Indian Space Programme Discussion

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Re: Indian Space Programme Discussion

Post by AbhiJ »

Isro to launch Astrosat to study the skies
Astrosat will be launched aboard a PSLV in 2015, will have six instruments and can be described as a multi wave length observatory in space.
Landing Spot for Chandrayaan 2 Identified
Chandrayaan-2 is an advanced version of Chandrayaan-1, and it aims to demonstrate Isro's capability to soft-land on the lunar surface. Minister of state for PMO V Narayanaswamy recently announced in the Parliament that the mission, which is likely to take place in 2016-17, is progressing well with Isro having identified landing spots on the lunar surface.
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Re: Indian Space Programme Discussion

Post by member_28108 »

http://articles.economictimes.indiatime ... a-irnss-1b

Experimental launch of GSLV Mark III in May/June: ISRO
PTI Feb 23, 2014, 09.44PM IST


Tags:
Satellite|Mark III|launch|ISRO|GSLV|Experimental|Chairman


PUDUCHERRY: Indian Space Research Organisation would carry out an experimental launch of GSLV Mark III in May end or June beginning, its Chairman K Radhakrishnan said here today.

The national space agency is also set to send its next satellite IRNSS-1B on board rocket PSLV C24 from Satish Dhawan Space Centre at Sriharikota in the last week of March or in the first week of April, he told reporters on the sidelines of a function here.
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Re: Indian Space Programme Discussion

Post by Varoon Shekhar »

^
Nitpicking, but once again, we have inaccurate launch dates. ISRO said the GSLV Mark 3 test would be in April, now they are shifting it to May-June. The IRNSS-1B was originally set for Feb end, early March, now it is late March or April.

Astrosat is way off. It was supposed to be launched sometime in 2014, it's pushed back to 2015!

And what of SRE-2? Hope that's not also in 2015, because just in December, the Hindu newspaper mentioned an April mission date!
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Re: Indian Space Programme Discussion

Post by Bade »

I used to think Astrosat launch delay is due to launcher scheduling priorities, it slipped by almost 5 years but there were payload related issues which have been solved now.
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Re: Indian Space Programme Discussion

Post by Sridhar »

Is it possible that the Hindu article confused the orbital vehicle launch that is part of the LVM3-X1 mission in April with the SRE-2? I don't remember seeing any official reference (i.e. ISRO statements or attributable comments from ISRO officials) giving dates for SRE-2.
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Re: Indian Space Programme Discussion

Post by Sridhar »

If you are referring to the following article in the Hindu, it is ambiguous. It just refers to a space capsule which the orbital vehicle prototype is. That is part of the GSLV-M3 experimental mission in April (since rescheduled to May/June).

http://www.thehindu.com/sci-tech/scienc ... 484393.ece
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Re: Indian Space Programme Discussion

Post by merlin »

Yeah I think SRE-2 will be much later since the structural model of the orbital vehicle is what is more important for HSP. SRE-1 would have already validated some key technologies/procedures.
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Re: Indian Space Programme Discussion

Post by Sridhar »

More details on what is planned wih the cree module in this uocoming LVM3-X1 mission.

http://timesofindia.indiatimes.com/home ... 016566.cms
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Re: Indian Space Programme Discussion

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Re: Indian Space Programme Discussion

Post by UlanBatori »

First good article I have seen from Sobha Warrier. May be breathing good Malloostani air for the first time in ages.

BTW, the "Shreekumar" mentioned there is in a class all by himself. In Pakiness, that is..
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Re: Indian Space Programme Discussion

Post by Sridhar »

Cross posting (with permission from the original contributor) from another forum.

Image

The first photo of the ISRO space suit. Click through for a larger image.

Source: ISRO (not in the public domain as of now)
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Re: Indian Space Programme Discussion

Post by vdutta »

^^ this and other pics of this suit are in public domain for over a year.
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Re: Indian Space Programme Discussion

Post by vdutta »

Last edited by Gerard on 03 Mar 2014 17:43, edited 1 time in total.
Reason: Removed inlining
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Re: Indian Space Programme Discussion

Post by vdutta »

Last edited by Gerard on 03 Mar 2014 17:43, edited 1 time in total.
Reason: Removed inlining
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Re: Indian Space Programme Discussion

Post by Sridhar »

OK. Didn't know. I was just cross posting, as I said.

This is the photo of the engineering prototype. Don't know if the old photos are of the engineering prototype, but will check.
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Re: Indian Space Programme Discussion

Post by Brando »

There are many "types" of space suits. There are the non-pressure suits and the pressure suits like the "crew suit", the "intra-vehicle suit", the "launch/re-entry suit", the "moon suit", the "eva suit" and a couple of others. The Russians and Americans have a whole bunch of suits depending on what they are doing. This looks like it is a very very basic suit that is a mix between a "crew suit" and a "launch suit" something akin to what the early Mercury or Gemini probe suits or the Vostok era SK suits. The Chinese have a impressive suit as well in their Feitian suit which is said to be more sophisticated than the Russian Sokol and Orlan suits. If ISRO does send its own astronauts to space and plans on EVA, most likely they will buy a couple of Orlan-M suits to use instead of risking a new suit.

IMO, a space suit is inherently inefficient and impractical from the get go for EVA in space. Humans were just not built to operate out of a gravity well. The best and most practical approach ought to be using unmanned drones to perform EVA activities. They would be smaller, faster and easier to do the same job as spending 3 hours getting into a suit, struggling through an airlock, bumbling around in space awkwardly and then navigating back inside the vehicle and suffering decompression effects after taking off the suit. Not to mention the hundreds of hours of training for EVA on Earth. All in all, human EVA is ridiculously inefficient but its "glamorous" and that's why everybody spends so much time on it.
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Re: Indian Space Programme Discussion

Post by Sridhar »

I think as of now, there are no EVA plans in the ISRO human spaceflight program. (There aren't any concrete plans anyway, but whatever has been revealed envisages placing 2-3 humans in orbit and their safe return to earth with no mention of any EVA).
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Re: Indian Space Programme Discussion

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Re: Indian Space Programme Discussion

Post by anmol »

NASA to launch satellite in collaboration with ISRO
zeenews.india.com | Feb 26th 2014 1:31 AM
Washington: US space agency NASA today said it would launch a water-related satellite in collaboration with India's ISRO.

The NASA-Indian Space Research Organisation Synthetic Aperture Radar mission is a part of its plan to launch in the next seven years a series of satellite related to water and draught, the agency said.

Among others include the Ice, Cloud, and land Elevation Satellite-2 (ICESat-2); Gravity Recovery and Climate Experiment (GRACE) Follow-on and Surface Water Ocean Topography mission.

"These satellite missions join more than a dozen NASA airborne sensors focused on regional-scale issues, understanding detailed Earth science processes and calibrating and validating NASA satellites," the space agency said.

"NASA monitors Earth's vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing," it said.

"The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet," it said.

NASA said it is scheduled to launch three new Earth science missions this year, which will contribute to water cycle research and water-related national policy decisions.

The Global Precipitation Measurement (GPM) Core Observatory, a joint satellite project with the Japan Aerospace Exploration Agency scheduled for launch Thursday, February 27, will inaugurate an unprecedented international satellite constellation that will produce the first nearly global observations of rainfall and snowfall. The new information will help answer questions about our planet's life-sustaining water cycle, and improve water resource management and weather forecasting.
"ISS-RapidScat, scheduled to launch to the International Space Station (ISS) in June, will extend the data record of ocean winds around the globe. The data are a key factor in climate research, weather and marine forecasting and tracking of storms and hurricanes," NASA said.

"The Soil Moisture Active Passive (SMAP), launching in November, will inform water resource management decisions on water availability. SMAP data also will aid in predictions of plant growth and agricultural productivity, improve short-term weather forecasts and long-term climate change projections, and advance our ability to monitor droughts and predict floods and mitigate their related impacts on people's lives," the space agency said.
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Re: Indian Space Programme Discussion

Post by chackojoseph »

GSLV Mk-lll launch vehicle development cost increases

India today approved the revised cost estimates of Rs.2962.78 crore for completion of the development programme of Geo-synchronous Satellite Launch Vehicle (GSLV Mk-lll) and to carry out an experimental flight called LVM3-X. The additional fund requirement is Rs. 464.78 crore to complete the scope of the project including one experimental flight called LVM3-X and two developmental flights called GSLV Mk-lll D1 and GSLV Mk-lll D2.
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Re: Indian Space Programme Discussion

Post by arun »

PTI via Economic Times:
Government approves additional Rs 464.78 crore for GSLV Mark-III programme

NEW DELHI: Government today approved the revised allocation of Rs 2962.78 crore for completing the heavy-duty Geo-synchronous Satellite Launch Vehicle Mark-III programme and to carry out experimental flight LVM3-X.

The Union Cabinet approved the additional fund requirement of Rs 464.78 crore to complete the scope of the project including one experimental flight called LVM3-X to validate the critical atmospheric regime and two developmental flights called GSLV Mk-III D1 and GSLV Mk-I …………..............
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Re: Indian Space Programme Discussion

Post by ravar »

Any foreseeable threat to the SC engine tie-up of ISRO with Ukraine wrt to the regime change there?

As per WikiLeaks, Ukraine had sought US approval before entering into a contract with ISRO. It needs to be assumed that it received US blessings to go ahead. So, a pro-West regime in Ukraine might not change the essential nature of the contract, if at all there is a threat.

Also, the leaked wires indicated that there wouldn't be any transfer of 'know-why' and associated software for the SC engine. The contract envisages the transfer of drawings and help to assemble one prototype IIRC.

Hence, ~6 years into the tie-up, ISRO would have progressed much into the project to have any significant adverse impact even if Ukraine reneges on the contract.
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Re: Indian Space Programme Discussion

Post by Brando »

Putin has a 100,000 Russians and swarms of his buddies in Crimea ready to kick Ukraine in the shins if they dont swing his way at the end of the day. I don't think the Russians would mind carving up Ukraine if the "pro-EU" Western Ukraine become too aggressive despite assurance that they will respect Ukraine's territorial sovereignty - they said the same thing about Georgia and tore off a chunk without batting an eyelid. Neither Obama nor the EU have the wherewithal or the stones to play with Putin in his backyard.

As to the Semi-cryoengine, I think any semi-cryo engine that ISRO uses will be ultimately its own design. These "collaborations" and "contracts" are basically the foundation and technology research programs, just like the Cryogenic engine contracts that ISRO signed in the 80s and 90s. Ukraine is bound by the MTCR, so they can't export technologies that would contravene and the US is smart enough to tighten screws on one hand by getting Ukrainian companies banned while American companies like Mayers and Thiokol take those contracts from ISRO instead.

Code: Select all

http://www.wikileaks.org/plusd/cables/07KYIV2245_a.html

4. (C) In a conversation after the meeting, Varyanychko specified that the contract was for delivery of blueprints for the rocket engine that ISRO would use to build its own engine; Ukrainian companies simply did not have the capability actually to construct the engine themselves. He stressed that the information would allow ISRO to build only one model of engine and reiterated the point that Yuzhnoye would not provide any engineering or technical details on how the plans had been developed. Belokolos noted that, if Ukraine lost the contract, Russian companies would step in and warned that the U.S.-Ukraine relationship would be very negatively affected if the public and government officials were to learn that the U.S. had prevented the deal from going through. Varyanychko said the State Export Control Service had earlier authorized a license to negotiate the deal, but was now holding up the export license to fulfill the contract. He appealed for a speedy and positive U.S. response. 
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Re: Indian Space Programme Discussion

Post by vina »

Hmm. I wonder with this lil kerfuffle going on in Ukraine, what is the effect on ISRO's semi cryo Kerosene-Lox engine design that we were getting from Ukraine. If that engine is shot and contract beyond salvage, why not scrap that entire thing and do a Hanuman jump and go for a LCH4-LOX engine (more efficient) of indigenous design and ditch this kerosene business altogether ?
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Re: Indian Space Programme Discussion

Post by tushar_m »

How Isro got an indigenous cryogenic engine
New Delhi: Mission director K. Sivan kept his fingers firmly crossed in the mission control room at the Indian Space Research Organisation (Isro) Satish Dhawan Space Centre in Sriharikota on the morning of 5 January as the moment drew closer for the launch of the Geosynchronous Satellite Launch Vehicle, or GSLV-D5.

The rocket, powered by India’s indigenous cryogenic engine, had been tested and reviewed numerous times in the four months since its aborted launch on 19 August due to a crack in the fuel tank. After the 5 January launch, every step that the rocket cleared made Sivan a happier man. But he also became more anxious—after all, of the seven GSLV launches earlier, five had failed. It was only when the satellite GSAT-14 onboard the GSLV-D5 was inserted into a precise orbit that Sivan relaxed. “It was like the rebirth of GSLV,” he said.

The search for cryogenic engine
The GSLV programme was started by Isro in response to India’s mounting communications needs. By 1987, the government had approved the development of the second generation INSAT-2 series of satellites, weighing more than 2 tonnes. Isro wanted to develop a 2.5-tonne class of satellites and put them into a geostationary transfer orbit at 36,000km from Earth’s surface.

Isro also wanted to make a vehicle that would be bigger, lighter and more efficient than its workhorse Polar Satellite Launch Vehicle (PSLV). There were three fuels options: earth storable, semi-cryogenic, and cryogenic.

Cryogenic engines, which use liquid hydrogen and liquid oxygen as fuel and give the most thrust, are usually prepared for the “upper stages”—the last stage of the rocket—because this stage provides 50% of the velocity of 10.2km per second needed at the point of injection of a satellite. In 1986, at a cost of Rs.12 crore, Isro scientists began developing a one-tonne cryogenic engine to try and understand how to handle liquid hydrogen and liquid oxygen. At the same time, a design team was formed at Isro’s Liquid Propulsion Centre at Mahendragiri in Tamil Nadu to come up with the design of a seven-tonne turbo-fed engine. Although this development boosted the confidence of Isro engineers, Isro knew that it couldn’t wait much longer to develop the indigenous engine.

The Russian deal

It was then that Isro thought of procuring cryogenic engines from other countries. After rejecting offers from the US and France for both the sale of engines and transfer of technology, India approved an offer by the Soviet Union’s Glavkosmos space agency in 1990. India sent eight scientists to Moscow to work with Soviet scientists. They worked there for 15 months, but did not have access to everything.

“The Russians were very secretive about everything, even though they had signed the technology transfer agreement. Discussions were limited, and the Indian scientists were never allowed to walk the labs freely; they needed clearance to move around the lab,” said B.N. Suresh, former director, Vikram Sarabhai Space Centre in Thiruvananthapuram. “Hence they couldn’t learn very much.”

Then, 15 months after the deal was signed, the US raised objections citing a violation of the international Missile Technology Control Regime (MTCR). The West feared that cryogenic technology could be used by India to develop intercontinental ballistic missiles, which is rejected by Indian scientists.

Eventually, in 1993, Glavkosmos backed out of the deal and revoked the transfer of cryotechnology agreement. Under a renegotiated deal, Russia decided to provide four fully functional engines and two mock-ups. It also agreed to supply three more cryogenic engines at a cost of $9 million.

At this point, the Space Commission, which formulates and implements the Indian space programme, approved a Rs.280 crore project to develop an Indian cryogenic engine, the C12.

“We had to get back our people who were already working with the Russian scientists. Then we had to start on our own. They had made some sorts of drawings and designs and they were already working on the engines and fabrication processes with the Russian scientists,” said U.R. Rao, former chairman at Isro. “But still, many things cannot be on paper since there are various processes we go through to make every step as accurate as possible.”

Practical steps

Preparations were made for the first developmental flight of the GSLV-D1 with a procured Russian cryogenic third stage, planned for early 2001. A cryogenic upper stage (CUS) project had also speeded up the design and development of an indigenous engine to replace the Russian one.

“A lot of theoretical studies were conducted under E.V.S. Namboodiry, a propulsion expert who was in charge of studying the cryogenic engine with a team of experts. Something like 18 reports came out regarding cryogenic engine. But theories cannot give you a stage,” said Suresh.

Isro scientists had to become adept in areas such as materials technology, powder metallurgy, welding technology and fabrication technology.

2009-14: Road to success
Even as scientists gained experience from GSLV launches with a Russian cryogenic upper stage engine, they worked feverishly on the indigenous version. In 2009, Isro concentrated on developing infrastructure like the propellant casting facility for solid boosters. That year, Isro reached a landmark when the indigenous cryogenic engine was tested at the Mahendragiri and cleared for a full flight.

But the launch of the flight—the first with an indigenous engine—the GSLV-D3 in April 2010, with a GSAT-4 satellite on board, failed.

The rocket deviated from its path and the vehicle was seen “tumbling” down by Isro scientists. “The thing with rocket launches is that there is not much difference between success and failure. We succeeded (in 2014), but a tiny glitch and we could have ended up in the Bay of Bengal,” said R.V. Perumal, former director of the GSLV project.

The failure, a major disappointment to the nation, was caused by the fact that the cryogenic upper stage could not sustain ignition because the fuel booster turbo pump stopped working 293 seconds into the flight. The second developmental launch of the GSLV D-3 in December 2010 ended in an explosion due to a technical snag in the first stage.
“After the first failure (in 2010), the problem was that we could not recreate the cause of the failure, so it was hard to correct the problem,” said Sivan. “So we listed out possible failures, all feasible reasons for the stopping of fuel booster pump, and took corrective actions for all of them.”

“Even though we would test the engine and the ignition sequence on the ground, the conditions on the flight would be much different,” said Sivan. For Isro, it now became necessary to create those conditions for testing. A high altitude test facility was built in Mahendragiri in 2012 to demonstrate successful ignition for simulated flight conditions. And after testing the system in those conditions, Isro modified the ignition sequence.

Still, in August 2013, a GSLV-D5 launch was aborted at the eleventh hour after a leak was detected in the fuel booster pump. After decades of dogged engineering pursuit, this was an easier problem to solve for Isro.
“When we went ahead with the flight after testing the engine in every possible condition, we were confident of success. We had arrived,” said Sivan.
A short video about ISRO Cryogenic engine development also with the link
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Re: Indian Space Programme Discussion

Post by Varoon Shekhar »

Good article, but once again, short on detail. Without revealing any secrets or classified information, they can still tell the public what it was that gave them the most difficulty all these years- the turbo pump, the propellant lines, the combustion chamber, the special alloys, whatever. They can even say something like, "we came up with a novel solution to the turbo pump issue, or gas generator problem, or piping/channel manufacture", without saying what that solution was.
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Re: Indian Space Programme Discussion

Post by vic »

It seems that ISRO is working on ION propulsion of 13, 75, 235 mN capacity. When these engines are used the weight of GTO satellites will fall by 50%.
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Re: Indian Space Programme Discussion

Post by saip »

vic wrote:It seems that ISRO is working on ION propulsion of 13, 75, 235 mN capacity. When these engines are used the weight of GTO satellites will fall by 50%.
Why the decrease in Satellite weight is an achievement? Did you mean the weight will increase?
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Re: Indian Space Programme Discussion

Post by member_22733 »

It means that for the same design lifespan and same weight of the satellite we can take more functional stuff up there.
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Re: Indian Space Programme Discussion

Post by disha »

ravar wrote:Any foreseeable threat to the SC engine tie-up of ISRO with Ukraine wrt to the regime change there?
Ravarji,

What is the advantage of SC over Cryo?

What are the disadvantages?
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Re: Indian Space Programme Discussion

Post by member_28108 »

Semi cryo easier to handle kerosene or Methane versus liquid hydrogen.Disadvantage is a lower specific impulse compared to LOX H2 (Full cryogenic)
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Re: Indian Space Programme Discussion

Post by disha »

prasannasimha wrote:Semi cryo easier to handle kerosene or Methane versus liquid hydrogen.Disadvantage is a lower specific impulse compared to LOX H2 (Full cryogenic)
Is that the only reason (advantage), that is the temperature for kerosene is high (room temperature) vs. liquid hydrogen?

What are the disadvantages - other than lower specific impulse? Ravarji and PrasannaSimhaji?
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Re: Indian Space Programme Discussion

Post by chetak »

Indian Naval Satellite Rukmini also deployed for the Malaysia airliner search........
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Re: Indian Space Programme Discussion

Post by Indranil »

DRDO Newsletter Vol 34 No 3 March 2014
ADRDE conducts successful testing of Parachute Recovery System for Human Space Programme

Aerial Delivery Research and Development Establishment (ADRDE), Agra, successfully conducted testing of Parachute Recovery System for Human Space Programme of Indian Space Research Organisation (ISRO) on 18 January 2014 by para dropping simulated load weighing 5 ton against actual system requirement of 3.6 ton at Agra Drop Zone using IL-76 Aircraft. The trial preceded a series of eight successful sub-systems level air-drop tests from AN-32 aircraft.

The system has been designed for safe landing of a crew module of 3.6 ton weight class on sea surface. The recovery system consists of a pilot parachute, a drogue parachute and a main parachute.
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Re: Indian Space Programme Discussion

Post by member_28108 »

disha wrote:
prasannasimha wrote:Semi cryo easier to handle kerosene or Methane versus liquid hydrogen.Disadvantage is a lower specific impulse compared to LOX H2 (Full cryogenic)
Is that the only reason (advantage), that is the temperature for kerosene is high (room temperature) vs. liquid hydrogen?

What are the disadvantages - other than lower specific impulse? Ravarji and PrasannaSimhaji?
You can go through this article in Wikipedia gives a perspective of the multitude of advantages and disadvanatges !

http://en.wikipedia.org/wiki/RP-1

The variant of highly purified kerosene or blend is being called as Isrosene
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Re: Indian Space Programme Discussion

Post by member_28108 »

[

The variant of highly purified kerosene or blend is being called as Isrosene[/quote]
http://www.astronautix.com/props/loxosene.htm
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Re: Indian Space Programme Discussion

Post by vic »

saip wrote:
vic wrote:It seems that ISRO is working on ION propulsion of 13, 75, 235 mN capacity. When these engines are used the weight of GTO satellites will fall by 50%.
Why the decrease in Satellite weight is an achievement? Did you mean the weight will increase?
Fuel content, tanks, support structure and chemical engine constitue 60-70% weight of a communication GSO satellite. If this weight is removed then the job of 6 tons communications satellite can be done by a 2 ton satellite. For instance Boeing 702SP all electric satellites with ION propulsion having 48 transponders weights only 1800 kg compared to INSAT & GSAT series weight of 4 tons for 24-36 transponders. Hence, with ION propulsion, GSLV Mark-2 itself can launch satellites with upto 50-70 transponders which in conventional satellites would require GSLV Mark-3 or 4.
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Re: Indian Space Programme Discussion

Post by disha »

prasannasimha wrote: You can go through this article in Wikipedia gives a perspective of the multitude of advantages and disadvanatges !

http://en.wikipedia.org/wiki/RP-1

The variant of highly purified kerosene or blend is being called as Isrosene
Thanks! Not that I am not aware of the link,

in fact, I am of the position that In the Indian context - Semi Cryogenic Engine/Stage is *USELESS*

And given ISRO's fits-and-start on SC Engine/Stage., I do think even ISRO took the position of not going with SC till a certain point.

I still maintain that In the Indian context - Semi Cryogenic Engine/Stage is *USELESS*.

In previous pages, I have given out arguments why it is useless. I will give out more when time permits.
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Re: Indian Space Programme Discussion

Post by Sridhar »

The semi-cryo engine development is not intended as a replacement or substitute for the cryo engine and hence comparing them versus each other is quite meaningless. ISRO's proposed 2MN semi-cryo engine will replace the two hypergolic liquid Vikas engines in the LMV3's L110 core stage to form the core stage of the future ULV series of launch vehicles. Thus, in the ISRO context, the right comparison to make is between the semi-cryo engine and hypergolic liquid engines. Hypergolic liquid engines have their own place in ISRO's future (besides the PSLV and LVM3, they are and will continue to be used for the on-board engines on satellites and for interplanetary spaceships), but the semi-cryo will involve easier handling and lower costs besides providing an ISP boost for the core stage. That is ISRO's stated logic behind the SC development program.

Could you give your logic behind why it is useless?
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Re: Indian Space Programme Discussion

Post by member_28108 »

I was also wanting to know why disha emphatically says it is useless.It is being used as an alternative/ replacement for the initial stages and not as a replacement for the final stages.
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