LCA news and discussion

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enqyoob
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Re: LCA news and discussion

Post by enqyoob »

Oh, thank you, I didn't know all that... thanks for the deeply thoughtful analysis.
Gagan
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Re: LCA news and discussion

Post by Gagan »

Abhiti,
The ISRO guys get paid at government rates don't they? The do launch satellites and send moon missions don't they?

There's your answer.
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Re: LCA news and discussion

Post by NRao »

Funding is an issue when related to R&D, not so much to pay packs. Although better pay will make some difference, it is not what motives everyone out there.

Even if the GoI were to provide good pays, still it will be a few years before a good product will come out. In between there is bound to be a few engines that burn up, fail on the ground, fail in the sky, etc, etc, etc.

GoI has to take some risks too.

It is a very risk proposition - a lot of funds need to be supplied.

lastly, India needs mature reporters - crucial.
ChandraS

Re: LCA news and discussion

Post by ChandraS »

abhiti wrote:
narayanan wrote:Why the Handicrafts industry is not developing gas turbine engines - there is a GTRE that pretends to be doing this. So WHY is it not right to ask why GTRE has been such an abysmal failure for all these decades?

I note that Maruti Suzuki and Mahindra build cars/ SUVs that compete fairly well against Honda and Chevrolet in the Indian market, hey? They seem to be moving along a lot quicker than Hindustan Motors was doing with the Ambassador. Why is GTRE then still trying to impress us by failing to develop a 1975 jet engine in 2009? Why should Indians not demand some answers for this? Why is the response to such questions no brighter than this guilt-complex thing as in your post?

Indian Babus cannot be allowed to hide behind this Patriotism cra* when all they are doing is ripping off the nation and blocking key executive positions with their musharrafs. Those who know the problems, should feel emboldened to speak out.
GTRE can build some engine with some thrust. But asking it to compete with the likes of GE or Snecma or Honeywell doesn't seem fair. It is like asking why Infosys despite decades of experience in IT not able to compete with Cisco in networking or Oracle in DB or Intel in microprocessor or Apple/Microsoft in Operating Systems. If it were so easy to replicate cutting edge technology why will folks buy engine from GE, some Chinese company will already be building it cheaper. Also I wouldn't depend on govt department to develop cutting edge technology. If you want cutting edge you need to pay engineers the market rate...cannot do that in govt.
Abhiti,

Thanks for the very insightful response. The brilliance of argument shines right through. That's why Reliance should be given responsibility for anything that needs to get done! :D
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Re: LCA news and discussion

Post by KrishG »

There we go again! The GTRE bashing has started! :| :|

I have suggestion. Can everybody of you give your opinion on where GTRE or GOI goes from here. That will be a more productive discussion. Let's hear everybody's opinion on the restructuring required in our R&D (especially gas turbine research).
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Re: LCA news and discussion

Post by abhiti »

Gagan wrote:Abhiti,
The ISRO guys get paid at government rates don't they? The do launch satellites and send moon missions don't they?There's your answer.
No ISRO doesn't face the same dynamics as GTRE. Unlike GTRE, ISRO doesn't need to match LM + NASA to last 10% of performance. But matching the last 10-15% is paramount for a fighter engine. And when I talk about salary it is not that you can one day raise the pay of all the engineers at GTRE and suddenly you will have a better engine. Higher salary is about hiring and retaining best talent. When Russians and Chinese try to match Americans in engine technology using govt employees they depend on a lot of espionage which GOI is not going to do.
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Re: LCA news and discussion

Post by Misraji »

Dear god!!!

Why does every new kid on the block feel the need to point out "What he thinks" should be done to improve GTRE, DRDO and research in general in India ... :evil:

Let them do their jobs ... The most constructive thing you could do is do yours....

This thing about public sector, private sector, reliance, yada yada is getting really monotous ....

In fact, a humble suggestion to the mods:
Could the newbies (including me of course) be restricted to the Newbies thread for (say) the
first hundred posts ...

It would really reduce the signal-2-noise ratio and do the forum quality a world of good.

Regards,
Ashish.

PS: Err ... Make that 500 posts ... Nobody in this thread seems to have post count below 100 ... :oops:
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Re: LCA news and discussion

Post by Cain Marko »

Misraji wrote:PS: Err ... Make that 500 posts ... Nobody in this thread seems to have post count below 100 ... :oops:
Ayyo! I yam glad you are not a moderator wonlee! Still, newbie status should not depend on post count at all imho but on year of join up. There are some guys (oldies) there who can contribute meaningfully but have paltry post counts. The software upgrade reduced most people (all but the very, very oldies) to flimisy post counts.
JMT

CM.
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Re: LCA news and discussion

Post by sombhat »

Misraji wrote: Why does every new kid on the block feel the need to point out "What he thinks" should be done to improve GTRE, DRDO and research in general in India ... :evil:
Dude, why have a forum at all. Just watch aastha channel. One guy speaks, others nod. :lol:
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Re: LCA news and discussion

Post by dipak »

ChandraS wrote:
abhiti wrote: GTRE can build some engine with some thrust. But asking it to compete with the likes of GE or Snecma or Honeywell doesn't seem fair. It is like asking why Infosys despite decades of experience in IT not able to compete with Cisco in networking or Oracle in DB or Intel in microprocessor or Apple/Microsoft in Operating Systems. If it were so easy to replicate cutting edge technology why will folks buy engine from GE, some Chinese company will already be building it cheaper. Also I wouldn't depend on govt department to develop cutting edge technology. If you want cutting edge you need to pay engineers the market rate...cannot do that in govt.
Abhiti,

Thanks for the very insightful response. The brilliance of argument shines right through. That's why Reliance should be given responsibility for anything that needs to get done! :D
And make IN, BARC handover everything at SBC to L&T.
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Re: LCA news and discussion

Post by anirban_aim »

sombhat wrote:
Misraji wrote: Why does every new kid on the block feel the need to point out "What he thinks" should be done to improve GTRE, DRDO and research in general in India ... :evil:
Dude, why have a forum at all. Just watch aastha channel. One guy speaks, others nod. :lol:
:rotfl: :rotfl: :rotfl: :rotfl: :rotfl: :rotfl: :rotfl: :rotfl: :rotfl:
ChandraS

Re: LCA news and discussion

Post by ChandraS »

dipak wrote:
And make IN, BARC handover everything at SBC to L&T.
Sigh.. no one gets sarcasm these days :roll:

Many moons ago (actually way too many moons ago..) similar discussions would end up with one side asking all the govt sector projects to be handed over to the private sector with Reliance oft being quoted as the epitome of efficiency, result oriented performance meeting or exceeding the targets, ityaadi.. :|
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Re: LCA news and discussion

Post by SaiK »

just got off talking to an ex-isro guy, who went, had he been in isro now, he would be somewhere getting at 70kpm. imho, a pretty decent amount per ISI stampings.

and good enough, for asking the right question to the right person if placed at the right position.
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Re: LCA news and discussion

Post by KrishG »

SaiK wrote:just got off talking to an ex-isro guy, who went, had he been in isro now, he would be somewhere getting at 70kpm. imho, a pretty decent amount per ISI stampings.

and good enough, for asking the right question to the right person if placed at the right position.
ISRO does have a good payscale by Indian standards. 18k at the beginning to 70k-80k for scientists.
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Re: LCA news and discussion

Post by Rishirishi »

KrishG wrote:
SaiK wrote:just got off talking to an ex-isro guy, who went, had he been in isro now, he would be somewhere getting at 70kpm. imho, a pretty decent amount per ISI stampings.

and good enough, for asking the right question to the right person if placed at the right position.
ISRO does have a good payscale by Indian standards. 18k at the beginning to 70k-80k for scientists.
Tell me which IIT fresher would not be discoraged by the payscale. For 18K you will get a fresher who does not manage to make it into the call centre industry :shock: .

At 70-80K with 15+ experiance you will get people who are not employable anywhere else.

A lot of dudes end up working for ISRO, because of the thrill and worksatisfaction. Unfair for a person who may posess worldclass brains.
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Re: LCA news and discussion

Post by Shameek »

Rishirishi wrote:Tell me which IIT fresher would not be discoraged by the payscale. For 18K you will get a fresher who does not manage to make it into the call centre industry .
A lot of IT firms still pay 18k as a starting salary. And what people do there is many a times an insult to their brains. Its just more glamorous to say you work in software I guess. And it is not just IIT people who are smart are they?

This is going big time OT.
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Re: LCA news and discussion

Post by babbupandey »

Just to make a point, my starting salary right after MBA was Rs 19,984/- (I still remember this because it fell short of 20k mark), Rs 18,000 looks better in that respect. Don't forget that sarkari jobs are not known for their pay-packet but the perks they offer. People live in plush houses (worth 10-15k per month in rent), get their own cars (when you move up), travel, newspaper and so many other things. Plus (and a big plus), you get a better work-life balance.
Private = 10L per year of salary (average) + 20L worth of headache (at the minimum) :twisted:
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Re: LCA news and discussion

Post by Rishirishi »

babbupandey wrote:Just to make a point, my starting salary right after MBA was Rs 19,984/- (I still remember this because it fell short of 20k mark), Rs 18,000 looks better in that respect. Don't forget that sarkari jobs are not known for their pay-packet but the perks they offer. People live in plush houses (worth 10-15k per month in rent), get their own cars (when you move up), travel, newspaper and so many other things. Plus (and a big plus), you get a better work-life balance.
Private = 10L per year of salary (average) + 20L worth of headache (at the minimum) :twisted:
You want the best of the best for your premier reserch companies. Indias capability is mesured by what ISRO can achieve and the security may depend on it.

You certainly do not want the type that are seeking a "work-life" balance at the begining of their worklife. India ends up paying huge ammounts to foregin companies for second grade tech. Why not start to pay top salary and attract the best of the best.

I am sure that a starting salary of 50K reaching 2-3L after 10 years would attract the best. There is a saying. If you pay peanuts you get monkeys. I am not saying that ISRO people are bandars.
A lot of the top people are today the winners of 60's and 70's because they did not have a chance to get job elsewhere. Jus
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Re: LCA news and discussion

Post by enqyoob »

abhiti opines:
No ISRO doesn't face the same dynamics as GTRE. Unlike GTRE, ISRO doesn't need to match LM + NASA to last 10% of performance. But matching the last 10-15% is paramount for a fighter engine.
Let's see:

1. The commercial satellite launch market is one of the most cut-throat of all markets. Please GOOGLE "FUTRON" for reports on what has happened there. ISRO has to succeed in getting orders for commercial satellite launches there, and then fight all the govt. sanctions etc. etc. to get these payloads approved.

2. Also, I wonder if you have tried doing the calculations to see what will happen if a given launcher's engines perform only to 85% of the performance of competing engines. Let's see: Ariane 3rd stages these days claim 450 seconds vacuum Isp. So if ISRO has only 387 seconds Isp on their 3rd stages, is that enough? What will this do to the mass ratio of Indian rockets?

3. DOES GTRE come close to matching "last 10%" of LM+NASA? If they did, no one here would have anything but praise for them. Compare the thrust-to-weight ratio of GTRE's still-2-b-demonstrated Kaveri engine of the year 2012, with that of modern fighter engines, which were built say 5 years ago. IS GTRE within 10% of the best? 15%? 25%, 50%?????????

4. Check the the impact on payload fraction, range, turn radius, and climb rate of an aircraft equipped with Kaveri Engine (when it is demonstrated successfully) vs., say, a Russian engine from an Su-27 (which is probably 20 years old technology now).

5. Check what terms such as "bypass ratio", "turbine inlet temperature", "overall pressure ratio", "stage pressure ratio", and "polytropic efficiency" mean and compare the values of the GTRE engine with those of modern engines.

Then you may see why people here have lost patience with the total cra* that GTRE has been trying to sell to the VERY SYMPATHETIC AND PATIENT Indian public with their periodic rah-rah "news releases" - continuing an unbroken pattern of the last 40+ years.

Very seriously, per the specs released for what the Kaveri is even TRYING to achieve, the IAF would do better to go to the junk auctions in Russia (where u can buy a MiG-31 airframe for $5), or to the desert junkyards in the US, and buy some 1970s engines that have been ITAR-cleared because their technology is so old, and put those on the LCA production line. They will beat the Kaveri (to be demonstrated in 2012?) by a long way.

As for how to reorganize the Indian aircraft engine R&D&M program,
1. Change the name of GTRE to "GTAO" (for "Gas Turbine Acoustics Office", because their top officials sure do :(( :(( like jet engines). Ask them to turn over their records of experience in trying to get things built in India, and any solutions that they would have liked to implement.
Hire away the few people at GTRE who are not "404" (I don't mean the GE engine number) and still have some "fire in the belly".
2. Set up an office empowered to recruit teams consisting of university researchers, engineers and production experts from the engine factories, automobile assembly line quality control experts, IAF pilots, materials experts, and others, under one absolute SOB who understands the issues and has a record of getting results.

The other establishments that are needed will be set up by said SOB. A couple of variable-pressure test cells will have to be built. Some decent instrumentation will be required. Several grants and contracts to universities are needed. A couple of large grants to Indian manufacturers of turbines etc. will be needed, to create competition.
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Re: LCA news and discussion

Post by prabhug »

Hai
I am ready to work for indian defense research who is going to hire me ?? :!: I mean nobody is welcome expect you are a NRI .

Cheers

Prabhu.G
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Re: LCA news and discussion

Post by krishnan »

So you mean to say that all the people working in indian defense research are NRIs
Last edited by krishnan on 18 Aug 2009 11:38, edited 1 time in total.
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Re: LCA news and discussion

Post by prabhug »

I mean the one really interested is given less opportunity.Only when u prove yourselves somewhere else you are welcome. OK. My question is like this If somebody wants to work with defense research , what can he do to get into it(Is there any process with these institutions to do so?).If you don't attract the most interested how are going to deliver? If IIT's can only deliver why promote engineering in all other colleges.Hope some of the missile man's are not from IITs.I felt it's not the compensation but the lack of proactive approach the organizations lack.The lack of professionalism with the academic research centres.

My argument is when the defense development is privatized the most change is not going to be in the management but the people who work . Though the people in private companies will have less degree of freedom they are going to innovate more since private companies are going to hire the best motivated people.

Cheers

Prabhu.G
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Re: LCA news and discussion

Post by PratikDas »

prabhug wrote:My question is like this If somebody wants to work with defense research , what can he do to get into it(Is there any process with these institutions to do so?).
DRDO: Recruitment and Assessment Centre
ISRO: Job Opportunities
NAL: Training Opportunities

Best of luck!
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Re: LCA news and discussion

Post by govardhanks »

prabhug wrote: My argument is when the defense development is privatized the most change is not going to be in the management but the people who work . Though the people in private companies will have less degree of freedom they are going to innovate more since private companies are going to hire the best motivated people.

Cheers

Prabhu.G
There are advantages and disadvantages from both sides. So when both are together they will work well. my opinion :)
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Re: LCA news and discussion

Post by harbans »

Sorry for the OT, but was responding to the pay scale ISRO topic..ISRO makes a profit. For every dollar it spends it earns another. Wy not give hem stock options say after a period of working? Let that option be applicable in all public sector firms but on the condition that they are not union affiliated. So those who want to remain in unions don't benefit from stock options in the long run and will want to lose affiliation to take advantage, while working to keep the PSU profitable? Slowly the PSUs can get more profitable as the demand from it's workers tends to hive off shares to expand stock options available to employees, whilst at the same time moving away from backward nion affiliation and increasing profitability in the concern and still retaining the PSU label..just thinking aloud, and apologies for the OT.
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Re: LCA news and discussion

Post by k prasad »

For ESOs, ISRO must be a public company... not a bad idea, but needs discussion.

Coming to govt jobs... at the moment, govt jobs are extremely cushy and challenging, especially at an entry level. The pay, esp after 6pc isn't bad at all.

The best part is that these jobs (I'm talking abt DRDO, ISRO and CSIR) give ppl the skills that industry jumps at. I mean, its rare to find a guy with 3 years experience who has expertise with Adaptive Signal Processing - you'll only find someone from DRDO ISRO or AEC who fits the bill. And cos are willing to pay gold for such guys.

Thats the trend right now - a lot of scientists with 5-10 yrs experience are leaving and joining industry for 10x the salary. Its not a bad trend, as long as there are good people left at the helm of things. With industry also getting involved in defence & govt projects, its good to have these people working there.

The skills gained at DRDO and elsewhere means that there is a huge demand for these jobs. Its not as bad now as it was 5 years ago. The freeing up of Pvt defence has really helped. However, the 5-10 experience is the concern, since this is when most scientists start giving back to the organization (0-3 years is learning phase, 3-6 is participation and 6+ is leadership)
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Re: LCA news and discussion

Post by Cain Marko »

Gurus,
I have wonlee one question - with all this MRCA testing hoopla going on, what happens to YELSEEYA testing? I hope none of that team was disturbed?

CM>
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Re: LCA news and discussion

Post by krishnan »

Most probably was, thats why the testing is going slow
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Re: LCA news and discussion

Post by sohamn »

The LCA is progress is going so slow that everybody in this thread is discussing everything else apart from LCA. :D
I am desperate to see LSP-3,LSP-4 information. So, I open this thread everyday expecting to see info about them, instead I see info about GTRE, MRCA, Politics, MBA, peoples salary, ISRO etc etc.
This shows the progress LCA has made in the last one year. :cry:
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Re: LCA news and discussion

Post by krishnan »

It has made better progress in the last one year. You can expect the LSP-3 or 4 to be in air by next month as per someone from orkut LCA group
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Re: LCA news and discussion

Post by PratikDas »

krishnan wrote:It has made better progress in the last one year. You can expect the LSP-3 or 4 to be in air by next month as per someone from orkut LCA group
I hope you are right. I could always put in one more cent/paisa into the piggy bank of broken promises.
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Re: LCA news and discussion

Post by abhiti »

I don't want to now bring down ISRO to save GTRE but some dose of reality check wouldn't hurt.
narayanan wrote:1. The commercial satellite launch market is one of the most cut-throat of all markets. Please GOOGLE "FUTRON" for reports on what has happened there. ISRO has to succeed in getting orders for commercial satellite launches there, and then fight all the govt. sanctions etc. etc. to get these payloads approved.
Sar it is cut throat in terms of cost per pound. We Indians are the masters of cost.
2. Also, I wonder if you have tried doing the calculations to see what will happen if a given launcher's engines perform only to 85% of the performance of competing engines. Let's see: Ariane 3rd stages these days claim 450 seconds vacuum Isp. So if ISRO has only 387 seconds Isp on their 3rd stages, is that enough? What will this do to the mass ratio of Indian rockets?
Sar, American space shuttle has been making rounds since 1981. NASA has been exploring Mars, Jupiter, Neptune, Uranus. NASA has been leaders in astro physics. How are we doing in this regard?
3. DOES GTRE come close to matching "last 10%" of LM+NASA? If they did, no one here would have anything but praise for them. Compare the thrust-to-weight ratio of GTRE's still-2-b-demonstrated Kaveri engine of the year 2012, with that of modern fighter engines, which were built say 5 years ago. IS GTRE within 10% of the best? 15%? 25%, 50%?????????
Sar here is the comparision:

Engine (thrust-length-inlet diameter-weight)
Kaveri 73KN-3490mm-910mm-1100kg
F414 98KN-3912mm-889mm-1060kg
RD33 81KN-4250mm-1040mm-1055kg

SO it may be 25% not 15%.But Russian engines wouldn't cut it. Russians match by building everything bigger to compensate. We are Indians, when we design LCA we assume we will match GE performance.
5. Check what terms such as "bypass ratio", "turbine inlet temperature", "overall pressure ratio", "stage pressure ratio", and "polytropic efficiency" mean and compare the values of the GTRE engine with those of modern engines.
Saar it has been a while I read about engines and that also was to pass exam. So you need to help me with these.
Last edited by abhiti on 19 Aug 2009 18:11, edited 2 times in total.
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Re: LCA news and discussion

Post by Rahul M »

Kaveri 65KN-3490mm-910mm-1100kg
what exactly is this ?
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Re: LCA news and discussion

Post by abhiti »

Rahul M wrote:
Kaveri 65KN-3490mm-910mm-1100kg
what exactly is this ?
This is what I remember from some old reports about Kabini producing enough dry thrust i.e. 51KN but far below on wet thrust. I see one news item which claims it having reached 90% of target which is 80KN. But with LCA has additional weight of 1.5 ton so 80KN is not going to cut it. Therefore engine specs have been revised to 95KN requirement.
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Re: LCA news and discussion

Post by Rahul M »

I know what kaveri design specifications are.

you have posted AB thrusts of the other two engines. 65 kN is still less than 90% of 81 kN, which is ~ 73 kN. please correct the post.
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Re: LCA news and discussion

Post by enqyoob »

Thanks. Now let us compare the results:

Kaveri 65KN-3490mm-910mm-1100kg
F414 98KN-3912mm-889mm-1060kg
RD33 81KN-4250mm-1040mm-1055kg

The RD33 is too big, evidently, (though only by 13 centimeters of diameter) but it is still lighter than the Kaveri, which says a lot about the technology.

So thrust-to-weight ratio comparisons (actually all of them must be wet-thrust values, no one gets T/W of 8 or 9 with dry thrust without Djinn Magic Carpets):
Kaveri: 65000/(1100*9.8 ) = 6
F414: 98000/(1060*9.8 ) = 9.43
RD33: 81000/(1055*9.8 ) = 7.8

So Kaveri engine reaches 6/7.8 = 77% of the Russian RD-33 and 6/9.43 = 63.6% of the American F414.

Now if you compare thrust-specific fuel consumption, you will see the effect of GTRE's 1970s technology on the range and payload of the LCA, vs. modern engines.

(OT, but just to illustrate what it takes for ISRO to survive in the world of commercial satellites)

If this were ISRO, instead of 450 seconds Isp, the Indian GSLV would have engines producing 288 seconds Isp.

LEO (equatorial) to GEO delta-v is approx. 3,900 m/s per what they taught me in the Binori madarssa.

Mass Ratio of a rocket from LEO (equatorial) to GEO with Isp 450 seconds is 2.42. With Isp 288 seconds it would be 3.98.

So, bottom line is that you can put nearly twice as much mass in GEO with the 450 second engine than with the 288 second engine.

No amount of desi cost-cutting is going to make THAT competitive. And anyway, if Indian PSUs were "masters of cost", Air India would be the most profitable airline in the duniya, hain? The buggers don't even deliver delayed luggage to passengers' homes! So maybe one solution would be to merge GTRE and Air India?
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Re: LCA news and discussion

Post by Rahul M »

Kaveri: 65000/(1100*9.8 ) = 6
F414: 98000/(1060*9.8 ) = 9.43
RD33: 81000/(1055*9.8 ) = 7.8
just a nitpick, that would be around 6.8 instead of 6.
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Re: LCA news and discussion

Post by KrishG »

If this were ISRO, instead of 450 seconds Isp, the Indian GSLV would have engines producing 288 seconds Isp.
Let's make one thing clear. Specific Impulse is not dependent on the engine design. It depends on the propellant and the external pressure.

Well, as I know of it most of ISRO's engines' TWR is lower than that of other engines rated at similar thrust. ISRO is also trying to increase the Engine mass ratio of all it's engines with the help of composites etc. There is no major issue here. It's a learning process! It's happening slowly but surely.

I got the Stage Mass-Ratio of C-25 verified from my friend and he said that with a 5 ton empty weight of C-25, GSLV Mk-III could hardly put 3.5 tons to LEO. I am not sure about the 5 ton empty weight figure, it was posted here on BR by somebody.
Rahul M
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Re: LCA news and discussion

Post by Rahul M »


Rahul, in the Binori it was haraam to learn how to use decimals. :oops: OK, so the Kaveri is considerably better than my calculations showed, but still lags modern designs by a very long way. Though I can't do elementary arithmetic,
:lol:
actually you used the wrong figure, abhiti has since corrected it. (65 --> 73)
KrishG
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Re: LCA news and discussion

Post by KrishG »

And when you go from the LEO madarssa to the GEO madarssa, the "external pressure" is....? :roll: I guess it depends on whether it is raining or clear sky?
Specific impulse varies with altitude. It's maximum value is in vacuum.

http://en.wikipedia.org/wiki/Specific_i ... al_engines

Specific Impulse is directly proportional to the effective exhaust velocity which in turn is proportional to the Thrust. Pressure is force per unit area, which does affect the exhaust gases.
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