A PSLV C-39 rocket, carrying the IRNSS-1H navigation satellite, lifts off from the Satish Dhawan Space Centre in Sriharikota on August 31, 2017. The mission was unsuccessful

Chandrayan-II may also be launched in April, says ISRO Chairman

After its failure to inject into the orbit the eighth of the navigation satellite, IRNSS-1H that was to replace the faulty IRNSS-1A in the Indian Navigation Satellite Constellation or NavIC in August last year, the Indian Space Research Organisation (ISRO) is gearing up to launch another IRNSS satellite in April.

“The next launch will be in March end or April, but NavIC is already in full scale as four satellites are sufficient for navigation and we already have six. Adding more satellites, however, will guarantee better accuracy,” ISRO chairman K. Sivan told The Hindu on the sidelines of an ongoing International Conference on Sonar Systems and Sensors organised by the Naval Physical and Oceanographic Laboratory (NPOL), a Defence Research and Development Organisation facility.

Dr. Sivan said preparations were in full swing to ensure the success of the launch. He said the launch of Chandrayan-II would also take place in April subject to satisfactory integrated tests of the rover, lander and orbiter.

“The plan is to land on the moon’s south pole during the day and one moon day is 14 earth days. Which means we have this window of 14 days each month for the mission. But both the earth and the moon are moving. Hence the question of visibility and varying power requirements. As for the mission, the orbiter, lander and the rover are getting ready as individual missions. They should be integrated and tested. Since it is a maiden attempt for us, there’s some uncertainty. Therefore, just in case something needs an upgrade and we miss this clear visibility window in April, our next chance will be in October. But the activities are in full steam targeting April,” he said.

An expert in launch vehicles, Dr. Sivan said the space agency was also working towards developing a hypersonic reusable launch vehicle technology demonstrator that should be ready in a year or two. “Our RLV is different from what other people have done. We are having a winged vehicle so that it can return to land or shore. Also, after injecting the payload, it will fly like an aircraft. To do this, many technologies are to be mastered. One is a high velocity flight and when it returns from the orbit, it should be shielded from extreme temperatures. And, it is to land autonomously. In the 2016 flight, one such technology was demonstrated. Now, we must demonstrate this return from the orbit and autonomous landing. We will do that in one or two years,” he said.

On the GSLV Mark III, Dr. Sivan said attempts would be made to increase the launch vehicle’s payload carrying capacity – four tonnes at the moment – with each forthcoming flight. “We are adding an additional 600 kg payload with each of its flights.”