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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
Earlier quoted context omitted.
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…
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
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
Earlier quoted context omitted.
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…
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 fu…
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
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.
What, exactly, do you lose?
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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?
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 comp…
[1] http://economictimes.indiatimes.com/news/science/india-to-av...
[2] https://forum.nasaspaceflight.com/index.php?topic=33770.0
Earlier quoted context omitted.
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…
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.
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.