India’s Heaviest Rocket Set For Launch

The countdown for India’s heaviest rocket – Geosynchronous Satellite Launch Vehicle-Mark III (GSLV-Mk III) – is well under way. It is set for its maiden flight into space along with a communications satellite GSAT-19 on Monday evening.

Indian Space Research Organisation (ISRO) will launch its heaviest rocket, the 640-tonne Geo-synchronous Satellite Launch Vehicle (GSLV) Mark-III, from the Satish Dhawan Space Centre in Sriharikota. The rocket, weighing 640 tonnes and standing 43.43 metres tall, will blast off from the second launch pad at India’s rocket port at Satish Dhawan Space Centre in Sriharikota. Indian Space Research Organisation (ISRO) said the mission’s success will enable India to launch four-tonne satellites on its own rocket instead of paying huge amounts of money to foreign space agencies to execute the operation.

Although India has one of the most advanced spaces programmes on the planet and has been a space-faring nation for over 50 years, it has had to depend on others for the launch of its larger satellites to the Geosynchronous Transfer Orbit (GTO). Most recently, India used a heavy-duty rocket of Arianespace, world’s first commercial launch service provider, for placing communication satellite GSAT-18 into the GTO. India’s most capable launch vehicle until now, the GSLV Mark-II, is capable of launching payloads of only up to 2.2 tonnes into the geostationary orbit. However, the GSLV Mark-III will allow India to place satellites as heavy as 4-tonnes into the GTO. The maximum payload limit for the GSLV Mark-III is 60 per cent greater than that for the GSLV Mark-II.

This launch is also important because the GSLV Mark-III will be India’s first fully functional rocket to be tested with the indigenously developed CE-20 cryogenic rocket engine that uses liquid propellants – liquid oxygen and liquid hydrogen. Liquid fuels are more desirable as they are less bulky than solid ones and flow better than gaseous fuels. Also, when hydrogen burns in the presence of oxygen, the exhaust velocity (velocity at which exhaust gases leave the nozzle of the rocket’s engine) is 4.55 km/s. This is significantly higher than exhaust velocity of other fuels. For example, when unsymmetrical dimethylhydrazine, which fuels Polar Satellite Launch Vehicle’s Vikas engine, burns in the presence of nitrogen tetroxide, the exhaust velocity is 3.42 km/s.


Source: Swarajya