Bharat Rakshak

symontk: thanks, does non destructive testing include start up and/or a short burn?

ISRO's current engines will be fresh on launch, we will see a difference once RLV comes into picture

How do you plan to recover from a 3rd stage use?.

No.

Radar Imaging has its own advantage that it can see through clouds and measure heights accurately ( which is not possible with Optical Imaging ) but features like vegetation etc can best be detected/interpreted with Optical Imaging. Radar images are more crispy due to the absence of haze caused by fog,dust,heat layers etc.

Each has its own advantages ( and disadvantages ) .

User can use both as supplementary to each other. This really provides a solid mix .. but is difficult. ( e.g. see the 2nd image viz Gangotri in ISROs recent image library from RISAT. You will recognize that the features belong to same area but just try to overlap the images mentally and you see the differences . This is because RADAR has a side looking geometry and its viewing angle may not match the optical satellite viewing angle. Moreover the two may have different heights. Of course the softwares take care of these differences but still..... )

Radar processing is more involved and images are generally costly.

Thanks, SSSalvi.

"If ISRO shares with the jingo a reason to believe that the new ground tests are more comprehensive in scope.."

Isro officials mentioned something about not having particular testing equipment for the D-3 cryogenic engine. Would that be the vacuum environment? Or a grade of wind tunnel? If so, they must be confident about getting around this, or do they now possess the equipment.

S^3 , you had started a thread in the Tech and economy forum ,in which you attempted to teach some basics .. Could you resume posting there again ?

Can't it land similarly to US space shuttle? yes its a challenge and oppurtunity too

ISRO has their own version of Heavy Lift Vehicle(HLV) in the 100t to LEO capability
http://3.bp.blogspot.com/_JRgHKYCaeH4/T ... lide33.JPG

It is completely dependant on the sucess of Semi-cryo which is currently in development. Each booster of HLV will sport 3-4 semi-cryo engines and the core stage with 4 semi-cryo but with ablit uprated thrust than compared to the booster engines.

Currently space-X produces ~8 Merlin eingines/month and they are planning to double the capacity in near future.

Once ISRO`s semi-cryo completes development, we need to produce atleast 12 engines/month considering that the same semi-cryo will be used on GSLV-MKIII replacing the L-110 stage.

Once the semi-cryo engine development is finished all they need is bundling them together for the HLV apart from the development of C-100 cryo-stage which I believe they will master the cryo tech with C-25 development.


http://www.domain-b.com/aero/aero_gener ... ngine.html

And ISRO said it will take them 6 years to finish development and start production from the date of sanction.Which means by 2015 the 2MN semi-cryo will be fully available for launch

http://www.flonnet.com/fl2406/stories/20070406001404300.htm

This article is 5 yrs old but it might as well have been written yesterday. EVERY single word is worth reading. It clearly and succinctly explains cryo vs semi-cryo engines and the unfortunate decisions made at ISRO regarding solid vs liquid propulsion. I have to admit the Chindu blows away the rest of the DDM when it comes to science/defense reporting even if the higher ups are commie traitors.

I would not hold my breath as this is likely to be a complex technology and initial timelines will definitely not be met.

Seems A motivated Western Mole influenced the import of Viking engines, killing of the development of Liquid Propellant Stage.

I would not go that far without evidence.

For ISRO to learn the basics, Viking was the only available game in town at that time:
viewtopic.php?f=3&t=6219&p=1285830#p1285830

Anyways, before CABS/RD56/KVD-1 (an engine the Russians never flew ) acquisition happened, there have been setbacks of ISRO-origin cryo development, with news reports of non-fatal explosions. The risk of a fatal explosion, when using new untested methods were way too high for India's fledgling program. For reference, check out Brazil's or South Korea's struggle with integration and how it affected their programs. Both countries are quite competent in aerospace and got good resources.

As for hush-hush stuff, the lack of a stout counter-intel program like other strategic sector was telling: from the much-maligned Nambi Narayanan to other more private individuals who get affected, no one got any closure after the scandal. Big fak-ups.

The LOX Kerosene combination is used for the most powerful rocket engines including the Saturn and Energia.And i dont think all these developments were unknown to anyone.But whats interesting is ISROs lack of vision.Rocket engines being the work horses, any space faring nation can only build its capabilities on those.

I guess it wont be a good idea to call it lack of vision. US & USSR were big players at the time. We were still trying to get our basics right. It might be more of choosing a safe path.

Whoa Stop it right there. Solid Rockets technology was the quickest way to achieve satellite launch capability which is the ISRO mission. SLV->ASLV.


During 70s ISRO contributed man power/design engineering and monetary resources for the French development of an alternate satellite launcher and developed the Vikin engine which led to the Vikas engine.

Idiot NPAs of the Gary Milhollin ilk say that French trained the Indian engienenrs. How can they train Indians when they were also learning only?

French wanted to create a commercial sat luanch vehicle from scratch and not base it on converted military launch vehicles/ICBMs.

French need resources to create the Viking engine. And India provided them. Plain and simple.

Viaks was the building block of PSLV which was needed as the payloads got heavier and the PSLV was the approach. ISRO has building block scheme of technology development.

BTW Saturn, Energia are all spin offs from Nazi Germany efforts.
And not any self-endowed/gained knowledge of the two super powers.


Easy to throw stones out of ignorance.
After end of Cold War, Al Gore compalined to U.R Rao that ISRO personnel were quitting and working for DRDO.

UR Rao said then Gore should also complain about ISRO people joining US mil-space companies and NASA.

That line stopped after that.

Excellent ramana-ji, cant put it better than that.

This sort of posts needs to be refereed back more frequently. Criticizing Dr Sarabhai and his successors will keep growing, as India's affluence grows. The critics who got used to recent affluence, are not looking at the abysmal budgets and international churlishness that ISRO had to deal with.

Dr Sarabhai and his successors did not have the freedom (including dealing with catastrophic failures with fatalities) nor the money that General Leslie Groves, Sergei Korolov or Werner von Braun had, when they led path breaking programs. If ISRO had a disaster that is even remotely like the Brazilian one, the political will behind the program will weaken considerably. Even the then meager budgets will be slashed if there was any catastrophe around cryogenic propellants. Let alone anything like the Chinese, Apollo1/Shuttle disasters or Soviet ones. Solid boosters and Vikas were the lowest risk strategy at that time and it worked in providing us a reliable capability.

A cursory glance at the big difference in launch frequency of PSLV vs GSLV Mk1&2 will show us the issues with initial setbacks caused by reliability of engines. GSLV launches are yet to gain the confidence for ramping up launches.

Only if we have national leadership who are total dicks, like those of the Cold War sides or China will we see "national programs at all costs". Even the US recently has been pussyfooting around their options, after their version of "ISROs lack of vision" called the Shuttle program.

The best praise from Werner Von Braun for Indian rocketery and missile efforts is quoted in "Wings Of Fire", where he got a briefing from Kalam and gave his feedback.

Will give page number and exact quote by 26th May.

Found this from some blog..

http://sreedhar-abdulkalams.blogspot.co ... ments.html

Braun says,
"America is a country of great possibilities,but they took upon everything un-American with suspicion and contempt.They suffer from a deep-rooted NIH-Not Invented Here-complex,and look down on alien technologies.If you want to do any thing in rocketry,do it yourself."

He continued "SLV-3 is genuine Indian design and you may be having your own troubles.But you should always remember that one doesn't just build on successes,but also on failures.Mere hard work cannot fetch you honor,Building a rock wall is back breaking work.There are some people who build rock walls all their lives.And when they die,they leave behind miles of walls,mute testimony to how hard they had worked.

"But there are others who,while placing one rock on top of another,have a vision.It may be to create a terrace with roses climbing over the rock walls and chairs set out for lazy summer days.Or the rock wall enclose an apple orchard or mark a boundary.What matters is that when they have more than a wall.It is this goal that makes the difference".

"Do not make rocketry your profession or your livelihood-make it your religion,your mission".

with indian babooze and forces.. it is extremely difficult to create a trust model. given that, and the type of risk in rockety is 1000%, what we needed is a reliable safe mechanism to launch our own satellites.

what great responsibilites our leaders had on their shoulders to take the riskiest projects ever., that is actually feeding the nation rich now.

-

take a peek at the intnl aerospace dhaaga- NASA's MER-ed project that failed.. billions gone! they did everything, and failed. top notch level 5 cmmi approaches. double redundant systems including the rovers. they failed on certain critical aspects.. that did not impact their credibility.

-


I hope farmers begin to use ISRO data for value addition, and realize and experience the technology.

No SaiK.
Its a matter of two different views (Neta-babu nexus and Forces) of the real facts.

The UDMH/N2O4 engine decision had the advantage of dual use

Indeed. Sometimes the obvious remains cryptic to many.

Kit bhai and MNji, apologies to quote your points. I need to elaborate from there:



I am assuming that when you quote "can only build its capabilities on those"., you mean the LOX/Kerosene combination.

Now lot of persons on this forums assume that LOX/Kerosene is a very easy path compared to LOX/LOH since only one path is cryogenic and it is easier to compress/cool down and manage LOX at that compared to LOH . Others assume that it is a safe path since Saturn/Energia run on it and of course it is "semi cryogenic"

Let us say both points are very valid., we have large examples of booster rockets running on LOX/Kerosene and since it is only half cryogenic so the range of temperatures are not that extreme.

Now just spare some thought on the Kerosene. Is it the "ghaas tel" which every house hold in India is accumstomed to using that goes in the LOX/Kerosene part? That is take the kerosene from the ration shop and pour those dabbas in the tank for the LOX/Ker engine? Of course not and I am sure you will also point out that you do not mean that Kerosene., since using that Kerosene is idiotic (that is using Ghaas Tel from ration shop is idiotic, which we all agree).

So where does this special kerosene come from? And what is special about this kerosene?

Put it this way, when you burn the ordinary ration shop kerosene (let us call this RSK-1)., you are looking at achieving a max temperature of 300 C (at most) and several time far lesser than that. However for rocket engines, the temperatures are generated in excess of 2000 C and therefore something is required to bring the temperature down. Generally, one of the liquid that fuels the rocket itself is used to cool the engine (its nozzles and everything else that is required to be cooled) down. I will leave up to you to figure out why Oxygen itself is not used exclusively in LOX/Ker engine. Something on the lines of unburnt fuel leaving a lot of smoke is a good hint (and now do not go about designing and manufacturing even at test one which uses oxygen itself as coolant in lox/ker - if you do, then you should get a straight job at ISRO - note this as sillypoint-1).

So now we have to use the RSK-1 as a coolant. The problem is that at high temperatures, definitely at temperatures encountered at rocket engines, RSK-1 has quite a remarkable tendency to polymerize. From high school chemistry we know that your everyday plastics are nothing but hydrocarbon polymers, so assume that thick deposits (of polymers) get stuck in the inner walls of coolant tubes (not unlike atherosclerosis or your kitchen drain getting clogged when you make lots of jalebis and pour the unused oil down the drain). Anyways, as the cooling passages are constricted, there is less flow of coolant and hence subsequent rise in heat and hence more of polymerization (or reverse of polymeration, cavitation because of the fuel breaking down) and subsequent more rise and you get the idea, all resulting in a huge explosion. So instead of the rocket going up, you have parts of it going sideways and maybe taking you up. You may argue (given that you have vision)., that why not have bigger dia. pipes. All I can say is, please go back to sillypoint-1 above.

So at this stage, we know that RSK-1 will not work. So what will work? Of course a fuel which does not cavitate or polymerize under the temperatures & pressures encountered in rocket nozzle. To turn it around, a hydrocarbon fuel has to be designed, developed and produced that meets the above mentioned requirements. By mid-1950s most of the industrial nations had such a design (for HC fuel) ready. It should be noted that by mid-1950s we were not even a decade after independence and the biggest challenge was national integration (for some) and providing food, medicines and clothing for the others. Okay by mid-1970s we had the requirements ready. Keep this in mind that in mid-1970s lot of rail engines were running on coal!

Now let us move forward., we now have the requirements (just like my PM has requirements for my product) for an ideal kerosene that does not cavitate or polymerize under given temperatures and pressures. So how do I produce one? One of the reasons that the kerosene polymerizes is the presence of sulphur. Ideally zero sulphur, but extremely low sulphur content will do. That is if I am given a barrel of oil and told to produce the required kerosene, I have to first eliminate sulphur.

Second, why does HC polymerize? In short, the carbon-hydrogen bonds break down and re-arrange themselves into more complex molecules. I need to avoid that, and find an HC bond molecule do not break down and reform into undesirable complex polymers but remain a desirable complex polymer. That is alkenes and aromatics (ethylenes and benzenes for the aam abdul) should be taken out of the equation. That is take a barrel of oil, remove sulphur, remove ethylenes (and its more complex analogues), remove benzenes (and remove its more complex analogues). Basically move towards classes HC polymers like ladderanes. Now all of the above fractionalization and distillation has to be done on a barrel of oil. Can any barrel of oil do? Of course not, you cannot just take a barrel of oil from any oil field and dump it in your refinery and produce the above mentioned rocket fuel grade kerosene. The barrel of oil has to be carefully sourced and there are only very few oil fields in the world that source such high quality crude. BTW, in the late 1970s, the oil shock hit us. Heck we did not have diesel to run our cars and here we are talking about sourcing oil from a select oil field! Basically the crudes should have very high napthene content.

So one has to source a barrel of oil and process it to meet the requirements as laid down in US mil spec MIL-R-25576 (or its Russian, Chinese or Indian equivalent). Again that spec may not be completely open source and one has to spend resources that comes to that spec. To come to that spec, one has to have experience in rocket engines that use some kind of LOX/Kerosene to do sand box testing. Here if you do not have one, developing other is a big hassle.

Now by mid-80's when ISRO was taking off, did it have anything other than the requirements in hand. The answer is no. Since one just does not have to find an oil field, but have to find several such so that in case of disruption from the oil field, your space programme does not come to a halt. After sourcing from several such oil fields, one has to develop (design and manufacture) a refinery which can take several such feeds and produce the kerosene (called RP-1) that meets the above specification. Now what were the requirements for ISRo in a given year? Let us be charitable and say 10 tonnes of such fuel (in 80's and well into 90's). Let me bump it to say 100 tonnes of such fuel. So for producing 100 tonnes of such fuel, I will need say 10,000 barrels of oil a year and set up a refinery which processes that. This looks like an extremely costly proposition, since first of all ISRO is not in oil refining business and there is no private or public player (in India) even now that is willing to produce such a miniscule amount just for ISRO at a reasonable cost. Neither was India in a missile-arms race that the refiner could sell the product to Army, Air-force or Navy for their missiles or even their tanks or engines which could be based on jet turbine.

So what does ISRO do? Definitely the LOX/Kerosene is not a cheaper route. Further, the variables in achieving semi-cryogenic engine (delays, complexity etc) is same as one for the cryogenic engines. Further there is no supply constraint on LH2. Since, there is no kerosene that can be sourced for the LOX/Kerosene route., instead of going the LOX/Ker route, ISRO wisely decided to go for the LOX/LOH route. Infact, once the LOX/LH2 engine can be developed, one can come back and look at the launch requirements and if the refininig industry has progressed, can start sourcing small amounts of RP1 equivalents.

Further, hypergolic liquid engines will not be going away - they are excellent for start/stop requirements and hence excellent for stationing and orbit maintainence activities.



Going for LOX/LOH or developing your next generation rocket fleet on scaled liquid engines is not a safe path. It was the only path due to several other constraints which are difficult to comprehend in the first place.

And it is not about vision. Whatever the shortcomings of ISRO, one thing it does not have is a shortcoming of vision. At the end of the day, ISRO is answerable to the parliament and its "vision" is tailored and trimmed by the requirements of the parliament and more importantly its budgetary constraints.

I had a friend in school, he had a remarkable vision. He wanted to emigrate to "gelf" and find a rich oil sheikhs' daughter to marry so that by marriage he will inherit wealth and not work for life. So when kit bhai goes about complaining ISRO's vision., his sight does not go beyond his own' keyboard.

PS:Edited to fix a minor grammatic quibble

Question is simple - can UDMH/N2O4 engines be scaled up for higher payloads easily compared to LOX/Kerosene engines?

BTW, most things are clear in hindsight onlee.

Yes. However more than scaling, clustering is preferred.

It may look "hindsight is 20/20" however there are times when certain courses present itself. Given that LOX/Kerosene is going to be tougher problem and that the Indian rocketry was just getting started, several factors are combined to reduce complexity. Did we have proven rocket designs? Did we have proven rocket designers in the first place? Did we have appropriate range? Appropriate telemetry stations? In a way, comparing ISRO to NASA is a wrong thing. ISRO should be compared to rocket organizations from the following countries: Brazil, China, South Africa. Russia is out because of the technologies it got via WWII and also because of the space race and the soviet's strategic push.

So it boils down to ISRO coming down to comparison only with China. Yes, Chineese space industry has several achievements to its credit and also several spectacular failure, a fraction of which is not even thinkable in the Indian context.

Hence saying "20/20 and all that" is glossing over the hard work and more importantly the hard decisions the organization had to make. ISRO has its faults, it has not cultivated a segment of politicos who are its prime supporters in parliament. That way ISRO can count on some "internal pressure" irrespective of any government to drive its agenda.

I think you are getting it wrong. ISRO going the UDMH/N2O4 route and not LOX/Kerosene may look wrong in hindsight (solely in terms of payload delivery capacity - and here also you are saying that clustering UDMH/N2O4 engines is easier than scaling LOX/Kerosene) but may have seemed right going by their technology levels at that time and capability available to them at that time.

So saying that hindsight brings clarity is not glossing over ISROs hard work, quite the contrary. Perhaps it was not evident to you.

It's a vacuum testing chamber that we lack. The upper stages, which operate at such conditions, should also preferably be tested under similar conditions. Ofcourse, specs for vacuum environment operation can be calculated following testing under near-normal conditions but it still does not guarantee similar performance for each and every component in its operating conditions.



There is no concrete answer to that question as both are complex processes depending on many other things than just the fuel/oxidizer mix. It's not scaling up of engine thrust that I am looking at, rather the ability to cluster engines together. We had the hypergolic engine technology from the 80s and yet, the L110 on Mk-III is the first Indian stage to use a cluster of engines. Reason?? Many. Requirements, simplicity etc. The thing is that we did not experiment a lot with the Viking technology that we got from the Europeans and in a way it did delay our development of semi-cryo/cryo engines.

ISRO didnt had necessary infra to develop semi cryo 40 years back. Even now its struggling with cryo. Also there is nothing wrong in going for solid motors. If the comparision is made with satrun engines, you can compare with space shuttle too. It uses solid motors. But key thing is that, its reusable which is where ISRO is also concentrating.

having said that, knowledge generated for semi-cryo engine develpoments can improve the vikas engine thrusts which will be a added advantage

90% of the Phobos Grunt was a Completely New Technology Deployed for the First time. Russia should Plan a Phobos 2 Mission. Maybe that is Why Russia is charged up for Chandrayaan 2 Lander after the Phobos Grunt Debacle!

It seems the GSLV is ready!

First satellite for armed forces to be ready in a month | TOI

Unless it's another PSLV into GSO. But yes, probably GSLV, which means they are very confident of the Indian cryogenic engine. Excellent!

they did not say the launch vechile, it could from Ariane 5 rocket from french guiana

Would they use an Ariane for a dedicated surveillance satellite?

because indian engineers will be there to monitor the situation during mating. other than some stuff like weight and volume the Ariane5 wont care because payloads are only powered on after the injection...they go up inert.

I strongly feel it will be proven Ariane5 rather than take a big risk with another GSLV. GSLV needs to prove itself with inert or educational pkgs for 3 consecutive flights before we risk more blood and treasure payloads

PSLV pushing it to GTO is a possibility if the sat is light like 250kg perhaps

PSLV can push about 1500 kgs to GTO.

neither of upcoming PSLV launches mentions milsat.

PSLV C-20 with Indo French satellite SARAL and four small satellites would be launched in October, 2012 and PSLV C-21 with a commercial payload SPOT, a French satellite on earth observation this August, he said.