GSLV-Mk III launch program/post-launch analysis
Re: GSLV-Mk III launch program/post-launch analysis
the 4 lattice towers around the pad have boxes on each floor. are they cameras and sensors?
i assume they also act as lightning rods.
i assume they also act as lightning rods.
Re: GSLV-Mk III launch program/post-launch analysis
Fantastic job ISRO. Truly a crown jewel among the PSU/Govt Owned institutions. Speaks to the importance of great leadership in succession, a highly motivated team and great culture, teamwork. This is true mastery of rocket science on shoe string budget in the face of technology denial regimes - mission to moon, mars and 10's of consecutive successful launches of PSLV and now CUS success in the first launch.
I recall Mr. Al Gore (then VP of U.S) personally lobbied the post soviet Russia to not transfer Cryogenic engine technology and limited it instead to the transfer of a few fully assembled engines. Well it took a couple of decades but all the derivative technologies that ISRO and the private sector that worked on this major achievement have realized is hugely valuable in the long run. Thanks to the sanctions regime.
Let us not forget the 10,000 KG (10 tons) to Low Earth/Polar orbit capability with this rocket. Should enable ISRO to hurl huge special mission imaging satellites similar in size to Key Hole family. 16Tons to LEO with the future GSLV Mark 4. That is some serious horsepower.
The nation owes a huge debt of gratitude to ISRO.
I recall Mr. Al Gore (then VP of U.S) personally lobbied the post soviet Russia to not transfer Cryogenic engine technology and limited it instead to the transfer of a few fully assembled engines. Well it took a couple of decades but all the derivative technologies that ISRO and the private sector that worked on this major achievement have realized is hugely valuable in the long run. Thanks to the sanctions regime.
Let us not forget the 10,000 KG (10 tons) to Low Earth/Polar orbit capability with this rocket. Should enable ISRO to hurl huge special mission imaging satellites similar in size to Key Hole family. 16Tons to LEO with the future GSLV Mark 4. That is some serious horsepower.
The nation owes a huge debt of gratitude to ISRO.
Re: GSLV-Mk III launch program/post-launch analysis
can anyone explain this technology? how do you propel in space using electric power not involving rockets or cold gas?
We have a six-tonne satellite in principle. It is possible to be realised using electric propulsion. So we have already started using electric propulsion system. (Even) GSAT-19 (launched today) carries an electric propulsion system. So, we have successfully tested that," he said.
We have a six-tonne satellite in principle. It is possible to be realised using electric propulsion. So we have already started using electric propulsion system. (Even) GSAT-19 (launched today) carries an electric propulsion system. So, we have successfully tested that," he said.
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Re: GSLV-Mk III launch program/post-launch analysis
What was the actual apogee and perigee as compared to the expected value? Looked at ISRO website press release, but there is no info on that.
Re: GSLV-Mk III launch program/post-launch analysis
Ion ThrusterSingha wrote:can anyone explain this technology? how do you propel in space using electric power not involving rockets or cold gas?
https://en.wikipedia.org/wiki/Ion_thruster
Re: GSLV-Mk III launch program/post-launch analysis
Bingo,,,,,,,,,,, I got it first...
http://pib.nic.in/newsite/PrintRelease. ... lid=164422
Press Information Bureau
Government of India
Department of Space
05-June-2017 20:15 IST
First Developmental Flight of India's GSLV Mk III Successfully launches GSAT-19 Satellite
The first developmental flight (GSLV MkIII-D1) of India's heavy lift launch vehicle GSLV Mk-III was successfully conducted today (June 05, 2017) evening from Satish Dhawan Space Centre SHAR, Sriharikota with the launch of GSAT-19 satellite. This was the first orbital mission of GSLV MkIII which was mainly intended to evaluate the vehicle performance including that of its fully indigenous cryogenic upper stage during the flight. Weighing 3136 kg at lift-off, GSAT-19 is the heaviest satellite launched from the Indian soil.
After a twenty five and a half hour smooth countdown, the mission began with the launch of the 640 ton GSLV Mk-III at 5:28 pm IST from the Second Launch Pad as scheduled with the ignition of its two S200 solid strap-on boosters. Following this, the major phases of the flight occurred as scheduled. The upper stage of GSLV MkIII vehicle is a new cryogenic stage (C25) indigenously configured, designed and realised by ISRO. The cryogenic stage used liquid Hydrogen and liquid Oxygen as propellants with a total loading of 28 tons. The stage is powered by a 20 ton thrust cryogenic engine (CE20) operating on ‘gas generator cycle’. The performance of the engine and stage during the mission was as predicted. About sixteen minutes after lift-off, GSAT-19 satellite was successfully placed in orbit.
Soon after its separation from GSLV, the Master Control Facility (MCF) at Hassan in Karnataka assumed control of the satellite. GSAT-19 is a high throughput communication satellite.
In the coming days, GSAT-19 orbit will be raised from its present Geosynchronous Transfer Orbit (GTO) to the final circular Geostationary Orbit (GSO) by firing the satellite's Liquid Apogee Motor (LAM) in stages. During the final phase of this operation, the solar panels and antenna reflectors of the satellite will be deployed. The satellite will be commissioned into service after its positioning in the designated slot in the GSO following in-orbit testing of its payloads.
____________
KSD/NK/KM
http://pib.nic.in/newsite/PrintRelease. ... lid=164422
Press Information Bureau
Government of India
Department of Space
05-June-2017 20:15 IST
First Developmental Flight of India's GSLV Mk III Successfully launches GSAT-19 Satellite
The first developmental flight (GSLV MkIII-D1) of India's heavy lift launch vehicle GSLV Mk-III was successfully conducted today (June 05, 2017) evening from Satish Dhawan Space Centre SHAR, Sriharikota with the launch of GSAT-19 satellite. This was the first orbital mission of GSLV MkIII which was mainly intended to evaluate the vehicle performance including that of its fully indigenous cryogenic upper stage during the flight. Weighing 3136 kg at lift-off, GSAT-19 is the heaviest satellite launched from the Indian soil.
After a twenty five and a half hour smooth countdown, the mission began with the launch of the 640 ton GSLV Mk-III at 5:28 pm IST from the Second Launch Pad as scheduled with the ignition of its two S200 solid strap-on boosters. Following this, the major phases of the flight occurred as scheduled. The upper stage of GSLV MkIII vehicle is a new cryogenic stage (C25) indigenously configured, designed and realised by ISRO. The cryogenic stage used liquid Hydrogen and liquid Oxygen as propellants with a total loading of 28 tons. The stage is powered by a 20 ton thrust cryogenic engine (CE20) operating on ‘gas generator cycle’. The performance of the engine and stage during the mission was as predicted. About sixteen minutes after lift-off, GSAT-19 satellite was successfully placed in orbit.
Soon after its separation from GSLV, the Master Control Facility (MCF) at Hassan in Karnataka assumed control of the satellite. GSAT-19 is a high throughput communication satellite.
In the coming days, GSAT-19 orbit will be raised from its present Geosynchronous Transfer Orbit (GTO) to the final circular Geostationary Orbit (GSO) by firing the satellite's Liquid Apogee Motor (LAM) in stages. During the final phase of this operation, the solar panels and antenna reflectors of the satellite will be deployed. The satellite will be commissioned into service after its positioning in the designated slot in the GSO following in-orbit testing of its payloads.
____________
KSD/NK/KM
Re: GSLV-Mk III launch program/post-launch analysis
Owners Pride , Neighbours Envy .....Takleef for UK
'Fat boy' flies: ISRO's heavy rocket fails to blow up
https://www.theregister.co.uk/2017/06/0 ... o_blow_up/
'Fat boy' flies: ISRO's heavy rocket fails to blow up
https://www.theregister.co.uk/2017/06/0 ... o_blow_up/
Re: GSLV-Mk III launch program/post-launch analysis
I have to blame ISRO for turning success into such a routine that even history defining moments have been turned into boring deja vu. My guess is that the configuration of GSLV Mark3 will continue to improve (even without SCE) to 6 tons GTO. Add electric engines to Satellites, we will be putting into orbit an equivalent of 10 tons Satellite with Mk-3 alone.
Re: GSLV-Mk III launch program/post-launch analysis
^^ the deadpan guy with the 'cryo performance naarmal' took all the white knuckle drama out of it.
the comments as usual make my day
http://www.dailymail.co.uk/sciencetech/ ... orbit.html
the comments as usual make my day
http://www.dailymail.co.uk/sciencetech/ ... orbit.html
Re: GSLV-Mk III launch program/post-launch analysis
Be grateful, without brit aid money, we couldn't have come this far, let alone have space program.
Re: GSLV-Mk III launch program/post-launch analysis
i looked up list of intelsat sats, which is 50+.
they seem to be of 2 heavy types. one is 3.5t and the other is 6.5t
look up the 29e specs - 15 yrs life, 6.5t and high throughput for tv work...thats about the biggest civilian payload at present. i have a feeling its unlikely to grow much larger...tv being a bcast is inherently very efficient
https://en.wikipedia.org/wiki/List_of_I ... ce_2009.29
if we can realize a ULV that can loft 8t to GTO and say 15t to LEO, that will cover all our heavy needs perfectly.
and the current mk3 gslv can after qualification handle these 3.5t medium heavy 2nd tier of comm sats.
mk2 gslv can lift most of our polar orbital spy and commsats perhaps upto 8t into LEO-MEO orbits...with the mk3 as backup on heavier side of spectrum. multiple IRNSS , cartosat and Ofek sats for example in single mission.
the ULV could pitch in for the rare "keyhole" type of payload that is high weight + high volume being a optical telescope with massive orbit correction fuel ... and Soyuz-Dragon type spacefaring human modules.
we are probably 5 yrs out from ULV 1st flight and 8 yrs from IOC. .... mashallah by 2025 it will be done deal and advances in optics and electronics will gate the size of payload.
they seem to be of 2 heavy types. one is 3.5t and the other is 6.5t
look up the 29e specs - 15 yrs life, 6.5t and high throughput for tv work...thats about the biggest civilian payload at present. i have a feeling its unlikely to grow much larger...tv being a bcast is inherently very efficient
https://en.wikipedia.org/wiki/List_of_I ... ce_2009.29
if we can realize a ULV that can loft 8t to GTO and say 15t to LEO, that will cover all our heavy needs perfectly.
and the current mk3 gslv can after qualification handle these 3.5t medium heavy 2nd tier of comm sats.
mk2 gslv can lift most of our polar orbital spy and commsats perhaps upto 8t into LEO-MEO orbits...with the mk3 as backup on heavier side of spectrum. multiple IRNSS , cartosat and Ofek sats for example in single mission.
the ULV could pitch in for the rare "keyhole" type of payload that is high weight + high volume being a optical telescope with massive orbit correction fuel ... and Soyuz-Dragon type spacefaring human modules.
we are probably 5 yrs out from ULV 1st flight and 8 yrs from IOC. .... mashallah by 2025 it will be done deal and advances in optics and electronics will gate the size of payload.
Re: GSLV-Mk III launch program/post-launch analysis
the most large satellite ever launcher into GTO is the terrestar-1 which is 6.9 tons
https://en.wikipedia.org/wiki/TerreStar-1
so all the talk of even 8t to GTO being "weak" is hogwash. the only reasonable user cases beyond that are huge ISS / Dragon type modules and space telescope type billion $$ plays.
for that adding 2 more strap ons to a 1 core + 2 strap on design is probably best route than developing a new uber behemoth Energia type rocket that will get used once in 2 yrs.
https://en.wikipedia.org/wiki/TerreStar-1
so all the talk of even 8t to GTO being "weak" is hogwash. the only reasonable user cases beyond that are huge ISS / Dragon type modules and space telescope type billion $$ plays.
for that adding 2 more strap ons to a 1 core + 2 strap on design is probably best route than developing a new uber behemoth Energia type rocket that will get used once in 2 yrs.
Re: GSLV-Mk III launch program/post-launch analysis
Hubble was 12 tons to Leo. If we are planning to have a telescope with similar capabilities maybe a bit lighter with ion propulsion, then 15t to Leo with a ULV sounds good.
Re: GSLV-Mk III launch program/post-launch analysis
thats the very outer end of our use case. we are 10 yrs away from being able to build such payloads maybe. our ground based telescopes seem to lag far behind the edge in terms of mirror diameter ? in radio astronomy we may be closer to world stds.
Re: GSLV-Mk III launch program/post-launch analysis
Why do payloads have to get heavier and not lighter. Why would a cluster of 500 kg satellites on Geosynchronous orbit not do the work of one humongous satellite? When it comes to destroying sat capability (or failures) it would make sense to have a swarm rather than one no? I can see"cost of launch" as a barrier - but would 2 x GSLV mk 3s carrying 8 x 500 kg sats be more expensive than one 8 ton launch by Ariane? Cost also needs to be looked at in the context of whose salaries are being paid by the launch no?
Re: GSLV-Mk III launch program/post-launch analysis
Sum of parts is not the same. Payload is sacrificed as you need to duplicate propulsion, solar power generating modules, data bus, communication equipment, etc, across all those mini-sats.shiv wrote:Why do payloads have to get heavier and not lighter. Why would a cluster of 500 kg satellites on Geosynchronous orbit not do the work of one humongous satellite? When it comes to destroying sat capability (or failures) it would make sense to have a swarm rather than one no? I can see"cost of launch" as a barrier - but would 2 x GSLV mk 3s carrying 8 x 500 kg sats be more expensive than one 8 ton launch by Ariane? Cost also needs to be looked at in the context of whose salaries are being paid by the launch no?
Re: GSLV-Mk III launch program/post-launch analysis
Current commercial satellites won't require anything more than the Mk3 with the semi cryo stage. Should be price competitive with Ariane and the Russians too. Future satellites like OneWeb and SpaceX internet constellation may not be feasible without reusability.
Re: GSLV-Mk III launch program/post-launch analysis
I hope ISRO speeds up MK3 iteration and hand it over to a Indian private companies. These companies can then drive down cost.
ISRO can then concentrate on TFTA techs like TSTO, hypersonic etc.We need to take the wind out of US, Russian, Chinese space startups.
ISRO can then concentrate on TFTA techs like TSTO, hypersonic etc.We need to take the wind out of US, Russian, Chinese space startups.
Re: GSLV-Mk III launch program/post-launch analysis
I wonder whether ISRO thought about doing an experiment with restarting the cryo stage in space after its job was done. We do need to develop restart capability for the future.
Re: GSLV-Mk III launch program/post-launch analysis
Just a naive question- do we salvage our boosters?
Re: GSLV-Mk III launch program/post-launch analysis
One 12-seater van versus four 3-seater auto. Both carry 12 passengers, they have the propulsion etc. They have the pros and cons, no?JTull wrote:Sum of parts is not the same. Payload is sacrificed as you need to duplicate propulsion, solar power generating modules, data bus, communication equipment, etc, across all those mini-sats.shiv wrote:Why do payloads have to get heavier and not lighter. Why would a cluster of 500 kg satellites on Geosynchronous orbit not do the work of one humongous satellite? When it comes to destroying sat capability (or failures) it would make sense to have a swarm rather than one no? I can see"cost of launch" as a barrier - but would 2 x GSLV mk 3s carrying 8 x 500 kg sats be more expensive than one 8 ton launch by Ariane? Cost also needs to be looked at in the context of whose salaries are being paid by the launch no?
Re: GSLV-Mk III launch program/post-launch analysis
PSLV is prime example of payloads getting lighter and not requiring 2 tons to SSO capability.
Re: GSLV-Mk III launch program/post-launch analysis
Singha, google and read about Boeing all electric satellites. You will get a good idea about ion engines & their impact.Singha wrote:can anyone explain this technology? how do you propel in space using electric power not involving rockets or cold gas?
We have a six-tonne satellite in principle. It is possible to be realised using electric propulsion. So we have already started using electric propulsion system. (Even) GSAT-19 (launched today) carries an electric propulsion system. So, we have successfully tested that," he said.
Re: GSLV-Mk III launch program/post-launch analysis
Agreed - but even if you have 2 x 4 tonners rather than one 8 tonner - all the extra money will be spent in India paying Indians rather than paying Ariane to launch an 8 tonner.JTull wrote: Sum of parts is not the same. Payload is sacrificed as you need to duplicate propulsion, solar power generating modules, data bus, communication equipment, etc, across all those mini-sats.
Why should payload weights keep on going up and up and up. When we had 1 ton Ariane had 4. We have 4 now - they have 8-10. Must we chase that? There has to be some practicable limit. After all - orbiting space stations are built from joining up bits and pieces. Let there be more launches as long as the money is spent in India on Indian workers
Re: GSLV-Mk III launch program/post-launch analysis
If America wants - I am certain that they can get parts of their space stuff and war machines manufactured cheaper from China or elsewhere. In fact they got workers and software people cheap for 20 years. Now Trump says balls. Pay more & let Americans do it. Why can't we do that. Reusable may be cheaper but it is like import of F-16. Launching 1x8 ton sat for Ariane is like Rafale import. We can make 2 LCA here. Launch 2 x 4 tonners and pay Indians. Even if it is more costly the money goes to our people
Last edited by shiv on 06 Jun 2017 20:09, edited 1 time in total.
Re: GSLV-Mk III launch program/post-launch analysis
This is another nice article on electric propulsion experiments NASA is funding:Singha wrote:can anyone explain this technology? how do you propel in space using electric power not involving rockets or cold gas?
We have a six-tonne satellite in principle. It is possible to be realised using electric propulsion. So we have already started using electric propulsion system. (Even) GSAT-19 (launched today) carries an electric propulsion system. So, we have successfully tested that," he said.
https://arstechnica.com/science/2017/02 ... o-pay-off/
Re: GSLV-Mk III launch program/post-launch analysis
Crowd counting 6,5,4,3,2,1 and then majestic rocket. kya khub.Atmavik wrote:^^^ WOW. Thanks for sharing. heard "Bharat Mata Ki JAI"
Re: GSLV-Mk III launch program/post-launch analysis
Nice video.
To me it appears that an explosive separates the bolts that hold the solid boosters - some debris can be seen coming off (at 1 min 27sec) . But after separation the boosters move away slowly even as they are still breathing fire - and flame of the same colour can be seen from 3 jets emerging from the side of each booster (seen clearly from 1 min 34 sec) - which look like rockets to separate the boosters and move them away.
The kwoschun is this. Are these triple flames small thrusters or does the explosive simply punch holes in the side of the boosters and the same gas that is coming from the musharraf also vented from the side - helping to push the boosters away?
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Re: GSLV-Mk III launch program/post-launch analysis
Electric propulsion could mostly point to some kind of ion thruster , basically using electric fields to cause a electrode to emit ions with enough throughput to generate a significant impulse in low gravity conditions. Amreeka and Roos have used this in almost all of their interplanetary missions.
Re: GSLV-Mk III launch program/post-launch analysis
but arent ion thrusters very slow to pick up speed?
Re: GSLV-Mk III launch program/post-launch analysis
Constant slow acceleration using a small force - as one link said - using an ion thruster would speed a car up from zero to traffic highway speed in 2 months. But the same acceleration for a year would take it up to very high speeds. To change a satellite's position - maybe an ion thruster will be fired for 6 hours causing a very slow change of direction.Singha wrote:but arent ion thrusters very slow to pick up speed?
Re: GSLV-Mk III launch program/post-launch analysis
I think these are separate banks of three thrusters to pull the booster away.The kwoschun is this. Are these triple flames small thrusters or does the explosive simply punch holes in the side of the boosters and the same gas that is coming from the musharraf also vented from the side - helping to push the boosters away?
Punching holes via shaped charge is feasible but not reliable as the cut could vary.
If you notice these side firing thrusters tip the booster away after separation bolts are activated.
Flame color is same as propellant is same.
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Re: GSLV-Mk III launch program/post-launch analysis
There are explosive bolts used to separate the boosters and SRB separation event is a big piece of analysis(the boosters should fall away in an arc without colliding with the main rocket etc etc. Small vernier thrusters are used to guide the booster away
Last edited by prasannasimha on 06 Jun 2017 22:24, edited 1 time in total.
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Re: GSLV-Mk III launch program/post-launch analysis
They are relevant only in deep space or when limited to housekeeping activities or orbit change maneuvers . I forget the Nasa's probe which even used a solar sail to travel across our solar system . The there were old Roosi probes which even used nuclear power sources to power the ion thrusters like the Cosmos series.Singha wrote:but arent ion thrusters very slow to pick up speed?
Re: GSLV-Mk III launch program/post-launch analysis
There are actually not three, but six thrusters on each S-200 that are fired after separation. Three near the top of the booster, and three near the bottom.
Shiv: there are use cases for both large and small satellites. Not complete substitutes for each other. When the power requirements on the satellite are high, you have to have a large satellite with large solar panels to support the power requirements. In other instances, an array of smaller satellites might do. Also, a large array of smaller satellites in lower orbits might do what a large satellite in a higher orbit might do.
Shiv: there are use cases for both large and small satellites. Not complete substitutes for each other. When the power requirements on the satellite are high, you have to have a large satellite with large solar panels to support the power requirements. In other instances, an array of smaller satellites might do. Also, a large array of smaller satellites in lower orbits might do what a large satellite in a higher orbit might do.
Re: GSLV-Mk III launch program/post-launch analysis
The early 1990s were agonizing. ISRO basically put out a tender for supply of cryogenic engines with ToT before the 1992 US elections. General Dynamics (GD) offered the Atlas Centaur rocket without ToT for a large sum. Same with Ariane for their cryo-engine.Manas wrote:Fantastic job ISRO. Truly a crown jewel among the PSU/Govt Owned institutions. Speaks to the importance of great leadership in succession, a highly motivated team and great culture, teamwork. This is true mastery of rocket science on shoe string budget in the face of technology denial regimes - mission to moon, mars and 10's of consecutive successful launches of PSLV and now CUS success in the first launch.
I recall Mr. Al Gore (then VP of U.S) personally lobbied the post soviet Russia to not transfer Cryogenic engine technology and limited it instead to the transfer of a few fully assembled engines. Well it took a couple of decades but all the derivative technologies that ISRO and the private sector that worked on this major achievement have realized is hugely valuable in the long run. Thanks to the sanctions regime.
.....
The nation owes a huge debt of gratitude to ISRO.
The Russians offered a half developed cryo-engine and ToT. At that time Boris Yeltsin was in charge of CIS as FSU was initially called. His Foreign Minister was Andrei Kozyrev. Both these very pliable 'leaders' and Al Gore left nothing to chance. First they drummed up false charges of ICBM development by India and the potential use of this cryo-engine for that and demanded CIS cancel the deal despite the fact that both GD and Ariane had bid for the contract and were overpriced and nudged out. And it was a US company that built the liquid Hydrogen fuel plant! But India had already paid the money to FSU. Hence the deal was re-structured for 7 cryo-engines* and 2 dummies for engineering mockups for the same money. The money was used to develop the Russian cryo-engine which was non-existent.
Along the way, ISRO developed the cryo-engine with a phased development plant: one tonne, four tonne and final C-25.
Indian media and BBC used to report ominously about every minor misstep with motivated commentary and resulting heartburn on this forum.
* Defense News reporter Vivek Raghuvanshi used to come up with bogus horror stories about the potential usage of some of these cryo-engines with PSLV stages to lob a heavy hydrogen bomb in an ICBM. He definitely fed the fear in DC commentariat. One joker called Gary Milholin used to conjure up MTCR violation by FSU and Indian ICBM development. There was a huge NPA/MTCR chatteratti who got PhD theses on this convergence. Some are still spewing venom in influential US national security circles.
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Re: GSLV-Mk III launch program/post-launch analysis
Not all functions of a system can be implemented in a 'distributed' manner; so idea of a swarm of small satellites coming together to perform function of a much larger satellite may not satisfy all use cases . One key aspect which comes to my mind is OPTICs that is one area size cannot be compromised without a compromise in functionality or performance/resolution.
Re: GSLV-Mk III launch program/post-launch analysis
Bliss to check at 1:48-1:49 in this vid. Top right corner of the screen.
Bhaat eej that fast moving object ?
Not a kawwa, for sure.
Edit- made a gif of that object.
Last edited by nirav on 06 Jun 2017 23:04, edited 1 time in total.
Re: GSLV-Mk III launch program/post-launch analysis
If we look at Boeing 702SP series all electric satellites then even GSLV MK2 may be adequate by itself. The weight of 6 ton satellite may fall to 2500kg in all electric configuration.