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gslv markIII

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Yeah that’s what I am saying - we are stuck with an unpopular Russian technology. So now what? Can we develop an oxidizer SC tech or the latest full cycle tech?
Can we bring the Mk3 launch costs 30% cheaper than Falcon9?

Why is ISRO not openly discussing any of this, btw?
1. SCE 200 is based on ORSC.

2. There is little need for any new upper stage engine now- CE 20 is enough. Payload improvement by stage inert mass optimization by using lighter structures/ tankages (CFRP/Al-Li alloy), development of restart capability etc would be more cost effective than any new higher Isp engine.

3. SpaceX Falcon use GG cycle merlin engines.

4. Would need Semi cryogenic engines as well as higher production rates. It's a WIP.
 

Mantospace

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we are spending more than 1.5 lac crores and 2.5 lac crores on minority and SC/ST schemes, while ISRO and DRDO budgets are less than 15K crores each
Really feel sometime why i giving tax. These useless scheme consuming all money.

20k crore to drdo and isro not big money. But govt dont want to give.

Better ISRO concentrate on making current things better. Dont concentrate on market. Be it with science and india need. If govt not gvng fnd wat ISRO can do.
 

RoaringTigerHiddenDragon

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1. SCE 200 is based on ORSC.

2. There is little need for any new upper stage engine now- CE 20 is enough. Payload improvement by stage inert mass optimization by using lighter structures/ tankages (CFRP/Al-Li alloy), development of restart capacity etc would be more cost effective than any new higher Isp engine.

3. SpaceX Falcon use GG cycle merlin engines.

4. Would need Semi cryogenic engines as well as higher production rates. It's a WIP.
Am talking about CE7.5. Why are we using this unpopular technology when we know others are not using it? Maybe this tech has a high rate of failure. But ISRO got stuck with it. I guess we shall wait for the relaunch and see what happens.
But GoI not giving ISRO the required budget is a big red flag.
 

Mantospace

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Am talking about CE7.5. Why are we using this unpopular technology when we know others are not using it? Maybe this tech has a high rate of failure. But ISRO got stuck with it. I guess we shall wait for the relaunch and see what happens.
But GoI not giving ISRO the required budget is a big red flag.
Hw can we expect from isro if govt not giving budget.

I thnk sometimes isro take those steps due to budget issue.
 

gslv markIII

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Am talking about CE7.5. Why are we using this unpopular technology when we know others are not using it? Maybe this tech has a high rate of failure. But ISRO got stuck with it. I guess we shall wait for the relaunch and see what happens.
But GoI not giving ISRO the required budget is a big red flag.
1. All stage combustion cycle based cryogenic engines are fuel rich combustion cycles. Not ORSC. More advantageous to power the turbopumps by running a fuel rich preburner.

2. There is hardly any need for improvement- it provides the necessary Isp. That's what matters. Don't forget that even the SSME was a FRSC cryogenic engine.

3. It's known that the engine works both on the test stand and in flight. A QA issue once in a while isn't enough of a reason to junk it.

4. And there is simply no need to spend a few hundred crores a new CUS for gslv mk2. It fills a niche, doesn't have much growth left in terms of payload capabilities.
 

Akula

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The government has actually cut pay to 90% of ISRO scientists and engineers, in reality. Looks like the government knows the usual PSU corruption is going on in ISRO as well.


look at the pay scale. you are going to get monkeys for this pittance when private startups are zooming ahead.

Note in the tweet 289 ISRO scientists have left in the last 5 years obviously due to morale loss. I just laugh at a MOD here who thinks all is well at ISRO. Lol.
Skyroot aerospace co-founders are ex Isro employees.
 

pipebomb

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Never ever use complex technology if simpler ones are available. This is perhaps why other agencies don’t use staged combustion cycle. Russia does not use KVD 1 (from which CE7.5 is derived) anymore. Plus CE7.5 is NOT the latest tech. That would be Full flow staged combustion that SpaceX’s Raptor deployed in 2019. CE7.5 is a fuel rich staged combustion and looks like no other agency uses this technology anymore. Perhaps the failure rate is high due to complexity and hence have not gone that route.
Oxidizer rich staged combustion is the most popular. The technology ISRO uses was developed in the 1970s and not used anymore and even to begin with only 3 or 4 engines used it compared to more than two dozen engines using oxidizer rich staged combustion cycle. Looks like ISRO may have gone for a complex technology because only Russia was ready to tech transfer cryogenic technology I.e. KVD1 fuel rich SC cycle. So ISRO may not have had any choice. But they could have tried to develop the safer oxidizer rich SC or full flow SC tech all these year
To my knowledge there are no oxidizer rich hydrolox engine in the world. I heard somewhere that temp generated in oxidizer rich hydrolox engine are unmanageable, I don't know if its true or not.
 

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1. All stage combustion cycle based cryogenic engines are fuel rich combustion cycles. Not ORSC. More advantageous to power the turbopumps by running a fuel rich preburner.

2. There is hardly any need for improvement- it provides the necessary Isp. That's what matters. Don't forget that even the SSME was a FRSC cryogenic engine.

3. It's known that the engine works both on the test stand and in flight. A QA issue once in a while isn't enough of a reason to junk it.

4. And there is simply no need to spend a few hundred crores a new CUS for gslv mk2. It fills a niche, doesn't have much growth left in terms of payload capabilities.
ce7.5 lacks restart capability which can be useful for some innovative orbital mechanics or if you have to launch two satellites in different orbits. Weight factor in expander cycle engines becomes prominent when used in higher thrust class unlike upper stage engines.

Also it would easier/faster to reach reliability targets in expander cycle engine for isro compared to staged combustion. Staged combustion is more suitable for ground lit stage.
 

Mantospace

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Remember during cy2 launch time some leak found and engnrs rectify within 24 hours. So this should not take time for next gslv launch.

Something compromised during assembly or quality check.
 

Mantospace

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If we need to go next level, govt need to secure supply chain.

Clearly rus,chn and amrica dont want us in space. How US allko china to grow.
 

RoaringTigerHiddenDragon

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Hope private org can do something.
Hope private org can do something.
Yup…the usual PSU screwed up, let’s see if the private sector can help. At least the private sector will be a lot more proactive in communicating with space enthusiasts and at least trying to own up failures and explain what steps they are taking. With ISRO, everything is in the dark and we are told to believe everything they do is high and mighty and not questionable, despite the poor launch calendar performance over the last several years. ISRO can always clarify that this is all we can do with the budget we have. This is our new launch schedule etc. because of this failure. But they get all defensive and just hide and cry. And try to hide information. Nad several members here attributing god-like stature to ISRO is simply disgusting. No one , not even ISRO itself, benefits from such behavior.
 
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Mantospace

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Yup…the usual PSU screwed up, let’s see if the private sector can help. At least the private sector will be a lot more proactive in communicating with space enthusiasts and at least trying to own up failures and explain what steps they are taking. With ISRO, everything is in the dark and we are told to believe everything they do is high and mighty and not questionable, despite the poor launch calendar performance over the last several years. ISRO can always clarify that this is all we can do with the budget we have. This is our new launch schedule etc. because of this failure. But they get all defensive and just hide and cry. And try to hide information. Nad several members here attributing god-like stature to ISRO is simply disgusting. No one , not even ISRO itself, benefits from such behavior.
Budget issue creating problem for ISRO.
 

gslv markIII

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Staged combustion is more suitable for ground lit stage.
Agreed.

ce7.5 lacks restart capability which can be useful for some innovative orbital mechanics or if you have to launch two satellites in different orbits.
Yes, the same is the case with CE-20. Need some work wrt to electric igniters & stage modifications. Looks like ISRO is pursuing that for CE-20 alone. (source: VSSC director's presentations)

Weight factor in expander cycle engines becomes prominent when used in higher thrust class unlike upper stage engines.
Nice comparison, from conceptual studies for CE-20 I suppose.

LVM3-GGvsSC.png


You're right about the reliability, but is there a need for pursuing another engine for gslv mk2? Given, the weight increase of comm sats (Even I-8K being developed now, GSLV Mk2 would have limited opportunity apart from IGNSS sats or an odd GISAT).

The original plan was to upgrade gslv mk2's GTO payload to 3 tonnes, looks like they aren't pursuing it anymore.
 

fire starter

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ce7.5 lacks restart capability which can be useful for some innovative orbital mechanics or if you have to launch two satellites in different orbits. Weight factor in expander cycle engines becomes prominent when used in higher thrust class unlike upper stage engines.

Also it would easier/faster to reach reliability targets in expander cycle engine for isro compared to staged combustion. Staged combustion is more suitable for ground lit stage.
CE 7.5 is having restart capability it has not been demonstrated yet.
 

Indx TechStyle

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I hear you but it is you have made outrageous claims like “overseas Indians are dumb…”.
No, it's common sense. Anyone who's clueless about a field is dumb regarding that field. It's government of the nation which is the real hand behind such things.

Your argument is strictly Indians are dumb and western people or Indians working under western are somewhat superior (as if Dutch, Aussies and Brits are launching space stations or landing humans on moon). You killed argument when I said "Indians overseas are so low in such business and at first place don't wish to come to India."

So no, I was not even remotely offensive, you were.
Your dismissal of foreign talent does not augur well. We have had foreign coaches for almost all of our Olympic athletes as Indian coaches are not exposed to highly competitive areas.
No, it's about experience. Just as India needed initial foreign help to start technologies, India has not invested in Olympic sports to develop skills. So, it took foreign strategies of seed.

There is a reason why American cricket team is pathetic. They simply didn't work on it. Same stories goes with Indian companies having foreign staff. They need experience of others.

Space sector is strategic and technology available to steal in public domain is too low as compared to ISRO's level.
Your qualifications are not suitable for rocketry decisions either.
I have told earlier, I'm an engineer but not a scientist. I'm enough competent with material science and welding technology that I can fabricate anything if you give me drwaings. Be it a sugar plant or rocket nozzle. This is not R&D and just engineering and you will reach at same level in 10-12 years if you work in heavy industries. I have worked on proton gantries and nuclear reactors too.

Mistakes happen in workshops at this level and you are not willing to listen it. Enginners and not scientists fabricate things.

If rocket succeeded many times and failed once, it's the fault of enginners, not scientist. And when there are thousands of parts, failures once in many times happen.

Studying aerospace is my hobby not my profession.
And since you haven't even studied that but just giving plain opinions, you should not be considered.
I have an engineering background too, btw.
Doesn't matter. You aren't willing talk on technical aspects either.

You just made claims first and ignored the responses you got. There is an old joke Before thinking out of the box, there must be something inside the box. You can't offer solutions on anything if you don't even hold any basic knowledge of concept.

You don't have to be an ISRO insider to comment on aerospace. You can read on internet about why CE-7.5 is a big deal.
Also, you are attributing things to me that I never said - like replace Indian talent. I only said ISRO’s top leadership should gracefully resign from their leadership jobs as you don’t have to be rocket scientists to be in leadership jobs.
Both are completely nonsensical and can only be said by a 10-13 years revolutionary of school speeches. Leadership wasn't a part of problem at all. Sivan brought some of fastest accelerations to ISRO's programmes.

If you think otherwise, delightfully prove me wrong with how replacing a leadership will solve problem. As for "replacing talent", it was clearly so as far as I can read. You can explained that too.
I am all about adding more overseas Indian talent talent that has deep exposure to aerospace.
It's again strictly your belief. That's why I'm saying you never worked. Technology is not a single formula or blue print which anyone can just steal and become a superpower.

Can you provide any stats for Indians in western aerospace sector that they have deeper presence than others?

ISRO is one of 6-7 major space agencies and there are barely any companies it would need to spy on for technology. A Raj Kumar with a new aerospace start up in India or a western country has little to even advice ISRO. Bigger agencies are also strategic asset of their nation, employ their own people at most.

And let's imagine even if someone manages to bring classified SLS details from NASA to ISRO, what can ISRO do? Do you have any idea how long does it take to install fabrication, cranes and testing capacities. Or how difficult it is to guess material, it's heat treatment and welding technology.

Your approach is too simplistic, assumption based and desperate. World doesn't run on assumptions that west might be better racially to Africans might be uncivilised. It's for people without knowledge and understanding. All countries where they are today have worked their @$$e$ with failures to reach there.

Like a kid

Not worthy of responses anymore.
The amount of crap that ISRO and its scientists have got today from this forum is crazy. I understand the disappointment but if the only way you guys can let loose your frustration is by abusing the folks at ISRO, maybe you should stay off the forum and drown your sorrows elsewhere. ISRO more than does its share with what resources they have, they have had more success than not in all these years. It's a terrible indictment of all of us if instead of being supportive at the time of setbacks, we pile on the abuses. The good folks at ISRO don't deserve that.
 

Indx TechStyle

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we would all love that...BUT reality is, was and will be miles away from it...and the new Space Race is only to get more and more heated...ISRO's future looks between Scotland and Bangladesh (in cricketing terms) only

2018
View attachment 104498

2019
View attachment 104499

2020
View attachment 104500

2021 till now
View attachment 104501
No, that's total launch frequency which is very much proportional to aerospace production of these countries. In China's case, a lot included small and micro launchers.

US, Russia and China are first tier space powers and India, Japan and EU remain in second.

ISRO's expansion plan for 12-24 launches/year was to be executed in 2020-22 with new factories and vehicle assembly buildings (VAB) until COVID screwed it and half of budget went back to government unspent.
 

Indx TechStyle

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For the previous topic, it was just 2-3 launches/year in India every decade.
Looking at increasing satellite launches to 12-18 per year

After inducting SVAB, it became possible for ISRO to undertake 10+ launches an year. So they kept target 15-20 launches every year but delays happened everytime in industries limiting them to 7-8 launches. Now, COVID might have shut down many private workshops permanently which were working for ISRO.
 

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