India's Geo-synchronous Satellite Launch Vehicle (GSLV-F06) is all set to lift off from Sriharikota at 4 p.m. on December 20 to put a communications satellite called GSAT-5 Prime in the orbit 19 minutes later. The 30-hour countdown will start at 10 a.m. on December 19. The satellite has been mated with the vehicle.
The GSLV-F06 has three stages, with the first core stage powered by solid propellants. There are four strap-on booster motors, fuelled by liquid propellants, strung around the first stage. The second stage uses an engine that is powered by liquid propellants. The third upper cryogenic stage is from Russia. The GSAT-5P weighs 2,300 kg.
P.S. Veeraraghavan, Director, Vikram Sarabhai Space Centre (VSSC), Thiruvananthapuram, said the Russian cryogenic stage is “an upgraded version, which is more powerful” than those used in the previous GSLV missions. “So we are going for a higher payload of 2,300 kg. I think this is the heaviest payload to be put in orbit by a GSLV.” Two important activities will take place during the 30-hour countdown. While the second stage and strap-on boosters will receive the liquid propellants beginning T-minus 30 hours, the cryogenic propellants — liquid hydrogen and liquid oxygen in extremely low temperatures — will be pumped into the upper Russian cryogenic stage only from T-minus six hours, Dr. Veeraraghavan said.
S. Satish, Director of Publications and Public Relations, Indian Space Research Organisation (ISRO), said the GSAT-5P would “provide continuity to services already offered by the INSAT system.” It has 36 transponders, including 24 C-band transponders and 12 extended C-band ones. The transponders will be useful in telecasting television programmes, including those related to telemedicine and tele-education and in boosting telephonic services, Mr. Satish said.
“The satellite will increase our transponder capacity. That way, it is a crucial mission for us,” said Dr. Veeraraghavan.
The mission will last 1,140 seconds, at the end of which the cryogenic stage will catapult the GSAT-5P into the orbit. ISRO Satellite Centre, Bangalore, has built the GSAT-5P.
This is the sixth GSLV mission that will use a Russian cryogenic engine. The GSLV weighs 414 tonnes and is 49 metres long.
The former President, A.P.J. Abdul Kalam, will pay a visit to the facilities at the spaceport at Sriharikota on December 17 and meet ISRO's launch vehicle technologists. A rocket technologist himself, Mr. Kalam was the Project Director of ISRO's SLV-3 flights from Sriharikota in 1979, 1980 and 1981 and later became a missile technologist.