Indian Space Program Discussion

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Re: Indian Space Program Discussion

Postby Vipul » 18 Jan 2009 02:15

ISRO begins work on Chandrayaan-II project.

CHENNAI: ISRO has begun working on the Rs 425-crore second unmanned moon mission to be launched by early 2012 following the success of Chandrayaan-I, a top ISRO official said here on Staurday.

Chandrayaan-II will focus on soil and mineral exploration on the lunar surface with the help of a robotic device and send back data, Chandrayaan Project Director Mayilsamy Annadurai told reporters here.

The work had begun on the project and it was likely to be launched by end of 2011 or early 2012, he said.

ISRO plans to send a manned flight to space in 2015 and the manned mission to the moon in 2020, he added.

About Chandrayaan-I, he said it has beamed 40,000 pictures since its launch.

The stakeholders of the project would meet soon to discuss the information beamed by India's successful lunar mission, Annadurai said.

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Re: Indian Space Program Discussion

Postby Arun_S » 18 Jan 2009 06:35

A krish wrote:Efficiency of GSLV-Mk III

The question has been bugging me for days and I decided to compare Mk-III with some launch vehicles. I know that there was a discussion on the capability of Mk-III and the conclusion was that it could launch about 6-7 tons to GTO and 15 tons to LEO.............................................

Now, we are hearing official statements from ISRO saying that it's capability will be lesser than or equal to 10 tons to LEO and 4 tons to GTO. Conformation from officials------------
http://www.domain-b.com/aero/space/satellites/20090101_gslv_mark-3.html
http://www.telecommagazine.com/newsglobe/article.asp?HH_ID=AR_4726 etc etc etc

*I was quite surprised to see some of the other launch vehicles in this payload category. The GSLV-Mk III weighs in about 630,000 kg.

*The American Delta-IV Medium has a payload capability of 4 tons to GTO and 9 tons to LEO. It weighs at around 250,000 kg

*The European Ariane-4 Heavy(retired) had a capability of 4.5 tons to GTO and 8 tons to LEO. It had a mass of 470,000 kg.

*The Japanese H-II (retired) had a payload capability of 4 tons to GTO and 10 tons to LEO. It's overall mass was surprisingly 260,000 kg

*The Chinese Long March-2E(A) has a capability of about 3.5 tons to GTO and 9 tons to LEO. It's overall mass is 462,000 kg.

These launch vehicles have almost the same payload capability as of the GSLV-Mk III. Yet Mk-III's overall mass is 630,000 kg.
Japan's present H-IIA Heavy version has a payload capability of about 6 tons to GTO and 15 tons to LEO with an overall mass of 445,000 kg i.e about 50 tons more than the present GSLV. ( Truly Whopping ) :eek: :eek: :eek:

Even in it's final form GSLV-Mk III it's capability is predicted to be 6 tons to GTO and 15 tons to LEO.

I am really not criticizing GSLV-Mk III but I just want our ISRO to make GSLV-Mk III a efficient heavy-lift vehicle for our future manned missions and also for greater competitiveness in the commercial market. Let's hope we get an efficient heavy-launcher in GSLV-Mk III.

A krish: No surprise. Did you pay attention to their liquid fulled booster stages?

Due to very lean ISRO budget since inception to 2006, ISRO chose to not put any effort on semi-cryo motors. All resources were channeled into solid fuel stages and liquid fueled motors limited to Vikas family(earth storeable liquid fuel).

The large differences in MTOW that you notice is because the other nations went full throttle in rocketry for military applications (civil was a after thought) where money was a secondary consideration and of course they were not chained in the 3 and 4 letter love fest called MTCR (and shitty bitty etc.) that special love was only reserved for Yindu India; thus all their spacecrafts use Cryo or Semi cryo engines starting from their boosters.

ISRO finally got funds to work on semi cryo engines 2 years ago. Future versions of GSLV will see the L110 stage replaced by a semi-cryo and you will find that GSLV transform into a heavy lifter like today's Ariana. But there is serious possibeility that ISRO's hypersonic Avatar based crafts will succeed like magic and make expendable rockets like GSLV-Mk3 reserved for only very heavy payloads. In fact the push for HSTV/Avatar is precisely driven by engineering and cost issues of a big & heavy launch vehicle. Make it smaller and cost goes down faster; make it re-usable and cost down even faster.

So if you now compare other countries rockets that only used solid or earth storeable liquid fuel, you will get a righful comparision w.r.t. GSLV-1 and GSLV-III, and I think you will be pleased with the numbers.

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Re: Indian Space Program Discussion

Postby ss_roy » 18 Jan 2009 06:52

I am sorry to say that this response is factually incorrect. Compare GSLV-3 with Titan-3 (I have in previous posts on this thread). Pay close attention to the fuels used, gross weights, mass fractions/ thrusts/ specific impulses. If the GSLV-3 cannot better Titan-3, we have a problem!

PS- Almost all chinese launchers use hypergolic liquid fuels, as did Ariane-4 (except for the 3rd cryogenic stage).

Ariane-4 used 4 viking (vikas) engines for the 1st stage, 1 viking engine for the 2nd stage, and one 70kN Cryogenic engine for the third stage (which france was willing to sell to India- along with the technology). It also used solid or liquid boosters similar to the PSLV and GSLV. If the GSLV cannot be modified to equal the performance of the Ariane-4... you know..

The real problem is Indian attitudes that discourage modifications and tinkering for the fear of failures! For example- Why not redesign the main solid fuel motor of the PSLV/GSLV to burn an extra 20-30 seconds. Is it so hard??
__________
So if you now compare other countries rockets that only used solid or earth storeable liquid fuel, you will get a righful comparision w.r.t. GSLV-1 and GSLV-III, and I think you will be pleased with the numbers.

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Re: Indian Space Program Discussion

Postby Sanjay M » 18 Jan 2009 07:02

Well, just as long as India is cheaper and reliable, it can grab launch-market share and hope to evolve its platform in the meantime.

The payload clients don't care about mass-fraction, etc, as long as it gets their full payload up there reliably and cheaply.

Meanwhile, I wonder what payload/performance stats will be achieved by RLV and semi-cryogenic engines?

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Re: Indian Space Program Discussion

Postby KrishG » 18 Jan 2009 14:38

I know that Delta-IV and H-II use Liquid Hydrogen in the core stages also that's why their mass is low. I would put GSLV- Mk III in the same slot as Titan-3C specifically because it also used huge solid boosters. Out of the 630,000 kg about 480,000 are is the solid boosters. The Titan-3C had a mass same as GSLV-Mk III. The GSLV-Mk III could only be ahead in the fact that it uses a Cryogenic upper stage.

There's also a lot of debate about the empty weight of the Cryogenic stage which was stated as 5 tons in the previous posts. With a 5 ton empty weight the GSLV-Mk III can hardly put 3 tons tons to GTO. With a 4 ton empty weight we could expect GSLV-Mk III's capability to be about 4 tons to GTO and 13 tons to LEO. Slightly large payload to GTO than Titan-3C due to the Cryogenic stage.

I think by replacing the current 2 Vikas Core stages with a large Cryogenic core stage GSLV-Mk III would become more comparable to Ariane-5 in terms of payload capability. The specific impulse of UDMH is low and in the present configuration the Mk-III's core stage has a specific impulse of about 300 sec and a thrust of around 1400 kN.

Anyway, a slightly more powerful Cryogenic upper stage with a a Cryogenic core stage would really make Mk-III a true heavy lifter capable of 20 tons to LEO. The Cryogenic core stage may cost a lot but it would be a good investment.

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Re: Indian Space Program Discussion

Postby Arun_S » 18 Jan 2009 16:06

A krish wrote:There's also a lot of debate about the empty weight of the Cryogenic stage which was stated as 5 tons in the previous posts. With a 5 ton empty weight the GSLV-Mk III can hardly put 3 tons tons to GTO. With a 4 ton empty weight we could expect GSLV-Mk III's capability to be about 4 tons to GTO and 13 tons to LEO. Slightly large payload to GTO than Titan-3C due to the Cryogenic stage.

Of late did not have time to look/participate at the previous thread, pls indicate what is the basis for the 5 ton empty weight cryo upper stage of GSLV-Mk III.

I think by replacing the current 2 Vikas Core stages with a large Cryogenic core stage GSLV-Mk III would become more comparable to Ariane-5 in terms of payload capability. The specific impulse of UDMH is low and in the present configuration the Mk-III's core stage has a specific impulse of about 300 sec and a thrust of around 1400 kN.
Yes use the ROCKSIM and you can see physics play out the rocket configuration changes you propose.

Anyway, a slightly more powerful Cryogenic upper stage with a a Cryogenic core stage would really make Mk-III a true heavy lifter capable of 20 tons to LEO. The Cryogenic core stage may cost a lot but it would be a good investment.
The name of the game is the mass fraction of upper stage, not as much the need of more powerful C25 stage.

ss_roy wrote:The real problem is Indian attitudes that discourage modifications and tinkering for the fear of failures! For example- Why not redesign the main solid fuel motor of the PSLV/GSLV to burn an extra 20-30 seconds. Is it so hard??

AoA. Pls enlighten us on how much more GTO payload capacity will increase with the "main solid fuel motor of the PSLV/GSLV-1 to burn an extra 20-30 seconds"? I hope it will make it comparable to the its peers in your consideration. Surely that will not be hard to determine.

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Re: Indian Space Program Discussion

Postby Shankar » 18 Jan 2009 16:33

As the central element of Ariane 5, the core cryogenic stage serves as one of the launcher's key propulsion systems.
It carries a propellant load of 132.27 metric tons of liquid oxygen and 25.84 metric tons of liquid hydrogen to feed the stage's Vulcain main engine.

The Vulcain burns for just under 600 seconds, providing up to 116 metric tons of thrust in vacuum.
The stage has an overall length of 30.5 meters from the Vulcain main engine's nozzle to the forward (upper) skirt.
Its dry mass is 12.2 metric tons, and the liftoff mass with its load of cryogenic propellant is 170.3 metric tons.
After completing its propulsive mission, the empty stage is commanded to reenter the atmosphere for an ocean splashdown.
Ariane 5 utilizes two solid boosters, each standing more than 30 meters tall with 237.8 metric tons of propellant. The boosters are ignited on the launch pad once the main cryogenic stage's Vulcain engine has stabilized its thrust output.
They deliver more than 90 percent of the launcher's total thrust at the start of flight and burn for 130 sec. before they are separated over a designated zone of the Atlantic Ocean.

The booster stage’s solid rocket motor is made up of three segments: the 11.1-meter-long aft (lower) segment, which is loaded with 106.7 metric tons of propellant; the center segment, with a length of 10.17 meters and 107.4 metric tons of propellant; and the 3.5-meter-long forward (upper) segment, loaded with 23.4 metric tons of propellant.

A propellant mix of 68 percent ammonium perchlorate (oxidizer), 18 percent aluminum (fuel), and 14 percent polybutadiene (binder) is used in the solid rocket motors.
The combustion process is initiated by a pyrotechnic device, and the solid propellant burns at a radial velocity (from the center outward) of approximately 7.4 mm/sec.
Flight control is provided by the boosters' movable nozzle, which is driven by hydraulically-controlled servoactuators.



As Arun said the essential difference if the large cryo core stage of ariane 5 compared to modest cryo upper stage of GSLV MK 3 . ariane 5 carries almost 160 ton of cryo proellant compared to 25 ton projected for GSLV mk3 .The high specific impulse of lox/gh2 system compared to in solid booster i think make the difference

in total mass to payload ratio . Anyway some day the mk3 can be modified to lift 6 ton plus in geo transfer orbit -I think

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Re: Indian Space Program Discussion

Postby KrishG » 18 Jan 2009 17:19

O.K. If not a Cryogenic core stage we could have built a LOX/ RP-1 engine for Mk-III. It is cheap and also has more specific impulse than UDMH and is earth-stored liquid.

Both the Russians and Chinese use Kerosene(RP-1) extensively in their present and future rockets. We need a efficient and low-cost core stage which means that using Kerosene would be a logical solution compared to the expensive Cryogenic engine.

If a Cryogenic Core stage for Mk-III was not a viable option than the next logical choice should have been LOX/Kerosene engine both in terms of cost and specific impulse. We have hardly started research in such engines while they are the cheapest and best substitutes. It's only last year that we started working on the Semi-Cryogenic engine. Hope, it would come about soon.

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Re: Indian Space Program Discussion

Postby Gerard » 18 Jan 2009 21:07


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Re: Indian Space Program Discussion

Postby Sanjay M » 18 Jan 2009 23:02

Methane has been discovered on Mars

http://blog.wired.com/wiredscience/2009 ... thane.html

http://www.latimes.com/news/nationworld ... 3221.story

http://www.npr.org/templates/story/stor ... d=99458503


Image


Since ISRO is soliciting ideas for an upcoming mission to Mars, I think that such a mission should definitely try to look for signs of life. So perhaps it should include instrument packages specifically useful for detecting methane emissions from the Martian surface.

In particular, mass spectrometry which provides isotopic breakdown may be a good way to discern between methane that has been biologically-produced versus geologically-produced.

http://www.astrobio.net/news/index.php? ... e&sid=3004

Biological processes favor the lighter isotopes, while for geochemical processes it doesn't matter so much. A new type of portable hyper-sensitive mass spectrometer will then reveal the isotopic makeup of the martian methane.

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Re: Indian Space Program Discussion

Postby ss_roy » 18 Jan 2009 23:07

For the GSLV-1, that is fairly easy..

If the solid motor burnt for say 135-140 seconds (doable) and the Vikas Engines in the first stage were also set for 135-140 seconds- there would be no dead weight! You could then increase the fuel loading of the second stage by 10-15 tons and thereby increase burn time from 160 to 220-230 seconds. Add up the thrusts and weight fractions- you will see what I am talking about.

The new solid motor would be a longer S139.. say a S175 or S180

The result would be 0.5 GSLV-3 (almost). Thus you could launch anything upto a heavier version of the Soyuz (8 tons LEO) right now.. instead of waiting for 4 years and development of a new GSLV-3.

Now this 'GSLV-HP' would be almost 460-500 tons.. but it could still be launched from existing facilities...

AoA. Pls enlighten us on how much more GTO payload capacity will increase with the "main solid fuel motor of the PSLV/GSLV-1 to burn an extra 20-30 seconds"? I hope it will make it comparable to the its peers in your consideration. Surely that will not be hard to determine.

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Re: Indian Space Program Discussion

Postby KrishG » 18 Jan 2009 23:27

For the GSLV-1, that is fairly easy..

If the solid motor burnt for say 135-140 seconds (doable) and the Vikas Engines in the first stage were also set for 135-140 seconds- there would be no dead weight! You could then increase the fuel loading of the second stage by 10-15 tons and thereby increase burn time from 160 to 220-230 seconds. Add up the thrusts and weight fractions- you will see what I am talking about.

The new solid motor would be a longer S139.. say a S175 or S180

The result would be 0.5 GSLV-3 (almost). Thus you could launch anything upto a heavier version of the Soyuz (8 tons LEO) right now.. instead of waiting for 4 years and development of a new GSLV-3.

Now this 'GSLV-HP' would be almost 460-500 tons.. but it could still be launched from existing facilities...


Let's try to avoid solid stages except in the boosters. Anyway, the Soyuz-derivative will take 6-8 years to be completed. I am more concerned about our indigenous Orbital Vehicle that's going to be launched on Mk-II.

The fact that we are using GSLV-Mk II for launching Orbital Vehicle also puts a lot of restrictions on OV. I would probably suggest converting GSLV- Mk II into a 2 stage rocket with a semi-cryo core stage with the current liquid strap-on boosters for the high specific impulse. A cryo-upper stage wouldn't be such a big requirement for manned missions so we get a cheaper and more LEO capable vehicle in GSLV-Mk II. A two-stage Mk-II also gives us the liberty to strengthen the core stage specifically to launch 6-8 tons of payload into LEO.
So, we can add an orbital module to OV and also launch the Soyuz-derivative.

We should use solid propellant only in the booster stages due their relatively low specific impulse especially in mid-heavy and heavy lift vehicles.

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Re: Indian Space Program Discussion

Postby Arun_S » 18 Jan 2009 23:48

ss_roy wrote:For the GSLV-1, that is fairly easy..

If the solid motor burnt for say 135-140 seconds (doable) and the Vikas Engines in the first stage were also set for 135-140 seconds- there would be no dead weight! You could then increase the fuel loading of the second stage by 10-15 tons and thereby increase burn time from 160 to 220-230 seconds. Add up the thrusts and weight fractions- you will see what I am talking about.

You made the claim, so the onus is on you to add up the thrusts and weight fractions- and tell us what you are talking in terms of payload increased of this rocket that you envision.

As an aside, the following claims are factually incorrect:
1)
If the solid motor burnt for say 135-140 seconds (doable) and the Vikas Engines in the first stage were also set for 135-140 seconds- there would be no dead weight!

    I am loss to comprehend. If one can tell ISRO how to make increased solid propellant fuel and liquid fuel tank without increasing dead weight those ISRO dumb heads will surely mend their ways.

2)
You could then increase the fuel loading of the second stage by 10-15 tons and thereby increase burn time from 160 to 220-230 seconds. .... .. . . The new solid motor would be a longer S139.. say a S175 or S180

    A.) Increasing fuel loading of S139 solid stage by increasing 10-15 tonne will make it S154 and does not square up with purported 175 or 180.
    B.) Lengthening the motor does not increase burn time. Burn time is determined by fuel chemistry, diameter of the stage and the grain shape.
    C.) Increased burn time does not increase impulse generated by a motor (the fuel mass and its ISP determine the impulse). Increasing burn time means reduced burn rate & thrust, and its effect will be counter productive because gravity acting for longer duration effectively result in vehicle losing effective impulse.

Please help educate us the physics of this rocket science and quantitatively tell us how payload will increase.

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Re: Indian Space Program Discussion

Postby KrishG » 19 Jan 2009 00:59

If the solid motor burnt for say 135-140 seconds (doable) and the Vikas Engines in the first stage were also set for 135-140 seconds- there would be no dead weight!


I agree with Arun_S. The only way to decrease dead weight without affecting the payload capacity is by using more lighter and strong composites to construct the rocket. Increasing the burn time doesn't help in any way and is not related. Read this ------------
http://adc.gsfc.nasa.gov/adc/education/ ... solid.html


I am still for a 2-stage GSLV-Mk 2 with a single powerful core stage of either Kerosene (Semi Cryo) or UDMH (less specific impulse than RP-1).

Let solid propellant be used only for booster stages of heavy and mid-heavy vehicles and in small launch vehicles.

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Re: Indian Space Program Discussion

Postby ss_roy » 19 Jan 2009 04:44

Arun,

I will post the detailed calculations later.

Let me give you an idea about my concept though

Stage 1= 4 Vikas Engines (135-140s) + 1 SRB (135-140s)

The biggest problem with the current GSLV setup is that the SRB burns for a shorter time (107-109s) than the Vikas Engines (160 and now 140s), creating a dead weight of about 30 tons that has to be dragged along with the craft till Stage 1 burns out and falls off.

I have looked at other SRBs and I can see that they can be made to burn longer (130-140s) ex- Titan-4 SRBs. There are two solutions to this problem- either increase the fuel load by 25-30% (longer/fatter booster with more fuel segments) or a slower burning booster with less thrust but longer burn. Solution- Add one more segment to the S-139 motor (maybe 30 tons more propellant?) or a slower burning S-200 motor. Either way you get a longer burning booster, though the S200 modification is more trickier (fuel manufacturing process changes).

Now you can match the burn times of the Vikas boosters and the SRB- so there is no deadweight. This allows you to add about 15+ tons of fuel for the 2nd stage- Vikas engine stretching its burn time from 160s to 240 s (maybe even more?).

Stage 2 = Vikas Engine with 55-60+ tons of fuel.

This situation is very doable and would be essentially like a 0.5 GSLV-3 'core stage'. The engines have been tested and would be identical to those used in GSLV-3, only the fuel tanks would be like a fatter/ longer version of the conventional vikas engines.

Stage 3 = Hypergolic or LH2/LOX Engine- Depending on your preference for a LEO or GTO mission. The Hypergolic Engine for Stage 3 (say about 100-200kN) might have to be developed- but it would essentially be a scaled down vikas engine.

With this design you can reuse many existing components/ technologies/ systems to create a much better launcher.

The end result is that you a storable/ easy to deploy/ cheap GSLV modification that had a better LEO/ GTO payload. All with a few minor changes- compared to designing a new launch vehicle. It will be about 60-100 tons heavier, but with the same basic shape and features. The height/ mass distribution changes could be kept minimal with clever engineering.

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Re: Indian Space Program Discussion

Postby ss_roy » 19 Jan 2009 08:17

Just use this SRB as the core stage of a newer GSLV- might want to improve the burn time to 135-137 s instead of 132 s.
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Re: Indian Space Program Discussion

Postby ajay_ijn » 19 Jan 2009 08:55

ss roy, do u have any info on costs of developing/manufacturing/handling different fuels, which is the best of all -Solid or Viking type Liquids or Cryos?.

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Re: Indian Space Program Discussion

Postby ajay_ijn » 19 Jan 2009 09:02

Aaj Ki Taaza Khabar from ISRO
Work on Chandrayaan-II has begun, GSLV Mark-III to launch 2700 kg orbiter
CHENNAI: Work on the engineering aspect of Chandrayaan-II has begun and it will be launched by 2012, said Mayilsamy Annadurai, Project Director Chandrayaan-1, on Saturday.

“The total cost of the project is Rs. 425 crore,” he told journalists after calling on Tamil Nadu Chief Minister M. Karunanidhi at his residence here. He said though the lander-cum- rover was an Indo-Russian joint venture, Russia would share the major responsibility for the lander-cum-rover. “The orbiter will be ours,” he added. The launcher will be GSLV Mark III.

The Chandrayaan-II will have an orbiter (spacecraft) besides a lander-cum-rover. After the spacecraft reaches the lunar orbit, the lander-cum-rover will release from it and soft-land on the Moon by means of a powered descent.

Mr. Annadurai said the entire orbiter would weigh 2,700 kg. Asked about his meeting with Mr. Karunanidhi, he said, it was a courtesy call. “I thanked him for his congratulatory messages,” he said.

I hope its not DDM messing with Mark theens and dos. orbiter is said to be pretty much same as CY-1, So the rest 1700 Kg must be lander+orbiter.

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Re: Indian Space Program Discussion

Postby ss_roy » 19 Jan 2009 09:08

Solids and hypergolics are the cheapest, unless you live in the USA (hypergolics and environmental laws) Proton, Titan-2, Titan-3/4, almost all Chinese launchers- excellent reliability.

RP-1/LOX is quite cheap and easy [Fuel, facility and engines]- Soyuz, Zenit, Delta 2, Atlas 5 Launcher

LH2/LOX is problematic because both fuels are cryogenic, but have different temperature/storage requirements. LH2/LOX engines are also tempermental.

Solids and hypergolic based launchers have the highest reliability.. bar none. A good RP-1/LOX launcher (soyuz) is also very good, but failures can be catastrophic. LH2/LOX as main stage engines are horrendously expensive and touchy.. (significant risk of failure and delays)

Overall-
Solids+Hypergolics are the cheapest and least likely to blow up.
If you have experience with them, RP-1/LOX are almost as good but blowups are like small nuclear weapons.

LH2/LOX are good on paper, but are best reserved for upper stages. Blowups are horrifying.

ss roy, do u have any info on costs of developing/manufacturing/handling different fuels, which is the best of all -Solid or Viking type Liquids or Cryos?.


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Re: Indian Space Program Discussion

Postby ss_roy » 20 Jan 2009 04:12

An interesting youtube compilation of launch disasters. I have to say that India has done OK so far..

Maybe ISRO should play this clip whenever "english language media" critics question the engineering competence of indian scientists.

http://www.youtube.com/watch?v=wNsJUmFrUCA

ISRO could use a little more imagination, daring and mistakes, though..

Another video

http://www.youtube.com/watch?v=13qeX98tAS8

Chinese rocket disaster

http://www.youtube.com/watch?v=8_EnrVf9u8s

what GSLV-3 might look like

http://www.youtube.com/watch?v=4CviGrYuAhM

How a Titan 3 explosion looks like

http://s76.photobucket.com/albums/j17/TomcatFanatic123/Titan%2034D%20explosion%20pictures/

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Re: Indian Space Program Discussion

Postby sanjaykumar » 20 Jan 2009 07:17

Methane on three Martians areas is big news. Carbon isotopic ratios are presumably similar to earth cf inner planets but by no means a valid a priori assumption.

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Re: Indian Space Program Discussion

Postby Yogi_G » 20 Jan 2009 07:46

ss_roy wrote:An interesting youtube compilation of launch disasters. I have to say that India has done OK so far..

Maybe ISRO should play this clip whenever "english language media" critics question the engineering competence of indian scientists.

http://www.youtube.com/watch?v=wNsJUmFrUCA

ISRO could use a little more imagination, daring and mistakes, though..

Another video

http://www.youtube.com/watch?v=13qeX98tAS8

Chinese rocket disaster

http://www.youtube.com/watch?v=8_EnrVf9u8s

what GSLV-3 might look like

http://www.youtube.com/watch?v=4CviGrYuAhM

How a Titan 3 explosion looks like

http://s76.photobucket.com/albums/j17/TomcatFanatic123/Titan%2034D%20explosion%20pictures/



the easiest way would be to say that EVEN Israel launches their satellites on Indian rockets and that would immediately silence them. :lol:

Seriously, while Israel tries to stabilise the Shavit rocket ISRO has made great strides and left it far behind...ISRO has a million things to be proud of and a billion people are proud of it :)

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Re: Indian Space Program Discussion

Postby Nitesh » 21 Jan 2009 14:49

ISRO may allow school students to use its laboratories soon

Chennai: The Indian Space Research Organisation (ISRO) may soon allow school students to use its laboratories to carry out project work.

This was informed by Mayilsamy Annadurai, Project Director of Chandrayaan-I.

Annadurai said, "The growing interest among school children on space research after the success of Chandrayaan-I will give an impetus to space research in future."

"Now, around 200 graduate and postgraduate students are allowed to use ISRO lab to carry out their project work," added Annadurai.

Interacting with students Dr. Annadurai answered queries raised by students.

"As the success of Indian space research has come at a time of the slump in the IT industry, many bright young minds in the country will start to think of a career in space research," he added.

Dr. Annadurai also said that the country could achieve the long term goals of space research in a short span of time if more school students came forward to contribute to research in the field.

He mentioned the importance of tapping the potential of the moon in meeting the energy needs of the country.

http://www.indiaedunews.net/Tamil_Nadu/ ... soon_7222/

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Re: Indian Space Program Discussion

Postby Rahul M » 21 Jan 2009 14:55

Yogi G wrote:ISRO has a million things to be proud of and a billion people are proud of it :)


that's a great line !

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Re: Indian Space Program Discussion

Postby symontk » 21 Jan 2009 16:32

The biggest problem with the current GSLV setup is that the SRB burns for a shorter time (107-109s) than the Vikas Engines (160 and now 140s), creating a dead weight of about 30 tons that has to be dragged along with the craft till Stage 1 burns out and falls off.

I have looked at other SRBs and I can see that they can be made to burn longer (130-140s) ex- Titan-4 SRBs. There are two solutions to this problem- either increase the fuel load by 25-30% (longer/fatter booster with more fuel segments) or a slower burning booster with less thrust but longer burn. Solution- Add one more segment to the S-139 motor (maybe 30 tons more propellant?) or a slower burning S-200 motor. Either way you get a longer burning booster, though the S200 modification is more trickier (fuel manufacturing process changes).


Your problem is the first bolded part and you see for yourself what you suggest as a solution in the second bolded part. As a solution for just dragging 30 tons for 30 seconds, you are designing a rocket which drags more weight for more time in your solution. ISRO knows that the solution for GSLV-2 is GSLV-3 and they are on right track.

If you are talking of replacing exisitng GSLV-2 with a similar rocket, the best would be to have a launch vehicle with S12*6, S200, L60 and C25 stages which will neatly solve the issue. You can also use the new semicryostage too instead of the liquid one.

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Re: Indian Space Program Discussion

Postby KrishG » 21 Jan 2009 18:49

symontk wrote:
The biggest problem with the current GSLV setup is that the SRB burns for a shorter time (107-109s) than the Vikas Engines (160 and now 140s), creating a dead weight of about 30 tons that has to be dragged along with the craft till Stage 1 burns out and falls off.

I have looked at other SRBs and I can see that they can be made to burn longer (130-140s) ex- Titan-4 SRBs. There are two solutions to this problem- either increase the fuel load by 25-30% (longer/fatter booster with more fuel segments) or a slower burning booster with less thrust but longer burn. Solution- Add one more segment to the S-139 motor (maybe 30 tons more propellant?) or a slower burning S-200 motor. Either way you get a longer burning booster, though the S200 modification is more trickier (fuel manufacturing process changes).


Your problem is the first bolded part and you see for yourself what you suggest as a solution in the second bolded part. As a solution for just dragging 30 tons for 30 seconds, you are designing a rocket which drags more weight for more time in your solution. ISRO knows that the solution for GSLV-2 is GSLV-3 and they are on right track.

If you are talking of replacing exisitng GSLV-2 with a similar rocket, the best would be to have a launch vehicle with S12*6, S200, L60 and C25 stages which will neatly solve the issue. You can also use the new semicryostage too instead of the liquid one.


I think he was talking about reducing the dead weight of solid stage by making up with extra thrust until the liquid strap-on boosters do their job.

I am still for a human-rated GSLV-Mk 2 with 2 stages with solid/UDMH strap-on boosters. A semi-cryo core and upper stage.

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Re: Indian Space Program Discussion

Postby ajay_ijn » 21 Jan 2009 18:56

Yogi_G wrote:
ss_roy wrote:An interesting youtube compilation of launch disasters. I have to say that India has done OK so far..

Maybe ISRO should play this clip whenever "english language media" critics question the engineering competence of indian scientists.

http://www.youtube.com/watch?v=wNsJUmFrUCA

ISRO could use a little more imagination, daring and mistakes, though..

Another video

http://www.youtube.com/watch?v=13qeX98tAS8

Chinese rocket disaster

http://www.youtube.com/watch?v=8_EnrVf9u8s

what GSLV-3 might look like

http://www.youtube.com/watch?v=4CviGrYuAhM

How a Titan 3 explosion looks like

http://s76.photobucket.com/albums/j17/TomcatFanatic123/Titan%2034D%20explosion%20pictures/



the easiest way would be to say that EVEN Israel launches their satellites on Indian rockets and that would immediately silence them. :lol:

Seriously, while Israel tries to stabilise the Shavit rocket ISRO has made great strides and left it far behind...ISRO has a million things to be proud of and a billion people are proud of it :)

Besides there are other countries like Taiwan, Korea, Brazil trying to come out with their SLVs but ISRO atleast 2 decades ahead of them.

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Re: Indian Space Program Discussion

Postby ss_roy » 22 Jan 2009 09:15

At the risk of reiterating..

The main reason behind my supported of further optimization of the GSLV-1/2 is very simple. You can create a much more reliable and cheaper version of the Long March-2 (LEO and GTO capacity) for a fraction of the price of building a new system, not to mention using parts and engines common with the GSLV-3.

Why not spend 15% more and get 2 new launchers.. instead of 1 new launcher? An upgraded GSLV could a heavier version of the Soyuz,launch heavier spy satellites and send fairly decent sized probes to planets from mercury to jupiter. The GSLV-3 could then be used to launch heavier stuff like big communication satellites, larger spacecraft/ pieces of space stations and probes to planets beyond jupiter.

You could also use the GSLV-3 to send people around the moon (in one shot) or send people to land on the moon (in two/three shots).. though I would prefer to see an indian version of the saturn-5.

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Re: Indian Space Program Discussion

Postby ss_roy » 22 Jan 2009 09:32

Ok here is another idea..

Some of you may know that the space shuttle as it exists today is quite different from the original concept. The original concept was a much smaller design without large main engines, that weighed about 11-20 tons. It had the a smaller crew (1-5) but landed like a glider. It was supposed to be launched on top a Titan-3 (which is rather similar to the GSLV-3) Ultimately USAF requirements killed that idea..

Why not follow that idea?

http://en.wikipedia.org/wiki/X-20_Dyna-Soar

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Re: Indian Space Program Discussion

Postby Nitesh » 22 Jan 2009 18:41


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Re: Indian Space Program Discussion

Postby KrishG » 22 Jan 2009 18:48

You could also use the GSLV-3 to send people around the moon (in one shot) or send people to land on the moon (in two/three shots).. though I would prefer to see an indian version of the saturn-5


I don't think the way Saturn- V/Ares-V went will be the right way for India. Those launch vehicles need soooooooooooooooooooooooo much of liquid hydrogen. Our main aim is to provide cheap access to space. I think our scientists will come out with a more intelligent way to send Indians on Moon.

ISRO has already started their research on earth-storable oxidizers which are more powerful then LOX and easy to store. Penta Fluro Chlorine and Tri-Fluro Chlorine (many times powerful than oxygen, reacts with almost everything to produce gaseous chloro-floro carbons)

The fact that Tri-Fluro Chlorine can harm earths atmosphere has stopped research in the field. Anyway why can't it be used on deep-space missions ????

Some of you may know that the space shuttle as it exists today is quite different from the original concept. The original concept was a much smaller design without large main engines, that weighed about 11-20 tons. It had the a smaller crew (1-5) but landed like a glider. It was supposed to be launched on top a Titan-3 (which is rather similar to the GSLV-3) Ultimately USAF requirements killed that idea..


The Russians are attempting a 14 ton space-plane in Kliper.

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Re: Indian Space Program Discussion

Postby Arun_S » 23 Jan 2009 11:07

ss_roy wrote:At the risk of reiterating..

The main reason behind my supported of further optimization of the GSLV-1/2 is very simple. You can create a much more reliable and cheaper version of the Long March-2 (LEO and GTO capacity) for a fraction of the price of building a new system, not to mention using parts and engines common with the GSLV-3.

Why not spend 15% more and get 2 new launchers.. instead of 1 new launcher? An upgraded GSLV could a heavier version of the Soyuz,launch heavier spy satellites and send fairly decent sized probes to planets from mercury to jupiter. The GSLV-3 could then be used to launch heavier stuff like big communication satellites, larger spacecraft/ pieces of space stations and probes to planets beyond jupiter.

You could also use the GSLV-3 to send people around the moon (in one shot) or send people to land on the moon (in two/three shots).. though I would prefer to see an indian version of the saturn-5.


ss_roy wrote:Arun,

I will post the detailed calculations later.

Where is the promised details? Till then I suggest no point floating ideas of a hybridized superior GSLV configuration. Let the numbers do the talking.

As an aside, I recall serious discussion with a middle school pal in KV at AF Station Lohgaon (his dad was aircrew), who wondered with disbelief as to why the Air Force can't simply fit Mig-21 engines on the Canberra. Later came to know he joined Indian Army.

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Re: Indian Space Program Discussion

Postby Shankar » 23 Jan 2009 13:28

don't think the way Saturn- V/Ares-V went will be the right way for India. Those launch vehicles need soooooooooooooooooooooooo much of liquid hydrogen. Our main aim is to provide cheap access to space. I think our scientists will come out with a more intelligent way to send Indians on Moon.

ISRO has already started their research on earth-storable oxidizers which are more powerful then LOX and easy to store. Penta Fluro Chlorine and Tri-Fluro Chlorine (many times powerful than oxygen, reacts with almost everything to produce gaseous chloro-floro carbons)

The fact that Tri-Fluro Chlorine can harm earths atmosphere has stopped research in the field. Anyway why can't it be used on deep-space missions ????


not a good analysis of the situation

when putting men in space the life support system becomes critical and consequently endurance of human being is long missions .The fastest way to go is often cheapest .In chandryan that problem was not there so a more time consuming route could be planned and executed

some of the on board lifesupport system that takes up lot of space and chunk of payload to orbit are liquid oxygen tanks,carbon di oxide scrubber,thermal insulation including personnel gear like space suits etc .

Fluorine lox combination ahs the highest specific impulse but very corrossive to handle so not used in present day space launch vehicles .Hydrogen is not expensive but adequate production infrastructure is still not there in India but coming up .With commercialisation of hydrogen fuel this will cease to be bottle neck

so forthe time GSLV is our best bet for deep space and manned missions

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Re: Indian Space Program Discussion

Postby Neilz » 23 Jan 2009 17:27

Hydrogen is not expensive but adequate production infrastructure is still not there in India but coming up .With commercialization of hydrogen fuel this will cease to be bottle neck

so for the time GSLV is our best bet for deep space and manned missions


:) Well there is a good news. It seams near Chennai there will be a H manufacture facility which proposed to have production rate of 80 tons per day.
This is unconfirmed in view of news report. I got this news from the head of GOVT agency. So chances are that it is true. Hope for the best keep finger cross.

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Re: Indian Space Program Discussion

Postby KrishG » 23 Jan 2009 20:59

Fluorine lox combination ahs the highest specific impulse but very corrossive to handle so not used in present day space launch vehicles


Yes! Tri-fluro Chlorine is highly corrosive therefore the use of Penta Fluro Chlorine has been suggested. It stays at an equillibrium with Tri-Fluro Chlorine and Fluorine and doesn't react with zinc and lead.

Till then I suggest no point floating ideas of a hybridized superior GSLV configuration. Let the numbers do the talking.


I think ss_roy is talking about the difference in burn time of the solid stage and the LSBs. Both are ignited together but the solid stage burns-out at 100 sec while it's empty fuel tank remains with the rocket until the LSBs burn out at 160 sec. So for the last 60 sec the weight of the empty solid stage fuel tank is just extra and the LSBs have to lift that also when there is no requirement.

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Re: Indian Space Program Discussion

Postby disha » 25 Jan 2009 00:16

A krish wrote:I think ss_roy is talking about the difference in burn time of the solid stage and the LSBs. Both are ignited together but the solid stage burns-out at 100 sec while it's empty fuel tank remains with the rocket until the LSBs burn out at 160 sec. So for the last 60 sec the weight of the empty solid stage fuel tank is just extra and the LSBs have to lift that also when there is no requirement.


Have you used rocksim or even built, launched and recovered a model rocket? The above assumption is completely wrong.

There is a max velocity at engine burnout and the booster is still coasting. It is imprudent to discard the booster at max velocity, one should discard that booster at max altitude!

Will post further, If I can get around to simplify the equations to be posted here. But note that sometimes the altitude reached in coast phase can be *twice* that of altitude during boost phase [or burn time!]

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Re: Indian Space Program Discussion

Postby disha » 25 Jan 2009 00:24

ss_roy wrote:Solids and hypergolics are the cheapest, unless you live in the USA (hypergolics and environmental laws) Proton, Titan-2, Titan-3/4, almost all Chinese launchers- excellent reliability.

RP-1/LOX is quite cheap and easy [Fuel, facility and engines]- Soyuz, Zenit, Delta 2, Atlas 5 Launcher

LH2/LOX is problematic because both fuels are cryogenic, but have different temperature/storage requirements. LH2/LOX engines are also tempermental.

Solids and hypergolic based launchers have the highest reliability.. bar none. A good RP-1/LOX launcher (soyuz) is also very good, but failures can be catastrophic. LH2/LOX as main stage engines are horrendously expensive and touchy.. (significant risk of failure and delays)

Overall-
Solids+Hypergolics are the cheapest and least likely to blow up.
If you have experience with them, RP-1/LOX are almost as good but blowups are like small nuclear weapons.

LH2/LOX are good on paper, but are best reserved for upper stages. Blowups are horrifying.


Wrong on several counts. It has its comparitive advantages and disadvantages. There are reasons one should not use RP-1/LOX and there are reasons one cannot use LH2/LOX and there are reasons one uses Solids + Hypergolics.

If the use case requires for example restartable engines, RP-1/LOX has some very hard engineering challenges to overcome which are not even present in the LH2/LOX engines! If LH2/LOX are good on paper, why is Space Shuttle using it? And why did ISRO spend 2 decades developing that technology?

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Re: Indian Space Program Discussion

Postby ss_roy » 25 Jan 2009 05:52

There are many things I could say about this particular reply, use your imagination..

Hypergolics have the advantage of reliability and storability along with a fairly decent mass fraction. It's fuels do not ignite in the air like H2 and RP-1. There is a reason that Russia and the USA developed ICBMs with hypergolics (before better solid fuels were developed). There is a reason that the Viking engines in Ariane-4 had less than 5 malfunctions (1-2?) in over 1,000 engine burns. Hypergolics are the only storable fuels that allow you to launch large spacecraft from the ground (CZ-2, CZ-3 family, Proton) without additional types of fuels/boosters.

Solid fueled rockets are incredibly reliable and mechanically simpler, though they have a poorer mass fraction. But they make excellent Stage 0 and Stage 1's (Ariane 5, Space shuttle).

RP-1/LOX are problematic to master, but once you master them- the reliability is very good! (Soyuz, Zenit, Delta-2 launchers)

H2/LOX are theoretically desirable, but not cost-effective in lower stages. The reason that Ariane-5, Delta-4 and the Space shuttle use them boils down to decisions of politics and organizational stances, not cost! Delta-4 and the Space Shuttle are the most expensive vehicles for launching stuff to LEO (over 10,000 $/ kg). Ariane-5 is subsidized and uses a much more simpler (and elegant) rocket engine design than either the Space shuttle or Delta-4.

If you have mature technology- Pure Hypergolics, Hypergolics + Solids and RP-1 are roughly comparable in cost and effectiveness. RP-1/ LOX can give you a better 'bang for the buck' with very heavy launchers. Do remember that I am talking about using cryogenic H2/LOX engines in the last stage for every case.

Wrong on several counts. It has its comparitive advantages and disadvantages. There are reasons one should not use RP-1/LOX and there are reasons one cannot use LH2/LOX and there are reasons one uses Solids + Hypergolics.

If the use case requires for example restartable engines, RP-1/LOX has some very hard engineering challenges to overcome which are not even present in the LH2/LOX engines!


Because Indians lack self-confidence and do not like to think critically (especially when following the white man blindly will get them promotions).

ISRO spent 2 decades developing the technology because they did not buy french cryogenic engines + technology when they could have (political interference + management attitudes). Even worse, they did not put enough resources and people towards developing them after 1993 (management). ISRO is an organization with competent people run by poor managers under a brain-dead central government/ bureaucracy (just like post 1972 NASA)

If the use case requires for example restartable engines, RP-1/LOX has some very hard engineering challenges to overcome which are not even present in the LH2/LOX engines! If LH2/LOX are good on paper, why is Space Shuttle using it? And why did ISRO spend 2 decades developing that technology?


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