Indian Space Program: News & Discussion

[rahulm]

Ahead of the imminent launch, collecting info:

Chandrayaan 3 details. Some nice CAD renderings here not seen in the Brochure

Curtain raiser video

https://www.isro.gov.in/chandrayaan3_gallery.html

The first post launch parameter to check will be the injection orbit after separation from CUS25 - marking it here as 170 +/- 3.5 kms x 36,500 +/- 500 kms and inclination 21.3 deg from the Brochure.

[Ashokk]

Chandrayaan-3: Isro pins hopes on lessons from failure; definitive 1st orbit, larger landing site, better error corrections introduced

Isro chairman S Somanath told TOI that LVM3 will place Chandrayaan-3 in an apogee (farthest point from Earth) of 36,500km as against 45,475km during Chandrayaan-2. The perigee (closest point to Earth) will be around 170km, nearly the same as last time. “This is being done to get more stability,” he said.
4+1 Earth-Bound Manoeuvres
Another scientist explained: “In Chandrayaan-2, we took the ‘burn to depletion’ — use the last drop of fuel — approach with the cryogenic upper stage to achieve high altitude. However, that creates post-launch tracking challenges given that we use international stations. So, we’ve decided to go to a definitive orbit (36,500km), making initial tracking and operations that follow more efficient.”

Isro will then conduct multiple Earth-bound manoeuvres to increase Chandrayaan-3’s orbit before commands for trans-lunar insertion (TLI) that will kick off the spacecraft’s journey towards Moon, are given. Multiple scientists explained that Isro will perform four major manoeuvres — No 1, 3, 4 and 5 — to raise the apogee, while the second manoeuvre will be a minor perigee-rising one.

TLI Expected On July 31
If all goes as planned, TLI will be done on July 31.
Chandrayaan-3 will then travel towards Moon for about five-and-a-half days and lunar orbit insertion is expected around August 5. These are estimations for nominal performance.
“Spacecraft will initially be on a greater apolune (farthest point from Moon) and we’ll do multiple perilune (closest point) manoeuvres to reduce altitude eventually to a 100km X 100km circular orbit. It’s too early to speak about exact dates for this milestone,” one scientist explained, adding there could be around five lunar-bound manoeuvres before the final descent phase.
After Chandrayaan-3 reaches 100km X 100km orbit, the lander module (Vikram & Pragyan) will separate from the propulsion module and be eventually brought to a 100km X 30km orbit, from where commands for deboost and final descent is expected on August 23.

[disha]

I have started a topic to track C3 Launch and discussions. viewtopic.php?p=2594764#p2594764

Copied some of the C3 posts into that topic thread. And continue monitoring that thread.

[sanman]

[SSridhar]

ISRO Unveils Vital Facilities for Solid Motor Advancement - ISRO

Today, at the Satish Dhawan Space Centre (SDSC-SHAR), a group of vital facilities essential for the enhancement of solid motor realization were inaugurated by Shri Somanath S., Chairman, ISRO/Secretary, Department of Space. Shri A. Rajarajan, Director of SDSC-SHAR, and Directors from other ISRO Centres/Units were present.

SDSC-SHAR isresponsible for the development of solid motors/segments for ISRO's acclaimed launch vehicles including PSLV, GSLV, LVM3, and SSLV. It aims establishing 29 primary and 16 auxiliary facilities to bolster solid propellant processing capabilities striving to achieve 2X improvement in its capacity. Commencing the first phase of this initiative, today's inauguration unveiled five key facilities dedicated to solid propellant mixing, casting, machining, as well as the non-destructive testing of cast segments.

[disha]

https://swarajyamag.com/science/chandra ... ound-earth

The author above makes a very mis-leading statement

//However, until that happens, ISRO wouldn't be counted among the big boys of space exploration.//

The discussion on cryo- engines and stages veer offs into launch vehicle payload capacity and then the self-denigrating categorization of big boys vs small boys is made. Author needs to remove that line. Here are the facts:

1. The Staged Combustion Cryo- engine is one of the most complex cryo- engine in the world. ISRO with a specific impulse of 454 seconds (451s to 457s) and throttable from 73.55 kN to 82 kN. It is designed as an upper stage. It is comparable to any upper stage engine in any of the rocket launch families across the world. In some cases it is even better. Will come to that later.

2. China does *NOT* have a staged combustion engine. Its best, gas expander engine has a SI of 442 seconds. ISRO's cryo- engine (naughty boy) is more efficient. Even at 2% efficiency, the payload mass fraction and the velocity imparted to payload adds up. Here, China is NOT in the same league as ISRO and infact is far behind.

3. Coming back to upper stage rocket engines, no country other than Russia and India have a cryo- upper stage which is staged combustion. Please check it out. That puts both India and Russia on a league of their own. And India ahead of Russia, since Indian CUS (staged combustion) has higher thrust (it can throttle upto 82kN). Yes, here US, France, Japan and China are behind. China is the tail end of it.

The comparison should be apples to apples. Not red grapes to watermelons. So looking at CUS of all countries, and the ones that are in active use: the only two engines ahead of ISRO's naughy boy is Vinci from France and RD0146 from Russia, Both are expander based and there is a limit to thrust in expander based engines due to the square-cube law.

Coming back to the payloads (on how much tonnes one can launch on a single launch rocket), China's payload capacity does not count. They have the most unsafe rocket program in the world which actually kills innocent people by dozens. By that measure, China does not have a credible rocket program.

What matters is not the size of the payload, but the cost efficiency of the launch rocket. If ISRO can launch 10 tonnes to LEO at one-fourth or half the cost, reliably and safely, it has far better rocket program than any other in the world.

Given the above information, I do urge the author to take out "left field subjective statement" about boyhood from an otherwise excellent article.

[sanman]

2. China does *NOT* have a staged combustion engine. Its best, gas expander engine has a SI of 442 seconds. ISRO's cryo- engine (naughty boy) is more efficient. Even at 2% efficiency, the payload mass fraction and the velocity imparted to payload adds up. Here, China is NOT in the same league as ISRO and infact is far behind.

From what I've read, China does in fact have staged combustion engines.

https://en.wikipedia.org/wiki/YF-90

https://en.wikipedia.org/wiki/YF-100

https://en.wikipedia.org/wiki/YF-130 (in development)



I personally think we should have first gone for expander cycle engine or even gas-generator, because those were easier and we could have gotten flying much sooner. We should have also gone with semi-cryogenic instead of full-cryogenic, because that too was easier. Liquid hydrogen is a very difficult substance to handle.

[SSridhar]

I will use a different argument, disha. China's space program has been for three major reasons: exploitation of space resources for self; weaponization of space; and, prestige. All these come from that urge to be the 'Middle Kingdom'. So, it took a particular trajectory. Secondly, of course, wealth matters. China has, for a while, been wealthier than us.

[sanman]

disha, China has now also become the first country to launch a methane-lox rocket to space:

[sanman]

Lockheed-Martin's subsidiary Voyager has apparently signed a MoU with ISRO to make use of its Gaganyaan crewed flight capability to send astronauts to Starlab (Voyager's space station):




https://timesofindia.indiatimes.com/cit ... 682632.cms

Voyager inks pact to use Gaganyaan spacecraft to service Starlab

Bengaluru: The Indian National Space Promotion and Authorisation Centre (IN-SPACe) and Isro Human Space Flight Centre (HSFC) have recently signed an MoU with US’ Voyager Space (Voyager) to explore opportunities for the utilisation of the Gaganyaan crewed spacecraft to service Starlab, a first-of-its-kind, continuously crewed, free-flying space station.

IN-SPACe director-promotions Vinod Kumar told TOI: “The MoU was signed between us, IN-SPACe and HSFC on the second day (July 7) of the G20 SELM (Space Economy Leaders Meeting) in Bengaluru. IN-SPACe will work to explore further opportunities and enable collaborations onboard Starlab.”

According to the MoU, the aim is to jointly study the potential of Gaganyaan spacecraft to provide crewed flights to the Starlab, while Voyager and IN-SPACe will seek further collaborations with various stakeholders within the Indian space ecosystem, including research institutions, commercial entities, and government agencies.

The agreement, according to officials in the HSFC, is in line with the centre’s future goals, especially the objectives of conducting micro-gravity experiments.

Aside from this, as TOI had reported earlier, Isro and IN-SPACe are in talks with Jeff Bezos’ Blue Origin, which is is keen on using India’s GSLV-Mk3 or LVM-3 as a crew capsule to service its proposed Orbital Reef, a Low Earth Orbit (LEO) space station being designed for commercial space activities and space tourism uses.

Vinod Kumar said: “The talks with Blue Origin are going on and we will comment on the matter when more progress is made.”

With more than 35 years of spaceflight heritage and more than 2,000 successful missions, Voyager Space said it was dedicated to building a better future for humanity in space and on Earth.

It also mentions that Blue Origin is interested in Gaganyaan to service their planned Orbital Reef space station too.

[SSridhar]

Chandrayaan-3 a shot in the arm for Gaganyaan-1 - ToI

The perfect launch of Chandrayaan-3 on Friday has come as a shot in the arm for Gaganyaan-1. For, a modified version of the same rocket — LVM-3 — will be used for India’s maiden manned mission.

“LVM-3 has injected Chandrayaan-3 into the precise orbit, once again proving it is the most reliable heavy-lift vehicle of Isro,” said S Mohan Kumar, project director of LVM-3 and mission director of Friday’s launch.

He said the rocket used multiple systems that are being human-rated (enhancing reliability to ensure safety of humans being transported).
“For Friday’s launch, we used the human-rated solid strap-on motors. The L110 Vikas engine is also human-rated,” he said. TOI had reported about Isro’s plans to use human-rated systems on LVM-3 launches that aren’t part of the Gaganyaan mission so as to re-ascertain their capability.

Isro chairman S Somanath said this is part of making all rockets more efficient and reliable. “All human-rated elements will now start flying even on non-human-rated LVM-3 missions. The last mission had the human-rated S200s and in the next mission, more such elements will be added,” Somanath told TOI ahead of Friday’s launch.

The Isro chairman said the rating of the Gaganyaan launch vehicle is almost done. “The propulsion modules — solid, liquid and cryogenic — have undergone tests successfully and the remaining elements of the rocket have been reverified and qualified to the extent that we can call them human-rated,” he said.

S Unnikrishnan Nair, director, Vikram Sarabhai Space Centre, which produces LVM-3, said the teams have met all targets. “We are implementing some human-rated systems as and when we can in missions like today’s. Except for quad-electronics (electronic systems that will have quadruple redundancies), which will only be tested on the first crewless mission (planned next year), all human-rated systems have been tested. The software is being tested,”

A modified version of rocket LVM-3 will be used for India’s maiden manned mission Gaganyaan-1.

[sanman]

I hope ISRO /NSIL can capitalize off the success of Chandrayaan, Gaganyaan and similar high-profile missions to attract private partners for NGLV program, which in my opinion will be the biggest game-changer yet for ISRO, by providing reusaiblity.

[Atmavik]

I hope ISRO /NSIL can capitalize off the success of Chandrayaan, Gaganyaan and similar high-profile missions to attract private partners for NGLV program, which in my opinion will be the biggest game-changer yet for ISRO, by providing reusaiblity.

Somnath sir has mentioned industry participation in a couple of interviews. Looks like there is a plan . This can be a game changer for our industrial capacity

[sanman]

I hope ISRO /NSIL can capitalize off the success of Chandrayaan, Gaganyaan and similar high-profile missions to attract private partners for NGLV program, which in my opinion will be the biggest game-changer yet for ISRO, by providing reusaiblity.

Somnath sir has mentioned industry participation in a couple of interviews. Looks like there is a plan . This can be a game changer for our industrial capacity

I'm really happy about S Somnath when I compare him with other past ISRO chiefs. He seems very able. I expect him to have a productive and successful tenure.

His plan to develop reusable NGLV (Next-Generation Launch Vehicle) within next 5 years through private industry partners is marvelous. This can give India its own SpaceX.
We need to graduate to this level.

[sanman]

Watch this one guys - interviews with assorted Indian private sector space companies, where they talk about their business offerings:

[SSridhar]

Mystery object that washed up on Australian coast is 'upper-stage engine from Indian rocket' - AP/ToI

Authorities in Canberra are currently investigating whether a cylindrical object, resembling a small car, that washed up on a remote Australian beach is space debris from a foreign rocket. The discovery of the object at Green Head, located approximately 250 kilometers (155 miles) north of Perth, prompted police to cordon off the area on Sunday.

The Australian Space Agency is collaborating with other international space agencies to determine the origin of the object, which appears to be constructed partially from a woven material. In a tweet, the agency stated, "The object could be from a foreign space launch vehicle, and we are coordinating with global counterparts who may provide further information."

According to European Space Agency engineer Andrea Boyd, her colleagues believe that the item washed up in the Indian Ocean is a component of an upper-stage engine from an Indian rocket used for various missions. Speaking to the Australian Broadcasting Corp, Boyd mentioned that based on its shape and size, they are quite certain about its identity.

Responsibility for the object's disposal lies with the entity that launched it into space. Boyd explained that the United Nations Office for Outer Space Affairs oversees an outer space treaty, which mandates that the entity responsible for launching an object remains accountable for it until the end of its lifecycle.

[sanman]

Why wouldn't this be a better way to power surface vehicles and other infrastructure on the Moon or Mars?



Come to think of it, this could usefully power surveillance equipment in the remote high mountain border areas, etc

Why can't ISRO try a demonstration project for this, just to power something in one of our remote areas, perhaps near the LOC/LAC?

Then if it works, we could also try to do it on Moon or Mars.
(It would be especially useful to help a rover survive the long cold lunar night.)

[sanman]

[sanman]

Test of Gaganyaan Service Module thrusters:

[disha]

Lockheed-Martin's subsidiary Voyager has apparently signed a MoU with ISRO to make use of its Gaganyaan crewed flight capability to send astronauts to Starlab (Voyager's space station):

I think the above is enabled due to Artemis accord. Coming to think about it, a sustained space exploration can happen only by collaborative-competitive aspect. Like "Coop-etition", a portmanteau of Cooperation-Competition.

For example, Arianne/ESA does not have any heavy lift capability left until Ariane 6 comes online and since Ariane 5 is now retired. Of course ESA will look at NASA and US private operators like SpaceX/Delta etc. Similarly the US operators both private and public will want additional payload capacity and similarly ISRO will want to use NASA deep space network etc. For example, once C3 makes it to Moon, ISRO will have two observation platforms plug'ed into ISRO's communication network that can help all future missions to moon (till of course the moon-sats retire).

disha, China has now also become the first country to launch a methane-lox rocket to space:

Yes, congratulations to them and a major achievement. We have been running around semi-cryo like a dog chasing its own tail since last 20 years. We developed and flew two seemingly more complex LOH-LOX cryo engine in that time. I say "seemingly", since it is complex, but in two decades we mastered two different cryo- stages (engines, stage, development flights, op flights, infrastructure) and the semi-cryo is still having hiccups on the test stand.

It was very evident, once we mastered cryo-, the next step would be to:

* look at similar cryo- like MethoLox OR not at all explore similar cryo but...
* ... scale up the existing ones.

Since Semi-cryo (with Isrosene etc) is a specialized process it was bound to have severe hurdles. The issue is not with technology, but with chemistry.

First we went through signing an agreement with Ukraine of all places, 2 decades back that too. That was wrong, because we were not going to get "technology transfer" and we already had a path into Cryo- via GSLV Mk1.

Then we went and signed a deal with Roscosmos. To test SCE200 in Russia while our own test stand was being built. Then we went back to Ukraine to test critical components.

In effect, ISRO was muddling around without a clear cut plan for the future. I can only say, let it muddle along SCE. That will be throwing good money behind bad instead of walking away from a bad investment.

Now news comes that ISRO has developed a metholox demonstrator engine of 200kN and plans to go for 5MN (5 Mega Newton) engine. And the 200kN came in record time. Why was this not picked up 10 years back? Even now they should go forward and operationalize the 200 kN metholox engine.

Anyway, from my perspective, ISRO must

* Develop 2-5 mN Metholox Engines
* Develop 70-140 kN variable thrust, 200 kN to 2-5 mN cryo- engines of various types, GG/Staged-Combustion/Expander etc.
* Restartable upto several times Metholox/Cryo- engines
* Reusable metholox/cryo- stages.
* Indian private sector can pick up small scale engines like metholox/LOH/LOX 2-5 kN restartable electric motor driven engines.

ISRO has the technical manpower and the budget to go full fledge on the above. Just get rid of the useless SCE program.

Once we have the engine building blocks and standardized (since its either LOH/LOX or LOX/CH4) engines and stages and the infrastructure to go for it, ISRO can start doing plug and play.

ISRO has already developed a remarkable lead in solid-boosters. So pairing with solid boosters with above building blocks on a "factory" mode will make India an unbeatable space power.

[disha]

From what I've read, China does in fact have staged combustion engines.

https://en.wikipedia.org/wiki/YF-90

https://en.wikipedia.org/wiki/YF-100

https://en.wikipedia.org/wiki/YF-130 (in development)

Sanmanji, YF-90 is still in development. And it might fly in 2025. That is a complete 20 years or two decades behind ISRO. At the same time, it is rated to be 2 mN which is impressive. ISRO can evolve its CE-7.5 to CE-75 (or 750kN) and cluster it into three or five. Or straight away go for 2-3 mN. Even if it comes by 2030, we are good. Anyway, YF-90 is designed for first stage and CE-7.5 is for upper-stage. So again orange to apples from my perspective.

YF-100 is semi-cryo and is used as first stage. Further different from the context of cryogenic upper stage.

YF-130 is still in development. ISRO can evolve its CE-7.5 (~75 kN) to CE 75 (~750 kN).

So on cryogenic upper stages, we do have a ace in hole.

Again all this started because the author of article claimed that "ISRO is not in big boys club". That is a very subjective interpretation. By that standard, Cheenis space program is not in any respectable club at all...*

I personally think we should have first gone for expander cycle engine or even gas-generator, because those were easier and we could have gotten flying much sooner. We should have also gone with semi-cryogenic instead of full-cryogenic, because that too was easier. Liquid hydrogen is a very difficult substance to handle.

LOH is difficult to handle, but Semi-cryogenic (Kerosene) is even more difficult to manage. Nothing stops us from going with expander cycle now and we now have both Gas Generator and Staged Combustion engines. We can continue to build on that and get the metholox going. We have a demonstrator metholox which has been developed in record time. We need to double down on that.

* I always find it difficult to consider Cheeni space program credible. Particularly after it destroyed an entire town and did not own it up.

[sanman]

I think the above is enabled due to Artemis accord. Coming to think about it, a sustained space exploration can happen only by collaborative-competitive aspect. Like "Coop-etition", a portmanteau of Cooperation-Competition.

I'd read that because Japan is part of Artemis Program, as opposed to just Artemis Accords, then its upcoming joint mission with India for lunar surface exploration may supply Artemis Program partners with useful lunar data.

I'm not sure if it's Artemis which has also enabled Indian astronauts to fly to ISS? Or are these things not particularly related? I'd read that the flight could occur as part of the Axios set of missions which were already planned.
I'm wondering if any of this might pave the way for India's Gaganyaan capsule to one day dock with ISS?

For example, Arianne/ESA does not have any heavy lift capability left until Ariane 6 comes online and since Ariane 5 is now retired. Of course ESA will look at NASA and US private operators like SpaceX/Delta etc. Similarly the US operators both private and public will want additional payload capacity and similarly ISRO will want to use NASA deep space network etc. For example, once C3 makes it to Moon, ISRO will have two observation platforms plug'ed into ISRO's communication network that can help all future missions to moon (till of course the moon-sats retire).

Will CY-3 propulsion module stay in orbit around the Moon? Or will it be ditched? I'm assuming the former, since it has some SHAPE instrument onboard. And does it have the capacity to serve as a communication relay?

Yes, congratulations to them and a major achievement. We have been running around semi-cryo like a dog chasing its own tail since last 20 years. We developed and flew two seemingly more complex LOH-LOX cryo engine in that time. I say "seemingly", since it is complex, but in two decades we mastered two different cryo- stages (engines, stage, development flights, op flights, infrastructure) and the semi-cryo is still having hiccups on the test stand.

It was very evident, once we mastered cryo-, the next step would be to:

* look at similar cryo- like MethoLox OR not at all explore similar cryo but...
* ... scale up the existing ones.

Since Semi-cryo (with Isrosene etc) is a specialized process it was bound to have severe hurdles. The issue is not with technology, but with chemistry.

First we went through signing an agreement with Ukraine of all places, 2 decades back that too. That was wrong, because we were not going to get "technology transfer" and we already had a path into Cryo- via GSLV Mk1.

Then we went and signed a deal with Roscosmos. To test SCE200 in Russia while our own test stand was being built. Then we went back to Ukraine to test critical components.

In effect, ISRO was muddling around without a clear cut plan for the future. I can only say, let it muddle along SCE. That will be throwing good money behind bad instead of walking away from a bad investment.

Now news comes that ISRO has developed a metholox demonstrator engine of 200kN and plans to go for 5MN (5 Mega Newton) engine. And the 200kN came in record time. Why was this not picked up 10 years back? Even now they should go forward and operationalize the 200 kN metholox engine.

Anyway, from my perspective, ISRO must

* Develop 2-5 mN Metholox Engines
* Develop 70-140 kN variable thrust, 200 kN to 2-5 mN cryo- engines of various types, GG/Staged-Combustion/Expander etc.
* Restartable upto several times Metholox/Cryo- engines
* Reusable metholox/cryo- stages.
* Indian private sector can pick up small scale engines like metholox/LOH/LOX 2-5 kN restartable electric motor driven engines.

ISRO has the technical manpower and the budget to go full fledge on the above. Just get rid of the useless SCE program.

Once we have the engine building blocks and standardized (since its either LOH/LOX or LOX/CH4) engines and stages and the infrastructure to go for it, ISRO can start doing plug and play.

ISRO has already developed a remarkable lead in solid-boosters. So pairing with solid boosters with above building blocks on a "factory" mode will make India an unbeatable space power.

I'd really like to see us get to higher thrust engines, and deep throttling which is useful for powered landings.

Methalox will lower costs and simplify plumbing (phase temperature overlap between LCH4 and LOX) help reusability (single-carbon molecule reduces chances of polymerization/coking), and even enable potential return missions from Mars, if propellant can be regenerated there via Sabatier process.

I'd seen India researching scramjet propulsion, including for possible SSTO, but people tell me that scramjet is only good for long-distance cruising, and not so good for accelerating to orbital velocity, since it means a long ascent slough of pushing through the atmosphere instead of getting above it and avoiding atmospheric resistance. People seem to think that the mass-savings on oxidizer doesn't offset the burden/constraints of having to push through the atmosphere for nearly the entire ascent. Plus scramjet needs extra hardware of rockets to enable it, anyway.

[Ashokk]

Gaganyaan: Recovery trials enter phase-2 with harbour trials

BENGALURU: Recovery trial operations of the Gaganyaan mission entered the second phase with the commencement of harbor trials, Isro said on Saturday.

"The trials happened on July 20, at the Naval Dockyard, Visakhapatnam. ISRO and Indian Navy jointly carried out the trials with the ship identified for the recovery operations during the first development mission of the Test Vehicle," Isro said.
The trials were conducted at the Eastern Naval Command in Visakhapatnam, using a mass and shape simulated Crew Module Mockup (CMRM).
"This mockup was a crucial component in the testing process, ensuring that the recovery procedures accurately simulated conditions," Isro added.
The various stages of recovery were simulated during the trials, including the attachment of the recovery buoy, towing, handling, and lifting of the crew module onto the ship deck.
These procedures were executed according to the recovery sequence, demonstrating the preparedness of the teams involved, Isro said, adding that to ensure a seamless and safe recovery process, the Standard Operating Procedures (SOPs) were fine-tuned based on the experiences from the phase-1 trials at the Water Survival Training Facility (WSTF) in Kochi.

"This iterative approach allowed for refinements to be made, enhancing the efficiency and reliability of the recovery operations," Isro said.

[Roop]

... might pave the way for India's Gaganyaan capsule to one day dock with ISS?

Isn't the ISS going to be decommissioned in the next few years? I thought I read that somewhere.

[sanman]

... might pave the way for India's Gaganyaan capsule to one day dock with ISS?

Isn't the ISS going to be decommissioned in the next few years? I thought I read that somewhere.

According to NASA's own statements, ISS will be decommissioned and de-orbited by 2031. So that's another 7-8 years.
So there's a little bit of a window for us to fly and dock there, if we were all inclined towards this. Remember that China will be operating its own new version of ISS during this time. Pakistani & NorthKorean astronauts will likely be ferried to the station by China. Indian flights to ISS could at least provide us with a counterpoint (since we all know that we won't have any station of our own ready on a comparable timeframe.)

If SpaceX's new Starship vehicle becomes active before then, I bet the lifespan of ISS could easily be extended. Starship's cheaper lifting capacity and lower launch costs could easily improve the costs of ISS operation. In which case, why get rid of the station they took such pains to build? Maybe it could serve as a training facility for Zero-G and deep space missions, while also carrying out micro-gravity experiments.

[sanman]

Here's a re-post of an image I'd posted upthread -- CG rendered artwork showing India's Gaganyaan capsule preparing to dock with ISS:

Thought I'd just throw up this old CG-render someone made of Indian capsule approaching ISS:

https://www.deviantart.com/okan170/art/ ... -526254860

[Ashokk]

ISRO to launch PSLV-C56 carrying Singapore’s DS-SAR and six other satellites on July 30

The Indian Space Research Organisation (ISRO) on July 24 announced that the launch of the PSLV-C56 carrying Singapore’s DS-SAR satellite will take place on July 30.

The PSLV-C56 carrying DS-SAR satellite along with six co-passengers will be launched from the Satish Dhawan Space Centre in Sriharikota at 6:30 a.m. on July 30.

According to ISRO the PSLV-C56 is configured in its core-alone mode, similar to that of C55. It would launch DS-SAR, a 360 kg satellite into a Near-equatorial Orbit (NEO) at 5 degrees inclination and 535 km altitude.

The space agency added that the DS-SAR satellite is developed under a partnership between DSTA (representing the Government of Singapore) and ST Engineering.

Once deployed and operational, it will be used to support the satellite imagery requirements of various agencies within the Government of Singapore. ST Engineering will use it for multi-modal and higher responsiveness imagery and geospatial services for their commercial customers.

DS-SAR carries a Synthetic Aperture Radar (SAR) payload developed by Israel Aerospace Industries (IAI). This allows the DS-SAR to provide for all-weather day and night coverage and is capable of imaging at 1m resolution at full polarimetry.

ISRO added that New Space India Limited (NSIL) has procured PSLV-C56 to deploy the DS-SAR satellite.

[ramana]

Nice description of the LVM-3 payload fairing zip tube. It's being called a bellows which it is not.
The two det-cords initiate and pressurize the rubber tube to push away the payload fairing halves and open up the payload.
The article has two spelling mistakes. Its pyrotechnic charge and Marman band.

https://mysuruinfrahub.com/mysurus-mypo ... d-fairing/



and

Detail B

[Ashokk]

Harbour trials for Crew Module Recovery commenced - SpokespersonNavy @indiannavy

Joint #IndianNavy-@isro team successfully undertook recovery trials of Crew Module onboard earmarked ship at #EasternNavalCommand, Visakhapatnam as preparatory activity for 1st test launch mission

[Ashokk]

ISRO Supports a space start-up's Rocket Engine Test

July 22, 2023

On July 21, 2023, ISRO demonstrated its commitment to fostering the space ecosystem in India by enabling a successful rocket-engine test conducted by Skyroot, a Hyderabad-based space start-up, at ISRO Propulsion Complex (IPRC) Mahendragiri. The test took place in the Liquid Thruster Test Facility (LTTF) in IPRC. The testing was enabled by IN-SPACe.

The test involved the Raman-II engine, which was designed by Skyroot to generate 820 N (Sea Level) and 1460 N (Vacuum) thrust, with a nominal chamber pressure of 8.5 bar absolute. The regeneratively cooled engine, manufactured through additive manufacturing techniques, utilizes Mono Methyl Hydrazine and Nitrogen Tetroxide as propellants. The 10-second duration test achieved the expected performance in terms of start transient, steady state, and shut-off. Skyroot intends to integrate the Raman-II engine into the fourth stage of its launch vehicle, Vikram-I.

The test facility systems demonstrated normal performance during the test, meeting the engine inlet conditions at T0. The instrumentation systems also performed as expected, further ensuring the accuracy and reliability of the test results.

[nitzter]

So there's a little bit of a window for us to fly and dock there, if we were all inclined towards this. Remember that China will be operating its own new version of ISS during this time. Pakistani & NorthKorean astronauts will likely be ferried to the station by China. Indian flights to ISS could at least provide us with a counterpoint (since we all know that we won't have any station of our own ready on a comparable timeframe.)

Inter-operability is a part of the Artemis accords. I believe we should make use of it as much as we can... Presence in ISS will bring quick experience-building on SOPs and challenges for the future manned missions or building one's own station/cycler.

We have had our astronauts trained in Russia already - they are providing valuable feedback for the simulators... An insight into the American facilities and processes would reinforce ISRO's goals of getting things right in their first attempt!

[mody]

Why are we still using maraging steel for the S200 solid rocket boosters? Can composite rocket motors be developed for the same? We have now have composite rocket motors for the Agni-5. If the S200 can be made with composites, the weight would reduce and the obvious benefit would be a higher payload capacity.

[sanman]

So there's a little bit of a window for us to fly and dock there, if we were all inclined towards this. Remember that China will be operating its own new version of ISS during this time. Pakistani & NorthKorean astronauts will likely be ferried to the station by China. Indian flights to ISS could at least provide us with a counterpoint (since we all know that we won't have any station of our own ready on a comparable timeframe.)

Inter-operability is a part of the Artemis accords. I believe we should make use of it as much as we can... Presence in ISS will bring quick experience-building on SOPs and challenges for the future manned missions or building one's own station/cycler.

We have had our astronauts trained in Russia already - they are providing valuable feedback for the simulators... An insight into the American facilities and processes would reinforce ISRO's goals of getting things right in their first attempt!

So our participation with ISS can be like how our experience-building thru INS Chakra helped us prepare for our own N-sub?

I wonder if we'll have another "Sare Jahaan Se Accha" PR quotation exercise from this?

I think it would be a nice gesture if an Indian capsule could dock with ISS -- although it would require extensive preparation, etc.

[Ashokk]

Gaganyaan Mission: Successful second and third Hot Test of Service Module Propulsion System

ISRO successfully carried out two more hot tests on the Gaganyaan Service Module Propulsion System (SMPS) at ISRO Propulsion Complex (IPRC), Mahendragiri on July 26, 2023. The SMPS is designed and developed by the Liquid Propulsion System Centre (LPSC) located at Bangalore and Valiamala, Thiruvananthapuram. These tests marked the second and third hot tests in the Service Module – System Demonstration model (SM-SDM) phase 2 test series. The first hot test was conducted on July 19, 2023.

During yesterday’s tests, the thrusters were operated in both continuous and pulse mode, in sync with the mission profile. The initial hot test which lasted for 723.6 s focussed on demonstrating Orbital Module injection and the calibration burn of 100 N thrusters and Liquid Apogee Motor (LAM) engines. The calibration burn was essential to identify and isolate any non-operational engines. The LAM engines and reaction control system (RCS) Thrusters performed as expected.

The latter hot test, with a duration of 350 s, aimed to demonstrate the circularization of the Orbital Module to achieve the final orbit. During this test, the LAM engines operated in continuous mode, while the RCS Thrusters fired in pulse mode.

Looking ahead, three more hot tests are scheduled to demonstrate de-boosting requirements and off-nominal mission scenarios. These tests will further validate and refine the performance of the propulsion system, ensuring its readiness for the upcoming Gaganyaan mission.

[Tanaji]

Why are we still using maraging steel for the S200 solid rocket boosters? Can composite rocket motors be developed for the same? We have now have composite rocket motors for the Agni-5. If the S200 can be made with composites, the weight would reduce and the obvious benefit would be a higher payload capacity.

In my opinion ISRO is optimising for costs rather than payload as they probably have a curve where it makes more sense to do so given the falling prices for payload in the launch market. SpaceX uses maraging steel as well.

Agni of course will prioritise payload/range over other factors.

[SSridhar]

In my opinion ISRO is optimising for costs rather than payload as they probably have a curve where it makes more sense to do so given the falling prices for payload in the launch market. SpaceX uses maraging steel as well.

Whatever it is, we have to think of booster reuse sooner than later to reduce costs even further.
SpaceX uses some kind of Aluminium alloy.

[nitzter]

Why are we still using maraging steel for the S200 solid rocket boosters? Can composite rocket motors be developed for the same? We have now have composite rocket motors for the Agni-5. If the S200 can be made with composites, the weight would reduce and the obvious benefit would be a higher payload capacity.

In my opinion ISRO is optimising for costs rather than payload as they probably have a curve where it makes more sense to do so given the falling prices for payload in the launch market. SpaceX uses maraging steel as well.

Agni of course will prioritise payload/range over other factors.

My initial thought was towards S200 chamber pressure of 56 bars and it's human rating... The lack of reading material on the Agni programme, for obvious reasons, will never let us know.

[nitzter]

So our participation with ISS can be like how our experience-building thru INS Chakra helped us prepare for our own N-sub?

I wonder if we'll have another "Sare Jahaan Se Accha" PR quotation exercise from this?

I think it would be a nice gesture if an Indian capsule could dock with ISS -- although it would require extensive preparation, etc.

PR and optics are very important to both governments. India would like to sent a citizen to space in view of the elections and USA would like to present a divide between us and the other BRICS nations (two of them being major space-farers).

We can forget about any tech transfer but experience can be shared and learnt... I presume there must be a push from the ISRO chief here as well, given his play safe/take solid steps approach.

NASA has openly published the docking specifications and all other ISS collaborators work on the same design. Its better to standardize these things for future proofing and emergency. Anyway, fingers crossed for the docking experiment next year...

[nitzter]

In my opinion ISRO is optimising for costs rather than payload as they probably have a curve where it makes more sense to do so given the falling prices for payload in the launch market. SpaceX uses maraging steel as well.

Whatever it is, we have to think of booster reuse sooner than later to reduce costs even further.
SpaceX uses some kind of Aluminium alloy.

I read that there were rigorous landing tests done on a CY3 prototype. That's a good precursor to resusability... Do you have any insight into that?

[Tanaji]

Whatever it is, we have to think of booster reuse sooner than later to reduce costs even further.
SpaceX uses some kind of Aluminium alloy.

SSridharji, I am on the fence about this. ISROs ambit or mission is to support India’s space requirements - be it satellites or launches. Commercial launches are an after thought. Yes, it makes a tidy side income with these launches, but that’s not the main purpose. This is opposed to SpaceX which is an out and out commercial venture that must make a profit and reduce costs.

I agree that booster reuse is required especially if we start making higher impulse engines. But is it as much a priority for ISRO given its budget constraints and other programs?