 "ISRO successfully launches GSLV-D6 carrying GSAT-6 satellite")
The successful launch is another feather in the Indian space agency's hat as getting the cryogenic engine right is important for India's future space programmes, said experts. Isro scientists spent nearly two decades in conceiving and mastering the cryogenic technology. Around Rs 400 crore was spent on developing the technology. A cryogenic engine is more efficient as it provides more thrust for every kilogram of propellant burnt.
"It is a result of tremendous amount of hard work put in by the entire team to build in an indigenous cryo engine and today's performance of the launch vehicle clearly demonstrates that all the systems have been performing very normally and the various intricacies of the cryogenic engine performance and the systems have been understood," said A S Kiran Kumar, chairman, Isro, after the successful launch.
It may be noted that in February 2014, ISRO for the first time conducted the successful launch of indegenous cryogenic engine backed GSLV. For Kumar, this is the first successful GSLV rocket launch as ISRO chief that placed a satellite in orbit.
The next GSLV launch will be in June or July next year. ISRO has set a target of two GSLV launches every year.
Currently, India's heavy communication satellites are launched by an European space agency Ariane and the success of GSLV would help the country to save huge foreign exchange. India spends nearly $85-90 million (around Rs 500 crore) as launch fee for sending up a 3.5 tonne communication satellites, apart from the cost of satellite.
The 49.1 metre, weighing 416 tonne tall rocket blasted off at 4:52 pm and successfully completed the mission in 17 minutes from launch. It may be noted current GSLV rocket of Isro's can carry a capacity of around 2.2 tonnes.
The rocket carrying the cuboid shaped GSAT-6 communication satellite weighing 2,117 kg slung it in GTO around 17 minutes into the flight. The whole mission concluded in the exact way it was envisioned.
GSLV-D6 is the ninth flight of India's Geosynchronous Satellite Launch Vehicle (GSLV). It is also the fifth developmental flight of GSLV. This is the third time the indigenously developed Cryogenic Upper Stage (CUS) is being carried on-board during a GSLV flight. GSLV-D6 flight is significant since it intends to continue the testing of CUS. GSLV is designed to inject 2 ton class of communication satellites into Geosynchronous Transfer Orbit (GTO).
This is the second time Isro flew the GSLV rocket with its own cryogenic engine, after the successful launch of similar rocket in January 2014 that put into orbit GSAT-14. It may be noted the second mission of GSLV during the last five years after two such rockets failed in 2010. One of the GSLV rockets flew with Indian cryogenic engine and the other one with a Russian engine.
ISRO's communication satellite GSAT-6 on board GSLV-D6
The GSLV is a three-stage rocket. The core of first stage is fired with solid fuel while the four strap-on motors by liquid fuel. The second is the liquid fuel and the third is the cryogenic engine, said experts. India spends nearly $85-90 million (around Rs 500 crore) as launch fee for sending up a 3.5 tonne communication satellites. The cost of satellite is separate.
ISRO can send smaller communication satellites, around two tonnes, till such time it gets ready an advanced GSLV variant-GSLV-Mark III- that can lug satellites weighing around four tonnes, they added.
Isro is planning to launch satellites like GSAT-7A, 9 using a similar rocket.
GSAT-6 is India's 25th geostationary communication satellite and twelfth in the GSAT series including one in 2001, 2003, 2004, 2007 and 2014 respectively.
Five things to know about GSAT-6
1) GSAT-6 will join the group of India's other operational geostationary satellites and it will provide communication through five spot beams in S-band and a national beam in C-band for strategic users.
2) The S-Band Unfurlable Antenna of six metre diameter is one of the advanced features of GSAT-6 satellite
3) This is the largest satellite antenna realised by ISRO and it is utilised for five spot beams over the Indian main land
4) Spot beams exploit the frequency reuse scheme to increase frequency spectrum utilisation efficiency.
5) The satellite's life expectancy is nine years.