ISRO’s GSLV-D5: Why it was important for India?

Zee Media Bureau/Ajith Vijay Kumar New Delhi: It was dubbed as a game changer given the criticality of its success for future Indian space odysseys. Indian Space Research Organisation’s GSLV-D5 was all set to blast-off with GSAT-14 at 4.50 pm today before it was called off. The mission was aborted after a fuel leak was observed in the second stage of the vehicle which use hypergolic fuels as propellant. The mission objective was to place the 1,982-kg GSAT-14 satellite in the geo-synchronous transfer orbit after launch from the Satish Dhawan Space Centre at Sriharikota in Andhra Pradesh, 100 kilometers from Chennai. Prior to today’s attempt, the indigenous cryogenic stage in the GSLV-D3 mission on April 15, 2010 ended in a disaster after the thrust from the cryogenic engine failed to rev-up after lift-off. The GSLV was flown again in December the same year but this time round it used a Russian cryogenic stage. The mission too was a failure. And it is not just about the Rs 205 crore that the mission has cost the country; GSLV D-5 was and remains decisive for the long-term survival of India’s space programme. The 49.13 metre long GSLV D-5 was designed as a three-stage launch vehicle with a lift off mass of 414.75 tonnes. The first stage was to be propelled by solid fuel, the second liquid-propelled (with hypergolic fuels) and the final stage was to be propelled by cryogenic fuels - liquid oxygen and liquid hydrogen combination developing a thrust of 7.5 tonnes. The first and liquid stages being used in GSLV come from the tried and tested PSLV, giving ample reasons to worry to ISRO. Today’s launch was to be the eight launch of GSLV - the first six launches were carried out using cryogenic engines from Russia; the seventh in 2010 was indigenously built but had failed. Why is cryogenic engine so important? Cryogenic engines are needed to carry heavy payloads of up to five tonnes to geosynchronous transfer orbit - crucial for future telecommunication and space exploration – as against the 1.5 tonnes payload capacity of the PSLVs. The cryogenic technology is closely guarded by the countries that currently have it - USA, Russia, Europe, Japan and China. While Russia did come close to transferring the technology to India, it backtracked later albeit under pressure from Washington. Given our ever-growing need for bigger and better satellites, India was left with no choice but to go for indigenous development of cryogenic engines. Scientists and engineers at ISRO’s Liquid Propulsion Systems Centre (LPSC) at Mahendragiri, near Nagercoil in Tamil Nadu, took up the challenge and built India’s own cryogenic engine. Three years of research and development - after the India-made cryogenic stage failed in April 2010 – included making changes in its design and putting it through extensive tests. Now that the launch has been called off, it is back to the drawing board for ISRO.