Tag: cryogenic engine

GSLV D6 is a confidence booster

The GSLV Developmental-flight 6 launch by the Indian Space Research Organisation on August 27 was three things: the launch of the GSAT 6 satellite for the Indian military, the fifth successful launch of a GSLV rocket, and the second successful test-flight of the indigenous cryogenic upper-stage engine. The satellite is a two-tonne behemoth that’s too heavy for a PSLV rocket, whose maximum payload capacity to the geostationary transfer orbit is 1,410 kg, to heft – so the GSLV. And the cryogenic upper-stage enables the GSLV to lift a heavier payload: 2,500 kg to the geostationary transfer orbit.

But the most important takeaway lies in the big picture. This may be the fifth successful launch of the GSLV out of nine tries but it’s the second successive one. This may be the third successful flight with the cryogenic upper-stage but it’s the second successive one. And both accomplishments signify that ISRO’s scientists have been learning the right lessons from previous failures and that the GSLV is on the road to establishing reliability.

The previous successful test flight of the cryogenic engine was in January 2014, and the test before that in 2010 was a failure. While the PSLV rocket has four stages, of alternating solid and liquid ones, the GSLV Mk rockets that use the engine have three: solid, liquid and cryogenic stages. The solid stage is derived from the Nike-Apache engine of the US and the liquid stage, from the Vulcain engine of France. As a result of the extended legacies, it was easier for ISRO to adapt them for Indian rockets to use. However, the cryogenic engine had to be developed indigenously after the required tech. transfer from the Soviets fell apart in the 1980s due to political reasons.

With two successful flights in two years, the space agency now has reason to believe the engine could be finally past its teething troubles. And despite its intricate engineering, its success makes things simpler for ISRO. Before January 2014, ISRO was also considering a variety of Russian engines to power the GSLV Mk I’s and II’s upper-stage, all to no avail. Now it can focus on perfecting the cryogenic engine for the next big-picture milestone: at least two GSLV launches every year, signifying 4-5 tonnes equipment right there.

Note: This article was updated at 1.42 am on August 29, 2015, to say that the solid stage of the GSLV uses the S139 engine, not Nike-Apache, and that the liquid stage uses a modified Viking 4 engine, not the Vulcain.

A “Dear ISRO” moment

I published a quick analysis in The Hindu, republished with permission from Scienceline, about the ISRO Mars Orbiter. Gist (excerpted):

Even if [ISRO] has launched a spacecraft to Mars, the payload limit and the lack of an inclusive scientific agenda still stand in the way of taking full advantage of scientific interest and infrastructure on the ground.

These are some of the replies I received on Twitter in response to the piece.

You probably didn’t read my piece, and you probably don’t know what “one-hit wonder” means either.

Who are “Thomeses”?

I don’t understand why you think I’ve not been courteous. My arguments weren’t barbaric. And I think it’d be wonderful if people considered constructive criticism the utmost courtesy. I know I do.

A friend of mine recently told me he couldn’t criticize my piece for me because he said that’s not what friends do. But that’s what I think friends do do because appreciation that is completely honest is something very hard to come by.

This is a common blight plaguing the perception of scientific research in India. It’s easy to just say “nanosatellites” and then think about it inside your head. However, what’re they for? Who comes up with such ideas? Who builds them? And at the end of the day where would ISRO go with it? Answer them reasonably and then I’ll concede nanosatellites make sense.

Another aspect of this comment is that you’re thinking in terms of gee-whiz stuff, you’re thinking of demonstrating more technology, but ISRO is too important to indulge in things like that over and over again. It’s a national space agency so let’s be respectful of that.

Someone’s made an allegation and you’re batting it away. Do you know something that nobody else does?

Thanks.

Scienceline

I also received the following comments on the same piece as published on Scienceline (you should check the site out, it’s my NYU program’s science portal and has some other amazing pieces as well).

Thanks you for writing such a wonderful article to put the facts straight.Hope we don’t get overconfident as we have put only small payload of 15 kg whereas others have put 64 kg of payload. Hope a new mission to use GSLV-D5 to put more payload gets approved quickly and gets successful.Anyway achieving success on first maiden flight is no small feat and kudos to Indian Space scientists!!! – Ravikanth V

I’m glad you understand my sentiment.

Mr.Vasudevan, I don’t think you are a father. Only if you have become a father you can appreciate the baby’s steps in the beginning and that which ends even as an Olympic champion. But one has to go thru what is called growth. Hope you understood what I meant. – Bindo

Yeah, I get you, but I don’t want ISRO – nor the nation – to think of its interplanetary exploration program as it would of a child.

Dear writer, You crave attention so bad that, on the day of a historical achievement, you have published such a negative aticle. Shame on you. Have you designed any electronics before? And do you know how challenging is it to achieve that with limited budget? Please do not write such articles for ISRO. People of India take pride in this organization. You should have waited for atleast a day. – Kc

Because all my opinions are suddenly okay after 24 hours? And I think it is my duty as someone who does take pride in ISRO that I feel such things need to be said before we ramp up our expectations to heights the agency may never even have plans for.

Now it’s time for us to show our gratitude to the nation. Indians who are draining their brain to foreign countries, come back to our country as soon as possible. Finish ur commitments soon, ur nation has just made a history and waiting for you. – Dilip

I resent that you’re implying that all those who left the country in search of greener fields are/were opportunists. I also resent that you think the proverbial system is working well enough to be able to reject the oodles of talent still present in the country.

Very well articulated article, thank you. The mission is symbolic and demonstrates our ISRO’s scientific capability. I’m hopeful our new govt. will only be supportive of country’s scientific community, encourage with all means available and pragmatic enough to have or build a plan so, in a decade least, we indeed achieve what we want to be – equally a ‘space superpower’. Albeit this is still a proud moment for we the people of India. Congratulations to the ISRO’s scientific community who made this possible. – Guru Dwarakanath

Again, I’m glad you understand what I’m trying to say.