GSLV Mark II

arnabmit

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Ice, frost, tubes, cables.
Please explain how and why would ice form in between T=0 and T=+10sec on a day when ambient temperature was about 20°C. Is it because of the cryo fuel? But wouldn't that imply that the stage is not properly insulated?

This question has bugged me forever, what are the things which fall down at launch? Something similar (foam block?) fell and crashed in the shuttle wing which resulted in loss of structural integrity during reentry of Space Shuttle Columbia and eventual burn up leading to the death of Kalpana Chawla and others.
 

venkat

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yea HAL awesome paint job if you had half the dedication of ISRO scientists would you have hmmmm well pointless anyway
what better understanding of HAL you have ? Because you are an average!!! Go and have a look at HAL AEROSPACE division. If it is successful the credit is taken by them and failures are attributed to HAL!! At least Mr. Chandra Dathan, PD,LPSC is sensible enough in his speech to acknowledge the contributions of all organizations and institutions involved !!
 

Twinblade

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Please explain how and why would ice form in between T=0 and T=+10sec on a day when ambient temperature was about 20°C. Is it because of the cryo fuel? But wouldn't that imply that the stage is not properly insulated?
The tanks are insulated to a reasonable degree within weight constraints. You are talking temperatures 200 degrees below freezing in a very humid tropical climate. The conductivity of the tanks is tiny but the temperature gradient is massive, hence the outside temperature of the tanks is several degrees below freezing. The foam block on the space shuttle was different, it was not supposed to fall.
 

AVERAGE INDIAN

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what better understanding of HAL you have ? Because you are an average!!! Go and have a look at HAL AEROSPACE division. If it is successful the credit is taken by them and failures are attributed to HAL!! At least Mr. Chandra Dathan, PD,LPSC is sensible enough in his speech to acknowledge the contributions of all organizations and institutions involved !!
i dont have to i dont have any good opinion of HAL end of discussion
 
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The Messiah

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one of our "friends" denies us technology and the other actually gives

we should know who's who
and the one who denies us also puts pressure on the one sharing not to share in return for something. we all know who is who :thumb:
 

The Messiah

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I didn't even know about this..usually i watch it live on tv :scared2:

congratulations to isro :salute:
 

LalTopi

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Thanks for your welcome and reply.
Being a new member, I don't have privileges like pasting link etc. That is why mentioned the Chinese SLV model and wiki site - so that one can look into it. I also request moderators to transfer my post into new thread, if they prefer it.
Nonethless - following is info from wiki:

Long March 3B/E
The Long March 3B/E is an enhanced variant of the Long March 3B, featuring an enlarged first stage and boosters, increasing its GTO payload capacity to 5,500 kilograms (12,000 lb).Its maiden flight took place on 13 May 2007, when it successfully launched Nigeria's NigComSat-1, the first African geosynchronous communications satellite

Mass 458,970 kilograms (1,011,900 lb)
Stages 3
Payload to GTO 5,500 kilograms (12,000 lb)
Total launches 15
Successes 3B/E: 15
First flight 3B/E: 13 May 2007

Boosters (Stage 0)
No boosters 4
Thrust 740.4×4 KN
Specific impulse (2556.2 N-s/kg)
Fuel N2O4/UDMH

First Stage
Thrust 2961.6 KN
Specific impulse (2556.2 N-s/kg)
Fuel N2O4/UDMH

Second Stage
Thrust 742 KN (Main)
11.8×4 KN (Vernier)
Specific impulse 2922.57 N-s/kg (Main)
2910.5 N-s/kg (Vernier)
Fuel N2O4/UDMH

Third Stage
Thrust 78.5×2 KN
Specific impulse (4312 N-s/kg)
Fuel LOX/LH2


GSLV-III
Mass 630,000 Kg
Stages 3
Payload to GTO 4,000–5000 kg
A post in DFI in the thread related to unified launch system mentioned weight of 700t for 5t satellites.
Your original question was why is the planned GSLV so much more heavier than the Chinese rocket for the same payload capability.

If you look at the Chinese spec you supplied you will note that their rocket uses liquid propellants for both the first and second stage with a cryogenic third stage. whereas ISRO has opted for a solid propellant first stage of 2*200 ton S-200 strap on boosters. Solid boosters are much heavier but also have certain advantages and are also used in other rockets e.g. Ariane 5 and the original Saturn 5 for the lunar landings. The S-200s make up about two thirds of the weight of GSLV iii.

see the mark 3 thread for more information on the S-200: http://defenceforumindia.com/forum/strategic-forces/50020-gslv-mark-iii.html

see also wiki link which discusses some of the reasons for sing solid boosters: Solid-fuel rocket - Wikipedia, the free encyclopedia

hope this helps.
 

LalTopi

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That's why I say, America can never be our friend like the Russians are. Our Government is the biggest idiotic Government in the world to be aligning with the Americans to check the rise of China.
To quote Charles DeGualle, 'no nation has friends, only interests'
right now our interests with the US are C130, P8i, Globemaster, Apache etc.
and of course Mrs DK - like I said not friends but interests.
 

Free Karma

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cobra commando

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ISRO completes second orbit raising manoeuvre of GSAT-14

BANGALORE: The second orbit raising operation of an advanced Indian communications satellite launched by a rocket using an indigenous powerful booster technology from the space port of Sriharikota was today successfully completed by ISRO scientists. The Indian Space Research Organisation (ISRO) said the Apogee Motor of GSAT-14 was fired for 2,629 seconds with a realised orbit of 32,160 km Perigee, nearest point to earth, by 35,745 km Apogee, farthest point to earth. The third orbit raising operation is planned on January 9 to place the two-tonne satellite in geostationary orbit, ISRO said in a statement here. The successful flight test of the indigenous cryogenic upper stage on the satellite has propelled India into the exclusive club of the US, Russia, France, Japan and China, which have mastered the complex cryogenic engine technology. The satellite was put into orbit by GSLV-D5 after a textbook launch on Sunday from the spaceport in Andhra Pradesh. India has for years been trying to develop its own cryogenic rocket engines that are designed to put heavier satellites into high geostationary orbits, about 36,000 km from Earth. The powerful booster technology uses super-cooled liquid fuel--a mix of oxygen and hydrogen in liquid form and kept at a very low temperature.

ISRO completes second orbit raising manoeuvre of GSAT-14 - The Economic Times
 

praneetbajpaie

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OK, so the GSLV Mk 1 used the Russian engines

GSLV Mk 2 used the indegenous engines

and GSLV Mk 3 will use the indigenous engines

Is the the correct surmise? and what are the CE 7.5 and CE 20 engines?

Are they variants of the Vikas engine or completely different?

BTW, can't wait for the GLSV Mk 3 launch in APril, 2014
 

From Realm of D&T

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Congratulations ISRO and India.

Watched Live with my son and wife.

Great day for India nation.

The director said 'we have paid the debt back to this nation'. Yes you have Sir, now the it for all the present and future generations to carry this baton and achieve more and more mile stones in space science without halt.
I too

The all mission was successful within minutes.
 

rahulrds1

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Very informative. Must read:We are three ISRO scientists here to answer your questions -AMA : india
We are three ISRO scientists here to answer your questions -AMA : india
Few important contents from the same link

Q]GSLV Mk III is equivalent to the Chinese Long March 3 and its variants. Whats the time frame for a Long March 5 equivalent(14T GTO) and what will it be called or is called?

[Ans:]No plans as of now. MkIII is more advanced than Long march 3.

Q]Are Indian spy satellites covered under the ISRO-space budget or under the Defense budget

[Ans:]No idea :D

Q]Does India have a Anti-Satellite capability and if its kept under wrap due to bad global PR reasons, whats the shortest span of time, India can retrofit a solution( an efficient jugaad of sorts)

[Ans:]Maybe an emergency will tell, but it can be done.

Q] How correct is the statement that the 2 Indian Space Launch vehicles can be within 6-9 months be turned into a ICBM if its required?

[Ans:]We already have good ICBMs. Why convert good old PSLV. PS: Tech is same everywhere. Go figure.

I ask as some people question the feasibility of this whereas I was also told or read even a decade back that India is not making a ICBM to avoid sanctions but it has the tech.

Again, Agni 5

Q]The Cryogenics technology took India so long to master because of the US-Soviet/Russian bilateral agreement and its implication on selling of tech to India. How is US seen in this regard since its the stumbling block for Technology transfer to India.

[Ans:]International geopolitical dynamics define such decisions.

Q]What other Advanced Technologies is still off the market for India and what portion of those concern ISRO and Indian space development.

[Ans:]After cryo, nothing very important remains. We can manage. We have got a great Semi-Cryo project going on, which would be even more awesome than cryo.

Q]What was the Indian position in the 1990's on the ISS. The US and the West intentionally kept China out citing security concerns. Why was India not involved and whats the probability India will get invoved now given that the ISS will only be up till 2020.

Sorry, I have no idea. I doubt India would join the program now.

Q]Few years back the US passed a Law which bars foreign nationals (students and Scientists from entering certain NASA enclosures) Has this(if at all) affected ISRO and the Indian Space development.

[Ans:]Nope. Even we don't allow foreigners in lots of our places :D

Q]ISRO mission to Venus in 2015. Whats new about it, what is going to be tested and surveyed.

[Ans:]No-one is going to Venus in 2015. Where did you hear about this?

Q]How are GAGAN and IRNSS different, this seems to be confusing me.

[Ans:]Google. Also, read other answer posted somewhere here.

Q]Why is IRNSS only limited to the Indian subcontinent Only, Why isn't it Global like the new Chinese BeiDou-2 system. Surely the sale of service like GPS does and BeiDou-2 and EU's Galileo will provide is enough incentive plus much more.

[Ans:]No, sales will not be that much. Read on the glonass conflict in usa that was in current affairs recently. For our purpose, Indian subcontinent will do.

Since its been mentioned that all ground hardware and receivers will be India made how will this be integrated into Mobile and such devices since such chips are manufactured at few places(near assembly plants).

Development is in progress.

Q] How long before we can use it in our phones?

[Ans:]It will take some time. Cannot comment on timeframe.

Q]How will the accuracy be, is using a geostationary orbit for GPS system efficient(i've read that such satellites provide limited coverage to only where the satellites are visible)

[Ans:]Accuracy will be good, comparable to other systems in use now.

Q] Lastly, all the best and keep doing your great work. Indians 200-300 years from now will thank you guys even more than you get now.

[Ans:]You are welcome. Spread the word about ISRO's activities among your friends and relatives.


We are three ISRO scientists here to answer your questions -AMA : india
 
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