Rajeswari Pillai Rajagopalan
04 January 2014
After two successive failures of its Geostationary Launch Vehicle (GSLV) launches in 2006 and 2010 and an aborted mission in 2013, India's endeavour to launch another GSLV on January 5 is being watched with both hope and apprehension. Though the Indian Space Research Organisation (ISRO) has done several trial tests for the launch of GSLV-D5, there is apprehension because of what happened in 2010 and 2013.
A successful launch of GSLV will place India in the same league as a handful of countries as far as the technological sophistication is concerned. Currently, there are five countries - the United States, Russia, France, Japan, and China - that have demonstrated the cryogenic engine upper stage technology in order to launch heavier satellites in geostationary orbit. India will become the sixth nation to design and develop this sophisticated and complex technology. The GSLV-D5 rocket will carry on board the 2-tonne GSAT-14 satellite capable of delivering communication services in the area of tele-medicine and tele-education. On December 28, 2013, the Mission Readiness Review (MRR) team and the Launch Authorisation Board (LAB) cleared the GSLV-D5/GSAT 14 launch for January 5 and thereafter the rocket was shifted to the launch pad.
The three-stage rocket, with solid, liquid and cryogenic stages, is "a very complex system compared with solid or earth-storable liquid propellant stages due to its use of propellants at extremely low temperatures and the associated thermal and structural problems", according to the ISRO. Cryogenic technology is significant because the thrust gained through burning every kg of propellant is far higher in a cryogenic engine, which gives the thrust to carry heavier payloads into orbit.
Starting in April 2001, India has so far carried out seven GSLV launches, including three failures and one aborted launch. Past failures have included problems such as deviation from the predicted flight paths soon after the lift-off. The attempt in 2013 had to be called off hours before the lift-off as they detected a leak in the fuel tank of the liquid second-stage in pre-launch pressurisation phase of the vehicle.
This time around, ISRO Chairman Dr. S Radhakrishnan and the engineers appear confident of having rectified many of the problems faced in the previous missions. There have been several committees set up to study in detail the cause of failures and accordingly remedial measures have been taken. For instance, they have used an entirely new fuel tank. Apparently, the earlier leaked-prone fuel tank was an old stock, procured four years ago and also the aluminium alloy, Afnor 7020 that was used in the making of the tank tends to develop cracks over a period of time. The booster turbo pump, that ran into problem twice previously, had used different materials that contracted differently at low temperatures, which has been rectified now by using a single material. Similarly, the issues of contamination with the propellant acquisition device procured from Russia have been addressed and this time around, the device is manufactured in India. There has been refurbishing of the casing of the rocket as well.
Tomorrow's attempt will be significant both from the commercial and strategic perspectives. In addition to the large number of domestic satellites ready to be launched using the heavier launch vehicle, a successful launch will also mean India's ability to cash in on the large lucrative foreign satellite launch market.
Given the ever-increasing reliance on space assets for a variety of missions from socio-economic and development to military functions, the number of satellite launches will spike significantly in the coming years. China has already captured a sizeable chunk of this market even though India offers much more cost-effective launches, which in fact have been its strength.
India's tried and tested Polar Satellite Launch Vehicles (PSLV) have a weight limitation of just over one tonne. A PSLV is capable of carrying 1600 kg satellites in 620 km sun-synchronous polar orbit and 1050 kg satellite in geo-synchronous transfer orbit (GTO). A GSLV on the other hand will offer India ability to launch satellites weighing 3.5-5 tonnes.
A successful launch with the indigenous cryogenic engine will go a long way in making India self-sufficient in the area of satellite launching. Large tonnage carrying capability is important in the domestic context since it will no longer have to depend on foreign rockets to carry their large satellites. Chandrayaan-2 is a case in point. Other satellite launches planned include GSAT-6A and 7A, two remote sensing satellites, GISATs and the GSAT series including GSAT-9. Relying on foreign carriers has had reliability issues in addition to the cost factor as these have proven to be more expensive options.
(Dr. Rajeswari Pillai Rajagopalan is a Senior Fellow at Observer Research Foundation, Delhi. Her research ares include space and security)
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