used for direct-to-home telecast, video-picture transmission, telecasting news live using a satellite and business communications..
The GSLV-F04, a three-stage vehicle, is 49 metres tall and weighs 414 tonnes. The first stage is fired by solid propellants. There are four strap-on booster motors, powered by liquid propellants, strung around the core first stage. The second stage is fired by liquid propellants. The third, uppermost stage uses cryogenic fluids — liquid hydrogen as fuel and liquid oxygen as oxidiser. The vehicle was scheduled to lift off on September 1. But the heavy downpour on August 26 played spoilsport."Every night, clouds would come in from somewhere … There will be lightning. We lost 40 hours in the countdown sequence." So the launch was postponed to 4.21 p.m. on September 2.
But 15 seconds before lift-off at 4.21 p.m., there was a problem. The signal related to the readiness of the upper, cryogenic stage did not reach the computer, which takes over the entire launch sequence 12 minutes before lift-off. So the computer halted the launch. The problem was addressed and the launch re-scheduled for 6.20 p.m.
In the twilight hour, the GSLV-F04 shot off from its second launch pad at the Satish Dhawan Space Centre and rode a ball of flame. All the three stages ignited and jettisoned into the Bay of Bengal on time. Seventeen minutes after lift-off, INSAT-4CR was injected into the geosynchronous transfer orbit at a velocity of 37,000 km an hour.
The were other heartbreaking moments. There were signal drop-outs from the tracking stations at Brunei and Biak in Indonesia, and the ISRO lost track of the vehicle. This happened on and off for three and a half minutes. But at the end of 17 minutes, jubilation filled Sriharikota.
G. Ravindranath was the Mission Director and N. Jayachandran Nair was the Vehicle Director. Prahalada Rao was the Satellite Director.
Pat for scientists
PTI reports from New Delhi:
President Pratibha Patil, Vice-President Mohd. Hamid Ansari, Prime Minister Manmohan Singh and Lok Sabha Speaker Somnath Chatterjee congratulated space scientists on the successful launch.
This successful launch further validates the immense economic and strategic importance of the country's space programme, Mr. Ansari said. Mr. Chatterjee said the successful launch "proves the point that the GSLV is a reliable vehicle."
T.S. Subramanian
The Hindu
Tags: GSLV, Madhavan nair, vikram sarabhai, director, Insat-4CR, Satish Dhawan
--
Posted By auromarx to Astronomy and Telescopes India at 9/02/2007 10:11:00 PM
No comments:
Post a Comment