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#220 by IslandPlaya on 21 Aug, 2014 21:47
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Forgive me. In modern terminology cryogenic engines use LH2 & LOX do they not? The definition is due to LH2 being a *deep* cryogen. Am I wrong?SpaceX don't use cryogenic engines. If by cryogenic you mean the use of LH2.
LOX is cryogenic. -
#221 by sanman on 22 Aug, 2014 01:50
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I thought rockets which use LOX and a non-cryo fuel are called "semi-cryogenic" -- at least that's how ISRO refers to it.
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#222 by RonM on 22 Aug, 2014 01:55
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Forgive me. In modern terminology cryogenic engines use LH2 & LOX do they not? The definition is due to LH2 being a *deep* cryogen. Am I wrong?SpaceX don't use cryogenic engines. If by cryogenic you mean the use of LH2.
LOX is cryogenic.
AFAIK, a cryogenic rocket engine is one that has either cryogenic fuel or oxidizer, or both. For a liquid to considered cryogenic it has to be below -150 C. LOX easily qualifies.
Outside of ISRO, I haven't seen the term semi-cryogenic.
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#223 by antriksh on 22 Aug, 2014 02:25
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If I am not wrong, LVM3-X mission was brain child of Dr. Radhakrishnan and he got it approved from government. Before there was no plan of any experimental mission. Also, Initial plan did not involve testing any crew module, but it was added later and this has made the mission very complex and challenging. It is no more a single mission , rather a combination of two experimental missions.
First mission involves launch of an experimental rocket and second mission involves reentry and recovery of a crew module (similar to SRE). This will require lots of planning, human resource and ISTRAC resources. ISRO will have to work with coast guard to use their ship for the recovery mission.
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#224 by Steven Pietrobon on 22 Aug, 2014 05:30
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Where did the November 1-8 launch date come from?
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#225 by input~2 on 22 Aug, 2014 11:14
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Where did the November 1-8 launch date come from?
From here -
#226 by AJA on 30 Aug, 2014 19:58
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This is a bit hard to digest. The two missions are quite independent of each other.
Certainly surprising that they'd tie it in with Mangalyaan. The general approach to find out what's happening is to follow the money. But looking at the breakdown of the budget (it was passed, with an eye-wash of a "debate", alongwith budgets for so many other departments at the same time) for this year doesn't help me much.
...
I think they should openly admit about the challenges that they face here which are responsible for postponement.
For the Mk-III - the capex is way down, and revenue expenditure has gone WAY up. This is usually supposed to happen after you deem your launch system has matured a little bit, and you start using it for commercial purposes. The Mk-III is certainly not ready! Hell.. the Mk-II isn't ready.
But there's another catch! ALL GSLV operational expenditure is under a different heading(!), which is itself divided into a very small capex and a large revex(!!) share and has seen a small (relative) increase in both. The SCRE budget (revex only) also increased 5x, and manned spaceflight's revex was increased, while its capex (minute to begin with) was decreased. (In this last case - last year's capex might've been something like land acquisition. They're not really building hardware yet). CUSP funding has stayed the same, but there's a new ISRO propulsion complex (for the cryogens I think) in the demand for grants which wasn't there last year. Semi-cryo spending is also up. They're also building a new trisonic wind tunnel.
Now, ISRO might be using the established, existing facilities for these new programs too - and that might allow project realisation with lower capex... but I'm not convinced. Don't know what's happening.
Mangalyaan's budget has seen a decrease (as expected). But it has still been sanctioned 65 crore rupees for capex... which is surprising. I can only think ISRO (ISTRAC) are expanding the I-DSN.
TL;DR - So yeah, while they're probably definitely facing challenges they didn't expect to - and while that has some part to play in the delay... might they also be waiting for the outcome of the Manglayaan's MOI, and maybe use that to either appropriate more money (to facilitate a slightly changed test) etc.?
Btw, --- isn't isolated in his criticism of the current ISRO leadership. I've been hearing it, both first, and second hand from people in the Indian scientific establishment - both ISRO and non ISRO for quite sometime now. -
#227 by vyoma on 01 Sep, 2014 09:03
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http://www.newindianexpress.com/states/kerala/Test-Flight-of-ISROs-GSLV-Mk-III-Deferred/2014/09/01/article2408518.eceQuote
ISRO is now planning to test-fly the GSLV Mk-III from Sriharikota only by October end at the earliest, sources said.
The reason for the delay is that the prototype of a two-man crew module for future manned space missions which is to be tested aboard the GSLV Mk-III, is not ready yet. Secondly, in the next few weeks, all ISRO activity will be centred around the `450-crore Mars Orbiter Mission (MOM), whose tryst with the Red Planet is slated for September 24.
Work on an upgraded cryogenic stage - which would remain ‘passive’ in this test mission - is also over, M Chandra Dathan, director, Vikram Sarabhai Space Centre (VSSC), said. ‘’The crew module prototype was included in the plans only a year ago. Its work is nearing completion,’’ he said. -
#228 by hornbill2007 on 03 Sep, 2014 19:42
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so it will be more wait for gslv mk3. hope things work out before the year is out.
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#229 by seshagirib on 04 Sep, 2014 09:55
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http://www.newindianexpress.com/states/kerala/Test-Flight-of-ISROs-GSLV-Mk-III-Deferred/2014/09/01/article2408518.ece
QuoteISRO is now planning to test-fly the GSLV Mk-III from Sriharikota only by October end at the earliest, sources said.
The reason for the delay is that the prototype of a two-man crew module for future manned space missions which is to be tested aboard the GSLV Mk-III, is not ready yet. Secondly, in the next few weeks, all ISRO activity will be centred around the `450-crore Mars Orbiter Mission (MOM), whose tryst with the Red Planet is slated for September 24.
Work on an upgraded cryogenic stage - which would remain ‘passive’ in this test mission - is also over, M Chandra Dathan, director, Vikram Sarabhai Space Centre (VSSC), said. ‘’The crew module prototype was included in the plans only a year ago. Its work is nearing completion,’’ he said.
Why do they need a complete cryogenic engine/stage if it is going to be passive? I was thinking, only a mass simulation is required, along with liquid oxygen and hydrogen tanks to simulate the sloshing if any. Using a actual cryogenic engine for this seem like an unnecessarily expensive option. -
#230 by AJA on 04 Sep, 2014 17:18
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Why do they need a complete cryogenic engine/stage if it is going to be passive? I was thinking, only a mass simulation is required, along with liquid oxygen and hydrogen tanks to simulate the sloshing if any. Using a actual cryogenic engine for this seem like an unnecessarily expensive option.
Been discussed in this thread before. It's a passive STAGE with mass-simulator instead of the engine. -
#231 by seshagirib on 06 Sep, 2014 05:58
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Why do they need a complete cryogenic engine/stage if it is going to be passive? I was thinking, only a mass simulation is required, along with liquid oxygen and hydrogen tanks to simulate the sloshing if any. Using a actual cryogenic engine for this seem like an unnecessarily expensive option.
Been discussed in this thread before. It's a passive STAGE with mass-simulator instead of the engine.
However the wording:
quote author=vyoma link=topic=15187.msg1249820#msg1249820 date=1409562222]
http://www.newindianexpress.com/states/kerala/Test-Flight-of-ISROs-GSLV-Mk-III-Deferred/2014/09/01/article2408518.eceQuote----
[/quote]
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Work on an upgraded cryogenic stage - which would remain ‘passive’ in this test mission - is also over, M Chandra Dathan, director, Vikram Sarabhai Space Centre (VSSC), said. ‘’The crew module prototype was included in the plans only a year ago. Its work is nearing completion,’’ he said.
( bold letters mine)
indicates that a real stage or a prototype will be flown but not fired. Maybe they want to have sensors/cameras on the stage to see how it will handle the launch stresses like vibration and G-forces. -
#232 by worldtimedate on 09 Sep, 2014 07:08
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I knew that the postponement would happen. Because in the past, ISRO failed to keep up the launch schedule. I am even skeptic whether the launch would take place in this year. Lets take a look at the statements made by ISRO recently regarding GSLV MKIII Mission. The launch time line is getting delayed one after another.
GSLV Mark III ready for mission
http://www.thehindu.com/news/gslv-mark-iii-ready-for-mission/article5845204.ece
GSLV to soar into sky with crew capsule in June
http://www.thehindu.com/sci-tech/science/gslv-to-soar-into-sky-with-crew-capsule-in-june/article5873835.ece?ref=relatedNews
Isro postpones GSLV-MKIII flight scheduled in August
http://timesofindia.indiatimes.com/Home/Science/Isro-postpones-GSLV-MKIII-flight-scheduled-in-August/articleshow/40515679.cmsQuote
The GSLV-MKIII experimental flight was to also test the crew module structure of HSP. Stating that Isro aims at completing the the mission within this calendar year, the scientist said the crew module structure is in advance stage of realisation for the same.
Test Flight of ISRO's GSLV Mk-III Deferred
http://www.newindianexpress.com/states/kerala/Test-Flight-of-ISROs-GSLV-Mk-III-Deferred/2014/09/01/article2408518.eceQuote
Originally planned for April this year, the GSLV Mk-III test-flight had been postponed to June end. Work on an upgraded cryogenic stage - which would remain ‘passive’ in this test mission - is also over, M Chandra Dathan, director, Vikram Sarabhai Space Centre (VSSC), said. ‘’The crew module prototype was included in the plans only a year ago. Its work is nearing completion,’’ he said. As per the present schedule, a PSLV mission is next in line - in the first or second week of October - after the Mars mission docks with the Red Planet.
So, it is now clear that the crew module has not been ready. But why had ISRO announced the launch of GSLV MKIII when they were uncertain about the time when the crew module would be ready.
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#233 by vineethgk on 10 Sep, 2014 17:45
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GSLV Mark III ready for mission
http://www.thehindu.com/news/gslv-mark-iii-ready-for-mission/article5845204.ece
GSLV to soar into sky with crew capsule in June
http://www.thehindu.com/sci-tech/science/gslv-to-soar-into-sky-with-crew-capsule-in-june/article5873835.ece?ref=relatedNews
Isro postpones GSLV-MKIII flight scheduled in August
http://timesofindia.indiatimes.com/Home/Science/Isro-postpones-GSLV-MKIII-flight-scheduled-in-August/articleshow/40515679.cms
Test Flight of ISRO's GSLV Mk-III Deferred
http://www.newindianexpress.com/states/kerala/Test-Flight-of-ISROs-GSLV-Mk-III-Deferred/2014/09/01/article2408518.ece
You missed the following two links in the list. I guess that's where it should start..
http://www.frontline.in/static/html/fl2016/stories/20030815006111200.htmQuoteThe Union government has approved the project and the three-stage rocket will lift off in 2008.
http://www.frontline.in/navigation/?type=static&page=flonnet&rdurl=fl2217/stories/20050826002409200.htmQuoteTHE first flight of the Geo-synchronous Satellite Launch Vehicle (GSLV)-Mark III is expected to take place by the end of 2007.
And this was in articles that appeared in 2003 and 2005! Not sure if this was a case of misreporting, as The Hindu and Frontline were usually more reliable than other Indian media on these stuff. After all, anyone with even the least idea of the complexities of launch vehicle development would have known that 2007-2008 timeframe as mentioned for the launch of this all-new rocket design would be plain unrealistic. But if it wasn't a case of misreporting, what was it? Just a plain instance of gross underestimation and over-confidence on the part of ISRO? Or an intentional tactic to get funds allocated from the Govt in advance so that project does not get delayed due to want of funds? This is not in any way to criticize ISRO or to belittle its achievements. For an Indian governmental organization with all its assorted inefficiencies and bureaucratic red tape, ISRO has been doing extremely well. But I do feel many times that it would have been better if ISRO had taken care to give more realistic (read pessimistic) estimates like "the rocket would be launched sometime in the 2015-2018 timeframe" etc...
Anyways, here's hoping for a successful test flight before the end of this year
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#234 by AJA on 11 Sep, 2014 02:41
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Just a plain instance of gross underestimation and over-confidence on the part of ISRO? Or an intentional tactic to get funds allocated from the Govt in advance so that project does not get delayed due to want of funds?
Any developmental program is going to be plagued by schedule and cost uncertainties. That's a consequence of operating at the edge of your knowledge, knowhow and experience base... and pushing that envelope. Of course, at the end of the day, you want a number, and the people at the helm get paid money for making these guesses, and get paid the big money for the accuracy of those guesses. In such cases, a responsible critic should resort to citing over-confidence and/or underestimation of complexities as proximal causes for delays only if these you can demonstrably show that the people in charge deviated from their own standards of guesswork they'd previously demonstrated. All circumstances are never going to be the same, certainly not technically - so you look at the calls and allowances they made for relatively constant things. e.g. in the learning curve expected from your technicians, in defining project specific administration procedures, and whether they were truly analogous, in ethos, to similar procedures in past projects etc.
More specifically though - remember that this is still the Mk-III. ISRO expected to have the Mk-II operational and running far earlier than they did. The problems with that rocket would've tied up the staff, as well as facilities, and these delays no doubt spilled over into the Mk-III. Not to mention the unexpected Devas fiasco. Again, you could say that a good organisation would comprise divisions where there would be a free flow of information and collaboration, but whose divisions would be insulated for external impedance.
Secondly, the longer something spends on the drawing board, the more extensive it tends to get. Well intentioned, and dedicated people whose bits of the project are not on the critical path, find some free time to think up more things to test, and start tacking things on, because "it's delayed anyway"; and "this would make the delay worthwhile". Before too long, you've ended up changing the project specification, and these additions interfere with one another, and you're in a mess. A fair amount of this probably happened
Btw, ISRO hasn't been funding limited for a while now. They've been getting whatever they asked for. However, you could argue that in this case, they should keep asking for more, until the government says no - that they can always devote more resources to whatever it is that's constraining them - whether it's staff, or infrastructure etc. - until they do become funding limited. -
#235 by abhishek on 21 Sep, 2014 17:38
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Quote
They told me that I would be looking for an R&D organisation after my master's degree," says Gupta. "So why not join ISRO and let them sponsor your master's course?" Now, Gupta works on the next generation Geostationary Launch Vehicle (GSLV), the heavy lifter that ISRO is developing for launch next year, and sits in its design review committee.
http://economictimes.indiatimes.com/articleshow/42749182.cms?utm_source=contentofinterest&utm_medium=text&utm_campaign=cppst
GSLV MK3 launch once again postponed ?
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#236 by input~2 on 22 Sep, 2014 15:56
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Sounds like itQuoteThey told me that I would be looking for an R&D organisation after my master's degree," says Gupta. "So why not join ISRO and let them sponsor your master's course?" Now, Gupta works on the next generation Geostationary Launch Vehicle (GSLV), the heavy lifter that ISRO is developing for launch next year, and sits in its design review committee.
http://economictimes.indiatimes.com/articleshow/42749182.cms?utm_source=contentofinterest&utm_medium=text&utm_campaign=cppst
GSLV MK3 launch once again postponed ? 
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#237 by vineethgk on 23 Sep, 2014 06:27
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Are the lower stages of the launcher already stacked in VAB? If so, and assuming the launch is indeed postponed to next year, are they likely to destack it to make the VAB available for IRNSS-1D launch later this year?
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#238 by johnxx9 on 24 Sep, 2014 12:28
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What next for Isro?Quote
“The launch of Mark-III would be after the PSLV C26 launch. It could be late October or November, based on the weather conditions,” he said.
Before Mark-III, Isro is planning to launch PSLV C26, with IRNSS 1B satellite, which will be the third navigation satellite. It may be noted, first one in the series was launched in July, followed by the second in April.
“Third one will be in the first half October. Operations are going at the moment, spacecraft is at Sriharikotta, vehicle assembly has already started,” said Radhakrishnan, adding that by December fourth navigation satellite will also be launched. -
#239 by vineethgk on 24 Sep, 2014 14:59
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Great. So it seems the test flight isn't delayed as yet, though it might.Quote
“Full engine has been assembled now, we are going to start the ground testing of the engine in few months now. This engine will have a thrust level of nearly 20 tonne as compared to 7.5 tonne of the GSLV we flew in January 2014,” he said.
QuoteRadhakrishnan said that the ground test for the cryogenic engine is currently underway at Mahendragiri.
The statements looks kind of self-contradictory. Maybe it was problem with the reporting. But anyways its good to hear that the CE-20 is inching closer to reality. Haven't been hearing much about it for some time.
