Indian Space Programme Discussion

Austin · Post by **Austin** » 18 Dec 2014 11:01

Congratulation ISRO and GSLV Team

ashish raval · Post by **ashish raval** » 18 Dec 2014 11:32

Congratulations to ISRO and country men. Nice end of the year. Champagne time

....

Vivek K · Post by **Vivek K** » 18 Dec 2014 11:32

Great job!

vina · Post by **vina** » 18 Dec 2014 11:39

I was looking at the launch video posted by Suraj (didn't watch it live) and at around 26mins or so, Dr Radhakrishnan, the English commentator said what I wrote a few pages ago, when I said the GSLV III as of now is rather inefficient. He repeated the same mass fraction of lift off mass calculation that I used and made the following observations

1) The PSLV's mass fraction is around 0.4%
2) The GSLV 1/2 is around 0.5%
3) The GSLV MKIII is around 0.6% (same number that i posted earlier).

The performance of the best in class (which will be all high performance liquids) (we will leave out the Japanese exotics like all cryogenic H2 etc) is probably the Atlas V with a mass fraction of 1.4% .

So, if the WeakAss(es) are replaced, we will get it up to around 1% mass fraction or roughly 6.6 tons to GTO. It won't go much north of that, will get to at best 1.2% (around 8 tons) after all optimisations , with those solid stages which have a low Isp. That is okay. It will be cost effective and pretty effective launcher even in that config.

deejay · Post by **deejay** » 18 Dec 2014 11:40

Awesome! Great news and Well Done ISRO!!!

Suraj · Post by **Suraj** » 18 Dec 2014 11:40

Thanks, vina.

member_27164 · Post by **member_27164** » 18 Dec 2014 11:41

wasu wrote:Got any pictures, aditya?

Oh I am sorry for your misunderstanding. I meant saw it live on TV.
If possible I would be happy to stand right below or at the tip of the rocket to get photos.

Indranil · Post by **Indranil** » 18 Dec 2014 11:46

vina wrote: It is not thrust alone, but the efficiency that matters. The semi cryo will have specific impulse of 330 to 360 s, while the best L110 can get to is 270s. That is a good 60s increase in specific impulse. Even if you replace the L110 with a semi cryo with the exact same thrust, the mass fraction (the final mass that gets taken to orbit) will see a dramatic improvement because of higher efficiency (all else being the same).

The only thing that can be done is to make the cryo stage fire longer and cut down the size of the L110. That is not optimal either, from a configuration and cost stand point.

What else is the ULV, but LVM 3 with the SC160 instead of L110? It will be able to lift 6.2T to GTO i.e. a mass fraction of 0.9 (against 0.65 of LVM 3). They are getting there. Today they jumped from 0.4 to 0.65. Let's rejoice it.

member_28911 · Post by **member_28911** » 18 Dec 2014 11:47

What's with the obsession of optimization and efficiency? Please compare the cost/kg to GTO of different launch vehicles to get the real picture.

brat · Post by **brat** » 18 Dec 2014 12:07

Congratulation ISRO and All

Indranil · Post by **Indranil** » 18 Dec 2014 12:13

Ankar wrote:What's with the obsession of optimization and efficiency? Please compare the cost/kg to GTO of different launch vehicles to get the real picture.

The cost of what Vina is suggesting is going to be lower. With GSLV we were paying Rs 10,00,000 per kg. With LVM 3, this is expected to come down to Rs 5,00,000 per kg. With ULV this number is supposed to go down even further (but not by much).

member_28108 · Post by **member_28108** » 18 Dec 2014 13:46

Till the cryogenic engine Iis standardized we have to use what we have. As things develop there will be improvements. At least we are validating what we have developed so far. These will all be stepping stones. No point cribbing about what we don't have. If we had only focussed on cryo- semi cryo we would not have achieved what has been done so far and pure entire program would have stalled on hitting a road block. Let us not forget only a half a dozen countries have the knowledge wherewithal and capability. We are getting there and we should stand by our scientists who have achieved a lot with whatever budgetary constraints etc that they have.

member_28108 · Post by **member_28108** » 18 Dec 2014 14:03

Deleted duplicate

Supratik · Post by **Supratik** » 18 Dec 2014 14:28

congrats.

Narad · Post by **Narad** » 18 Dec 2014 14:34

Great Job !!!

vina · Post by **vina** » 18 Dec 2014 14:44

What's with the obsession of optimization and efficiency? Please compare the cost/kg to GTO of different launch vehicles to get the real picture

So why don't you do that cost/kg comparison and post. And while you are doing that consider a more "pill-o-so-ical" point here , which is more in the realm of Nukkad and economic threads than here . So take it there and you can discuss how to arrive at the "competitive cost".
In the immortal worlds of Mullah Enqyoob, (who is now more in to herding yaks than issuing fatwas) ,

Al Managers exhort that "We should think strategically and execute tactically , and whip them hard and feed them poo"

If that is the kind of society overall (if you don't focus on productivity) you wish for and what you will be feeding the ISRO folks in particular (in terms of wages), sure, do the bloat thing.

nirav · Post by **nirav** » 18 Dec 2014 15:37

indranilroy wrote:
Ankar wrote:What's with the obsession of optimization and efficiency? Please compare the cost/kg to GTO of different launch vehicles to get the real picture.
The cost of what Vina is suggesting is going to be lower. With GSLV we were paying Rs 10,00,000 per kg. With LVM 3, this is expected to come down to Rs 5,00,000 per kg. With ULV this number is supposed to go down even further (but not by much).

The LVM 3 has barely made its first experimental flight. will take another 2 years or so before it can be declared operational.

So mid way, after putting in all the hard work ,ISRO should junk the Vikas engines for semi cryos which btw haven't been realized yet ..

All this for MOAR "mass fraction" and because Vikas engines are now suddenly WeakAss.

After a point, such "suggestions" start becoming insulting to the massive effort ISRO puts in .. so does calling the engines as WeakAss.

Would request posters to desist from showing their excellent wordplay skills .. its not funny !

akashganga · Post by **akashganga** » 18 Dec 2014 15:45

Congratulations ISRO for GSLV MK3 launch. This has been a successful year for ISRO. Looking forward to another great year for ISRO. Cheers.

Hemanth · Post by **Hemanth** » 18 Dec 2014 15:49

Missed the live telecast; any youtube videos out there?

My hearty congratulations to ISRO family.

EdiT:

Found a couple of videos in youtube. Yeah, the DD cameraman messed up the treetop view.

Comer · Post by **Comer** » 18 Dec 2014 15:59

Is the crew capsule recovered yet?

member_28108 · Post by **member_28108** » 18 Dec 2014 18:20

deejay · Post by **deejay** » 18 Dec 2014 18:25

^^^ That is a wonderful set of pictures.

shravanp · Post by **shravanp** » 18 Dec 2014 18:54

Super congratulations to ISRO team! KHatarnaak performance.

Those images hit the spot!

raj-senthil · Post by **raj-senthil** » 18 Dec 2014 19:11

Yes. ISRO website have pictures of them

http://isro.org/gslv-mkiii-x/Imagegalle ... cle.aspx#0

saravana wrote:Is the crew capsule recovered yet?

kmc_chacko · Post by **kmc_chacko** » 18 Dec 2014 19:19

Congrats ISRO

member_28108 · Post by **member_28108** » 18 Dec 2014 19:20

member_28108 · Post by **member_28108** » 18 Dec 2014 19:22

The tiles look really good and do not look scorched like we see the Soyuz/Apollo and Shenzou reentry capsules. I cannot see the buoys/flotation devices.Wonder how it is floating.

member_28108 · Post by **member_28108** » 18 Dec 2014 19:30

member_28108 · Post by **member_28108** » 18 Dec 2014 19:35

What are those two ropes and small white things that are floating near the main capsule and appear to be taut

Comer · Post by **Comer** » 18 Dec 2014 19:35

raj-senthil wrote:Yes. ISRO website have pictures of them

http://isro.org/gslv-mkiii-x/Imagegalle ... cle.aspx#0

saravana wrote:Is the crew capsule recovered yet?

Nice! Thanks. Hoping this too get validated.

SagarAg · Post by **SagarAg** » 18 Dec 2014 19:38

Congratulations ISRO and all the people involved. Bharat Mata Ki Jai!

rgsrini · Post by **rgsrini** » 18 Dec 2014 19:55

Great Job ISRO. Congrats!!!

Question for gurus.

Before

After

Hmmm... Did it lose the top on the way down, or is this as per design? The exposed aluminum structure seems to be covered with a tiled enclosure. Hence my question...

rsingh · Post by **rsingh** » 18 Dec 2014 19:56

prasannasimha wrote:

First and last pic shows the amazing cloud formation in the background..........as if mother nature herself visited the place to congatulate isro. This is the pic of year for me.what an pic. I remember an Indian scientist who worked for esa (based in Brusselabad) taunted me saying that India can not launch big sattelites.

member_28108 · Post by **member_28108** » 18 Dec 2014 20:00

rgsrini that top thing was to blow off to deploy the parachutes .If you see the original module you can see the joint line at that point.

shaun · Post by **shaun** » 18 Dec 2014 20:03

Two videos sourced from nasaspaceflight.com forum http://forum.nasaspaceflight.com/index. ... =15187.600

[youtube]https://www.youtube.com/watch?v=KvmdGxi4ahM[/youtube]

[youtube]https://www.youtube.com/watch?v=5uOaTpzBQEY[/youtube]

rgsrini · Post by **rgsrini** » 18 Dec 2014 20:08

Thanks for the confirmation prasannasimhaji. Do you know what the 2 holes and the big marshmallow on the top as well. I hope the heroes of ISRO publishes a detailed write up on the crew module and the experiments conducted in this iteration.

Shalav · Post by **Shalav** » 18 Dec 2014 20:28

prasannasimha wrote:The tiles look really good and do not look scorched like we see the Soyuz/Apollo and Shenzou reentry capsules. I cannot see the buoys/flotation devices.Wonder how it is floating.

Floating because of displacement, like normal sea going vessels.

Flotation devices were added to manned capsules after the second US manned mission's capsule Liberty Bell 7 sunk due to an inadvertent early release of the crew hatch. It is a safety measure to keep the capsules afloat even if there is a breach in the capsule. I suppose they will add those in the next flight test along with a crew hatch, which I did not notice either. This was a TD to validate reentry technologies.

member_28108 · Post by **member_28108** » 18 Dec 2014 20:39

Shalav wrote:
prasannasimha wrote:The tiles look really good and do not look scorched like we see the Soyuz/Apollo and Shenzou reentry capsules. I cannot see the buoys/flotation devices.Wonder how it is floating.
Floating because of displacement, like normal sea going vessels.

Flotation devices were added to manned capsules after the second US manned mission's capsule Liberty Bell 7 sunk due to an inadvertent early release of the crew hatch. It is a safety measure to keep the capsules afloat even if there is a breach in the capsule. I suppose they will add those in the next flight test along with a crew hatch, which I did not notice either. This was a TD to validate reentry technologies.

I also assumed so but SRE1 had a flotation ring etc and was assuming they would have one for this too.

member_28108 · Post by **member_28108** » 18 Dec 2014 20:42

I was wondering why they did not add a crew hatch and portholes etc a the integrity of these had to be tested anyway.Probably would do so once the basic structure was validated.

Shalav · Post by **Shalav** » 18 Dec 2014 20:46

rgsrini wrote:
Before

Do you mean the white ring on the black reentry tiles? It could just be damage protection looks like..