Cataloguing reasons for AGNI & GSLV launch failures

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Post by neel »

I think that the real problem is the lack of discretion and funding for project leaders to do robust testing. If there was the money and opportunity to test even ~10x as much as what happens at present, the A3 would have had this failure a year ago and it would have been rectified by now as it would have been known previously. When pursuing new R&D efforts it is imperative that there be full capability to test at each step along the way, rather than the current system of waiting for parliamentary approval and piling tests of all components into one approved test run.
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Post by Ananth »

http://www.hindu.com/2006/07/12/stories ... 101000.htm
The GSLV's lift-off had gone smoothly and the rocket majestically cleared the launch tower. The problem that doomed the rocket appeared soon afterwards. Going by what ISRO chairman G. Madhavan Nair subsequently told reporters, one of the rocket's four strap-ons malfunctioned and the rocket went uncontrollably off-course.

[..]

The malfunction on the latest GSLV flight, where one of the Vikas engines suddenly stopped producing any thrust, bears resemblance to the problem that occurred during the first attempt to launch the GSLV in March 2001. On that occasion, the automatic launch system found that one of the strap-ons was not producing adequate thrust and aborted the launch just one second before lift-off. The problem was traced to defective plumbing that reduced the flow of one of the liquid propellants to the Vikas engine. Could it be that a manufacturing defect of some sort or perhaps an unexpected component failure affected Monday's flight of the GSLV? This is the sort of question that the proposed high-level inquiry committee will no doubt address.
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Post by Ananth »

http://www.domain-b.com/organisation/is ... stroy.html
Located away from the mission control room, the group monitors the flight path diligently plotting the Instantaneous Impact Point (IIP)-the point where the vehicle or its debris would fall. According to an official of Indian Space Research Organisation (ISRO), the group is totally independent and does not need to get prior sanction to destruct the vehicle if required.

On July 10, 2006, when the group saw the GSLV F02 going awry, the leader of the group pressed the "destroy" button. Forty-five seconds after GSLV F02 lifted-off, it was destroyed when it went out of control. "The vehicle at that time was 15km over the sea and the debris would not have fallen on land even if the vehicle was not destroyed," said an official.

[..]
As per the original flight plan, the GS1 — the first stage — should burn out in 149.7 seconds at an altitude of 70.4km when the vehicle is moving at a velocity of 2.8km per second. The heat-shield separation is at 228.9 seconds (altitude 115 km, vehicle speed 3.9km per second), the GS2 burnout at 290.6 seconds (131.9km, speed 5.4km per second), GS3 burnout at 1,002.5km (220.2km, speed 10.2km per second) and the satellite separates 13 seconds after that.

But within 45 seconds of the take off the vehicle went off its path and send this article to a friendalso did not develop the required speed. So at the time of destruction, the second- and third-stage fuel and also the fuel in the satellite must have exploded resulting in a huge flame ball. Had it not been for the overcast sky, the spectacle would have been visible from the earth.
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Post by Ananth »

http://www.domain-b.com/organisation/is ... _gslv.html
Sitting in the mission control room, Nair made the initial announcement, "There seems to be a mishap in the first stage. Things have gone wrong. We have to analyse the data and see the sequence."

According to him, the lift-off was normal and for the initial 40-45 seconds the vehicle was under control. But the thrust pressure in one of the four strap-on motors fell to zero soon after the lift-off, causing the vehicle to lose its balance and veer out of control.

[..]

While not ruling out sabotage in the GSLV's failure, Nair said, "We have to analyse the data up till the last 60 seconds. The lift-off video will be analysed in detail. I am sure we will pin-point the fault." The data analysis has started at the mission control facility.

It should also be noted that the first flight of GSLV was aborted on March 28, 2001, as one of the strap-on motors did not develop the required thrust. It was then established that the fault was in the defective plumbing in the oxidiser flow-line.
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Post by SaiK »

normally, what would be the design of strap-ons, would they be derated or doubled up, just in case one fails, automatically shut/released and symmetrically opposite strap on could have shut down/released to equalize.. of course this can happen only if only 4 straps are required, and we go ahead add extra 4 more adjacent as standby.

!?
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Post by Ananth »

courtesy Gerard from GSLV thread.

http://www.hindu.com/2006/07/12/stories ... 981500.htm
The reason behind the pressure in one of the strap-on booster motors of the GSLV flight on July 10 dropping to zero and the motor not developing enough thrust "is the point we have to go into in detail" during the failure analysis of the flight, said G. Madhavan Nair, chairman, Indian Space Research Organisation (ISRO).

He said he had appointed a high-power committee headed by K. Narayana to go into the failure of the GSLV-F02 (Geo-synchronous Satellite Launch Vehicle) that lifted off from Sriharikota on July 10 but plunged into the Bay of Bengal.

The committee would go into volumes of data, analyse it and submit a report within a month. The committee will comprise top ISRO engineers and members of national laboratories and academic institutions. Mr. Narayana retired as Director, Satish Dhawan Space Centre, Sriharikota, Andhra Pradesh.

[..]

Answering a question on thrust not developing in one of the strap-on motors of the first GSLV flight in 2001, the computer aborting the flight then and saving the vehicle, and why the computer did not halt the flight now, Mr. Madhavan Nair asserted that "it is not a similar phenomenon." In the GSLV's first flight, "the thrust did not build up to an adequate level (before the lift-off). Our computers detected it and stopped the flight. Here the thrust build-up was as expected. So we took a decision to go.

After the vehicle lifted off, the pressure in one of the strap-on engines dropped to zero. That is the point we have to go into in detail," the ISRO Chairman said. After the pressure in one of the strap-on engines dropped to zero, "it became impossible to save the vehicle."

[..]

Top ISRO brass including Mr. Madhavan Nair; B.N. Suresh, Director, Vikram Sarabhai Space Centre, Thiruvananthapuram; M. Annamalai, Director, SDSC, tried to pinpoint on Tuesday how the whole sequence of events took place. "We did simulation," the ISRO Chairman said. The simulation showed how the pressure in one of the strap-on engines dropped to zero, how the thrust did not build up, the vehicle's consequent trajectory, the play of wind, how "the vehicle turned to one side" with the build-up of all these factors and crashed into the sea.

The GSLV-F02 was designed to withstand four degrees of angle of attack in its flight trajectory. With 10 degree of angle of attack, the vehicle broke up. "It withstood double the value of angle of error," Mr. Madhavan Nair said. But there was no control of the vehicle and it went down.
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Post by Ananth »

SaiK wrote:normally, what would be the design of strap-ons, would they be derated or doubled up, just in case one fails, automatically shut/released and symmetrically opposite strap on could have shut down/released to equalize.. of course this can happen only if only 4 straps are required, and we go ahead add extra 4 more adjacent as standby.
!?
Can the motors be shut down once on full throttle?? Then again you need to sync the shut down commensurate with the momentum lost due to the failed strap-on, which I am assuming is very hard. Turning motor off, if that would be possible, is not a binary state: on and off. There is a transient state when the companion will still be producing thrust. But that increases the probability of vehicle going out of control regime. My estimate is such an additonal control overhead might not be commensurate with the benefits it delivers. Rather, can the strapons are design with some sort of flex-nozzle that might compensate for lack of momentum? No clue over that point.

The tradeoff between more strapons with less power v/s less number of strapons with more power is related to rocket mechanics and design objectives and I am total novice in that area. Gurus can shed light.
Last edited by Ananth on 13 Jul 2006 04:46, edited 1 time in total.
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Post by Arun_S »

Cross posting:

As I said before, the primary failure was when it was at 12 Km altitude, implying faliure of flight control system (hardware or software). The stage sepreation at >32Km problem is secondary symptom of the failure. There was yet another failure that I would rathur not comment.

'Agni-III's tracking control system failed'

http://timesofindia.indiatimes.com/arti ... 733336.cms
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Post by ramdas »

As I said before, the primary failure was when it was at 12 Km altitude, implying faliure of flight control system (hardware or software). The stage sepreation at >32Km problem is secondary symptom of the failure. There was yet another failure that I would rathur not comment.
1. Is the failure a failure of a fundamental kind, that might entail complete redesign from scratch, or something that can be fixed so that a new trial is held with a corrected version in the next few months ?

2. How would stage separation follow from a trajectory control failure ? If it is a open interstage, would the ignition of the second stage not automatically lead to stage separation ?

3. Is there a bar on ISRO scientists helping the DRDO people out on this ? That would certainly be a great help .

4. The Hindu reported that the propulsion system performance was satisfactory. If stage separation did not occur, is it not true that this can only be said about the first stage as far as this test is concerned ?
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Post by Ananth »

http://www.hindustantimes.com/news/181_ ... 040005.htm

Just for the record, posting in full:
The Indian Space Research Organisation on Wednesday formed a "failure analysis committee" to look into the unsuccessful flight on Monday of the Geosynchronous Satellite Launch Vehicle (GSLV) with the INSAT-4C satellite on board.

K Narayana, former director of SDSC-SHAR and currently Senior Advisor to the Centre, will chair the 15-member panel that includes experts from academic and research institutions besides officials from various ISRO centres.

The committee, formed by ISRO Chairman G Madhavan Nair, will review the performance of all sub-systems of GSLV from lift-off to termination of flight, identify specific reasons for anomalies and recommend corrective measures for future course of action, an ISRO statement said.

The committee is expected to submit its report in a month's time, it said.

About 60 seconds after its launch from the Satish Dhawan Space Centre (SDSC) at Sriharikota on Monday, the GSLV crashed into the Bay of Bengal. The rocket was destroyed after it veered off its trajectory.
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Post by Gerard »

Lessons to be learnt from Agni: Pranab
As reported earlier, the failure of the "tracking control system" of Agni-III, coupled with inability of the missile's second-stage to separate from the first, had led to the faulty test on Sunday.

"The actual cause of the snag will be known after the analysis of the detailed data obtained by Defence Research and Development Organisation (DRDO)," said Mukherjee.
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Post by karan »

Gerard wrote:Lessons to be learnt from Agni: Pranab
As reported earlier, the failure of the "tracking control system" of Agni-III, coupled with inability of the missile's second-stage to separate from the first, had led to the faulty test on Sunday.

"The actual cause of the snag will be known after the analysis of the detailed data obtained by Defence Research and Development Organisation (DRDO)," said Mukherjee.
Really...Mr Pranab. What lessons are you gonna learn. I thought all Indian politicians are the most learned people ever born on the face of this planet. They have learned all that was suppose to be learned! :lol:
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Post by Ananth »

link
Failure won’t affect future plans: VSSC director
Thursday July 13 2006 14:53 IST

THIRUVANANTHAPURAM: The failure of INSAT-4C will not affect the future programmes of the ISRO, including the GSLV launch scheduled for September and the moon mission, Vikram Sarabhai Space Centre director B N Suresh has said.

"It is a setback but we are well equipped to overcome this setback," Suresh told reporters at the airport here on his return from Sriharikota on Wednesday.

While claiming that failures in space launch programmes were not unusual, Suresh said that an expert committee had already been formed to find out the reason so that corrective measures could be taken. ‘‘A detailed investigation will reveal what went wrong,’’ he said.

Though the flight was allowed to go ahead as no technical lapse was found, from the data we see that there was a small malfunction in one of the regulators, which led to the automatic shutdown of the engine.

The investigation in detail about the hardware, system and pre-flight checks would bring out the reasons and they would help in taking corrective steps to improve the performance in future, Suresh said.
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Post by Arun_S »

Humm.....

That makes me think that the software certification program is deficient. Modern aero-Engine using FADC(Full Authority Digital Control) use a very strenuous programming methodology that ensures all exceptions converge to safe operation if the hardware is capable of and depending on the aircraft control mode. (Thus depending on mode certain excursion will be allowed, while in other modes safe shutdown is permissible).

In this case what the hell was the safe shutdown going to achieve!! (Bring the rocket back on launch pad?)And no one in the software code review and Software Quality Audit caught it.

I hope they invest more in building processes that gives extremely high reliability & robustness. Apart from building a more rigorous simulation test bed for software validation, and test plan that validated the system (not just engine component, but including flight control computer) for all possible single point of failures, and a selected set of 2 points of failure.


Knowing the exodus of software skills in high paying commercial jobs, I am very concerned about ISRO, DRDO and military ability to leverage local software skill to building and sustain complex software systems targeted at high integrity application like strategic missiles, space launcher/satellites, security application, command control and intelligence system etc. Not to speak of vanilla naval war-room :evil:
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Post by hnair »

Arun_S wrote:Humm.....

That makes me think that the software certification program is deficient. Modern aero-Engine using FADC(Full Authority Digital Control) use a very strenuous programming methodology that ensures all exceptions converge to safe operation if the hardware is capable of and depending on the aircraft control mode. (Thus depending on mode certain excursion will be allowed, while in other modes safe shutdown is permissible).

In this case what the hell was the safe shutdown going to achieve!! (Bring the rocket back on launch pad?)And no one in the software code review and Software Quality Audit caught it.
Good point about the futility of the shutdown - probably it is not just one logical point in the code that triggered the fatal shutdown. Maybe the software decision was a culmination of other faulty inputs eg: booster burn time might have been falsely reported to the decision point, making the shutdown appear normal. Sounds like a "perfect storm" situation for this flight.

But one really wishes that dint happen at this juncture, in our nation's path to higher levels.

About exodus of skills - Thank God for higher CPU speeds and automation, else a lot more of smart people would have been required even for routine ISRO work, both engineering and design......
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Post by Gerard »

From RaviBg's post in the agni-3 launch thread
The cause of the snag as reported to the Minister was that the Sunday test was carried for the two-stage missile with a booster but without changing the composition of the propellant.
It means that the propellant used for this test was similar to that used for Agni-II which has a range of hitting a target at 2,000 kms.
DDM ?
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Post by Ananth »

Gerard, this propellent composition thing is the second time Pioneer is reporting. From the post in this thread:
it was learnt here the snag may have developed because the test was carried out for the two-stage missile, 16 metre long and 1.8 metre in diameter, with a booster but without changing the composition of the propellant. Officials termed the snag as a design failure adding the missile failed to achieve the desired end objective.
This is the link to pioneer report.
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Post by Dileep »

Arun_S wrote:Humm.....

That makes me think that the software certification program is deficient.

In this case what the hell was the safe shutdown going to achieve!! (Bring the rocket back on launch pad?)And no one in the software code review and Software Quality Audit caught it.

Knowing the exodus of software skills in high paying commercial jobs...
The shutdown is correct action before the solid stage is ignited, and incorrect after. I know for a fact that this point is drilled down into the heads there. (Because it came up in all interviews I conducted. Yes, I did contribute to the exodus in a small way :oops: ) But that was several years ago. Dunno what happened now.

It was very interesting to see the religious zeal about the irreversibility of things in their field, especially, looking from the datacom area, where error and retry is the norm.
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Post by Dileep »

X from Agni thread:

I don't think the propellent is in question. I think what he refers to might be the explosive charge used for the stage seperation. If you use the system designed for a 1 metre dia shell on a 1.8 metre dia shell, that will not cut it.
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Post by Gerard »

But he mentions "specific impulse composition" implying the solid fuel itself ?

Perhaps he got this from a source inside DRDO/ISRO who was himself confused?
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Post by Dileep »

Perhaps he got this from a source inside DRDO/ISRO who was himself confused
Probably he got it from someone like a technician. That is pretty common with tech info.
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Post by Ananth »

http://www.hindu.com/2006/07/14/stories ... 901300.htm
"But we will study carefully" the failure of the GSLV-F02 (Geo-synchronous Satellite Launch Vehicle) flight from Sriharikota on July 10, Dr. Suresh said. For the strap-on engine propelled by liquid propellants that failed in the GSLV-F02 flight was also used in the PSLVs.

He described the failure of one of the four liquid strap-on engines of the

GSLV-F02 as "very unusual" and "a very strange case" because this engine had successfully performed in nine previous PSLV flights and three GSLV flights. Besides, this engine had been tested on the ground scores of times.

"We test the strap-ons repeatedly. Based on these tests only, we give the go." This liquid engine is called Vikas.

The GSLV-F02 flight failed on July 10 because pressure in one of its four strap-on engines, fuelled by liquid propellants, dropped to zero and the engine did not develop thrust. These strap-on engines are meant to augment the thrust of the GSLV. "Nowhere [earlier] have we faced this problem that we faced in this GSLV flight," the VSSC Director said.

One of the GSLV-F02's four strap-on engines shut down immediately after the core first stage of the vehicle, powered by solid fuel, was given ignition.

But with three other strap-on engines still functioning, the vehicle was under control for 35 to 40 seconds and "it still progressed," Dr. Suresh said. "So it was really a robust vehicle. If only that strap-on engine had performed, everything would have gone so well," he added.

After 40 to 50 seconds, it was under angle of attack. The vehicle was designed to withstand four degrees of angle of attack. But it came under ten degrees of angle of attack. In space parlance, an angle of attack refers to aerodynamic forces acting on the rocket. With ten degrees of angle of attack, the weight on the vehicle increased uncontrollably, Dr. Suresh said.

The vehicle was destroyed after about 60 seconds of flight.
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Post by gashish »

http://www.indiatoday.com/itoday/200607 ... html&SET=T

Setbacks In Space

The twin failures of the Agni III missile and the GSLV satellite launcher are a downturn for Indian rocketry and will cause delays in the plans of the country's two premier research organisations
By Raj Chengappa

The reactions to the failure by the two major scientific organisations are a study in contrast. DRDO decided to keep the causes of failure under wraps, making only a terse announcement that the Agni III test was "a partial success". No details were given out by the DRDO either about the specifications of the missile or what went wrong.

Experts reveal that for Agni III, the DRDO had designed and built an all-new rocket configuration as compared to the earlier versions. The missile was a stubby and much shorter version of Agni II, but packed almost twice the rocket power. DRDO had developed two new solid fuel motors that were being tested for the first time. It had also incorporated an advanced flex nozzle capability for guidance control. After the crash, DRDO appointed a failure review committee. The problem, it is learnt, occurred in the first stage itself, where a faulty component in the guidance system seemed to have thrown the missile off course and sent it hurtling into the Bay instead of its planned splash down in the Indian Ocean.

The Space Department though was far more open about its failure. Soon after the launch, ISRO Chairman G. Madhavan Nair bravely answered a barrage of media questions as to what went wrong. The chairman revealed that a malfunctioning strap-on motor on the first stage of the rocket had knocked the launcher totally off its calculated course (see graphic). Calling it "one of the rarest phenomena", Nair admitted that the mission failure was a "setback" for the organisation.

ISRO estimates the loss of both the launcher and the satellite to cost it around Rs 260 crore. A day later, a high-powered failure review committee was announced to go into all the data generated and report back speedily on what went wrong. Nair has promised the nation another launch of the GSLV within a year.
.
.
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Defence Minister Pranab Mukherjee, who witnessed the Agni III launch, told drdo scientists, quoting Bismarck: "One success will obscure all failures." It's a good adage for them to keep in mind as they identify the snags and shoot for the stars again.
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Post by bala »

Here comes the first concrete evidence - a part failure in the supply chain.

ISRO to tighten component quality audit

A minor flaw in a first stage engine component - made by a consortium and assembled by ISRO - may be to blame.

The GSLV-F02 disaster of July 10 will now bring all the industries that supplied to the launch vehicle programme under extra-rigorous quality scanner, according to an ISRO official.

Some 150 small, medium enterprises and large companies supply components and sub-systems for the launchers. The space agency sources its needs en bloc for two PSLVs and two GSLVs each year after thorough quality audits before each flight.

"This would have to be intensified and looked into microscopically, to perhaps even before the design stage. We are now in the process of reviewing all procedures and process documents to rule out any deviations. The teams are already there. We are right away getting into it," the official said.

The launch vehicle programme (LVP) is almost fully indigenous, with companies such as HAL, Tata, Godrej, L&T as regular participants. These and other industries have supplied ISRO's rockets, the Vikas rocket engines, motors, resistors, plumbing and other components.

As per ISRO's first assessments, one of the four strap-on motors proved a dud and drove the GSLV-F02 off the path at barely 15 km. For the first time, ISRO had to destroy the failed launcher along with the broadcast satellite Insat-4C.
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Post by Ananth »

http://www.financialexpress.com/fe_full ... _id=134249
[quote]
DRDO sources attributed the failure of the flight to the non-separation of the first stage from the second stage. “The launch did not meet all the mission requirements. A design failure is said to be the reason behind the non-separation of the first stage. Both the stages are powered by solid propellants,â€
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Post by Ananth »

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Post by Ananth »

India blames regulator for GSLV failure
Investigating the 10 July failure of its Geosynchronous Satellite Launch Vehicle (GSLV) soon after lift-off, the Indian Space Research Organisation (ISRO) says there was "a small malfunction in one of the regulators, which led to the automatic shutdown of the engines". The GSLV was carrying India's Insat 4-C communications satellite. The launcher was destroyed 60s after lift-off when it deviated off course after pressure in one of the liquid-propellant strap-on stages dropped to zero. This was the first time the first stage of GSLV has failed in flight, says ISRO.
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Post by Ananth »

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Post by p_saggu »

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Post by narmad »

http://www.hindustantimes.com/news/5922 ... 000000.htm

Robot and three ships search for rocket debris to find clues to July 10 explosion, and learn lessons for future space missions.

WHAT EXACTLY led to the failure of the Geosynchronous Satellite Launch Vehicle mission on July 10? A team of oceanographers and professional divers — assisted by a robot — are searching for clues in the Bay of Bengal to help space scientists answer that.

The 414-tonne GSLV-FO2 (with a piggyback load of the INSAT 4C communication satellite) had veered 10 degrees off course and had to be exploded 15 km above the sea seconds after its launch. The blame was put on one of its strap-on engines that failed. Nobody knows why it failed.

Space scientists were asked to probe into it and a hastily formed team was instructed by the ISRO to scout for the remains of the engines and strap-on motors so that they can be examined.

The under-sea operation off the Sriharikota coast near Chennai, which started four days ago, reported its first find on Saturday. Experts on board the ocean research vessel Sagar Kanya sent word to Delhi that they had located and hauled one of the four strap-on engines.

P.S. Goel, secretary, Department of Ocean Development, Delhi, told HT: “One of the four strap-on engines has been recovered. But it may not be the one that failed.â€
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Post by SaiK »

a small malfunction in one of the regulators, which led to the automatic shutdown of the engines".
so what.. it should have released those shut down engines.. may be the failure there. if its an explosion, then it could be the failure of the shutdown itself.

btw, lets say two engines have been release due to failure. does the gslv has enough power to reach the orbit? would not be failure still?
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Post by Katare »

Sai,

You should read a bit more....all the information is with in this thread alone.
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Post by SaiK »

...yeah... i would wish to have the payload safely parachuted down, if its a "command" design to destruct it. anyway, hope for that in the future designs, so that we can retrieve and resend the mission on another launch vehicle.
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Post by Cybaru »

All those proponents of involving private industry are going to get spanked by the other camp, when the gslv report comes out.
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Post by Gerard »

One GSLV strap-on motor recovered from sea
"We are yet to locate the failed engine," he said on Monday from Bangalore.

"We are hopeful we will recover it in the course of this week. We have a certain hypothesis [on why the flight failed]. If we can recover the failed engine, it will be an added input. It will be definitely an invaluable input."
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Post by negi »

SaiK wrote:normally, what would be the design of strap-ons, would they be derated or doubled up, just in case one fails, automatically shut/released and symmetrically opposite strap on could have shut down/released to equalize.. of course this can happen only if only 4 straps are required, and we go ahead add extra 4 more adjacent as standby.

!?
Extra four strap ons as stand by you know how much takes to loft a Kg of mass in Geostaionary orbit.And by the way that system wont work on a complex system as a rocket.
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We should not loose heart

Post by negi »

Contrary to most of Indian PSU's ISRO is the one that has always been a example of Pride and self reliance in India's quest of becoming a global leader.The GSLV crash incident shouldnt affect the morale of the scientists and general public per se.Even US and RUSSIA world's leading space powers have experienced such hick ups.I am eagerly waiting for the next GSLV launch. :D
ramana
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Post by ramana »

It is incorrect to club the two failures together for the following reasons.
Political: The GSLV is a civilian launch vehicle and the Agni is a military vehicle. There are firewalls between ISRO and DRDO despite the early Agni boosters being based on SLV first stage. Per U.R. Rao communicating to Al Gore in 1993, more ISRO employees have joined NASA and the US space industry than DRDO.
Technical: The GSLV failure root cause is a trivial one and has been already traced to poor quality control. The Agni failure is more challenging to identify with out insight into the actual technical details.
However since the thread has been started early one let it remain.

Any scenario to describe the AIII anomaly has to take into account the following facts as reported in the press:
The early description of test success based on splashdown observed by down range ships at Car Nicobar. So has to take into account the great circle distance between Chandipur and Car Nicobar and later reported less than 1000 km splashdown.
It has to account for the height (apogee) of ~ 150 km. Add to that the info about events at altitudes of 12km and 50 km and lack of stage separation. There were reports of tracking control system issues which contributed to the overall underperformance. I am sure Arun will step up with his analysis.
Ananth
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Post by Ananth »

ramana wrote: The early description of test success based on splashdown observed by down range ships at Car Nicobar.
I missed/overlooked the press report citing that splashdown around 1000 kms offshore was the cause of pre-mature celebration. The reports i read said the initial jubiliation at the control room was due to perfect liftoff which turned to gloom when the missile lost control. Why would there be a celebration when the range achieved was 1/3rd? Can you cite the report which said that?
Arun_S
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Post by Arun_S »

Ananth: Just a friendly note. Please try to read first few pages of the Agni-III thread, you will get the reference there.

Ramana: Sure. I am bit sleepy now with all the hard work, will share results in about 10 hrs.
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