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GSLV-D3 / GSAT-4 launch - April 15, 2010
by
input~2
on 20 Sep, 2009 06:06
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First GSLV-MKII confirmed for this launch.
source
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#1
by
hornbill2007
on 20 Sep, 2009 13:59
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That will be one of the most crucial flights for India's space programme. I would rank it with Chandrayan 1 flight because a country's space future depends on indigenous ability to lift heavy satellites to higher orbits.
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#2
by
tappa
on 21 Sep, 2009 08:49
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#3
by
hornbill2007
on 10 Nov, 2009 10:47
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Has the cryogenic stage been integrated into the launch vehicle?
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#4
by
johnxx9
on 10 Nov, 2009 16:42
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Has the cryogenic stage been integrated into the launch vehicle?
Most probably yes
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#5
by
m.prasad
on 11 Dec, 2009 04:54
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#6
by
James1
on 26 Feb, 2010 03:52
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I've deliberately not included data on performance, reliability, or anything else because that would distract us from the most striking observation about these vehicles; each and every one of them, whatever the technology, country of origin, original design intent, launch history, fuel and oxidiser, success or failure in the commercial launch market, have mission costs in ranging from tens to hundreds of millions of US$.
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#7
by
tonthomas
on 09 Mar, 2010 06:38
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#8
by
seshagirib
on 10 Apr, 2010 04:11
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#9
by
Shturmanskie
on 10 Apr, 2010 13:27
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Way to go India!!
I am sure many key players worldwide will be nervously monitoring this launch.
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#10
by
Satori
on 11 Apr, 2010 13:06
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#11
by
seshagirib
on 13 Apr, 2010 05:23
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#12
by
Zipi
on 13 Apr, 2010 08:24
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#13
by
Zipi
on 13 Apr, 2010 11:00
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And 3 videos in indian language, but includes some nice footage from the launch vehicle.
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#14
by
seshagirib
on 13 Apr, 2010 17:27
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#15
by
tonthomas
on 15 Apr, 2010 09:22
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GSLV-D3 on Pad (Vids with english comments):
Thomas
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#16
by
Satori
on 15 Apr, 2010 10:35
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GSLV-D3 minutes wawy from launch...
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#17
by
Satori
on 15 Apr, 2010 10:54
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Everything os go! Authorization for launch has been given!
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#18
by
Spiff
on 15 Apr, 2010 10:54
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3 minutes and counting.
(can't do screenshots. Sorry...)
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#19
by
Satori
on 15 Apr, 2010 10:54
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#20
by
Satori
on 15 Apr, 2010 10:56
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#21
by
Spiff
on 15 Apr, 2010 10:57
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Launch!
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#22
by
Satori
on 15 Apr, 2010 10:58
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#23
by
Satori
on 15 Apr, 2010 10:59
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#24
by
Spiff
on 15 Apr, 2010 11:00
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1st stage sep.
2nd stage ignition
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#25
by
Satori
on 15 Apr, 2010 11:00
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1 - 2 sep
Second Stage ignition!!!
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#26
by
Spiff
on 15 Apr, 2010 11:01
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3.5 km/s
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#27
by
Satori
on 15 Apr, 2010 11:02
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Ignition of India's crio stage after second stage sep!!!
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#28
by
Spiff
on 15 Apr, 2010 11:03
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India's indigenous cryogenic engine firing
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#29
by
Spiff
on 15 Apr, 2010 11:03
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uh oh.....
telemetry on screen does not look good....
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#30
by
stockman
on 15 Apr, 2010 11:05
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uh oh.....
telemetry on screen does not look good....
\
yea thats going the wrong direction.....
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#31
by
Spiff
on 15 Apr, 2010 11:05
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'deviation of performance'
graphs look rather ballistic (my opinion)
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#32
by
William Graham
on 15 Apr, 2010 11:07
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Rocket is reported to be underperforming.
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#33
by
Spiff
on 15 Apr, 2010 11:08
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telemetry lost...
ticker on screen is still screaming 'historic launch' and such, but I fear this is a failure.
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#34
by
Satori
on 15 Apr, 2010 11:08
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Humm, so me kind pf problem with the crio stage...
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#35
by
sanman
on 15 Apr, 2010 11:09
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I think they've lost the rocket
Right after the indigenous cryo engine ignited, the thing started deviating from the predicted plot
No telemetry being received back - it's a goner
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#36
by
William Graham
on 15 Apr, 2010 11:10
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Reporters state that there has been a "major performance loss"
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#37
by
Satori
on 15 Apr, 2010 11:11
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Looks like data was lost from T+505s...
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#38
by
Skyrocket
on 15 Apr, 2010 11:12
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Guess some scientists are glad now, that their TAUVEX II payload was bumped from this mission.
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#39
by
Satori
on 15 Apr, 2010 11:14
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Well, sadly we have the first launch failure of the year
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#40
by
William Graham
on 15 Apr, 2010 11:15
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Failure confirmed
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#41
by
Satori
on 15 Apr, 2010 11:16
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Official: launch failure. Rocket did'nt got into orbit...
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#42
by
Spiff
on 15 Apr, 2010 11:18
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statement by ISRO
Cryo engine confirmed as ignited
Stage was tumbling and out of control
Detailed analysis to follow
(Indian english is hard to follow...)
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#43
by
Satori
on 15 Apr, 2010 11:18
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Looks like the problem was related with the no ignition of the verniers on the India's Crio Stage?
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#44
by
Spiff
on 15 Apr, 2010 11:19
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And then some statements about thorough investigation and making sure next launches won't fail as well. The usual stuff really....
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#45
by
sanman
on 15 Apr, 2010 11:31
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They suspect that the 2 verniers which provide stability control didn't function properly, and this caused the upper stage to tumble out of control.
It's a little early to know, though.
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#46
by
Satori
on 15 Apr, 2010 11:39
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Next launch of GSLV with a Indian third stage will take place in one year.
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#47
by
Zipi
on 15 Apr, 2010 11:50
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#48
by
Zipi
on 15 Apr, 2010 13:20
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Better launch video:
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#49
by
WHAP
on 15 Apr, 2010 14:55
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In the second video Zipi posted, did the director say "non ignition of the cryo" or was it just clipped? Do other upper stages use verniers for control? SpaceX, Atlas, Delta all seem to do fine with a single main engine.
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#50
by
spacex
on 15 Apr, 2010 15:13
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Developing a cryo engine is not an easy task. Hopefully they will identify the problems and the next launch will be successful.
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#51
by
just-nick
on 15 Apr, 2010 15:44
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Frustrating day for everyone in the Indian space program. I really admired their pluck to methodically develop these indigenous solutions.
Good luck...
Anyway, got a question. From what I know, the GSLV "stage 0" boosters burn longer than the "stage 1" core. How's that handled? Is it not a parallel-burn (like the Titan III/IV, not the Delta/Atlas)?
--Nick
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#52
by
ugordan
on 15 Apr, 2010 15:57
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From what I know, the GSLV "stage 0" boosters burn longer than the "stage 1" core. How's that handled? Is it not a parallel-burn (like the Titan III/IV, not the Delta/Atlas)?
Why would that pose a problem if the liquids have control authority?
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#53
by
Dmitry_V_home
on 15 Apr, 2010 17:39
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All it is very sad. But, I hope, Indians can quickly define and eliminate causes of accident.
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#54
by
just-nick
on 15 Apr, 2010 18:01
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From what I know, the GSLV "stage 0" boosters burn longer than the "stage 1" core. How's that handled? Is it not a parallel-burn (like the Titan III/IV, not the Delta/Atlas)?
Why would that pose a problem if the liquids have control authority?
It just is an unusual way of doing things, I guess.
You'd be pushing the big burned out husk of the solid stage 1 for a good extra minute and paying the mass/drag penalties for that.
--Nick
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#55
by
tonthomas
on 15 Apr, 2010 19:32
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#56
by
sanman
on 16 Apr, 2010 00:55
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
Anyway, just my personal opinion.
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#57
by
Art LeBrun
on 16 Apr, 2010 02:14
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
Anyway, just my personal opinion.
Makes sense. Why would a failure of two verniers cause anything but a roll issue? I assume the engine gimbals in pitch and yaw. Anyway a shocking development for modern spaceflight.
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#58
by
edkyle99
on 16 Apr, 2010 04:31
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
Anyway, just my personal opinion.
Makes sense. Why would a failure of two verniers cause anything but a roll issue? I assume the engine gimbals in pitch and yaw. Anyway a shocking development for modern spaceflight.
I agree about the vernier control, etc. Seems likely a main propulsion failure at, or shortly after, the planned ignition time.
A rough start for India, but ISRO might find solace in the fact that five of the first seven Atlas/Centaur flights failed, that Europe's Ariane cryo stage suffered its fair share of failures (five I think) during the early days, that RL10 and Centaur and Long March and H-II(A) have continued to give occasional heartache even in recent years, and so on.
This stuff isn't easy.
- Ed Kyle
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#59
by
avollhar
on 16 Apr, 2010 05:01
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Verniers: could it be that the verniers also provide settling of cryo liquids for stage ignition? I think they were called ullage motors on the Saturn V.. if these fail to ignite, the turbopumps potentially run dry -> no stage ignition.
Just a wild thought..
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#60
by
jcm
on 16 Apr, 2010 07:01
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A rough estimate suggests that GSLV-D3 reached a -4400 x 137 km x 19.4 deg orbit
and reentered over the Andaman Sea at around 95E 9N +/- a few deg.
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#61
by
osiossim
on 16 Apr, 2010 07:27
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#62
by
input~2
on 16 Apr, 2010 09:18
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
I tend to agree, as supported by these telemetry data (extracted from various live broadcasts):
Time (s) velocity (km/s) altitude (km) event
262.8 4.113 127.5
263.8 4.138 127.8
290.4 GS2 Shutoff
293.0 GS2 Separation
297.0 4.898 134.7
298.0 4.898 134.9
299.0 4.898 135.1
300.0 4.898 135.3
301.0 4.897 135.5
304.9 CUS Ignition
308.0 4.895 136.5
309.0 4.895 136.7
310.0 4.895 136.8
316.0 4.893 137.5
317.0 4.893 137.6
318.0 4.893 137.7
319.0 4.893 137.8
320.0 4.893 137.8
321.0 4.893 137.9
322.0 4.893 138.0
323.0 4.893 138.0
324.0 4.892 138.1
325.0 4.892 138.2
326.0 4.892 138.2
327.0 4.892 138.3
328.0 4.892 138.3
329.0 4.892 138.3
373.0 4.899 134.9
379.0 4.901 133.7
446.5 4.951 107.4
505.0 5.023 65.9
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#63
by
kanaka
on 16 Apr, 2010 10:43
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We should have real time simulated flight - testing system instead of direct test flight. Atlest we should have some dummy payloads or components. This would help in minimizing cost as well as risks.
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#64
by
just-nick
on 16 Apr, 2010 14:33
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
Anyway, just my personal opinion.
Makes sense. Why would a failure of two verniers cause anything but a roll issue? I assume the engine gimbals in pitch and yaw. Anyway a shocking development for modern spaceflight.
I wouldn't assume that the verniers were for roll only. Zenit and Soyuz both, I believe, use fixed engines with verniers (Zenit 2nd stage) for pitch, roll, and yaw.
--N
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#65
by
jcm
on 16 Apr, 2010 18:38
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
Anyway, just my personal opinion.
Makes sense. Why would a failure of two verniers cause anything but a roll issue? I assume the engine gimbals in pitch and yaw. Anyway a shocking development for modern spaceflight.
I wouldn't assume that the verniers were for roll only. Zenit and Soyuz both, I believe, use fixed engines with verniers (Zenit 2nd stage) for pitch, roll, and yaw.
--N
If it tumbled right away, the cryo engine could have ignited but not yielded a net velocity change. However I tend to suspect that there was no ignitiion. Condolences to my friends on the ISRO team - I have confidence that they will fix this and make this engine work in the future.
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#66
by
Art LeBrun
on 16 Apr, 2010 18:46
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In watching the velocity numbers from the video, I didn't see the expected velocity increase that should have occurred following cryo engine ignition. So in my own humble opinion, I don't think that the cryo engine ignited.
Anyway, just my personal opinion.
Makes sense. Why would a failure of two verniers cause anything but a roll issue? I assume the engine gimbals in pitch and yaw. Anyway a shocking development for modern spaceflight.
I wouldn't assume that the verniers were for roll only. Zenit and Soyuz both, I believe, use fixed engines with verniers (Zenit 2nd stage) for pitch, roll, and yaw.
--N
Good point - I must have thought more than 2 would be required for pitch and yaw. Perhaps one vernier ignited to cause the tumbling....
if tumbling is the correct term?
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#67
by
sanman
on 17 Apr, 2010 00:38
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#68
by
input~2
on 17 Apr, 2010 15:45
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From the Hindu front page (17April 2010)
Why didn't the cryogenic engine ignite? The cryogenic engine has not ignited, that is for sure.
It is very clear that the cryogenic engine did not ignite when you look at the curve [of the vehicle's trajectory], everything was normal up to the GS2 [second stage] shutdown. Then you can see clearly that there is no increment in the vehicle's velocity. The velocity is the same. It started losing its altitude also.
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#69
by
Art LeBrun
on 17 Apr, 2010 15:54
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Interesting - where is the data for engine chamber pressure, pump speeds, propellant flow and pressures and other information? New vehicle would have lots of detailed telemetry? Maybe the information will come out later.
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#70
by
sanman
on 17 Apr, 2010 17:07
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I wonder if India's going to have to build a dedicated vacuum test facility now, or if they can rent someone else's.
As I mused in another thread, I wonder if it's possible to just float an engine test rig up on a balloon to some high altitude, in order to test-fire it. Otherwise, there would seem to be a huge amount of engineering involved in building a ground-based vacuum test facility.
Or else perhaps India could have used its older, cheaper ASLV rocket to loft the new engine upto 50 miles altitude for suborbital flight-testing.
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#71
by
Damon Hill
on 17 Apr, 2010 22:31
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I wonder if India's going to have to build a dedicated vacuum test facility now, or if they can rent someone else's.
As I mused in another thread, I wonder if it's possible to just float an engine test rig up on a balloon to some high altitude, in order to test-fire it. Otherwise, there would seem to be a huge amount of engineering involved in building a ground-based vacuum test facility.
How big will the balloon need to be to support the weight of the engine, propellant supply and instrumentation, and support structure?
How will this flying arrangement compensate for thousands of pounds of thrust, in whatever direction?
I suspect the real problem with the Indian engine will be something other than the vacuum condition. If ISRO doesn't have a altitude compensating test chamber, it's time they build one. Do you know how it works? It's surprisingly simple in principle.
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#72
by
sanman
on 17 Apr, 2010 23:16
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How big will the balloon need to be to support the weight of the engine, propellant supply and instrumentation, and support structure?
How will this flying arrangement compensate for thousands of pounds of thrust, in whatever direction?
Hmm, I suppose that it would be a very giant balloon, but that this would be much cheaper than an actual rocket test flight. Plus, the balloon could be tethered to compensate for the engine thrust. Yes, this would be a very long tether.
I suspect the real problem with the Indian engine will be something other than the vacuum condition. If ISRO doesn't have a altitude compensating test chamber, it's time they build one. Do you know how it works? It's surprisingly simple in principle.
India does not have a macro-scale vacuum test chamber, and vacuum conditions were not simulated in ground testing of the engine. I think they may have tried to simulate this merely through numerical methods, and not through an actual test-firing under these conditions.
From what I've read, these vacuum chambers work through "steam ejectors" which not only have to produce a vacuum, but have to maintain it in the face of the huge exhaust put out by the engine being tested.
Perhaps it would be easier just to rent somebody else's in the near term, and consider building one for the long haul.
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#73
by
Damon Hill
on 18 Apr, 2010 02:10
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I suspect the real problem with the Indian engine will be something other than the vacuum condition. If ISRO doesn't have a altitude compensating test chamber, it's time they build one. Do you know how it works? It's surprisingly simple in principle.
India does not have a macro-scale vacuum test chamber, and vacuum conditions were not simulated in ground testing of the engine. I think they may have tried to simulate this merely through numerical methods, and not through an actual test-firing under these conditions.
From what I've read, these vacuum chambers work through "steam ejectors" which not only have to produce a vacuum, but have to maintain it in the face of the huge exhaust put out by the engine being tested.
Perhaps it would be easier just to rent somebody else's in the near term, and consider building one for the long haul.
The steam ejector works initially to pump down the chamber; the high speed exhaust of the engine being tested does the rest of the work.
Russia has a couple of dandy facilities, and India has traditionally worked closely with them.
But let's wait for a failure analysis to point to the real problem. Quite a number of things could have caused this. Liquid hydrogen has an annoying tendency to freeze anything that's not helium, for example.
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#74
by
WHAP
on 18 Apr, 2010 02:30
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Interesting - where is the data for engine chamber pressure, pump speeds, propellant flow and pressures and other information? New vehicle would have lots of detailed telemetry? Maybe the information will come out later.
It's likely with ISRO, and won't be released unless and until they feel it's necessary. I suspect that would be never.
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#75
by
tonthomas
on 18 Apr, 2010 15:38
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#76
by
tonthomas
on 18 Apr, 2010 15:50
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So may be the verniers have had to work as ullage motors for fuel settling but failed. The main motor made a short burp and starved without fuel.
Thomas
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#77
by
Art LeBrun
on 18 Apr, 2010 15:57
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Since this was still a high velocity flight why do you need to settle fully loaded cryogenic propellants with ullage pressures in place?
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#78
by
tonthomas
on 18 Apr, 2010 16:14
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Don´t think velocity is the factor. But interesting to know should be if there was driven flight of the third stage, and, concerning stage pressurisation, in which way it was realised. Besides the pressure, the aggregate phase matters, and i think, the motors turbomachinery is not designed to pump gaseous O2 oder H2.
Thomas
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#79
by
sanman
on 18 Apr, 2010 19:04
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#80
by
ugordan
on 18 Apr, 2010 19:12
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Interesting. The pump did start but failed immediately. Wouldn't that suggest the failure mode could be reproduced without a vacuum chamber?
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#81
by
Art LeBrun
on 18 Apr, 2010 19:15
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Possible broken output shaft or gearbox failure............other scenarios?
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#82
by
avollhar
on 18 Apr, 2010 19:32
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Since this was still a high velocity flight why do you need to settle fully loaded cryogenic propellants with ullage pressures in place?
What has velocity to do with it? It's about acceleration and the lack of it (or gravity) means that there is a possibility of gaseous H2/O2 at the turbopump inlet rather than LH2/LOX.. which could result in the 'burp'.
Even when fully loaded you have some gas reservoir to pressurize the tanks.
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#83
by
Art LeBrun
on 18 Apr, 2010 19:49
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My point is that tanks are pressurized when fully loaded which helps to seat the propellants gravity or not. I will concede that gaseous condition could occur in a feedline. After a first burn then a gaseous condition will occur.
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#84
by
ugordan
on 18 Apr, 2010 19:53
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My point is that tanks are pressurized when fully loaded which helps to seat the propellants gravity or not.
Pressurization itself does not help seat the propellants. There is still nothing forcing the ullage to remain at the top of the tank in zero G. Most vehicles today however can live with that because the ignition of the stage comes soon after cutoff of previous stage so the gas bubble does not have time to travel to the feedline inlet at the tank bottom.
As to the failure in question, I wonder if cavitation could be an issue? On the ground they have the increased pump inlet pressure due to weight of the propellant, that would be missing in flight. Seems like a silly mistake to make, though.
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#85
by
input~2
on 18 Apr, 2010 20:11
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Screenshot from televised video at T
0+505s when telemetry link was lost (curves and scales have been colored for better readability)
- Nominal altitude vs time in green
- Nominal relative velocity vs time in magenta
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Observed deviations in redGS2 IGN = second stage ignition
CUS IGN = third stage ignition
CUS OFF = third stage cut-off
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#86
by
tonthomas
on 18 Apr, 2010 20:17
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So what happened between 290.4 s (shutdown of second stage) and 304.9 s (third stage main engine(?) ignition)?
The turbine that spins the fuel pump may have failed (said in already mentioned
http://beta.thehindu.com/sci-tech/technology/article402907.ece) - because of overspeed from a dry pump, other (mechanical) causes, or i.e. there was no gas to drive the turbine longer...
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#87
by
seshagirib
on 19 Apr, 2010 05:26
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My understanding of the cryogenic engine is H and O2 pumps are driven by the turbine, but how are the pumps driven before ignition? battery driven?
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#88
by
s^3
on 19 Apr, 2010 11:16
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Screenshot from televised video at T0+505s when telemetry link was lost (curves and scales have been colored for better readability)
- Nominal altitude vs time in green
- Nominal relative velocity vs time in magenta
- Observed deviations in red
GS2 IGN = second stage ignition
CUS IGN = third stage ignition
CUS OFF = third stage cut-off
Using the data given in earlier post
[290.4 GS2
293 GS2
297 4.898
298 4.898
299 4.898
300 4.898
301 4.897
304.9 CUS
308 4.895
309 4.895
310 4.895
316 4.893
317 4.893
318 4.893
319 4.893
320 4.893
321 4.893
322 4.893
323 4.893
324 4.892
325 4.892
326 4.892
327 4.892
328 4.892
329 4.892
373 4.899
379 4.901
446.5 4.951
505 5.023]
I plotted the graph and added trendlines.
Velocity is continuously falling from 293 ( GS2 Shutoff/seperation ) to 329 seconds indicating that there is no force operating to increase the velocity ( Velocity falls from 4.898 to 4.892 ) .
After that the kinetic energy attained by previous ignitions is finished and the free fall starts increasing the freefall velocity to 4.892 to 4.899... from 329 to 373... onwards upto 5.203 at 505 seconds.
So.. even if the cryo ignited it did not impart any force towards increasing the velocity of the rocket.
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#89
by
input~2
on 19 Apr, 2010 14:37
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So.. even if the cryo ignited it did not impart any force towards increasing the velocity of the rocket.
I tend to agree. This is illustrated below when zooming in from my
earlier graph on the period around CUS IGN.
Edit: I have added trendlines
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#90
by
sanman
on 19 Apr, 2010 17:24
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Well, against the claim of ~1 sec burn of cryo engine, it's rather hard to tell. You'd have to superimpose a linear plot against a ballistic curve, and for such a short interval relative to the data points available, it's hard to interpolate whether or not some slight acceleration was imparted.
If ISRO can release more detailed flight telemetry data, then more accurate analysis would be possible. Otherwise, it's hard to discern the difference between ~1sec burn and non-ignition based on the data points we now have available.
I do wish that ISRO would also have cameras aboard their launch vehicles, as these can provide important information on the flight, as well as serving as a valuable historical record of a milestone achievement in the country's space progress.
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#91
by
input~2
on 28 Apr, 2010 09:46
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Indian launches are never insured
(
source)
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#92
by
input~2
on 05 May, 2010 20:19
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An interesting article on the failure just published by the Indian Front Line magazine "
Cryogenic setback"
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#93
by
kanaka
on 06 May, 2010 05:37
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Good Article. Can't we have real time simulators for simulating the flight test before going for actual test? This would save loss of vehicle or satellite. ISRO should have gone with a dummy satellite (rocks even !!!
of equal weight instead of trying with original satellite while doing experiemnts. This saves cost in case of failuare.
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#94
by
ugordan
on 06 May, 2010 09:07
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ISRO should have gone with a dummy satellite (rocks even !!! of equal weight instead of trying with original satellite while doing experiemnts. This saves cost in case of failuare.
And if you're launching with the logic assumption the flight will go well (otherwise why do you feel you're ready for the launch?) and it
does go well, you just wasted one working vehicle on rocks. Meanwhile, there are countless payloads sitting on the ground that would take any chance they can get just to get a ride to space, no matter how risky.
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#95
by
kanaka
on 06 May, 2010 09:20
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satellite is more expensive than working vehicle. simulators with real time parameters are better for simulated flight testing before going for actual test
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#96
by
ugordan
on 06 May, 2010 10:49
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Why then do you think anyone puts a paying customer on any inaugural flight?
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#97
by
input~2
on 06 May, 2010 12:59
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GSLV failure analysis report expected in mid June (
source)
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#98
by
seshagirib
on 29 Jun, 2010 16:55
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of equal weight instead of trying with original satellite while doing experiemnts. This saves cost in case of failuare.