'Rocket launch is always a risky business'

'It is a blessing in disguise that they could find the glitch before the launch.'
'If this was not found, the entire mission would have been lost.'

Monday, July 15, 2019, was to be a red letter day in the annals of India's space programme, when Chandrayaan 2, India's second mission to Moon, was to be launched at 2.51 am on board GSLVMkIII-M1.

But following 'technical glitches,' the countdown was stopped at 1.55 am, just 56 minutes and 24 seconds before the rocket was launched.

'A technical snag was observed in the launch vehicle system at t-minus 56 minutes. As a measure of abundant precaution Chandrayaan 2 launch has been called off for today,' ISRO Associate Director (Public Relations) B R Guruprasad said, adding, 'Revised launch date will be announced later.'

This was the second time the launch has been postponed, The first, scheduled for January this year, was also called off.

The Chandrayaan 2 mission is a follow-up of Chandrayaan 1 that helped confirm the presence of water/hydroxyl on Moon in 2008.

"Since we are going to the Moon's South Pole, it has to be precisely timed in such a way that the arrival time on the Moon is specified, as the orientation of the Moon is important. So, if we miss this opportunity, the next opportunity will come only in September," former ISRO chairman G Madhavan Nair tells Rediff.com's Shobha Warrier.

When something like this happens, how does the mood among all those who have been planning it for so long, change?

Rocket launch is always a risky business. Anything can go wrong at any time. Everybody associated with rocket launches keeps that in mind.

If you take the experience of not just India but other countries too, some of the failures have happened on the launch pads, some have happened in the flight and some in the final stages of the orbit.

How often have the failures happened? 

If you take the global average, the success rate is 90%. It means 10% of the efforts have failed at various stages.

But the Indian track record is slightly better. Our failure rate is just 5%, which is a very good record.

This time, the failure happened during the countdown process.

The fact that it was detected by the ground support system shows the success of our technology. It gave us a warning, and based on the warning, they stopped the launch.

It happened less than an hour before the launch was to take place...

Yes, in the case of Chandrayaan 2, the countdown started 20 hours before the launch.

The last minute operations of every instrument connected with the launch would be checked during the countdown and they are precisely timed.

This was to continue for 20 hours and at the end of that, we would press the button for the launch.

The countdown time depends on the complexity of the mission and it can vary from one hour to two hours to even two days.

This time, during the countdown of the final operations, pressure drop was observed in one of the high pressure gas bottles which were to be on board.

The pressure drop could be due to many reasons. So, we have to pinpoint where exactly the leak is and what is the nature of the leak and then take appropriate corrective action before the rocket is launched.

That is the course we are in now. It could be done over a day or a week...

As far as the Chandrayaan mission is concerned, we are a bit constrained about the launch date.

Since we are going to the Moon's South Pole, it has to be precisely timed in such a way that the arrival time on the Moon is specified, as the orientation of the Moon is important.

So, if we miss this opportunity, the next opportunity will come only in September.

Is it because of the position of the Moon?

Yes, it has to be positioned in such a way that we can land at the South Pole.

Anyway, I understand that they are working on the problem, and in a day or two we will have a clearer picture.

We have time till the end of July. But if we miss that, then we will be able to do it only in September.

It is for the first time that somebody is going to land on the South Pole of the Moon. No other country has gone there. How important is this for India?

Yes, the (Moon's) South Pole is a totally unexplored territory. So, it is a very ambitious mission to go there, collect samples and come back.

We are going to land a set of instruments on the surface of the moon and it is important that they survive the conditions.

We are going to have a soft landing process. In fact, the soft landing technology is available only with the USA, Russia and China. We become the fourth nation to use this technology.

So, it is a very unique achievement looking at the technology to be used in the lander, the rover that is to move around on the moon to collect samples.

Once we get samples from Chandrayaan 2, we will be able to scientifically study the data and confirm the water content availability quantitatively and also look for the presence of helium, the fuel for the future.

Why did India decide to explore the South Pole of the Moon?

That region is not much affected by solar radiation and the availability of water is better in the polar region. That was why we have selected South Pole of the Moon.

During your time as ISRO chairman, some launches have failed. How do you get over the feeling of disappointment after going through all the excitement?

We recognise the fact that there are risks involved in the launches. Failures can happen and they are not uncommon.

From that point of view, we are prepared to face any eventuality.

Yes, there will be disappointment and dissatisfaction, but normally these emotions will not last long.

The logical thinking and analytical capability of the team will be triggered much more vigorously after a failure and that leads to appropriate solutions.

The feeling is so strong to see that the problem does not occur again which we have demonstrated in several missions starting from the first SLV and later the PSLV and recently the GSLV Mark 2.

The GSLV Mark 3 had a fairly good record of last two perfect launches and there is no reason to believe that anything would go wrong in this mission.

So, it is a blessing in disguise to have caught something before the launch.

What was your feeling when you heard about the technical glitch?

That it is a blessing in disguise that they could find the glitch before the launch.

If this was not found, the entire mission would have been lost.

Because we caught it before the launch, we got a chance to correct it and aim for a perfect mission.

When you solve most of the problems from the ground, you will have less problems on flight, then you will have more confidence on the flight.

Between Chandrayaan and the Mars Mission, which is more important for India?

In the 10-year period, programmes for the Moon and Mars are equally important.

We have a had a head start in Chandrayaan and the mission will be of great importance to India.

In the long-term goal, Mars also becomes important.

Of course, we need powerful rockets and better payload for the Mars exploration as the Mars Orbiter Mission carries five payloads.