ISRO proved beyond doubts its cryogenic expertise after the successful GSLV-D6 mission which took 17 minutes to deliver the GSAT-6 spacecraft into orbit.
In yet another spectacular “space show”, Bharat’s Geosynchronous Satellite Launch Vehicle (GSLV), powered with a home-grown upper cryogenic engine stage, placed GSAT-6 advanced communications satellite into its intended orbit with a “text book precision.”
The August 27 successful GSLV-D6 mission which took 17 minutes to deliver the GSAT-6 spacecraft into orbit, after its majestic lift-off from the second launch pad of Satish Dhawan Space Cetre (SDSC) in Sriharikota island, has once again proven to hilt the functional efficiency and operational robustness of the indigenous cryogenic engine stage symbolising the two decades long painstaking endeavours of Bharatiya space scientists. This is the second successful flight of 416 tonne heavy GSLV with a domestically built cryogenic engine stage. According to the Indian Space Research Organisation (ISRO) a cryogenic propulsion system is highly efficient since it produces more thrust per unit of propellant burnt in comparison to solid and earth storable liquid propellants. Verily, in terms of boosting launch capability, GSLV implies a quantum leap for the Bharatiya space programme.
The mission objective of GSLV, capable of launching a satellite payload weighing upto 2.5 tonne into the geostationary transfer orbit, is to free Bharat from its dependence on procured, commercial launch service for orbiting its GSAT/INSAT series satellites in 2-2.5 tonne weight class. On the one hand, the deployment of GSLV for routine orbital missions would save Bharat a huge amount of foreign exchange involved in paying for the hired commercial space launch services. On the other hand, the Bengaluru-based Antrix Corporation, the commercial arm of the Bharatiya space programme, can promote GSLV as a cost efficient commercial space vehicle for orbiting the satellite payloads of international customers and earn for the country the much needed foreign exchange. As it is, Bharat has already made modest forays into the multibillion dollar, global market for launching satellite by pressing into service the four stage, reliable space work horse, Polar Satellite Launch Vehicle (PSLV) as a cost efficient vehicle for delivering light weight satellite payloads into a variety of orbits. PSLV has so far launched 45 satellites of 19 countries on commercial terms with a high degree of precision and reliability.
Having mastered the challenging cryogenic engine technology, ISRO will now be in a position to build better and bigger launch vehicles by just scaling up the proven technology. In a way, ISRO has overcome the technological barrier in so far as boosting the launch capability is concerned by demonstrating the efficacy of the cryogenic engine technology through two consecutively successful GSLV flights powered by the indigenous cryogenic engine stage. Meanwhile, ISRO is preparing the ground for the maiden, full-fledged flight of the 630 tonne heavy lift GSLV-MKIII capable of delivering a four tonne class satellite into a geostationary transfer orbit sometime before the end of next year.
Now about the unique features of GSAT-6 satellite. An advanced high powered S-band satellite with a lift off mass of 2117 kg, GSAT-6 is the twenty fifth geostationary communications satellite built by ISRO. The potentials of GSAT-6 will be harnessed by the Bharatiya Defence forces for “strategic purposes”. In addition, the satellite will be used for disaster management and emergency response. The satellite is designed for providing communications through five spot beams in S-band and a national beam in C-band for strategic users. One of the advanced features of GSAT-6 is its S-band unfurlable antenna of 6-m.diamter. This is the largest satellite antenna ever realised by ISRO. The inputs provided by GSAT-6 would enable ISRO to build multimedia communications satellite with futuristic technological elements.
But more than anything else, the message of GSLV-D6 mission is: however complex and challenging a technology might be, Bharat is fully well capable of mastering it. On another front, the success of GSLV stands out for its robust defiance of the technology denial regime spearheaded by US which is far from comfortable about Bharat’s technological strides.
Overcoming all the hurdles and challenges, ISRO proved its excellence in realising a cryogenic propulsion system whose superb performance has been established beyond any shadow of doubt. Indeed, the meaning of the GSLV mission is that Bharat is poised to strengthen its leadership position in space.
Radhakrishna Rao (The writer is a freelance columnist who writes on science tech and defence related issues)
