Indian Space Program: News & Discussion - Sept 2016

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Indranil
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

prasannasimha wrote:
Indranil wrote:The Indian system uses wireless communication to start with.
I was reading up on pad abort testing and the first pad abort test of tge Apollo crew capsule was placed on a booster. This had 3 wires running and if rwo of 3 wires broke it would initiate the abort automatically. The little joe booster went inro an uncontrollable spin due to some defect and started breaking up and the abort command was initiated automatically. This was a succesful abort test with a an unintentional faikure of the booster !
This highlights the importance of redundancy in these systems.
If you see the crew capsule I think those linear ridges hold interstage connections in addition to wireless coms. ( you can see thise very well in the PSLV and Agni missiles too ).
I am sure that they would have multiple redundancies. But Dr. Sivan marked out wireless trigger mechanism as one of the 6 things tested in this round.
prasannasimha wrote: Looks like once they have all the respective units in place tge formal sanction form human space flight will be given.
Taking crew capsule and service module etc we will need at least 15 Tons to LEO.
ULV in the 2*S200 + SC160 + CE25 config would be able to lift 15 ton to LEO.

The lingering question in my mind is that the SC160 cannot be used as a standalone first stage (stick model). In fact, we won't get to a stick model before we get to TSTO which has a 5 Ton to GTO capacity! What about the lower end? I was hoping that ISRO would be design a SC110 stage powered by SCE200 which can be used as the first stage and boosters.

1. SC110 + CE25 would be the stick model which would be similar in capability to PSLV-CA equivalent: 1 ton to GTO.
2. 2*SC110 (boosters) + SC110 (first stage) + CE25 would be the GSLV Mk2 equivalent: 2.5 tons to GTO
4. 4*SC110 (boosters) + SC110 (first stage) + CE25 would be the GSLV Mk3 equivalent: 4.5 tons to GTO or very similar to TSTO with SC500 + CE25. If the later is ready, then it becomes the stick model for beyond 5 tons to GTO payload.

But this is much lower risk model, and a good fall back option. No clustering of SCE200 involved. SC160 will have a 5 mtr, SC400 closer to 7 mtr, all of which are completely knew developments for India. The SC110 would be similar in structure to the current L110 stage.
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Re: Indian Space Programme Discussion - Sept 2016

Post by jaysimha »

ISRO to takeover defunct HMT's 109 acre land on July 14
Read more at: https://www.deccanherald.com/state/isro ... 80699.html

Damn sure if it was upavasi govt.,,,,,,,,,, they would have sold the land and pocketed the money.. just like they did for
Hindustan teleprinters land in guindy chennai.............
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Re: Indian Space Programme Discussion - Sept 2016

Post by putnanja »

ISRO tests higher-thrust Vikas engine, but unfortunately, the press release gives no technical parameters. Not even how much better it is than the current version.


Successful Qualification of High Thrust Vikas Engine
Today (July 15, 2018), a high thrust version of the Vikas Engine was successfully qualified through a ground test for a duration of 195 seconds at ISRO Propulsion Complex (IPRC), Mahendragiri, Tamilnadu. Vikas Engine is the workhorse liquid rocket engine powering the second stage of India’s Polar Satellite Launch Vehicle (PSLV), second stage and the four strap on stages of Geosynchronous Launch Vehicle (GSLV) and the twin engine core liquid stage (L110) of GSLV Mk-III.

All the propulsion parameters during the tests were found satisfactory and closely matched the predictions. This ground test has validated the performance adequacy of the Vikas Engine for its use in the upcoming second developmental flight of GSLV Mk-III. This engine will improve the payload capability of PSLV, GSLV and GSLV Mk-III launch vehicles.
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

Image
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Re: Indian Space Programme Discussion - Sept 2016

Post by JTull »

Chamber pressure increased from 58 bar to 62 bar.
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

JTull wrote:Chamber pressure increased from 58 bar to 62 bar.
DCan you post the source ?
Can someone estimate the advantage that can be got by increasing the chamber pressure by4 bar ? How much can the payload be increased ?
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Re: Indian Space Programme Discussion - Sept 2016

Post by Ashokk »

prasannasimha wrote: Can someone estimate the advantage that can be got by increasing the chamber pressure by4 bar ? How much can the payload be increased ?
With eye on lunar mission, ISRO to test high-thrust Vikas engine
LPSC director V Narayanan told Express that the improved engine would give a significant advantage in terms of enhancing payload capability. “Usually, the chamber pressure is 58 bar, but with the use of high-thrust Vikas engine, we will achieve 62 bar, which is a 6% increase in thrust that gives us 70 kgs of additional payload gain in this mission. Right now, we are going to use the high-thrust Vikas engine only in the second stage. Basically, we are validating it. For Chandrayaan-2 mission, we will be using five such engines aiming for a payload gain of around 250 kgs,” Narayanan said.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

The vacuum-lit version was already flight tested on last GSLV launch. This is the ground lit version.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Varoon Shekhar »

^
Thanks for pointing that out, I was about to mention that the upgraded Vikas has already been flight tested. Simply put, the second stage Vikas has been developed and successfully flown in a GSLV. This most recent test was of a strap on, correct? Will a 250kg improvement be sufficient for the Chandrayaan-2 which is over 3000kg? There was also an upgraded CUSP engine that was going to be flown soon (C-15), so probably that will cover the increased weight of the Chandrayaan spacecraft.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Varoon Shekhar »

Is everything on course for the Chandrayaan-2 mission in October? And why no launches in July or August, after earlier talking about one launch each in the two months?
Issues with GSAT and PSLV have cuased issues that delayed things as everything has to be recjhecked and recertified so it is obvious that this will cause delays. Chandrayaan rover is going through various qualifications etc so the final launch date will be still fluid.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

ISRO is not being able to keep up with the launch rate. REquired by the nation > ISRO's target > achieved launches.

GSLV Mk2 is not putting Chandrayaan to GTO, but LTO. It can carry larger load to LTO.

They were trying to first get to a reliable GSLV config. Now they will try to increase the payload to 3.2 tons. HTVE on the second stage and full burn of the CUS were the first two improvements. Next is HTVEs on the strap ons. This will not only increase efficiency of the strap on motors, but also decrease the time that the empty weight of the S139 is carried by about 7 seconds. That total improvement in payload will be about 250 kgs. They will also increase the fuel in the CUS and the burn rate. This will also increase the payload by a couple of 100 kgs. For the last few 100 kgs, they will have to decrease the empty weight of the CUS stage.
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

The lander is being tested etc so the actual launch may get further delayed. There are many things being done for the first time so I dont think a hard schedule will be possible.
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

Launch window for maximum sunlight will be required too as this does not have an RTG and is solar panel dependent
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Re: Indian Space Programme Discussion - Sept 2016

Post by dinesha »

Indranil wrote:ISRO is not being able to keep up with the launch rate. REquired by the nation > ISRO's target > achieved launches.

GSLV Mk2 is not putting Chandrayaan to GTO, but LTO. It can carry larger load to LTO.

They were trying to first get to a reliable GSLV config. Now they will try to increase the payload to 3.2 tons. HTVE on the second stage and full burn of the CUS were the first two improvements. Next is HTVEs on the strap ons. This will not only increase efficiency of the strap on motors, but also decrease the time that the empty weight of the S139 is carried by about 7 seconds. That total improvement in payload will be about 250 kgs. They will also increase the fuel in the CUS and the burn rate. This will also increase the payload by a couple of 100 kgs. For the last few 100 kgs, they will have to decrease the empty weight of the CUS stage.
Electro-mechanical actuators using Lithium Ion batteries will also lead to the improvements in payloads.

http://esmats.eu/esmatspapers/pastpaper ... prasad.pdf
The benefits of electromechanical actuators includes,
• Simple configuration and less number of components
• Reduced system weight and cost
• Easy fault detection and isolation scheme
• No life restricting elements
• Reduction in system development and test efforts
• Less lead time for flight readiness
• No launch count down operations
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Re: Indian Space Programme Discussion - Sept 2016

Post by dinesha »

http://www.newindianexpress.com/states/ ... 93608.html
The next generation Vikas engine developed by the Liquid Propulsion Systems Centre (LPSC) is being flown for the first time. LPSC director V Narayanan told Express that the improved engine would give a significant advantage in terms of enhancing payload capability. “Usually, the chamber pressure is 58 bar, but with the use of high-thrust Vikas engine, we will achieve 62 bar, which is a 6% increase in thrust that gives us 70 kgs of additional payload gain in this mission. Right now, we are going to use the high-thrust Vikas engine only in the second stage. Basically, we are validating it. For Chandrayaan-2 mission, we will be using five such engines aiming for a payload gain of around 250 kgs,” Narayanan said.

Another important experiment that the national space agency is attempting is last depletion mode shutdown. Generally, scientists store extra propellant in the tank and cut off the upper cryogenic stage after reaching desired velocity. However, this time they are attempting to deplete the liquid oxygen, which means using up another 60-70 kgs of propellant in order to achieve 4-5 seconds of additional burn duration.

Narayanan said this would be the best way of mission planning and optimum utilisation of propellants. “All these new things are being done keeping lunar mission in the mind and ISRO’s bigger game plan to increase GSLV payload capability. For Chandrayaan-2, we are formulating a perfect combination. The four strap-ons and second stage will be boosted with high-thrust Vikas engines; cryogenic upper stage will be loaded with enhanced propellants of 15 tonnes instead of current 12.8 tonnes and will be operated with 9.5 tonne thrust compared to the present 7.5.

ISRO chairman K Sivan told Express that the high-thurst Vikas engine has been under development for the past three years and is robust. It has cleared several tests, he said. “It was developed as part of ISRO’s plans to have GSLV launches with heavier payloads. GSLV Mk2 and GSLV Mk 3, when stabilised, will have huge international demand.”On introduction of electromechanical actuation system in place of electrohydraulic actuation in the second stage of the rocket, Sivan said the new system is simpler and more robust, which increases the vehicle’s reliability.
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Re: Indian Space Programme Discussion - Sept 2016

Post by nachiket »

Indranil wrote:ISRO is not being able to keep up with the launch rate. REquired by the nation > ISRO's target > achieved launches.

GSLV Mk2 is not putting Chandrayaan to GTO, but LTO. It can carry larger load to LTO.

They were trying to first get to a reliable GSLV config. Now they will try to increase the payload to 3.2 tons. HTVE on the second stage and full burn of the CUS were the first two improvements. Next is HTVEs on the strap ons. This will not only increase efficiency of the strap on motors, but also decrease the time that the empty weight of the S139 is carried by about 7 seconds. That total improvement in payload will be about 250 kgs. They will also increase the fuel in the CUS and the burn rate. This will also increase the payload by a couple of 100 kgs. For the last few 100 kgs, they will have to decrease the empty weight of the CUS stage.
Would it have made more sense to use the MkIII for the Chandrayaan II launch considering the number of changes necessary int he MkII due to the higher weight?
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

No. The changes on Mk2 are in line with what they wanted to do anyhow. Our mass fractions are not really good. We need to improve significantly from the current 0.5% to 1% (GSLV Mk3 with SC160) and higher. Going higher than that with solids would be very difficult. And that is why I was wondering why ISRO is not studying using SCE200 engine on strapons except for the clustered version on UHLV.
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Re: Indian Space Programme Discussion - Sept 2016

Post by kit »

Indranil wrote:ISRO is not being able to keep up with the launch rate. REquired by the nation > ISRO's target > achieved launches.
.

instead of incremental improvements, a much heavier payload rocket would be able to carry multiple satellites to orbit.

or build one more launch facility will full private participation and let them build parallel to what ISRO does

both easier said than done .. without government support private players will be quite risk averse.

demand for transponders is just going through the roof
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Re: Indian Space Programme Discussion - Sept 2016

Post by Haridas »

dinesha wrote:http://www.newindianexpress.com/states/ ... 93608.html
.....Narayanan said this would be the best way of mission planning and optimum utilisation of propellants. “All these new things are being done keeping lunar mission in the mind and ISRO’s bigger game plan to increase GSLV payload capability. For Chandrayaan-2, we are formulating a perfect combination. The four strap-ons and second stage will be boosted with high-thrust Vikas engines; cryogenic upper stage will be loaded with enhanced propellants of 15 tonnes instead of current 12.8 tonnes and will be operated with 9.5 tonne thrust compared to the present 7.5.” ..... .
The increase fuel load in CUS necessarily requires using the engine in the uprated thrust mode compared to traditional mode where boosted thrust mode is used only till gravity loss reaches zero (i.e. min altitude insertions, such that trajectory does not drop below 100 km altitude) , there after it is all about increasing orbit and cryo thrust does not matter.
The increased CUS fuel is supported by the higher chamber pressure Vikas. BTW the Chinese earth storable liquid engine's chamber pressure (20 years ago) was always much higher (IIRC ~68 bar) than Vikas. Better late than never.

~ 25 years ago HP-India supplied the data acquisition system for LPSC when it was being established.
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Re: Indian Space Programme Discussion - Sept 2016

Post by jaysimha »

http://pib.nic.in/newsite/pmreleases.aspx?mincode=14

Department of Space19-July, 2018 16:06 IST
Launching of Replacement Navigation Satellite

Indian Space Research Organisation has launched IRNSS-1I on 12th April, 2018 to replace IRNSS-1A. IRNSS- 1I carried refurbished Atomic clocks.

IRNSS 1A had failure of three Rubidium atomic clocks and IRNSS constellation is functioning with only six satellites. The move to launch the replacement satellite for IRNSS 1A was imperative to complete the seven satellite NavIC constellation. However, IRNSS-1A is still being used for messaging services. The Rubidium clocks were from the same Swiss company. The clocks of NavIC and GALILEO developed problems that were similar in nature.

A thorough analysis and simulation on the failure of the atomic clocks was done. Finally, it was traced to one of the feed through capacitor carrying the DC supply to the physics package, getting in to problem due to excess temperature rise. This was corrected in the IRNSS-1I clocks.

This information was provided by the Union Minister of State (Independent Charge) Development of North-Eastern Region (DoNER), MoS PMO, Personnel, Public Grievances & Pensions, Atomic Energy and Space, Dr Jitendra Singh in written reply to a question in Rajya Sabha today.
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Re: Indian Space Programme Discussion - Sept 2016

Post by AdityaM »

India's Key Spy Satellite Maker Sacked, Made Advisor To ISRO Chairman
Dr Misra was the architect of India's spy satellite RISAT 1, which died in orbit under mysterious circumstances due to an implosion that was reported and noticed first by NASA and not by ISRO.
The satellite imploded! Any news ever discussed on this here?

ok, so gagan pointed to something here in Jul2017: viewtopic.php?f=3&t=7248&p=2185192&hili ... 1#p2185192
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Re: Indian Space Programme Discussion - Sept 2016

Post by Varoon Shekhar »

https://economictimes.indiatimes.com/ne ... 098924.cms

" Giving a big push to the Modi government’s Make-in-India programme, Indian Space Research Organisation (Isro) has bought the technology for space solar cells from the US and will ma .. "

At least one layman had no idea that there were that many solar cells in a satellite! What exactly is the technological/infrastructural/financial challenge in developing and producing them in India. Has India or ISRO never made space grade solar cells until now, for any satellite, from the Rohinis right until GSATs?
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Re: Indian Space Programme Discussion - Sept 2016

Post by Trikaal »

^Good initiative by ISRO. Should give a boost to the local satellite making industry. The question is, why did they wait until now to do this?
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Re: Indian Space Programme Discussion - Sept 2016

Post by disha »

^^ Please check the image below:

https://en.wikipedia.org/wiki/Solar_cel ... 80716).jpg

For solar cells for satellite, which technology will you use? And why?

For residential usage, which technology will you use? And why?
Indranil
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

Indranil wrote: The lingering question in my mind is that the SC160 cannot be used as a standalone first stage (stick model). In fact, we won't get to a stick model before we get to TSTO which has a 5 Ton to GTO capacity! What about the lower end? I was hoping that ISRO would be design a SC110 stage powered by SCE200 which can be used as the first stage and boosters.

1. SC110 + C25 would be the stick model which would be similar in capability to PSLV-CA equivalent: 1 ton to GTO.
2. 2*SC110 (boosters) + SC110 (first stage) + C25 would be the GSLV Mk2 equivalent: 2.5 tons to GTO
4. 4*SC110 (boosters) + SC110 (first stage) + C25 would be the GSLV Mk3 equivalent: 4.5 tons to GTO or very similar to TSTO with SC500 + C25. If the later is ready, then it becomes the stick model for beyond 5 tons to GTO payload.

But this is much lower risk model, and a good fall back option. No clustering of SCE200 involved. SC160 will have a 5 mtr, SC400 closer to 7 mtr, all of which are completely knew developments for India. The SC110 would be similar in structure to the current L110 stage.
I did not realize that I was closely describing the Angara rocket family. The engine (RD191) for the first stage and boosters are near identical to SCE200. On Angara, the booster/first stage carry 130 tonnes of kerosene+oxygen each and has a 2.9 mtr diameter. We could have ours to have a 2.8 mtr diameter and take the CE15 stage as is. The resultant stick model will have near identical shape and capability as PSLV-CA.

Anyhow, if wishes were horses ...
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

The plan is for clustered engines after the SCE 200 is developed
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

I am aware of that Prasanna ji. That stage called CSC-400. Just like ISRO is proposing that the CSC-400 stage be used as the common first stage and booster to obtain payload capabilities between 5-25 Tons to GTO, I am wondering why not develop a SC130-ish stage which works as the common first stage and booster to obtain payloads between 1-5 tons? That would provide great simplicity to design, TOT and manufacturing besides providing economies of scale.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Haridas »

^^^ what is the market cost compititiviness addressed with development investment for 25 tonn to GTO?
How is indian market projections unfolding (for that is captive business)?
At what point ISRO lose competitive advantage versus reuseable booster based SpaceX?

I think at this moment half the effort should be in cost compititiviness technologies.

ISRO needs seriously more investment imho.
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Re: Indian Space Programme Discussion - Sept 2016

Post by ramana »

Indranil wrote:I am aware of that Prasanna ji. That stage called CSC-400. Just like ISRO is proposing that the CSC-400 stage be used as the common first stage and booster to obtain payload capabilities between 5-25 Tons to GTO, I am wondering why not develop a SC130-ish stage which works as the common first stage and booster to obtain payloads between 1-5 tons? That would provide great simplicity to design, TOT and manufacturing besides providing economies of scale.

You need to do a trade study for all up configurations and get the best option.
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

^^ The reusable roxket program work is going on. Winged rentry, Vertical landing and Bagged landing are all being worked out. One grpup is working on winged reentry (RLV) and anpther group on vertical landing and parachute + air bagged landing.
Dr Somnath was heading or directing the vertical lander team when he was in LPSC if my memory is correct. In one of the videos posted recently the test vehicke for booster recovery was shown alo g with a flight abort test vehicle for the crew capsule
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

Haridas wrote:^^^ what is the market cost compititiviness addressed with development investment for 25 tonn to GTO?
How is indian market projections unfolding (for that is captive business)?
At what point ISRO lose competitive advantage versus reuseable booster based SpaceX?

I think at this moment half the effort should be in cost compititiviness technologies.

ISRO needs seriously more investment imho.
Actually, I Was thinking along those lines only. It makes all the more sense to go the common core or booster. The world is moving in that direction for obvious economic reasons. ISRO will have a great engine in the SCE200 to go this way, but it looks like they want to back on the solid boosters. I can't see how that is cost effective.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

ramana wrote:
Indranil wrote:I am aware of that Prasanna ji. That stage called CSC-400. Just like ISRO is proposing that the CSC-400 stage be used as the common first stage and booster to obtain payload capabilities between 5-25 Tons to GTO, I am wondering why not develop a SC130-ish stage which works as the common first stage and booster to obtain payloads between 1-5 tons? That would provide great simplicity to design, TOT and manufacturing besides providing economies of scale.

You need to do a trade study for all up configurations and get the best option.
I have a small excel sheet on my end where I am doing first order calculations. What I was proposing turns out to be very close to the reality as shown by Angara family. I don't intend to say I know more than ISRO. I just want to know why they are not going down this obvious path.

For example, the final (slightly suboptimal) GSLV configuration was governed by the launch site design!
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

Solid rocket boosters still will be used as they are cheap in various aspects - earth storable, low lead time to manufacture and have got high energy energy density . Once they master semicryo they will slowly phase them out. Even the SLS system will be using solid rocket boosters.So they will have some role but will be phased away as other systems improve.
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Re: Indian Space Programme Discussion - Sept 2016

Post by SriKumar »

Indranil wrote:
ramana wrote:

You need to do a trade study for all up configurations and get the best option.
For example, the final (slightly suboptimal) GSLV configuration was governed by the launch site design!
Design or location? If design, that's funny/interesting. I am assuming it has to do with either the strength of the foundation i.e. how much thrust it can take (less likely) or the size of the conduits to channel the thrust away from the pad (more likely). Or may be related to vibration damping.
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

The last stage burn time has to be adjusted such that spent stages does not fall over Indonesia. This is a unique requirement for Indian GSO launches
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

SriKumar wrote:
Indranil wrote: For example, the final (slightly suboptimal) GSLV configuration was governed by the launch site design!
Design or location? If design, that's funny/interesting. I am assuming it has to do with either the strength of the foundation i.e. how much thrust it can take (less likely) or the size of the conduits to channel the thrust away from the pad (more likely). Or may be related to vibration damping.
The book "From Fishing to Red Planet" hosted on ISRO's website gives great details on the evolution of the GSLV vehicle and the many configurations proposed. The chapter on GSLV is authored by R.V. Perumal who was the project director of PSLV and GSLV projects. He says,
It should be noted that from the early 1980s the various candidate configurations for GSLV indicated a strong need for modular solid strap-on. Till 1984 no substantial progress was made in the design of the PSLV launch pad. An opportunity was available to build the facility which would cater to the needs of the launch vehicle configurations that were emerging as candidate configurations of GSLV. Unfortunately this was missed. Later this became the single significant factor in determining the final booster configuration of GSLV-Mk II.
prasannasimha wrote:The last stage burn time has to be adjusted such that spent stages does not fall over Indonesia. This is a unique requirement for Indian GSO launches
While this is true, most are working with tighter constraints. By its own admission, ISRO says that it has the second best launch site in the world in terms of location.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Indranil »

Agnikul is a new startup which is trying to come up with their first launch vehicle called Agniban. It will be a two stage launcher capable of launch 100 kgs to 700 km LEO. 7-clustered Kerolox engines for the first stage. Each engine is additively manufactured. They want to lower the cost of launching small satellites from the current $40,000 per kg to $10,000 per kg.

http://agnikul.in​
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

Mylawami Annadurai retired on 231st he was Director of UR Rao Space Centre.
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Re: Indian Space Programme Discussion - Sept 2016yhe

Post by amritk »

disha wrote:^^ Please check the image below:

https://en.wikipedia.org/wiki/Solar_cel ... 80716).jpg

For solar cells for satellite, which technology will you use? And why?

For residential usage, which technology will you use? And why?
Hi Disha,

For space it would generally be the three junction non-concentrator cell, because it is the state of the art. High efficiency, radiation hard and well supported by the vendors for this application.

For residential, it would be the single junction non-concentrator. Reasonably efficient, produced in high volume and cheap. 200x cheaper than space solar cells.

Non-concentrator means no lenses, mirrors etc are used to increase intensity. It is designed for natural sunlight.
Neela
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neela »

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OUR ROCKET: AGNIBAAN
A launch vehicle capable of carrying up to 100 kg of payload, to low Earth orbits up to 700 km with a plug-and-play engine configuration for an air launch vehicle.
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