Indian Space Program Discussion

member_23694 · Post by **member_23694** » 09 Sep 2012 12:23

congrats ISRO for another routine and successful launch....very much expected...

Now please launch the GSLV with Indian Cryo and GSLV MARK 3 - TD by year end ..... can't wait for those

SSSalvi · Post by **SSSalvi** » 09 Sep 2012 15:24

pentaiah wrote:congrats to all the ISRO personnel

one question Mauritius is west south west of Shrihari kota, and I guess the rocket is launched east wards why is that after launch Maritius is confirming the tracking should be east south east of India no?

I think the reference to Mauritus that is being mentioned is to the announcement " Mauritius confirms ..... " during launch.

What the announcement means is that " Mauritius tracking station has confirmed ... ".

There are some tracking stations around the world which are used to track all international launches. This is required because the satellite that is being launched can't be in direct visibility contact with launching site / control station. So these relay stations track the satellite/rocket whenever it is visible over their area and send Telemetery data to Control Station for it to take necessary action if required.

Mauritius is one of such station used by not only ISRO but all launch agencies. This is a international network.

===============

vina's suggestion is very innovative indeed but may have implications on international relations.

nakul · Post by **nakul** » 09 Sep 2012 15:32

It will be much easier to build a small station on the southern coast of Sri Lanka. It is on an latitude close to that of French Guyana. It will not only be much closer to India but also be used as a stepping stone towards closer India - Sri Lanka relations.

abhishek-nayak · Post by **abhishek-nayak** » 09 Sep 2012 16:54

Congrats to all for this stupendous mission but i have a few questions:-

1) what is the status of SRE-2 ?

2) when is GSLV 3 planned for test launch ?

3) Has the construction of mars satellite started?

D Roy · Post by **D Roy** » 09 Sep 2012 17:29

if Manmohan wants to leave a legacy of having supported science and technology, he doesn't have much to show for it.

In the past 8 years what we have seen is ISRO failing to take it to the next level as it hasn't yet managed to get the GSLV Mk-II up to speed and the date for the Mk III has got pushed forward time and again.

is becoming completely self-sufficient in launch vehicle technology not the the chief aim anymore? has something changed?

I usually never make these kinds of posts especially on a day when we celebrate our 100th mission. But honestly speaking I am beginning to get a little worried about ISRO.

Rahul M · Post by **Rahul M** » 09 Sep 2012 17:43

if we need a launch pad won't one in A&N island chains be a better option ?

congrats ISRO ! it's a sign of their consistency that we have become accustomed to their success with PSLV.

Asit P · Post by **Asit P** » 09 Sep 2012 18:08

Heartiest congratulations to ISRO for 100th successful space mission. The great Aryabhata might be smiling in heavens today.

abhijitm · Post by **abhijitm** » 09 Sep 2012 18:09

Rahul M wrote:if we need a launch pad won't one in A&N island chains be a better option ?

Being far away from the mainland managing logistics could be an issue. Also space centers observe frequent visits of various delegations, domestic and foreign, and A&N being a major military base it could be uncomfortable to accommodate research and military at one place.

JMT.

pgbhat · Post by **pgbhat** » 09 Sep 2012 18:25

The launch.

dinesha · Post by **dinesha** » 09 Sep 2012 19:39

PIB Photos
The Prime Minister, Dr. Manmohan Singh visiting the GSLV MK III vehicle assembly facility at Sriharikota on September 08, 2012.

High Res: Chart showing D3 FAC report and modifications

kit · Post by **kit** » 09 Sep 2012 19:41

ISRO is becoming very averse to risk taking ., the GSLV and manned space flight do have high elements of risk . Its the will of the people at the helm that decides the path of an organisation.I don't expect much from ISRO., if they can pull of the mars mission at least ., then good.

geeth · Post by **geeth** » 09 Sep 2012 19:47

When it comes to ego, Indian scientific community is worse than the Bureaucrats. Add to it that they have an elephant's memory when it come to taking revenge on someone (ofcourse junior and smarter!)

Why no one is asking them why the payload carrying capacity of Indian rockets have remained same over the past 20 years? Their modifications appears to me like the HM modifications to the good old Ambi..change the grill and mark it as Mark II..Add a leather cover to steering wheel and mark it as Mark III and so on.

akashganga · Post by **akashganga** » 09 Sep 2012 19:49

Congratulations ISRO for another successful launch. Eagerly waiting for the first GSLV with desi cryo success. ISRO should definitely launch Mars mission in 2013 and not postpone it as it has delayed so many missions in the past. ISRO now should act like Nasa boldly go and be prepared for failures, learn from failures and march forward. Bharat Mata Ki Jai.

SriKumar · Post by **SriKumar** » 09 Sep 2012 20:11

100th launch is major milestone. The PSLV is great program. Just checked out the wiki on this. Spot6 is the heaviest foreign satellite to date, and by far heavier at 720 kg than the 300 kg Israeli satellite. Also, the '99 C2 launch entry mentions tracking stations at B'lore, Lucknow, Mauritius, Bearslake (Russia; but I could not locate this place) and Biak (Indonesia). Am assuming that other stations have been added, especially on the other side of the earth. Unrelated observation: the rocket slowed down a bit during the 3rd stage when approaching 3rd stage separation.

SSridhar · Post by **SSridhar** » 09 Sep 2012 20:18

SriKumar wrote: Unrelated observation: the rocket slowed down a bit during the 3rd stage when approaching 3rd stage separation.

Normally, when one stage burns out and the next stage ignites, there is a small coasting phase.

Bade · Post by **Bade** » 09 Sep 2012 20:27

Congrats for 100th successful launch, but would have been nice if it was one of the Indian payloads waiting forever for a slot. ASRTOSAT where art thou ?

Singha · Post by **Singha** » 09 Sep 2012 20:35

our heavy launcher program has fallen into a rut for various reasons. next 2 yrs if we cannot proof the desi cryogenic engine on a couple of flights, things will get bad...there are no more rus cryogenic engines left anyway. we need to maintain a higher launch frequency also to improve comms , C3I , SAR , Sigint, IMINT ..... many of these even the PSLV can do, but our production and launch rate of PSLV again is quite low.

meantime Cheen is investing heavily in improving and adapting its successful long-march heavy launchers and looks on the verge of being able to attack Ariane on price front.

Varoon Shekhar · Post by **Varoon Shekhar** » 09 Sep 2012 20:43

geeth: not entirely accurate. The first successful PSLV launch in 1994 carried 804 kg. The next one about 920kg. There was a significant leap in PSLV C-1 with a 1203 kg payload. This was achieved partly by firing 4 of the 6 strap-ons first, as opposed to the earlier 2 followed by 4 air-lit. The next major enhancement came with the first Cartosat launch, which weighed well over 1500kg. RISAT-1 launched a few months ago was 1858 or about 300 kg heavier than the previous heaviest one.

If you think about it, every launch has its own individuality, and contains something or other different. It doesn't necessarily have to be payload capacity. It could even be something like a launch in heavy rain, as one back in 2003 achieved. Or it could be the number of satellites(5,7,10), the mix of Indian and non-Indian sats, the type of sats, or the mission itself, like Chandrayaan.

There is an aesthetic quality to every vehicle launch, no matter how frequent the event is. It is a sheer joy to see a large rocket like the PSLV lift off time and again.

But we would all love to see the GSLV Mark 2 and Mark 3 up and running

. May it happen in the next year.

SriKumar · Post by **SriKumar** » 09 Sep 2012 20:50

SSridhar wrote:
SriKumar wrote: Unrelated observation: the rocket slowed down a bit during the 3rd stage when approaching 3rd stage separation.
Normally, when one stage burns out and the next stage ignites, there is a small coasting phase.

Agreed. So what is intriguing is that this slowdown/coastaing phase exists only for the 3rd stage and not other stages. If you look at the velocity vs. time profile of the rocket at any time in the above video posted by pgbhat a few posts above; but let's pick timepoint 7:14 in the video, the only slowdown in the entire mission is during the 3rd stage. None of the earlier stages have a drop in the velocity profile. In addition, this 'coasting phase' lasts about 2 minutes. Watch the pgbhat video from 9:25 onwards...it shows the velocity profile again. PS3 separates around 9:41 and PS4 ignites around 9:52 (based on the vocal announcements which have a few seconds lag from the actual event). If we are to believe that PS3 shut down around 7:32 or later (per vocal announcement), PS3 is a dead weight and still going for the ride for a good 2 minutes before it separates. Very interesting.

geeth · Post by **geeth** » 09 Sep 2012 20:53

There is an aesthetic quality to every vehicle launch

That is exactly what I said.. change the grill and make it Mark II or III as you like it!

geeth · Post by **geeth** » 09 Sep 2012 20:56

So what is intriguing is that this slowdown/coastaing phase exists only for the 3rd stage and not other stages. I

During coasting, they use the gravity to increase velocity without burning rocket fuel. In turn, the rocket loses ome altitude...In other words, some of the potential energy is converted into kinetic energy. This way it is supposed to be more efficient, as there is loss due to drag in outer space.

symontk · Post by **symontk** » 09 Sep 2012 21:10

PSLV second stage has both ullage and retro rockets. So after PS1 cutoff, ullage rockets take the rocket forward before the PS2 ignition. After PS2 cutoff, retro rockets fire, and push back the PS2. However there are no ullage or retro rockets for PS3 or PS4. Thats why there is a coasting phase needed after PS3 cutoff

Instead of A&N or Srilanka, best place in India for polar rocket launch could be Kutch, Karwar, Kanyakumari or Balasore

SriKumar · Post by **SriKumar** » 09 Sep 2012 21:11

geeth wrote:
So what is intriguing is that this slowdown/coastaing phase exists only for the 3rd stage and not other stages. I
During coasting, they use the gravity to increase velocity without burning rocket fuel. In turn, the rocket loses ome altitude...In other words, some of the potential energy is converted into kinetic energy.

I guarantee you the altitude never reduces for this rocket. Even in this 'coasting' phase, it is still going upward. Check range vs. altitude at 6:00 (or any other time point where they show the range vs. altitude). It never reduces. One could argue that range vs. altitude is not the same as time vs. altitude but I am confident for this rocket launch that range is always increasing monotonically with time. I dont know whether the reduction in velocity (which is only in the first decimal point or so: e.g. 5.5 km/sec to 5.4 km/sec or something like that) is a deliberate maneuver to make the separation easier by reducing some load, or do they need the time to 'prepare' the 4th stage for separation, or is it a 'holding mode' of sorts to adjust the velocity parameters for injection into orbit after the final stage ignites.

member_23694 · Post by **member_23694** » 09 Sep 2012 21:13

i think we also need to consider the orbit of the launches conducted by PSLV (so probably a 3 tonne launch for LEO is also possible for PSLV) ...the issue is ISRO started with conservative payloads during the initial flight for PSLV and never exploited its full potential....until recently with around 1800KG payload.....
My perception is that ISRO got really aggressive with its launch vehicle capability under G Madhavan Nair.....but the current ISRO again seems to look like the 80s-90s period ....very conservative....and taking there own sweet time......
The scientist who led the Vikas engine team and later headed the Cryo engine team is out of ISRO.....the boss who bought aggression in rocket launch capability is also out of ISRO...... No proper GTO capable rocket..... No heavy lift capacity.... get a sad feeling especially in competition with China.....
At least after today;s launch there could have been some announcement for Mark 3 and GSLV with Indian Cryo launch schedule and there status..... but NO News.....

Rahul M · Post by **Rahul M** » 09 Sep 2012 21:15

abhijitm wrote:
Rahul M wrote:if we need a launch pad won't one in A&N island chains be a better option ?
Being far away from the mainland managing logistics could be an issue.

it won't be farther away than guyana or similar proposals here ! or even sri lanka, the logistics problem would involve either a ship based transport or at a stretch -- air based one. neither is undoable.

Also space centers observe frequent visits of various delegations, domestic and foreign, and A&N being a major military base it could be uncomfortable to accommodate research and military at one place.

errm, A&N is a fairly largish island chain and only a handful have any military presence (and those have a pretty high foreign tourist presence), the majority are uninhabited as well. this is not a problem.

symontk · Post by **symontk** » 09 Sep 2012 21:20

dhiraj wrote:i think we also need to consider the orbit of the launches conducted by PSLV (so probably a 3 tonne launch for LEO is also possible for PSLV) ...the issue is ISRO started with conservative payloads during the initial flight for PSLV and never exploited its full potential....until recently with around 1800KG payload.....
My perception is that ISRO got really aggressive with its launch vehicle capability under G Madhavan Nair.....but the current ISRO again seems to look like the 80s-90s period ....very conservative....and taking there own sweet time......
The scientist who led the Vikas engine team and later headed the Cryo engine team is out of ISRO.....the boss who bought aggression in rocket launch capability is also out of ISRO...... No proper GTO capable rocket..... No heavy lift capacity.... get a sad feeling especially in competition with China.....
At least after today;s launch there could have been some announcement for Mark 3 and GSLV with Indian Cryo launch schedule and there status..... but NO News.....

A rocket at max can carry a payload which is close to its dead weight of its 4th stage. Otherwise satellite and rocket will tumble before separation. So if PSLV has to carry 3 tonnes, the empty last stage should have close to that weight. One option is to remove the 3rd stage and quadraple the engines for 4th stage (a costly option). Other one being, remove the current 3rd and 4th stage and add the cryo stage for GSLV Mk2

My dream PSLV is - S200 from GSLVMk3 as first stage, L60with increased width to match S200 and C-20 / 25 with a payload capacity of 3-4 tonnes to GTO

SriKumar · Post by **SriKumar** » 09 Sep 2012 21:24

symontk wrote:PSLV second stage has both ullage and retro rockets. So after PS1 cutoff, ullage rockets take the rocket forward before the PS2 ignition. After PS2 cutoff, retro rockets fire, and push back the PS2. However there are no ullage or retro rockets for PS3 or PS4. Thats why there is a coasting phase needed after PS3 cutoff

Thanks. this explains the no slowdown from stage 1 to 2 (ullage) and stage 2 to 3 (retro). Am wondering why does it need 2 minutes to transition from stage 3 to 4. Stage 3 cuts off but does not separate for almost 2 minutes which seems like a very long time.

symontk · Post by **symontk** » 09 Sep 2012 21:29

SriKumar wrote:
symontk wrote:PSLV second stage has both ullage and retro rockets. So after PS1 cutoff, ullage rockets take the rocket forward before the PS2 ignition. After PS2 cutoff, retro rockets fire, and push back the PS2. However there are no ullage or retro rockets for PS3 or PS4. Thats why there is a coasting phase needed after PS3 cutoff
Thanks. this explains the no slowdown from stage 1 to 2 (ullage) and stage 2 to 3 (retro). Am wondering why does it need 2 minutes to transition from stage 3 to 4. Stage 3 cuts off but does not separate for almost 2 minutes which seems like a very long time.

Since PS2 has ullage rockets, the velocity of the rocket is not impacted and so the liquid fuel of the PS2 will be closer to the engine below. However there are no ullage rockets for PS4 and so the sudden decelration will put pressure on the upper chamber of liquid fuel containers. I am not aware of the exact dynamics to the time, maybe it requires 2 minutes to stabilize and bring the fuel pressure normal. Also remember its almost vaccum at that height

svinayak · Post by **svinayak** » 09 Sep 2012 21:39

Singha wrote:our heavy launcher program has fallen into a rut for various reasons. next 2 yrs if we cannot proof the desi cryogenic engine on a couple of flights, things will get bad...there are no more rus cryogenic engines left anyway. we need to maintain a higher launch frequency also to improve comms , C3I , SAR , Sigint, IMINT ..... many of these even the PSLV can do, but our production and launch rate of PSLV again is quite low.

meantime Cheen is investing heavily in improving and adapting its successful long-march heavy launchers and looks on the verge of being able to attack Ariane on price front.

There could be a secret technology restriction regime which we may not be aware.
There are several foriegn countries which want to make sure that India does not have the capability on cryo etc.

Several countries could be together colluding to make sure that India fails. ExtrAordinary efforts have been made by India's adversaries including money/resources to deny India and Indians access to many things.

Varoon Shekhar · Post by **Varoon Shekhar** » 09 Sep 2012 23:49

Acharya, it is simply astounding that the same commentators who are very critical of India's nuclear, missile and space programmes, are quite comfortable with, or at least accepting of, China's programmes. Leaving aside the 'racism and colonialism' angle, which does exist, what internal logic would cause them to be accepting of China's efforts, but not India's?

India of course, extends the comparison to France, the UK, Russia and the US. It doesn't see why those countries should be allowed to have strategic industries, but not India. But even with respect to the narrower India-China issue, there are people who barely mention China at all, or dismiss almost outright India's concerns vis-a-vis China. The Economist used phraseology like ( not exact quote) "India is using the excuse of China to maintain its own nuclear weapons capability". Similar wording can be found in commentaries by SIPRI, the miscalled "Stockholm International Peace Research Institute", and by several others.

Also interestingly, Pakistan is not pilloried directly for its own nuclear and missile programmes. It's almost taken as a given that Pakistan has a right to respond to India's missile and nuclear testing, and that Pakistan will give up its programmes if only India would do the same. Pakistan is not criticised per se. The same courtesy is not extended to India with respect to China, North Korea, Pakistan or anyone.

vasu raya · Post by **vasu raya** » 10 Sep 2012 00:02

Congragulations ISRO! looks like time has come to delegate PSLV to private sector to ramp up as they had announced recently

In the case of Sea launch, will say 6 strap-on rockets be enough to stabilize the main rocket from the platform's pitch and roll conditions, the concentric circle of thrust produced by them is modulated much like how Dhanush system stabilizes the ship launched Prithvi, if the feedback loop is in the order of milliseconds

Another one is with the recent A-5 (&A-4) tests, they got rid of the separator's and were using small retro rockets instead, why can't they make such an improvement in space launch vehicles as well?

SaiK · Post by **SaiK** » 10 Sep 2012 01:18

MMS should have given an OK for a moon lander rather.. we need that mission preceding mars mission. We should have own lander with a scanner, searcher and digger for H3.

TSJones · Post by **TSJones** » 10 Sep 2012 01:40

Congratulations to India on a job well done!

Singha · Post by **Singha** » 10 Sep 2012 07:57

There could be a secret technology restriction regime which we may not be aware.
There are several foriegn countries which want to make sure that India does not have the capability on cryo etc.

could be. but some of our own internal capacity and production rates does not look good. in a article in ajai shukla blog someone from a missile lab was saying the lead time for maraging steel cases is *one year* sourced from midhani. thats not good. there could be other long lead domestic items as well.

Varoon Shekhar · Post by **Varoon Shekhar** » 10 Sep 2012 08:06

And while we are all eagerly awaiting good news on the GSLV, let's applaud the PSLV launch for one more reason: the launching of the French satellite SPOT. All these years, India has made use of French launchers for its heavier satellites, and before the IRS sats went up, were dependent on SPOT and Landsat. Now history has come full circle in a way, with India lofting a French satellite for the first time. Not many countries can claim that. When are we going to see Brazil, South Korea, Israel or Iran launch a SPOT into orbit? Won't happen for a while!

member_23694 · Post by **member_23694** » 10 Sep 2012 08:11

There were some discussion about other potential launch sites etc......
currently ISRO has two launch pads....and assuming two VAB....
now how much time does a PSLV integration takes place...assuming 2 Month (max)....and say 6 month of the time when SHAR can be used for launch.....even then we can have 6 launches per year..... (please correct me if any of the assumption is wrong).....
but still we have less number of launches....so my understanding is we have to increase the rocket building capability and there capacity currently rather than thinking about multiple launch sites.....
It seems more a case of misplaced priorities....like the Mars mission....

Lilo · Post by **Lilo** » 10 Sep 2012 08:52

vina wrote: Ideally once we get the GSLV MKIII and IV versions in, we should get in touch with the Brazilians / Ariane and build a launch pad for these vehicles ,also PSLV in Brazil's Alicantra space center or in Korou. That will allow us to haul a couple of hundred kgs more to orbit as they are bang on the equator. The Russians for eg, have built a brand new Soyuz launch facility in Korou, French Guyana. If ESA /Ariane wont play ball, Brazilians would be more than happy I think . Time to ask them to put money where the mouth is and ask them to back up that South-South co-operation rhetoric with substance.

The (ex)British Guiana (the current "Guyana" contiguous to the other Guiana's) has a majority population of PIOs

The largest ethnic group is that of the descendants of indentured labourers from India also known as East Indians (Indo-Guyanese), comprising 43.5% of the population in 2002.

It would make a nice location to establish an ISRO launch center near equator.

Singha · Post by **Singha** » 10 Sep 2012 09:07

would southern Sri lanka also work? this might have better strategic and logistic benefits. for instance, using a dedicated airstrip, people could fly from places like trivandrum or bangalore in a couple hours on ATR72/EMB145 type shuttle flights as needed.

TSJones · Post by **TSJones** » 10 Sep 2012 12:12

I'm not sure what you guys are expecting to benefit for having a launch site near the equator? For instance, the US has the cape in florida. It's OK but it is still a long ways from the equator. We're happy with it. Suits us fine. Our other major base is just north of Los Angelos at Vandenberg AFB. We use it for polar orbits. Fine and dandy right?

We'll not exactly. Our partners for the ISS, Russia, has to launch northeast over Siberia due to its neighbor China which is due east of Kazakistan. That means any launches that the US wants to do to the ISS must launch from the cape directly northeast along the US Atlantic sea coast in order to track the russian orbit inclination. Sucks, huh?

Well not that much really. It's been calcualted the shuttle only lost 7% payload capacity for havng to launch northeast from the cape. Not that much is it?

So again I must ask, what benefits exactly do you expect for launching near the equator?

member_23694 · Post by **member_23694** » 10 Sep 2012 13:09

TSJones wrote:I'm not sure what you guys are expecting to benefit for having a launch site near the equator? For instance, the US has the cape in florida. It's OK but it is still a long ways from the equator. We're happy with it. Suits us fine. Our other major base is just north of Los Angelos at Vandenberg AFB. We use it for polar orbits. Fine and dandy right?

We'll not exactly. Our partners for the ISS, Russia, has to launch northeast over Siberia due to its neighbor China which is due east of Kazakistan. That means any launches that the US wants to do to the ISS must launch from the cape directly northeast along the US Atlantic sea coast in order to track the russian orbit inclination. Sucks, huh?

Well not that much really. It's been calcualted the shuttle only lost 7% payload capacity for havng to launch northeast from the cape. Not that much is it?

So again I must ask, what benefits exactly do you expect for launching near the equator?

I completely agree..... make a 4-6 tonne GTO capable launcher and i am fine with the loss of 100-200 Kg due to launch site issue