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Isro’s new GSLV Mk III rocket places GSAT-19 communication satellite in orbit (timesofindia.com)
274 points by dmingoddd on June 5, 2017 | hide | past | favorite | 51 comments


Some really nice photos of this on the ISRO site: http://www.isro.gov.in/gslv-mk-iii-d1-gsat-19-mission/gslv-m...

Also the launch video is amazing. The moment the engines ignite the whole thing is moving most likely because those are solid rocket boosters and there's no throttle up time: https://www.youtube.com/watch?v=ae6LVG0j1Pg


> https://www.youtube.com/watch?v=ae6LVG0j1Pg

The lift-off start position is at 3:45.


Yes. GSLV Mk III first stage is made up of two S200 solid boosters, with 200 ton propellant in each. S200 is the third largest solid boosters in the world (after Shuttle SRB, and P230 of Ariane-5).


If the figures at http://www.globalsecurity.org/space/systems/t4-config-5.htm are correct, the Titan IVB "SRM upgrade" boosters were bigger too (over 300 tonnes of propellant)


I don't know why the video quality is so shitty. My cellphone takes better quality footage than this. I would assume they could have used a tiny portion of their multi-million $ budget for some decent cameras.


Props to them for having old school, Apollo-style consoles in the mission control room. You loose something when you have youngsters with a bunch of Dell monitors like spaceX. I've seen twitch on the second monitor in spacex control room.


> You loose something when you have youngsters with a bunch of Dell monitors like spaceX.

What, exactly, do you lose?


Vaguely worded nostalgia


zing


Yeah, imagine what they could do if they had dell monitors. I bet spacex wouldn't stand a chance.


Congratulations ISRO.. Good step in right direction.

If we compare this to current SpaceX Falcon 9 (not Falcon Heavy ) http://www.spacex.com/falcon9

Falcon 9 can deliver 8300 Kg to GTO and 22,800kg to LEO.

GSLV MK III delivers 4000 Kg to GTO and 8000KG to LEO ( http://www.isro.gov.in/launchers/gslv-mk-iii )

Mr. Musk will be delivering hell lot of stuff to space with his reusable rockets. SO, he will be very cost competitive to ISRO w.r.t launch price.


Falcon 9 FT beats Mk III hands down.

But ISRO reached 2 Tons for GSLV just last year, This is rated at 4 Tons, and future improvements to 8 to 10 tons is on cards within 1-2 years. Even a proposal for 15 Tons by 2020.

http://www.thehindu.com/news/national/Mega-launchers-for-ISR... (https://en.wikipedia.org/wiki/SCE-200)


The ISRO is pegging the price at Rs 400 Cr which is almost identical to a Falcon 9 at $62M at current exchange rates. Falcon 9 appears to win on price/payload, but ISRO is in the ballpark, impressive.


Except ISRO's margin can't be as good on the materials (although it's probably better on the staff costs). Th F9 FT has a take off mass of 549 metric tons and can put just under 23 metric tons into LEO, the GSLV-III has a mass of 640 metric tons and can put 10 metric tons into LEO. The combined propellent mass for the F9FT is approx 508 metric tons, the GSLV-III is 554 metric tons. So the non propellent mass for the F9FT is 41 metric tons, and the GSLV-III is 86 metric tons. What's more I'm fairly certain that the solid booster propellent costs more per ton, they are much much simpler to manufacture than liquid fuelled engines. F9 however is reusable and is almost completely assembled if not manufactured in house.

So I strongly suspect that SpaceX's margins are much better than ISRO's and that the development costs have been viewed as sunk cost by the Indian government.

Still it is a huge (100% plus) leap for ISRO; I'm sure as they launch more as well as more often their costs and mass fractions will improve.


good analysis, but i think you're missing the fact that the upper stage has a hydrolox engine, which destroys the falcon 9 stage 2 in terms of Isp (wikipedia gives 443 s). i wouldn't be surprised if it can carry more to geo-1500 than the f9.

edit: well the same wikipedia cites 4000kg to GTO so my guess is wrong.


Isp is only one factor. The GSLV Mk. 3's upper stage is LOX/LH2 but it's also fairly small. The Falcon 9's upper stage is 4 tonnes empty 107.5 tonnes fueled, with an Isp of 348s. The GSLV Mk. 3's upper stage has an Isp of 443s (good) a dry mass of 5 tonnes (not as good) and a wet mass of 33 tonnes. The mass fraction on the F9 upper stage utterly dominates the GSLV's upper stage Isp.

Let's look at GTO payloads and upper stage delta V.

GSLV Mk. 3: 4 tonnes, which translates to a stage delta V of ln((4+33)/(4+5)) x 4.34km/s = 6.135 km/s

F9 FT: 8.3 tonnes -> ln((8+107.5)/(8+4)) x 3.41 = 7.72 km/s

So the Falcon 9's upper stage is able to push twice as heavy a payload through about 1.6 km/s more delta V despite having nearly a full km/s lower exhaust velocity, all because it has a better mass ratio.


thanks for the writeup!


I would be esctatic if ISRO just breaks even..It's not about margins. Just Imagine the fact NASA or ISRO does not need to depend on Govt and they generating their own money and continuing their research without interruptions.

No Tax payer money going to them and don't need to depend on Congress/Senate/President/ Prime minister mood to fund them.

Where as Musk, he is a private entrepreneur. He is upping the space game like anything.


GSLV Mk III is a brand new launch vehicle. Usually, ISRO starts with conservative payload numbers for all their launch vehicles, and keep improving them iteratively. We have seen this happening with PSLV and GSLV Mk II as well. We can expect ISRO to bump up GSLV Mk III payload capacity in subsequent launches.


I'm not doubting whether ISRO will reach the weight range or not. It is how quickly they can reach in par with falcon 9.

As the payload doubles from 4000KG to 8000KG (to be in par with Falcon 9 ), You need to add more fuel and which increases the cost and total weightage of the rocket.

This additional weightage on the rocket will hamper the margins.

I'm not saying anything negative here and they have lot of work cut out for them because of re-usability of Falcon 9.

Overall, this is very good for us as competition drives the cost down and more and more services at lower cost.

Good positive start.


Actually having a higher percentage of mass for your propellant (fuel and oxidiser) compared to your total mass (minus payload which can vary flight to flight) is a good thing; it means you can deliver more mass to orbit. [0] Conversely the more mass you use to build your rocket the less mass you can deliver to orbit. For the F9FT the propellant mass fraction is 92.43% (507.5/549), and for the GSLV-III it is 86.56% (544/640). [1][2] If the GSLV-III had the same PMF as the F9FT its dry weight would drop from 86 tons to 45.5 tons. Then it would probably be able to deliver 25 to 26 tons to LEO, an increase of 2.5 times.

I'm sure the ISRO will improve the mass fraction over time. It should be noted however that the F9 with all its single core iterations have been within 1% of each other propellant mass fraction wise.

[0] https://en.wikipedia.org/wiki/Propellant_mass_fraction

[1] https://www.reddit.com/r/spacex/comments/3lsm0q/f9ft_vs_f9v1...

[2] https://en.wikipedia.org/wiki/Geosynchronous_Satellite_Launc...

[EDIT] minor grammar fix


For comparison, expendable payload of Falcon 9 more than doubled between the first launch and the current version. (Reusable payload of the current version is less, but still exceeds the expendable payload of the original Falcon 9 1.0.) That Falcon 9 increase includes the significant engine upgrade to Merlin-1D, but ISRO is already planning to replace the core stage of its GPSV with a larger stage taking different fuels, which should boost capability significantly.


Yes, and I think the ISRO has great vision for the future; its second stage engine is its first truly home grown engine and it performed admirably. Once it gets its own home designed and built engine to replace the Vikas (which is based on the French Viking 4A engine from the 70s) it will greatly boost the GSLV's lift capability.


> http://www.spacex.com/falcon9

According to the technical overview, Falcon 9 can also deliver 4020 kg to Mars :)


To put that into perspective, India's last Mars satellite https://en.wikipedia.org/wiki/Mars_Orbiter_Mission weighed 1.3 metric tons, and was launched on PSLV-XL.


Thanks for the wiki. ISRO has been consistently performing well. They can be a role model for other government agencies in India.


Hmm this is weird. The description says "about 10 tons to Low Earth Orbit (LEO)" but the technical specification says "8000KG".


10 [US] tons = ~9000 kg


I am pretty sure ton in India means metric ton, not [US] ton.


8 tons to GTO is the expendable weight limit. With reuse it is around 5.5 tons.


GSAT-19 satellite also has electrical propulsion system[1] along with the regular hypergolic motors. ISRO is validating their Hall effect electrical propulsion systems for north-south station keeping[2]. Going forward, electrical propulsion systems will greatly reduce the amount of fuel that need to be carried in satellite.

[1] http://economictimes.indiatimes.com/news/science/india-to-av...

[2] https://forum.nasaspaceflight.com/index.php?topic=33770.0


This is an important milestone for ISRO. This launch successfully validated ISRO's homegrown CE-20[1] gas generator cycle cryogenic engine. With this, ISRO has mastered both staged combustion (CE-7.5[2]) and gas generator cycle cryogenic engine technologies.

Next up is SCE-200 RP-LOX engine[3]! There is a plan to swap GSLV Mk III's L110 hyperglic stage with SCE-200 stage, which should considerably boost payload capacity.

[1]https://en.wikipedia.org/wiki/CE-20

[2]https://en.wikipedia.org/wiki/CE-7.5

[3]https://en.wikipedia.org/wiki/SCE-200


The title says nothing, especially given ISRO's track record. The big news is about the launch vehicle - GSLV Mk III - the most powerful rocket from ISRO.


Doubling the payload to orbit to 10 metric tons and reducing the use of hydrozine to one stage are both big improvements.


and the one that has potential to take an Indian to the moon.


With capacity of 10 tons to LEO, 4 tons to GTO, it's somewhere between the Titan II (used for Gemini) and Titan III.

Would have to be a pretty lean moon mission.


Only for a direct ascent architecture. There are lots of Earth orbit assembly missions that would be possible and not terribly expensive to pull off (at least for a lunar flyby style mission).


Wouldn't be a manned mission, but that's plenty enough for a small rover mission.


This is a big deal for ISRO when it becomes operational. In terms of launching its own heavy communication satellites, it doesn't have to rely on the Ariane. I can see a lot of customers queuing up to Antrix to launch commercial satellites. One can hope it eats into SpaceX's lunch in the near future.


The last 2 Indian satellites launched on Ariane V fit on this new rocket (~3.2 metric tons), but, that's a medium-sized satellite. Ariane V usually launches pairs of satellites, one ~ 3mt and one ~ 6mt.

As for price, surfing the Internets I see Rs 350 to Rs400 crore as a price, which ~ $56-$64 million dollars. SpaceX's price for a "flight proven" GTO launch is supposedly $62 million less 10%, or about the same.


GSLV MK3 is a crucial enabling technology for future applications for ISRO. They plan to human certify it. But most importantly, it's planned to evolve into new family of launch vehicles called Unified Launch Vehicle (ULV). A new SCE-200 semi-cryogenic engine which is under development and other upgrades could enhance the payload capacity to 6 metric tons. So the ULV will eventually replace PSLV and the GSLV MK2.

As for pricing, I definitely agree SpaceX has the edge especially with their reusable rockets. But one can still hope ISRO catches up :)


More about the launch vehicle:

http://isro.gov.in/launchers/gslv-mk-iii


The current title here "ISRO places communication satellite in orbit" buries the lede -- the big deal is this new launch vehicle, which has 2X the payload of India's GSLV mark II.


Thanks, we've updated the title (which was likely edited for space) to include this.


I agree, it's a three-stage heavy lift launch vehicle with a mass of 640 tonnes.


Did I miss something here?

The rocket is nicknamed "fatboy" and it is indeed fat. I was having the impression that india finally made a rocket comparable to Falcon Heavy, Ariane 5, Delta IV Heavy and CZ-5. When I checked its specs, well, 8,000kg to LEO and 4,000kg to GTO, seriously? Not trying to discount its symbolic importance to india, but technically, why its so fat when the payload capacity is so limited?


The Falcon 9 is long and thin, this one is short and stout, and they weight about the same amount. The payload isn't nearly as good as the current Falcon 9 revision but it's about the same as the Falcon 9 v1.0 from way back in 2010 and most rockets of similar. The payload to mass isn't great compared to other rockets but most of the gross mass is in the solid boosters so you shouldn't expect the price to be very high for the mass to orbit.


Using wikipedia data, Falcon 9 has 20% less weight when it is in the reusable mode, at the same time its LEO/GTO payload capacity is better. I don't think those two are on the same level, Falcon 9 is THE state of the art while GSLV MKIII is just a highly inefficient rocket with some pretty poor specs.


Here is the full launch video:

https://youtu.be/ae6LVG0j1Pg?t=202



Great Post on Quora by a ISRO engineer on the significance of GSLV to ISRO: https://www.quora.com/What-does-the-GSLV-MK-III-mean-to-ISRO...




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