Compersion
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oh man really was waiting for the launch. i guess it will be rescheduled. good for the checks.
ISRO General News and Updates
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trackwhack
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What is the procedure for defuelling?
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:dafuq: :dafuq:
Yep, the launch has been CALLED OFF.
So some more wait. But I prefer this to some momentary fireworks in the sky. The satellite itself is too expensive to be lost, not to talk of the cryogenic stage.
As of now, news is that the issue was with the second stage.... not the cryogenic one. But the second stage is the same as that of PSLV, isnt it? And PSLV has never failed since commercial flights began. That's a little intriguing.
venkat
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Sridhar .. I am surprised ro see such poor quality control from ISRO!!! dont they check for leaks before doing integration work? Ppropellant tanks in the vikas engine using ultrasonic leak checks... This is a workhorse for the PSLV work horse...cant believe it...that too this happened when ISRO is looking for successful launch...to err is human but....there are no action replays for the time lost...saving grace is that it got detected 74 minutes before launch...
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Successful Flight Test Validation Of The Very First Indian Strap-On Booster Motors
www.aame.in/2013/08/successful-flight-test-validation-of.html?m=1
www.aame.in/2013/08/successful-flight-test-validation-of.html?m=1
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'The Bicycle Era' Of India's Space Journey
www.aame.in/2013/08/bicycle-era-of-india-space-journey.html?m=1
www.aame.in/2013/08/bicycle-era-of-india-space-journey.html?m=1
Neil
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ISRO may use standby engine to launch GSLV
CHENNAI: Indian space agency ISRO will look at options of using a standby engine for the early launch of its heavy geosynchronous satellite launch vehicle (GSLV) after examining what forced the postponement of the launch Monday, an official said.
"We have a standby for the second stage engine. But first we have to study the problem. If the problem is due to a faulty component, then we have to look at the batch to which the component belonged and have to replace the entire components from that batch," an Indian Space Research Organisation (ISRO) official told IANS preferring anonymity.
He said there was no point in replacing an engine with another faulty one.
According to him, ISRO will look at different options like using a standby engine, replacing the component or correcting the problem.
"If the problem is external, it will be easy to correct. But if it is internal, then the engine may have to be dismantled," he said.
ISRO had called off the launch of its GSLV rocket carrying the communication satellite GSAT-14 after the liquid fuel started leaking like a tap from the rocket's second stage.
The GSLV is a three stage/engine with four strap-on motors hugging the first stage. The first stage is powered by solid fuel while the four strap-on motors and the second stage are powered by liquid fuel. The third is the cryogenic engine powered by liquid hydrogen and liquid oxygen.
"This is the first time we have seen such a fault," said a source close to ISRO.
According to officials, the second stage is identical for ISRO's two rockets - its lighter rocket polar satellite launch vehicle and GSLV.
While GSLV is under the development stage, the PSLV is termed as the space agency's workhorse and used to launch Indian and foreign satellites.
In 2010, ISRO had to postpone a PSLV launch as it found "a marginal drop in the pressure in the second stage of the vehicle during mandatory checks".
At that time the faulty part was inaccessible as the rocket stages had been fully assembled. ISRO had to dismantle the second stage to correct the fault.
In 2013, ISRO had to postpone the launch of its PSLV rocket carrying India's first navigational satellite after it found a problem in one of the electro-hydraulic control actuators in the second stage.
Here again, the fully assembled rocket had to be dismantled to replace the actuator, an assembly of several components.
In both cases, the second stage was not fuelled up and hence did not pose a problem for ISRO.
But the problem in the GSLV supposed to fly Aug 19 is complex as the leaking second stage was fuelled up and the third and critical stage - the cryogenic engine - was being fuelled for its flight.
"Some of the components in the second stage, like sealants, have limited life after fuelling. They might become brittle if not used within a specified period," officials told IANS.
The one comforting factor is that the crucial cryogenic engine is safe and it does not face such limited life component problems, an ISRO official IANS.
According to them, the first task for them is to drain the fuel from the second and third/cryogenic stage.
Following that, the engines will be decontaminated for fuel and traces of fuel.
"Then the rocket will be moved back to the assembly building and a detailed study of the problem will be made and corrective action will be taken," the official said.
However, ISRO officials could not say when the rocket would be ready for launch.
"Advanced countries test their stages several times before it is used in a rocket. In India, owing to vendor constraints, we have to make our rockets operational after a few tests," R.V. Perumal a retired ISRO rocket expert said.
ISRO may use standby engine to launch GSLV - The Economic Times
CHENNAI: Indian space agency ISRO will look at options of using a standby engine for the early launch of its heavy geosynchronous satellite launch vehicle (GSLV) after examining what forced the postponement of the launch Monday, an official said.
"We have a standby for the second stage engine. But first we have to study the problem. If the problem is due to a faulty component, then we have to look at the batch to which the component belonged and have to replace the entire components from that batch," an Indian Space Research Organisation (ISRO) official told IANS preferring anonymity.
He said there was no point in replacing an engine with another faulty one.
According to him, ISRO will look at different options like using a standby engine, replacing the component or correcting the problem.
"If the problem is external, it will be easy to correct. But if it is internal, then the engine may have to be dismantled," he said.
ISRO had called off the launch of its GSLV rocket carrying the communication satellite GSAT-14 after the liquid fuel started leaking like a tap from the rocket's second stage.
The GSLV is a three stage/engine with four strap-on motors hugging the first stage. The first stage is powered by solid fuel while the four strap-on motors and the second stage are powered by liquid fuel. The third is the cryogenic engine powered by liquid hydrogen and liquid oxygen.
"This is the first time we have seen such a fault," said a source close to ISRO.
According to officials, the second stage is identical for ISRO's two rockets - its lighter rocket polar satellite launch vehicle and GSLV.
While GSLV is under the development stage, the PSLV is termed as the space agency's workhorse and used to launch Indian and foreign satellites.
In 2010, ISRO had to postpone a PSLV launch as it found "a marginal drop in the pressure in the second stage of the vehicle during mandatory checks".
At that time the faulty part was inaccessible as the rocket stages had been fully assembled. ISRO had to dismantle the second stage to correct the fault.
In 2013, ISRO had to postpone the launch of its PSLV rocket carrying India's first navigational satellite after it found a problem in one of the electro-hydraulic control actuators in the second stage.
Here again, the fully assembled rocket had to be dismantled to replace the actuator, an assembly of several components.
In both cases, the second stage was not fuelled up and hence did not pose a problem for ISRO.
But the problem in the GSLV supposed to fly Aug 19 is complex as the leaking second stage was fuelled up and the third and critical stage - the cryogenic engine - was being fuelled for its flight.
"Some of the components in the second stage, like sealants, have limited life after fuelling. They might become brittle if not used within a specified period," officials told IANS.
The one comforting factor is that the crucial cryogenic engine is safe and it does not face such limited life component problems, an ISRO official IANS.
According to them, the first task for them is to drain the fuel from the second and third/cryogenic stage.
Following that, the engines will be decontaminated for fuel and traces of fuel.
"Then the rocket will be moved back to the assembly building and a detailed study of the problem will be made and corrective action will be taken," the official said.
However, ISRO officials could not say when the rocket would be ready for launch.
"Advanced countries test their stages several times before it is used in a rocket. In India, owing to vendor constraints, we have to make our rockets operational after a few tests," R.V. Perumal a retired ISRO rocket expert said.
ISRO may use standby engine to launch GSLV - The Economic Times
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not being sarcastic'The Bicycle Era' Of India's Space Journey
www.aame.in/2013/08/bicycle-era-of-india-space-journey.html?m=1
i really love this whatever it takes attitude to move forward
i wish we could apply the same to all other areas of indian life
Decklander
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Waiting for your reply
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Any idea when its been rescheduled to ?
it will be atleast a month, if not two. but it won't be 1 year or 6 months time period.
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It depends , If the leak was a small manufacturing defect 1 or 2 months as sukhish said . But will take more otherwise. Also we have Other important launches in coming months. Particularly the Mars Orbiter , the launch window we cannot miss ...
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GSLV-D5 safe after fuel is drained, to be moved out of launch pad on August 25
Arun Ram, TNN Aug 20, 2013, 04.43PM IST
CHENNAI: It was a tense night at the Sriharikota spaceport after a leak was detected in the liquid propellant tank of GSLV-D5 two hours before its scheduled launch at 4.50pm.
Isro scientists have remotely drained the fuels from the second stage and the indigenous cryogenic engine. Isro chairman K Radhakrishnan told TOI that the draining process was completed on Tuesday morning. "It's still not safe to go near the rocket because there could be fumes and other impurities in the air. We will move the vehicle to the assembly building on Sunday or Monday to ascertain the damage," he said.
The GSLV-D5 launch has been a much awaited milestone for the Indian Space Research Organisation as it uses an indigenous cryogenic engine. After the US imposed sanctions post Pokhran II in 1998, Russia, which was the sole supplier of cryogenic engine, refused to part with the technology, forcing India to accelerate its cryogenic engine project which started in the early 1990s. With six of the seven Russian cryogenic engines in Isro's custody being used up, India has no option but to develop its own to launch satellites weighing up to 5,000kg.
It is also vital for India's proposed manned mission to space.
Cryogenics, the science of extreme low temperatures, has remained a tricky technology to tame, with only the US, Russia, China, Japan and the European Space Agency mastering it. Isro's Liquid Propulsion Systems Centre in Mahendragiri in Tamil Nadu developed the indigenous engine which was to propel GSLV-D5 carrying telecommunication satellite GSAT-14 on Monday.
About two hours before the launch a camera caught the leak that appeared like a smoke coming out of the second stage of the rocket. "We don't know yet if the tank or any of the components was damaged. We will know by Monday," Radhakrishnan said. Asked if the rocket would have been destroyed in flight had the leak been not detected, the Isro chairman said the system would have anyway found it out before the launch. "We can't say if we would've lost the vehicle (if the leak was not detected)," he said.
GSLV-D5 safe after fuel is drained, to be moved out of launch pad on August 25 - Times Of India
Arun Ram, TNN Aug 20, 2013, 04.43PM IST
CHENNAI: It was a tense night at the Sriharikota spaceport after a leak was detected in the liquid propellant tank of GSLV-D5 two hours before its scheduled launch at 4.50pm.
Isro scientists have remotely drained the fuels from the second stage and the indigenous cryogenic engine. Isro chairman K Radhakrishnan told TOI that the draining process was completed on Tuesday morning. "It's still not safe to go near the rocket because there could be fumes and other impurities in the air. We will move the vehicle to the assembly building on Sunday or Monday to ascertain the damage," he said.
The GSLV-D5 launch has been a much awaited milestone for the Indian Space Research Organisation as it uses an indigenous cryogenic engine. After the US imposed sanctions post Pokhran II in 1998, Russia, which was the sole supplier of cryogenic engine, refused to part with the technology, forcing India to accelerate its cryogenic engine project which started in the early 1990s. With six of the seven Russian cryogenic engines in Isro's custody being used up, India has no option but to develop its own to launch satellites weighing up to 5,000kg.
It is also vital for India's proposed manned mission to space.
Cryogenics, the science of extreme low temperatures, has remained a tricky technology to tame, with only the US, Russia, China, Japan and the European Space Agency mastering it. Isro's Liquid Propulsion Systems Centre in Mahendragiri in Tamil Nadu developed the indigenous engine which was to propel GSLV-D5 carrying telecommunication satellite GSAT-14 on Monday.
About two hours before the launch a camera caught the leak that appeared like a smoke coming out of the second stage of the rocket. "We don't know yet if the tank or any of the components was damaged. We will know by Monday," Radhakrishnan said. Asked if the rocket would have been destroyed in flight had the leak been not detected, the Isro chairman said the system would have anyway found it out before the launch. "We can't say if we would've lost the vehicle (if the leak was not detected)," he said.
GSLV-D5 safe after fuel is drained, to be moved out of launch pad on August 25 - Times Of India
