Indian Space Program: News & Discussion - Sept 2016

[prasannasimha]

^ As far as costing is concerned this is not an accounting fudging but based on what ISRO is charging at present for commercial launches which are not subsidized but are for profit.

[prasannasimha]

^ the shock wave sources on rocket launch are multiple and not just the nose cone slicing through the atmosphere.

[nirav]

Punching out numbers on a spreadsheet is not research work.Its just a tabulated form of "I think, I feel" blah blah,4-6 tons to GTO ..

The making of rocket parts requires intense research. It's multi-disciplinary and lies at the boundary of current human knowledge. However, once the parts have been manufactured and their attributes accurately known, predicting the flight path is actually simple math which can be done using log tables and an envelop, forget a modern spreadsheet.

If one goes through our discussion, one would realize that Vina and I are actually opposed to each other. He was quite convinced that ISRO could have done better and I was sure the ISRO did the very best with what they had. Unfortunately, I don't know enough physics or math to say why. In the process of trying to prove what he contends Vina mathematically came up with a rudimentary model. According to his model, it was easier to understand quantitatively, why ISRO was doing what. But, the model is still not accurate. The model considers the thrust each stage as constant, This is true only for the second stage. The thrust of the first stage increases as the rocket travels from sea level to outside the atmosphere. The third stages thrust is regulated by ISRO for best results.

The depth of enthusiasm for different people is different. Some limit it to just congratulating ISRO's on successes. Others want to go deeper, and that does not constitute questioning ISRO's wisdom. I ask anybody on this forum to answer the following question, why is the 440,000 kg GSLV only able to launch 2.5 Tons to GTO, where others do much better? Can anybody reply? Some of us are trying to understand why. And those who can't answer are asking why are you investigating? I ask these so-called fans of Indian space missions: If I went up to Dr. Kalam (or any senior scientist at ISRO) and asked the same question, what would be their reaction. Would they encourage this discussion or berate this effort to understand?

BR used to be full of Arun_Ss, n^3s , Harrys etc. who used to only discuss technical points. Today's posters have thousands of posts to their credit, and can't answer simple questions. Yet they pontificate on what others should discuss, and even how this forum should be moderated. It is a real pity.

Indranil,

Im not sure if you have real all my posts regarding the topic on the GSLV and its configuration.

Thing is, i havent opposed dicsussing configurations in principle.I have strongly opposed the language and manner in which it is done.

Consider this, me talking down the infamous spreadsheet got someones echandee so violated he started his name calling spree on a different topic.Fact is, the person obviously cannot have a rational discussion without name calling when faced with a view which does not conform with his own.

If mockery of the spreadsheet and his efforts to "fix" GSLV,as ridiculous as it sounds, get him riled up so much, what do you think he has been doing wrt to ISRO all this while ? Its been going on for years.

If he thinks he has a free hand in talking crap about ISRO and its design choices and others should not mind, why should he then mind if his half a$$ed 30 minute spreadsheet efforts are given a similar treatment ?

ISRO has put in decades of work into getting where they are. If ISRO is fair game for name calling and making disparaging remarks then so is the 30 minute djinn spreadsheet.

Its amusing, between all the bellicose thundering and bumbling, credentials have still not been provided by Scientist S who has solved for ISRO to send 4-6 tons to GTO on GSLV MK2 based on a 30 minute spreadsheet.

[nirav]

[/b]Now what do the other honorable members have to say when presented direct scientific peer reviewed data ?
Isn't this type of discussion more cogent ?

Is it ? But why are YOU corrected? . I DIDN'T read the article, I just saw your quote from it, and I immediately knew they were wrong and didn't even have to open it. Are what the writers of the article, presenting "scientific peer reviewed data" or are they using data to shoot their mouth off on things they have no idea about .

Now, the "Sonic BOOM , YouTube" video poster will jump up and say , "How Arrogant" . He does not even open the article and disses the whole thing ! And another round of expletives and this and that!

To which I will respond, dude, at 20 odds seconds and until 45 odd seconds, when you claim that you started recording a "Sonic Boom" the Vehicle is NOT supersonic. If it is not supersonic, there can no shock wave (no Prandtl Meyer expansion), and since no shock wave, no sonic boom .

Then the "Sonic Boom YouTube" dude will furiously write back and say, how do I know that the vehicle is not supersonic ? Did an article from ISRO say that it is so ? Is there some thing that you Googled out that said it so ? To which I will respond, The Mach number / speed of sound at low altitudes is around 1300 km/h and the vehicle definitely is not that fast!

Immediately, "Sonic Boom" dude will try to pull out "data" to "prove" that the vehicle is indeed that fast. I will pull out the PSLV C11 brochure and say that at 20s, the vehicle's speed 625m/s, but for the purpose you are talking about you should subtract 425m/s , so in effect that is really 200 m/s ! He wont understand why 425m/s needs to be subtracted, hewill go into a spin again on this and that, until finally common sense will prevail .

Then the question is "are the esteemed authors of the report and their equally esteemed peer reviewers" wrong ? Are the seismometers wrong? Absolutely not. The data is right. They did measure an over pressure event and sonic waves. But where they shot their mouth off on calling it a "Sonic Boom" , which by what is commonly accepted in science is not. Now "Sonic Boom YouTube" dude will jump up and say, in our "universe", this is what I call a sonic boom. I would say, good, you can stay in your parallel universe.

Then "Sonic Boom YouTube" dude will get very clever and say, ah, but the launch video I posted was of GSLV MKIII, how do you know that I didn't record a sonic boom for that ? To which I will point back to my original post. Then he will post this PSLV/Chandrayaan article again, and it is a rinse and repeat.

I short , like I said, this thread is a "Space Nukkad" . We have people presenting some random long range launch videos with a bunch of near Yahoos, swearing in the choicest expletives and the garbage is presented as a "Sonic Boom" and THAT should be what "Indian Space" is about.

Moral : Do trust your judgement and common sense. Just because someone claims something, they could be plainly wrong, even if coming from people, with formal qualifications and even if published in a "peer reviewed journal".

A research report has been presented to you, yet your inability to get your head out of your arrogant musharraf is what you are putting on display for everyone to see.

"I did not see the video, i did not read the report.Im Scientist S, listen to me, i have a PhD in I know it ALL."

I wouldnt mind discussing the topic, and if i were wrong on any count i wouldnt mind accepting that i was wrong.
But engaging in that with you is pointless as its evident you lack the basic decency and humility to either apologise to the board or even regret the name calling of ISRO which you have been doing all along.

Anyway,
While you are working intensely on the Spreadsheet, could you also solve in 30 minutes a rocket configuration for ISRO to send a manned moon mission and also a manned mars mission ?

Dazzle BRF and ISRO with your spreadsheet rocketry genius.

[symontk]

Prasannasimha ji,

Its being said that we cant hear sonic booms on ground, by you gracefully and by Scientist S rather pompously.


I had btw posted the video to get a break from the vicious cycle.The bangs heard in the said video are what i think are sonic booms.They could be because of transonic shock waves, i wondered .. Until i found the link after a little digging.

Id like you to take a look at this.(The website is gold for those interested in research articles)

http://www.currentscience.ac.in/Volumes/102/01/0105.pdf

.

35 years back, all the SHAR (now SDSC) staff resided & worked in temporary quarters / offices. We visited our fathers quarters every year during summer holiday's. We also had a chance to visit various launch facilities. But later quarters were shifted to Sullerpetta and offices moved to permanent buildings. The reason was that, PSLV / GSLV generate huge amounts of sound. Those settlements would crash down

I heard that even the tribals who are staying in SDSC are provided with very good permanent houses, but they are removed from launch sites before the launch

Sesmic impact I agree, but may be no sonic booms

Having said that, dont think I am supporting Vina's argument about GSLV having capacity for putting a 4 ton satellite by not dragging the spend solid stage. But I do believe that it would be able to do that some time later based on the improvements ISRO will bring in naturally

His spreadsheet might be missing some other key points which ISRO scientists might be knowing

[symontk]

^ As far as costing is concerned this is not an accounting fudging but based on what ISRO is charging at present for commercial launches which are not subsidized but are for profit.

ISRO primarily uses solid motors in atmosphere stage and thus it costs less. other vehicles uses liquid engines. Even in the cases where solids are used, like Ariane 5, the next stage uses much more costlier fuel called cryogenic. None of the active vehicles can match ISRO's cost structure, So that is why US is driving towards reusable engines where they have an advantage, (countries like India don't have as we know about our capabilities, take Kaveri for example)

[navneeet]

ISRO to perform key manoeuvre on Mars Orbiter next year

CHENNAI: With the Mars Orbiter Mission completing two years, ISRO today said it will be doing a "major event" of effecting a manoeuvre on the Orbiter next year to reduce the impact of an "eclipse duration" to allow the spacecraft "survive" for more time.

http://economictimes.indiatimes.com/art ... aign=cppst

[nirav]

35 years back, all the SHAR (now SDSC) staff resided & worked in temporary quarters / offices. We visited our fathers quarters every year during summer holiday's. We also had a chance to visit various launch facilities. But later quarters were shifted to Sullerpetta and offices moved to permanent buildings. The reason was that, PSLV / GSLV generate huge amounts of sound. Those settlements would crash down

I heard that even the tribals who are staying in SDSC are provided with very good permanent houses, but they are removed from launch sites before the launch

Sesmic impact I agree, but may be no sonic booms

Having said that, dont think I am supporting Vina's argument about GSLV having capacity for putting a 4 ton satellite by not dragging the spend solid stage. But I do believe that it would be able to do that some time later based on the improvements ISRO will bring in naturally

His spreadsheet might be missing some other key points which ISRO scientists might be knowing

Thanks for sharing that.

The thing is, the sonic boom if it actually is or if the bangs are transonic shockwaves, it doesnt really matter.Thats not really the crux of the discussion in here.

This whole thing about shrill criticism of ISRO is the problem where ground realities are not factored in while criticizing blindly.

GSLV Mk2 can now be called a reliable launch vehicle only in 2015-16 timeframe.They are working on incremental upgrades to the extent possible.The latest iteration of GSLV Mk2 had a 100 Kg hike in payload as per one of the speeches of thhe scientists post the launch.

Now, before bringing up more discussion points to the table, id like to repeat what i had stated earlier.
Because the US Europeans and Chinese do it doesnt mean India shoulld do it too.

We must take a look first at what we have achieved till date, a capability to launch upto 2500 Kg to GTO reliably.
The GSLV Mk3 isnt operational yet and needs huge amount of work to achieve its mission.

Once thats done, we will possess 3 class of launch vehicles with GTO capacities ranging from 1.5 ton of PSLV, 2.5 ton of GSLV Mk2 and about 4 tons of GSLV Mk3.

A lot of posters criticise ISRO for the alleged inefficiency of our rockets in tonnage to GTO while comparing it with rockets of foreign agencies.

Id like to quote ISROs mission and vision statements.

Vision.

Harness space technology for national development, while pursuing space science research and planetary exploration.

Mission.



Design and development of launch vehicles and related technologies for providing access to space.
Design and development of satellites and related technologies for earth observation, communication, navigation, meteorology and space science.
Indian National Satellite (INSAT) programme for meeting telecommunication, television broadcasting and developmental applications.
Indian Remote Sensing Satellite (IRS) programme for management of natural resources and monitoring of environment using space based imagery.
Space based Applications for Societal development.
Research and Development in space science and planetary exploration.

Keeping in mind the above, and also the actual weights of the satellites Arianespace has launched or will be launching for India, where is the pressing need to have a 6-10 tons to GTO capability rightaway ?

Another important thing, a 2500 Kg satellite launched in GTO in 2016 is way more advanced than a similar sized satellite of 10-15 years back.

All this haggling and hankering for higher payloads must have a definite objective. ISRO is NOT in a race with any space agency. That simply is not its mandate.

Also they have a well defined charted growth path for launchers which will eventually lead to 10 tons to GTO or excess in due course of time.

Unlike us armed with a couple websites and spreadsheets, they actually are in the know as to what their strengths and weaknesses are and most importantly what their mandate is.They study thousands of configurations and finally select a configuration which is in line with what their mandate is.


Their mandate is certainly not going for uber values for ISP or mass fractions or how many mega tons to GTO.

Its time people acknowledge that ISRO is not in competition with Space x or whatever private venture coming out of the US.
They are FOR PROFIT organisations.

ISRO does NOT have that mandate.Their choices will therefore significantly vary with prime focus on their Mission and Vision statements.

Another very very important thing that people who criticize dont consider.
The R&D costs in decision making.

After having spent Billions of dollars and Euros in the space launch business, and developing uber capability rockets what exactly has been their ROI ? In the present moment space launch business is facing tremendous price reduction pressure due to new entrants in the business.

ISRO meanwhile keeps chugging along with their lower mass fraction rockets and keep excelling at meeting the mandate given to it by the country.

[navneeet]

The Mars Atlas by ISRO

http://www.isro.gov.in/sites/default/fi ... as-MOM.pdf

The press release

http://www.isro.gov.in/sites/default/fi ... rowser.pdf

Mars Orbiter Mission Long Term Archive Release Statement

Mars Orbit Insertion on 24th Sep 2014
•
After a 300 days journey in deep space, on September 24, 2014, India's Mars Orbiter Spacecraft successfully entered into an elliptical orbit around planet Mars by firing its 440 Newton Liquid Apogee Motor along with eight smaller liquid engines.
•With successful Mars Orbit Insertion, ISRO became the fourth space agency to successfully send a spacecraft to Mars orbit and India became the first country in the world to do so in its first attempt.
•
May 27, 2015 to July 01, 2015; MOM was behind the Sun as viewed from the Earth and no communication was possible between MOM and Earth. Spacecraft survived in full autonomy mode for a period of 35 days.
•
Mars Orbiter mission experienced a white out geometry between 18th May to 30th May 2016. MOM is built with full autonomy to take care of itself for such a long period. No commanding was carried out on the satellite during the white out period. Payload operations were suspended. The spacecraft came out of White out geometry successfully on the 30th May 2016 and has been normalized for regular operations.

[Varoon Shekhar]

Could someone explain to at least one dumb layman, what the difference is between tomorrow's mission, and the Oct 22/2001 launch of 3 satellites, where one, the Belgian Proba, was placed in a higher orbit than the Indian TES and the German Bird?

I know that in the Oct/2001 PSLV mission, it was the thrusters that were fired in order to lift the Belgian satellite into a higher orbit. Whereas, tomorrow, it is going to be the the fourth stage engine, after releasing Scatsat, that is going to be switched off, then reignited about 2 hours later, to send the 7(?) other satellites into a different orbit. Understood.

So my question is( perhaps a technicality!), is it really accurate to say that tomorrow's mission is the first, where Indian launched satellites are placed in different orbits? Perhaps what they mean, is that it is the first where the engine itself, is turned off, then on again, to send satellites in a different orbit. Also, the difference in the orbits are considerable, whereas for Proba, it was only slightly higher.

Anyway, sounds impressive, best wishes for an eagerly awaited launch tomorrow morning!

[prasannasimha]

The 4th stage itself will be used to deliver the satellites in different orbits so satellite fuel usage will be less also with this the orbits will be significantly different. Firing the 4th stage at periapsis or apoapsis will allow an entirely different orbit. Imagine two elipses sharing one periapsis. That will be how the orbital delivery will differ.

[sooraj]

Why is there no lightning towers surrounding this launch tower?
I can see them around the other launch tower in the background.

[SSSalvi]

@Varoonshaekhar

From ISRO website:

This is the second time that PSLV is launching three satellites simultaneously; in the previous launch in May 1999, PSLV had launched Indian IRS-P4, German DLR-TUBSAT and Korean KITSAT-3. While TES and BIRD was placed in a 568 km sun-synchronous orbit, the third satellite, PROBA, was placed in an elliptical orbit of 568 x 638 km, which was achieved by firing the Reaction Control Thrusters of the fourth stage of PSLV-C3. As all other Indian satellite launch vehicles, PSLV-C3, was launched from Satish Dhawan Space Centre, SHAR on the east coast of India.

The orbit change was achieved in PSLV C3 mission by Reaction Control Thrusters .. which could be different than the actual dual thrusters.

@ Shankas
Sometime back ( around 2 months back ) there was a discussion about Lightning arrestors. One launch pad has 3 of them while the other has 4.

[juvva]

The 4th stage itself will be used to deliver the satellites in different orbits so satellite fuel usage will be less also with this the orbits will be significantly different. Firing the 4th stage at periapsis or apoapsis will allow an entirely different orbit. Imagine two elipses sharing one periapsis. That will be how the orbital delivery will differ.

Just now, heard on the live telecast, that both orbits will be circular.

[Karthik S]

Hope this is will also be usual just normal ISRO day.

[rahulm]

The commentators need some duct tape on their lips.

[SSSalvi]

Scasat will be in 730 km/97.8 deg circular orbit.

Remaining SATs @689 km/98.1 deg car orbit

2nd entity in this specs is inclination wrt equator at ascending node.

However SATs are released near descending nofe

[arshyam]

Sep 26, 2016 PSLV-C35 Successfully launches SCATSAT-1. Seperation of the remaining 7 satellites expected to occur between 11.25 hr IST and 11.28 hr IST
Sep 26, 2016 PS4 Fourth Stage Engine Shut-off
Sep 26, 2016 PS4 Fourth Stage Performance Normal
Sep 26, 2016 PS4 Fourth Stage Engine Ignited
Sep 26, 2016 PS3 Third Stage is Separated
Sep 26, 2016 PS3 Thrid Stage Performance Normal
Sep 26, 2016 PS2 Stage Seperated, PS3 Thrid Stage Ignited
Sep 26, 2016 Heat Shield Seperated
Sep 26, 2016 PSLV-C35 PS1 Stage Seperated and PS2 Second Stage Ignited
Sep 26, 2016 Lift-off Normal

From here: http://www.isro.gov.in/media

(Edited first line with latest update)

[SSSalvi]

Yawwwwwwn .. one more PSLV .. no hitch .. BRFits silent .. Good day

[Singha]

saw it on tv over breakfast...yawned..move on

[SSSalvi]

all over as usual

[Pratyush]

Hope this is will also be usual just normal ISRO day.

it is.

It is boring.

[PratikDas]

Congratulations for being the first to launch into two orbits with one rocket, ISRO!
8/8

[Dilbu]

This so boring. Keep it that way ISRO. Brilliant job as usual.

[prasannasimha]

The circular orbits are achieved by firing at the nodes of an elliptical Al orbit of the 4th stage and any subsequent corrections.

[RKumar]

This launch was more then usual ... excellent job ISRO!!!

[arshyam]

For the record: In a first, PSLV launches eight satellites into two different orbits - Dennis S. Jesudasan, The Hindu

The satellites include SCATSAT-1, a satellite for weather studies, IIT-Bombay’s PRATHAM and PISAT from PES University in Bengaluru.

In a first, Indian Space Research Organisation (ISRO)'s PSLV C-35 rocket on Monday launched a total of eight satellites, for into two orbits.

The 371 kg-weighing SCATSAT-1, a satellite for weather-related studies was placed in the polar sun synchronous orbit at an altitude of 730 km some 17 minutes after the rocket took off from Satish Dhawan Space Centre at Sriharikota.

About two hours later, the rocket placed two satellites from educational institutions (PISAT and PRATHAM), three commercial payloads from Algeria (ALSAT-1B, 2B and 1N) and one each for Canada (NLS-19) and the United States (Pathfinder-1).

Announcing the successful launch of all the satellites from the Mission Control Centre, ISRO chairman A.S. Kiran Kumar said the Monday launch marked a "landmark day" in the history of ISRO.

The rocket was re-ignited twice during its flight to place the set of satellites in a different orbit. Due to the re-ignition, the Monday's launch is by far the longest PSLV launch by ISRO.

Though ISRO has launched several PSLV rockets in the past, this launch is "the first mission of PSLV in which it will be launching its payloads into two different orbits," ISRO said.

SCATSAT-1 with a life of five years, would provide weather forecasting services through the generation of wind vector products.

Students at IIT-Bombay celebrate the launch of 'Pratham', one of the satellites carried by the PSLV-C35. Photo: Vivek Bendre

The 10 kg-weighing PRATHAM by IIT Bombay intends to estimate the total electron count with a resolution of 1km x 1km location grid and PISAT (5.25 kg) from PES University in Bengaluru intends to explore remote sensing applications.

ALSAT-1B is an Earth observation satellite (103 kg), ALSAT-2B is a remote sensing satellite (117 kg) and ALSAT-1N (7 kg) is a technology demonstrator. NLS-19 is a technology demonstration micro satellite (8 kg) and Pathfinder-1 is a commercial high resolution imaging micro satellite (44 kg).

[Neela]

Are there any references to restart capabbility of CE7.5?

AFAIK, there are a pump each for LOX and LH2 which feed to the main turbo pump before the combustion chamber.
Main turbo pump itself is run from preburner exhaust.
I dont know what how preburner runs (something must ignite the preburner)

To have restrart capability, there must be be independent stop/start/restrart control of
- LOH pump
- LH2 pump
- main turbo pump
- (?) control of preburner start/stop and _restart_

[Varoon Shekhar]

Can anyone provide a link to the TV coverage of the launching of the 7 satellites into the lower orbit? Scatsat launch is easily accessible. What about the 2nd phase, where 7 sats were injected into a lower orbit?

[anupmisra]

BIG DEAL!!! Where does that place ISRO against the Baki-SUAR.quam, hain?

[SSridhar]

BIG DEAL!!!

Ignorance is bliss.

[Vivek K]

A proud day!

[SwamyG]

Yawn.....another naarmal day for eesRo. Congratulations, keep it this way. Evolutionary steps towards greatness.

[A Nandy]

http://timesofindia.indiatimes.com/indi ... 519252.cms

Kiran Kumar said assembling of various stages for GSLV Mark III began on Sunday. "We are gearing up for the launch at the earliest."

We have felt the ground shake and the air shattered by the testing of a...
http://er.jsc.nasa.gov/seh/ricetalk.htm

Its a great time to be alive !! Let the ground rumble and the air shatter again...

[SwamyG]

This is a good read with nuggets http://thewire.in/68021/pslv-c35-scatsat-blacksky/

[Varoon Shekhar]

Good article in wire, but repeats the false info that PSLV c1 was unsuccessful. The original error was corrected from the ground

[Varoon Shekhar]

Also needlessly compares PSLV with Delta in flight success rate

[Gagan]

Naarmal naarmal
Everythings Naarmal !
How boring onlee...

Congrats ISRO!

[Bheeshma]

Sorry never seen a more crappy article than the one in the wire. Some low IQ, inferiority complex ridden jholla walla seems to be the author. Don't worry the people in the know , can ascertain the value and meaning of the capability demonstrated. Was thrilled about the GSLV-MkIII launch.

Regarding the GSLV debate, I remember a long time ago I did see an article in newspaper that claimed that the GSLV-II payload could be progressively increased to 3-3.2 tonnes ( like soyuz). But it was in Indian express in print when I was still in college. 2000-2002 time frame.I certainly hope it can be done.

[Indranil]

Regarding the GSLV debate, I remember a long time ago I did see an article in newspaper that claimed that the GSLV-II payload could be progressively increased to 3-3.2 tonnes ( like soyuz).

I am almost certain it can be. GSLV MK2 configuration is not optimum. It does not take a rocket scientist to understand so. But, there are good reasons for the same. Here are some quality posts on the internet.

Question
Much of the complexity of GSLV is reportedly thanks to the cryogenic upper stage. SpaceX Falcon 9 can put satellites (heavier than GSLV) into geostationary orbit without a cryogenic engine. Did ISRO miss a trick?

The question is not that great, but the answers are good.

Arkarup Gupta, Scientist at ISRO SATELLITE CENTRE
Written Jul 11, 2015 · Upvoted by Param Uttarwar, Scientist at Space Applications Center, ISRO

Short answer: ISRO tried a better milage engine as they thought it would cost less for a poor country.
Long answer:
1. SPACE-x designs came directly from NASA similiar to what used for apollo or saturn mission.
2. In space industry design not as important as realisation of design or rather modification of design iteratively during design.
It means for any new tech u have to start with primary concept... duting realisation each failure will ask you to modify design... that mean going back to blackboard with more informatipn than earlier and start afresh.
3. Then each step necessary manufacturinrg process.... new manufacturing process....quality assurance... and quality inspection. This may look trivial but jas a huge impact. i will give you example.
You are designing a rocket body ...U understood u would need specific type of structure with specific quality..also u need a specic screw.... u go out in the market and see no body makes such thing.....and also u are not expert in structure manufactuting process engineering and screw manufacturing ..... So what are your options ???
i. you call for structure manufacturing industry of your country who caters different customer by manufacturing products from raw materials. Ask them to design new process to manufacturr your designed screw or structure.
ii. u look for such industry outside your country
iii. u do it urself .... now how much will you do your self ????? seriously you can not expect that your space company will go to different mine s... collect all raw material purify raw materials....create an intermediate materials with new manufacturing process. then create another product under anothet manufactuting proces...and finally manufacture your screw or structure.
option i had limited capability in india because of overall backward ness of countries manufacturing industry.
option ii either charges huge money or refuses to partner with INDIA showing USA imposed sanction and regulation.
option iii is absurd yet sometimes we did it for a few componet example baryllium diaphragm. BUT we can not do for billions or trillions of such components.
So point no 3 explains major problems faced by ISRO at all level whereas Nasa or space -x face billionth time less such problems.
4. now few things indian industry can supply that too have quality issues ir defect issue ... A defect in structure may not show up before u start using or worse while u are launching. even though u perform rigorous test, u can never find the problem. Manufacturing quality or process quality assurance from the manufacturer company is the assurance that things will work. the components bought from Indian companies are very poor in this regard while american companies assurance sometimes rises to six-sigma level while having average three sigma . Indian companies can barely touches two sigma.
5. we are poor country. govt budget percentage allocation itself is neglible compared to budget percentage allocatipn of USA. now USA budget total itself is many times more of our total budget. which means we use reduced parcentage of reduced budget meaning that budget difference between nasa and isro is hugeeeeeeee. Less fund means less progress in a year.
All these 5 points mandate a fact... Nasa can try new design modify it at will or start afresh at will with completely new design....also at a time parallely developing multiple design.
Where as we struggle yo finalise one concept. take many years to realise one protoype of one concept. modifying takes much more years.. Forget about multiple design realisation parallely.
The 5 explained points are simply against us.
once u understand this fact ..... u now understand between two engine. NASA/ spacex semi cryogenic kerosene engine requires greater amount of fuel. bigger structure bigger control mechanism bigger nozzle to achieve same height and velocity of same weight payload ...compared to cryogenic engines. remember ISRO can attempt developing only one. So to the earlier scientists engineers of ISRO it appeared though added complexity it is better to attempt cryogenic which has (in simple terms )better milage( we indians are obsessed with milage). They could not think that this development will turn into nightmares. Again the 5 points are to be major culprits along with nambi narayan case. Also various other factors slowed down of the development adding problems. Hence ISRO did not miss any trick, its just cocktale of all problems that our country faces today.

Raj Kumar,Worked at ISRO for 4 years
Written Jul 19, 2015 · Upvoted by Syed Naser, worked with ISRO for four years
ISRO inherited its technology from its technological partner - Russia and Russian cryo stage vehicles. Because Russia was only country helping India in technology transfer during 80s-90s.

ISRO did not miss any trick. ISRO's vehicle design are very compatible. If it want to go without cryo, It can develop a different engine (semi-cryo) for upper stage, and first two stages can be used as it is.

Cryo stage handling is very tough. Now even Russia is not using cryo stage, They have shifted to semi-cryo engines, SpaceX is also using semi cryo technology. Which uses liquid oxygen and kerosene instead of Liquid oxygen and Liquid Hydrogen (Cryo). I am sure ISRO is also in process of developing Semi-Cryo engines. And existing design process and learning during development of cryo stage will definitely come to use while developing semi cryo engine.