Indian Space Program Discussion

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ashokpachori
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Re: Indian Space Program Discussion

Post by ashokpachori »

I will not disagree with you

Not me but a newbie who got subdued by you without rhyme or a reason.

Woo him!

Elya su karo cho bapu....
disha
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Re: Indian Space Program Discussion

Post by disha »

Matt Stone wrote:
And some articles to prove that we still dont have PROVEN cryogenic upper stage engine
http://www.ndtv.com/news/world/gslv-fai ... -20108.php
Matt, you are not helping your cause by quoting Undy-TV. Also, almost all of the Indian media when it comes to scientific/millitary reporting comes into DDM category.
I may be a new member but just criticizing me for the opinion's and facts (which are true) is not fair i think. I clearly see a sense of arrogance and bulliness in your replies to me.
Welcome aboard. Please strive not to make generalizations based on few DDM data points.
And you comparing the cost to scam ; i am not taking about money here - I am talking about the time that is taken to design a proven indigenous GSLV
It takes time. Like currently US manned-spaceflight is "dead". It is relying on Russian launches and it will be almost a decade before it will restart again (assuming it does). Yes, this things take time even in US and hence it is costly! And hence not more than 5 nations (Russia, US, India, China, Japan) have mastered launching rockets (ESA does not count as a nation, it is an agency).

So my condolences to you too on the failure of GSLV. Just wishing the best to ISRO to complete their analysis and come back to launch pad.
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Re: Indian Space Program Discussion

Post by Shankar »

it was a first stage control failure - some control chords snapped - why still to be determined - so when the rocket went of predicted course self destruct command was issued by safety officer and the rocket exploded - the orange fumes are N2O4 unburnt getting released
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Re: Indian Space Program Discussion

Post by juvva »

Shankar wrote:it was a first stage control failure - some control chords snapped - why still to be determined - so when the rocket went of predicted course self destruct command was issued by safety officer and the rocket exploded - the orange fumes are N2O4 unburnt getting released
just guessing wildly: could the control cables have snapped because of cryogenic fluids spilling on them - the earlier launch delay was attributed to a leaky (LOX?) valve in the cryogenic stage.
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Re: Indian Space Program Discussion

Post by Virupaksha »

[quote="ashokpachori"][/quote]
ashok,

before you burn yourselves, it is clear that you have no knowledge about isro, step back and learn instead of using rhetoric.

Dog-leg is the maneuvre which every Indian rocket has to perform so that its debris even in case of accident does not fall on Indonesia and sri lanka.

http://www.hinduonnet.com/fline/fl1612/16120370.htm

Failures because we are still learning and not sitting idle. Before ariane came into being, there was europa - which had total of 5 launches, all unsuccessfull and 1 launch cancelled even before it was launched.
http://en.wikipedia.org/wiki/Europa_rocket

Ariane 1 had 2 failures in first 5 launches after europa. araine2 's first launche was a failure. ariane 3(basically ariane 2) had a flop. By ariane 4, the tech stabilized and had more than hundred successes and only 3 failures. Even ariane 5's first 2 were unsuccessful and then 5 th or so was again unsucessfull.

Pakistan has no failures because it does not do rockets.

At the end of the day, it IS rocket science.
ashokpachori
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Re: Indian Space Program Discussion

Post by ashokpachori »

Austin wrote:Are these Sattelite and SLV insured so that atleast the financial loss is absorbed ?

Austin which risk are you talking about? is it a pre ejection or a post ejection of the satellite?

If the payload is lost during the voyage (pre ejection) is one aspect, and other being its workable space life. Premium works out to about 20% owing to risky nature of its premature failure.

New India Assurance takes care of this business.
ashokpachori
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Re: Indian Space Program Discussion

Post by ashokpachori »

ravi_ku wrote:
ashokpachori wrote:
ashok,

before you burn yourselves, it is clear that you have no knowledge about isro, step back and learn instead of using rhetoric.

Dog-leg is the maneuvre which every Indian rocket has to perform so that its debris even in case of accident does not fall on Indonesia and sri lanka.

http://www.hinduonnet.com/fline/fl1612/16120370.htm

Failures because we are still learning and not sitting idle. Before ariane came into being, there was europa - which had total of 5 launches, all unsuccessfull and 1 launch cancelled even before it was launched.
http://en.wikipedia.org/wiki/Europa_rocket

Ariane 1 had 2 failures in first 5 launches after europa. araine2 's first launche was a failure. ariane 3(basically ariane 2) had a flop. By ariane 4, the tech stabilized and had more than hundred successes and only 3 failures. Even ariane 5's first 2 were unsuccessful and then 5 th or so was again unsucessfull.

Pakistan has no failures because it does not do rockets.

At the end of the day, it IS rocket science.
Lets see who ends up in crematorium!
Before anything, please tell me how is it (dogleg) responsible for component failure as I said?

The last component failure (turbo pump) was due to dogleg?
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Re: Indian Space Program Discussion

Post by krisna »

Saw and heard the sad news of the GSAT 5P launch.
Failures are nothing but a stepping stone to future success.
ISRO has to continue to learn and work on the experience gained.
ISRO requires more encouragement from common Indians particularly in these trying times so that they conquer greater frontiers in space technology.
ashokpachori
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Re: Indian Space Program Discussion

Post by ashokpachori »

In three days, ISRO will come out with how and why this happened, Radhakrishnan said. There was a valve leak problem in the cryogenic stage that was noted last Sunday, which was then rectified.

Making it clear that the valve leak and its subsequent rectification had nothing to do with Saturday’s downturn, Radhakrishnan parried a query on whether any “sabotage” could have triggered the disaster.

“I don't know about that,” he quipped
.
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Re: Indian Space Program Discussion

Post by vera_k »

Is there any particular reason why ISRO has to persist with the troubled Mk2 design when the GSLV Mk3 launcher is almost ready? Why not cut losses and abandon the Mk2 program entirely?
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Re: Indian Space Program Discussion

Post by disha »

ashokpachori wrote: Lets see who ends up in crematorium!
Before anything, please tell me how is it (dogleg) responsible for component failure as I said?

The last component failure (turbo pump) was due to dogleg?
Bad taste. Ravi_ku was very nice and patient with you.

He explained lucidly the failures on Arianne when you compared Arianne with ISRO and how many "less" failures it had.

Now regarding "dog leg" maneovre, it puts unnecessary strain on the rocket and complicates the control software. It also has impact on the consumption of fuel and hence impact on payload. In some cases, the dog leg maneovre changes the direction of the rocket by as much as 90 degrees. None of Arianne has to do that.

From the article on PSLV quoted by Ravi_ku:
In view of the south-eastwardly launch instead of an ideal due south launch, which is decided on to avoid flight over Sri Lanka, PSLV has a complex pitch/yaw control system to carry out the complicated dog-leg manoeuvre after it passes over Sri Lanka and continues due south. This in effect entails a loss of payload capability by at least half a tonne, according to ISRO scientists. In the absence of another launch site, this cannot be avoided. It is for this reason that at one point of time, Balasore was explored as a suitable launch site. However, the idea was abandoned owing to other logistical considerations.
So comparing apples to oranges and doing a whole scale Rona-Dhona will lead you nowhere. Reading up first will help a lot.

Anyway, it does appear to be a freak failure where the chords were severed. This could not be designed and tested on table top.

PS: Edited to quote the article.
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Re: Indian Space Program Discussion

Post by Shankk »

Kanson wrote:It is the time they need our support.
Thank you for mentioning this. It is important to realize the difference between erstwhile ISRO and today's organization. Capabilities and aptitude of individuals is one thing that plays pivotal role in successful operations but there is another factor involved too. The best period for ISRO that was extremely successful also coincides with the period when ISRO was a very low profile organization. Others either laughed or ignored poor and destitute India venturing into space. ISRO was pretty much left alone to do whatever they wanted. Then came a time when ISRO was getting too successful and started stepping onto toes. This is also the time ISRO started having blemishes on their record.

I am not claiming any espionage attempt in this incidence as I don't have any proof. What I am saying is that as a Joe six pack or a chilli chicken when I read BR or other sources and witness all the cheers, analysis and future predictions it makes me wonder what if these sources are right? Do I want that? Is that a problem for me? Can I do something about it?

Besides it is quite debatable whether all this analysis is really useful for India as VERY VERY less percentage of this analysis is actually put into practice to change ground realities. BR is very successful in letting the whole world know how Indians think, what kind of actions they can possibly take or what options they have WITHOUT benefiting much from all that analysis.
ashokpachori
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Re: Indian Space Program Discussion

Post by ashokpachori »

Bad taste. Ravi_ku was very nice and patient with you.

Was he with the following gems:

before you burn yourselves

And your simple and generic two liner theory borrowed from Ravi´s article does not do you any justice as to any co-relation of dogleg - a out of plane maneuver with lattitude and longtitude control - with cause of malfunctions. The flip side of the dogleg is undesirable extra fuel, which in turn means lesser payload.

We have had lesser payload in the past (with dogleg that is) yet with succesful mission!
Why then, and not now?

And you say dogleg is a common denominator?

You failed to prove the corelation of dogleg with turbopump and recent chord snaping....

My gally!

Please come back and tell every BRite how many accidents have been caused by so called dogleg.

Till then, sleep well and Merry Christmas.
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Re: Indian Space Program Discussion

Post by ashokpachori »

In some cases, the dog leg maneovre changes the direction of the rocket by as much as 90 degrees.

And what are those cases, that are responsible for 90 degree turn? can you please educate me with latitude and logtitude inputs?

Launch vehicles are programmed bodies designed to do thier job flawlessly as much as possible. If the program/command wants it to, it will take desired/programmed orbital inclination - but not on its own, which may mean that rocket has veered off - mission aborted.
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Re: Indian Space Program Discussion

Post by vasu_ray »

In these days of high speed wireless datalinks, can they not have a backup of wireless communication between the mission computer and other control sub systems?
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Re: Indian Space Program Discussion

Post by SaiK »

There is nothing like overconfidence in science and engineering. If it is a test rocket, it -is a- test rocket/period.

also, there is something call CMM.
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Re: Indian Space Program Discussion

Post by disha »

ashokpachori wrote:And what are those cases, that are responsible for 90 degree turn? can you please educate me with latitude and logtitude inputs?
Can you do a little bit of google and find it out yourselves please?
Launch vehicles are programmed bodies designed to do thier job flawlessly as much as possible. If the program/command wants it to, it will take desired/programmed orbital inclination - but not on its own, which may mean that rocket has veered off - mission aborted.
Again over-generalizations. Can you please design a two-stage rocket (even if it is a model) and send it at least a km high and recover it safely? After that add in complexities like sending a workable payload (for eg. camera will do) or take air/atmospheric data. Then scale it up with cluster engines and then cluster engines with two stage rockets. Note this should be your own design and not some off-the shelf models. Then do a comparitive analysis between your designs and off the shelf models (you can also fly them) and in the analysis do note the design challenges you faced and how you overcome them. Yes it is lot of hardwork and it will take years. And it is a learning process. Unless you have been through that you will not know.

BTW, the current failure with dog leg is your association - not mine. My point is simple, you cannot generalize Arianne with GSLV. Even though they look similiar (GSLV MkIII and Arianne V). There is more in the brains that meet the eye.

Till then enjoy your holidays and sleep well.
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Re: Indian Space Program Discussion

Post by Anoop. A. »

There was a change in the design of the GSLV F06 resulting in overall structural changes, like more fuel in CUS, increased diameter of the payload fairing, increase in weight from 414 to 418 tonnes and increase in the length of the vehicle from 49 to 51 meters. These Variables does change the behaviour of the rocket aerodynamically, so Isro has to re design/update the guidance software for proper functioning. Then we are talking about a new rocket (not the vanilla GSLV, where there were changes but not as significant as the ones here). I hope Isro has done Wind tunnel tests on the new design before putting on the launch pad.

ARIANE 5 had a disastrous start for ESA, considering the performance of ther then work horse ARIANE 4, it was unbeliveable.Now, ARIANE 5 is one of the most reliable medium lift launcher in the world today. So, there is nothing to be deperessed about, because ISRO had a similar run with the ASLV program before and i'm sure they will bounce back...
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Re: Indian Space Program Discussion

Post by disha »

vasu_ray wrote:In these days of high speed wireless datalinks, can they not have a backup of wireless communication between the mission computer and other control sub systems?
Please do not feel offended: Is it a question or an opinion? If it is an opinion - can some research go before expressing it? We have some people on board talking about how unlucky is Sri Radhakrishnan. Others are comparing it with Arianne and telling how much better they are with so few failures etc.

In case it is a set of questions, another set of questions to ponder about: What is the speed of the rocket? How fast will it go up in air? Which wireless technology you propose (3g/4g mobile wireless? Infrared? Radio? Ultrasonic? Microwave?). How will it work in say @10km up in the atmosphere?
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Re: Indian Space Program Discussion

Post by vasu_ray »

^^^
its a question of feasibility because anything critical usually has a backup, radio waves suitable for close range communication unlike telemetry, so high bandwidth mobile communication should be good enough but any spectrum reserved for space communication should be ok
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Re: Indian Space Program Discussion

Post by ashokpachori »

There is nothing like overconfidence in science and engineering. If it is a test rocket, it -is a- test rocket/period.


Overconfidence is when you take a gamble, just as in ISRO´s case, by not using dummy satellite, assuming everything would go well.

It was a matter of judgement (taken by ISRO boss), what CMM has to do in this situation.

Same thing applies when ISRO did (sometimes) get insurance on its payload, and did not on other time, taking risk that is.....
Last edited by ashokpachori on 26 Dec 2010 03:35, edited 1 time in total.
ashokpachori
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Re: Indian Space Program Discussion

Post by ashokpachori »

Can you do a little bit of google and find it out yourselves please?

The onus remains on you because the 90 degree polemic was started by you.

BTW, the current failure with dog leg is your association - not mine

Above is a lie and the proof is in the (following quote) pudding:
Hint: There is a reason for that, for eg. something to do with Dog legs. Posted: 25 Dec 2010 23:27

Following is a horse manure sans any direct relivance to dogleg:
Can you please design a two-stage rocket (even if it is a model) and send it at least a km high and recover it safely? After that add in complexities like sending a workable payload (for eg. camera will do) or take air/atmospheric data. Then scale it up with cluster engines and then cluster engines with two stage rockets. Note this should be your own design and not some off-the shelf models. Then do a comparitive analysis between your designs and off the shelf models (you can also fly them) and in the analysis do note the design challenges you faced and how you overcome them. Yes it is lot of hardwork and it will take years. And it is a learning process. Unless you have been through that you will not know.
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Re: Indian Space Program Discussion

Post by ashokpachori »

Anoop. A. wrote: increase in weight from 414 to 418 tonnes and increase in the length of the vehicle from 49 to 51 meters. These Variables does change the behaviour of the rocket aerodynamically, .

SLV was 22 meter with just 40 kg payload limit. Success, Developmental Flight April 1983

ASLV with 24 meters and payload limit 150 Kg. May 1994 success.

PSLV with 44 meters with GTO payload limit 1060 Kg. Successful 15 times.

And GSLV even bigger, so what is the grouse here? When PSLV got matured from ASLV and became successful despite bigger payload and taller configuration......
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Re: Indian Space Program Discussion

Post by disha »

The onus remains on you because the 90 degree polemic was started by you.

http://www.aprsaf.org/data/aprsaf14_dat ... nary1c.pdf
Hint: There is a reason for that, for eg. something to do with Dog legs. Posted: 25 Dec 2010 23:27
That is to be associated with complexities in launching from Sriharikota compared to launching from Kourou. It was not my intention to associate it with the current failure which seems to be pretty localized. The point again is simple, the trajectories from SHAR are complex and should not be trivially compared to Arianne. Or for that matter with any other trajectories or why so and so has "less" failures than us injuns.

Following is a horse manure sans any direct relivance to dogleg:

No that is leg-work meant for enterprising people to undertake. At least the hope is it will prevent people from making half-a$$ed opinions.
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Re: Indian Space Program Discussion

Post by disha »

ashokpachori wrote:And GSLV even bigger, so what is the grouse here? When PSLV got matured from ASLV and became successful despite bigger payload and taller configuration......
:rotfl: Guess it was due to Dr. Kasturirangan's good luck.
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Re: Indian Space Program Discussion

Post by Virupaksha »

Ashok,

Apart from accusations and insinuations, in your posts in this thread, I did not find anything else (except 1 insurance post) to add ot the knowledge of this thread. You dont need to accuse ISRO's chairman personally of over confidence when a rocket fails.

Do you know the cost of designing, making the dummy & making sure it doesnt end up of space debris vs the cost of making a copy of an already designed satellite? If this flight would have succeeding, what is the price of making the whole rocket anew? I dont have the data, but before you accuse ISRO of overconfidence, I would like to see the data you have to accuse.

Regarding the cost of 150 crore which you saw as cost of satellite, it includes the cost of designing the satellite as well and generally it is the higher part of cost. If not, I would definitely like to see the data by which you contradict and accuse ISRO's chairman.

It was talked as of a test launch, so everyone including the satellite owner knew the risks.

FYI,

SLV had 2 failures out of 4 launches.
ASLV had 3 failures out of 4 launches.
PSLV's first and 4th launches were failures.

So if you will excuse me, the only time ISRO had continuous successes were with the PSLV's , i.e. 90's and early 2000's. Even today they have it, they are moving on to the next level, so failures are to be expected. I expect that this GSLV tech will stabilize in the next 3-5 years, then 10 years of continuous success and then another phase of rhona dhona and the accusations will start again.
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Re: Indian Space Program Discussion

Post by Virupaksha »

disha wrote:
ashokpachori wrote:And GSLV even bigger, so what is the grouse here? When PSLV got matured from ASLV and became successful despite bigger payload and taller configuration......
:rotfl: Guess it was due to Dr. Kasturirangan's good luck.
even PSLV's first launch was a flop :((

So Dr. Kasturirangan was bad luck too :P
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Re: Indian Space Program Discussion

Post by ashokpachori »

disha wrote:
ashokpachori wrote:And GSLV even bigger, so what is the grouse here? When PSLV got matured from ASLV and became successful despite bigger payload and taller configuration......
:rotfl: Guess it was due to Dr. Kasturirangan's good luck.
And here is your own quote:
We have some people on board talking about how unlucky is Sri Radhakrishnan.

I refuse to engage with a person like you who resorts to lying

Hint: There is a reason for that, for eg. something to do with Dog legs. Posted: 25 Dec 2010 23:27
Live with it.
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Re: Indian Space Program Discussion

Post by ashokpachori »

Apart from accusations and insinuations, in your posts in this thread, I did not find anything else (except 1 insurance post) to add ot the knowledge of this thread.

Here is how you started in the following:

before you burn yourselves
Pot calling kettle black?

You dont need to accuse ISRO's chairman personally of over confidence when a rocket fails

I did not accuse anyone, marely commented (without exhortaions) on his probably implied judgement to not use dummy satellite, two satellites gone in a row, hence I have some reason. Besides, several other countries like France-USA-China-North Korea have used dummy sats, so why India is singular in this case?

Do you know the cost of designing, making the dummy & making sure it doesnt end up of space debris vs the cost of making a copy of an already designed satellite?

I dont know the actual cost - do you?

Regarding the cost of 150 crore which you saw as cost of satellite, it includes the cost of designing the satellite as well and generally it is the higher part of cost. If not, I would definitely like to see the data by which you contradict and accuse ISRO's chairman.

Everyone would agree that a dummy satellite would cost much less and nobody needs to utilise any rocket science in this.
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Re: Indian Space Program Discussion

Post by Vivek K »

All ISRO owes itself is to dissect the failure clinically, blame whatever needs blame, rectify the problem and have a successful launch! Go ISRO!
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Re: Indian Space Program Discussion

Post by nirav »

ashokpachori wrote:
ISRO overconfidence!
The overconfidence effect is a well-established bias in which someone's subjective confidence in their judgments is reliably greater than their objective accuracy, especially when confidence is relatively high

I think you have made your "overconfident" Arm-Chair Jarnail Assessment of ISROs confidence levels very well.

Request you to NOT derail this otherwise very informative thread with more tripe.
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Re: Indian Space Program Discussion

Post by akashganga »

Good try ISRO. All space nations have had failures. Many americans, and russians have died in space mishaps but they persisted and continue on. I am sure ISRO/GSLV will mature and become a workhorse like PSLV. Try, try, and try again until u succeed. cheers.
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Re: Indian Space Program Discussion

Post by ashokpachori »

nirav wrote:
ISRO overconfidence!
The overconfidence effect is a well-established bias in which someone's subjective confidence in their judgments is reliably greater than their objective accuracy, especially when confidence is relatively high


Request you to NOT derail this otherwise very informative thread with more tripe.

You should have thought of the (following) tripe first before you indulged me:
before you burn yourselves
I would be glad if I found you to be an equal oppurtunity employer.
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Re: Indian Space Program Discussion

Post by Virupaksha »

ashok,

"burn yourselves" is a very common english idiom
http://idioms.thefreedictionary.com/burn+fingers
The museum has gotten burned on several paintings purchased recently that have turned out to be fakes.
So calm down, it doesnt have the connotation of burning you alive or crematoriams or anything like that.
Its other meaning is "over work yourselves"/dont get hyper.
http://www.goenglish.com/Idioms/Burning ... lf+Out.asp
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Re: Indian Space Program Discussion

Post by Mort Walker »

Do we know if the control signal was an electrical one or mechanical control that failed?

If it is electrical, then the possibility of an enemy (or supposedly friendly country) could have used a powerful enough RF pulse aimed at the GSLV shortly after launch. A powerful well focused pulse can penetrate the skin of a rocket, and thereby create a voltage on an electrical control line causing interference. As modern electronics are now below 5v levels, shielding becomes an issue and you can do it, but there is a trade-off with increased weight. Powerful ship based EW anti-missile systems do exist and are operational.
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Re: Indian Space Program Discussion

Post by SSridhar »

Guys, there is no need to engage in violent discussion. I am issuing appropriate warnings to those who have indulged in that in the last few pages.
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Re: Indian Space Program Discussion

Post by vasu_ray »

Submarine based auv popping like a periscope can train a ew pulse as well, naval ships are too obvious
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Re: Indian Space Program Discussion

Post by arun »

Mr D. Sasi Kumar, former head of ISRO Liquid Propulsion Systems Centre quoted in the Deccan Chronicle on the likely cause of the GSLV FO6 launch failure:

“This is the most stupid thing to have happened to a space mission of this magnitude. From the TV visuals, I got a feeling that the strap-on rockets of the first stage got detached within seconds of lift-off,”

From here:

Isro blames side rockets; ‘carelessness’ in the air
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Re: Indian Space Program Discussion

Post by symontk »

Dog legs can be avoided by using the Chandipur / Balasore facility in Orissa. But the facility set up costs will be there.

ISRO should continue working on GSLV-2 since that only can provide the necessary inputs for GSLV-3 which means that until GSLV-2 is sucessful there wont be any GSLV-3.

For the INSAT programme, its better to take PSLV / KALPANA route until we perfect GSLV. Its not cost effective but in the interiem its unavoidable. Another solution is to have a cryo stage on top of PSLV instead of its 3rd and 4th stages. This would be a cost effective solution for most part. A launch vehicle with S200 + L55 + C15 should do the trick, it should be able to launch a GSO payload of 1800-2000kg, which is a decent payload.

Regarding the failure, its tragic that quadrapled chords (1 main 3 backups) failed simultaneously. (But I am not still clear that this failure occured first or something else occured which caused this. You can't have all the chords cut at the same time).
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Re: Indian Space Program Discussion

Post by ramana »

Hindu's TSS reports
GSLV flights jinxed?

Its silly to write like this. GSLV is complex system and its failure mode will be a normal accident as described by Prof Charles Perrow. So through root cause analysis has to be done. ISRO has doen that in the past and will do so now. No need of jinx an buri nazar type stories.
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