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How Isro got an indigenous cryogenic engine
Mission director K. Sivan kept his fingers firmly crossed in the mission control room at the Indian Space Research Organisation (Isro) Satish Dhawan Space Centre in Sriharikota on the morning of 5 January as the moment drew closer for the launch of the Geosynchronous Satellite Launch Vehicle, or GSLV-D5.
The rocket, powered by India’s indigenous cryogenic engine, had been tested and reviewed numerous times in the four months since its aborted launch on 19 August due to a crack in the fuel tank. After the 5 January launch, every step that the rocket cleared made Sivan a happier man. But he also became more anxious—after all, of the seven GSLV launches earlier, five had failed. It was only when the satellite GSAT-14 onboard the GSLV-D5 was inserted into a precise orbit that Sivan relaxed. “It was like the rebirth of GSLV,” he said.
The search for cryogenic engine
The GSLV programme was started by Isro in response to India’s mounting communications needs. By 1987, the government had approved the development of the second generation INSAT-2 series of satellites, weighing more than 2 tonnes. Isro wanted to develop a 2.5-tonne class of satellites and put them into a geostationary transfer orbit at 36,000km from Earth’s surface.
Isro also wanted to make a vehicle that would be bigger, lighter and more efficient than its workhorse Polar Satellite Launch Vehicle (PSLV). There were three fuels options: earth storable, semi-cryogenic, and cryogenic.
Cryogenic engines, which use liquid hydrogen and liquid oxygen as fuel and give the most thrust, are usually prepared for the “upper stages”—the last stage of the rocket—because this stage provides 50% of the velocity of 10.2km per second needed at the point of injection of a satellite. In 1986, at a cost of Rs.12 crore, Isro scientists began developing a one-tonne cryogenic engine to try and understand how to handle liquid hydrogen and liquid oxygen. At the same time, a design team was formed at Isro’s Liquid Propulsion Centre at Mahendragiri in Tamil Nadu to come up with the design of a seven-tonne turbo-fed engine. Although this development boosted the confidence of Isro engineers, Isro knew that it couldn’t wait much longer to develop the indigenous engine.
The Russian deal
It was then that Isro thought of procuring cryogenic engines from other countries. After rejecting offers from the US and France for both the sale of engines and transfer of technology, India approved an offer by the Soviet Union’s Glavkosmos space agency in 1990. India sent eight scientists to Moscow to work with Soviet scientists. They worked there for 15 months, but did not have access to everything.
“The Russians were very secretive about everything, even though they had signed the technology transfer agreement. Discussions were limited, and the Indian scientists were never allowed to walk the labs freely; they needed clearance to move around the lab,” said B.N. Suresh, former director, Vikram Sarabhai Space Centre in Thiruvananthapuram. “Hence they couldn’t learn very much.”
Then, 15 months after the deal was signed, the US raised objections citing a violation of the international Missile Technology Control Regime (MTCR). The West feared that cryogenic technology could be used by India to develop intercontinental ballistic missiles, which is rejected by Indian scientists.
Eventually, in 1993, Glavkosmos backed out of the deal and revoked the transfer of cryotechnology agreement. Under a renegotiated deal, Russia decided to provide four fully functional engines and two mock-ups. It also agreed to supply three more cryogenic engines at a cost of $9 million.
At this point, the Space Commission, which formulates and implements the Indian space programme, approved a Rs.280 crore project to develop an Indian cryogenic engine, the C12.
“We had to get back our people who were already working with the Russian scientists. Then we had to start on our own. They had made some sorts of drawings and designs and they were already working on the engines and fabrication processes with the Russian scientists,” said U.R. Rao, former chairman at Isro. “But still, many things cannot be on paper since there are various processes we go through to make every step as accurate as possible.”
Practical steps
Preparations were made for the first developmental flight of the GSLV-D1 with a procured Russian cryogenic third stage, planned for early 2001. A cryogenic upper stage (CUS) project had also speeded up the design and development of an indigenous engine to replace the Russian one.
“A lot of theoretical studies were conducted under E.V.S. Namboodiry, a propulsion expert who was in charge of studying the cryogenic engine with a team of experts. Something like 18 reports came out regarding cryogenic engine. But theories cannot give you a stage,” said Suresh.
Isro scientists had to become adept in areas such as materials technology, powder metallurgy, welding technology and fabrication technology.
2009-14: Road to success
Even as scientists gained experience from GSLV launches with a Russian cryogenic upper stage engine, they worked feverishly on the indigenous version. In 2009, Isro concentrated on developing infrastructure like the propellant casting facility for solid boosters. That year, Isro reached a landmark when the indigenous cryogenic engine was tested at the Mahendragiri and cleared for a full flight.
But the launch of the flight—the first with an indigenous engine—the GSLV-D3 in April 2010, with a GSAT-4 satellite on board, failed.
The rocket deviated from its path and the vehicle was seen “tumbling” down by Isro scientists. “The thing with rocket launches is that there is not much difference between success and failure. We succeeded (in 2014), but a tiny glitch and we could have ended up in the Bay of Bengal,” said R.V. Perumal, former director of the GSLV project.
The failure, a major disappointment to the nation, was caused by the fact that the cryogenic upper stage could not sustain ignition because the fuel booster turbo pump stopped working 293 seconds into the flight. The second developmental launch of the GSLV D-3 in December 2010 ended in an explosion due to a technical snag in the first stage.
“After the first failure (in 2010), the problem was that we could not recreate the cause of the failure, so it was hard to correct the problem,” said Sivan. “So we listed out possible failures, all feasible reasons for the stopping of fuel booster pump, and took corrective actions for all of them.”
“Even though we would test the engine and the ignition sequence on the ground, the conditions on the flight would be much different,” said Sivan. For Isro, it now became necessary to create those conditions for testing. A high altitude test facility was built in Mahendragiri in 2012 to demonstrate successful ignition for simulated flight conditions. And after testing the system in those conditions, Isro modified the ignition sequence.
Still, in August 2013, a GSLV-D5 launch was aborted at the eleventh hour after a leak was detected in the fuel booster pump. After decades of dogged engineering pursuit, this was an easier problem to solve for Isro.
“When we went ahead with the flight after testing the engine in every possible condition, we were confident of success. We had arrived,” said Sivan.
How Isro got an indigenous cryogenic engine | idrw.org
Mission director K. Sivan kept his fingers firmly crossed in the mission control room at the Indian Space Research Organisation (Isro) Satish Dhawan Space Centre in Sriharikota on the morning of 5 January as the moment drew closer for the launch of the Geosynchronous Satellite Launch Vehicle, or GSLV-D5.
The rocket, powered by India’s indigenous cryogenic engine, had been tested and reviewed numerous times in the four months since its aborted launch on 19 August due to a crack in the fuel tank. After the 5 January launch, every step that the rocket cleared made Sivan a happier man. But he also became more anxious—after all, of the seven GSLV launches earlier, five had failed. It was only when the satellite GSAT-14 onboard the GSLV-D5 was inserted into a precise orbit that Sivan relaxed. “It was like the rebirth of GSLV,” he said.
The search for cryogenic engine
The GSLV programme was started by Isro in response to India’s mounting communications needs. By 1987, the government had approved the development of the second generation INSAT-2 series of satellites, weighing more than 2 tonnes. Isro wanted to develop a 2.5-tonne class of satellites and put them into a geostationary transfer orbit at 36,000km from Earth’s surface.
Isro also wanted to make a vehicle that would be bigger, lighter and more efficient than its workhorse Polar Satellite Launch Vehicle (PSLV). There were three fuels options: earth storable, semi-cryogenic, and cryogenic.
Cryogenic engines, which use liquid hydrogen and liquid oxygen as fuel and give the most thrust, are usually prepared for the “upper stages”—the last stage of the rocket—because this stage provides 50% of the velocity of 10.2km per second needed at the point of injection of a satellite. In 1986, at a cost of Rs.12 crore, Isro scientists began developing a one-tonne cryogenic engine to try and understand how to handle liquid hydrogen and liquid oxygen. At the same time, a design team was formed at Isro’s Liquid Propulsion Centre at Mahendragiri in Tamil Nadu to come up with the design of a seven-tonne turbo-fed engine. Although this development boosted the confidence of Isro engineers, Isro knew that it couldn’t wait much longer to develop the indigenous engine.
The Russian deal
It was then that Isro thought of procuring cryogenic engines from other countries. After rejecting offers from the US and France for both the sale of engines and transfer of technology, India approved an offer by the Soviet Union’s Glavkosmos space agency in 1990. India sent eight scientists to Moscow to work with Soviet scientists. They worked there for 15 months, but did not have access to everything.
“The Russians were very secretive about everything, even though they had signed the technology transfer agreement. Discussions were limited, and the Indian scientists were never allowed to walk the labs freely; they needed clearance to move around the lab,” said B.N. Suresh, former director, Vikram Sarabhai Space Centre in Thiruvananthapuram. “Hence they couldn’t learn very much.”
Then, 15 months after the deal was signed, the US raised objections citing a violation of the international Missile Technology Control Regime (MTCR). The West feared that cryogenic technology could be used by India to develop intercontinental ballistic missiles, which is rejected by Indian scientists.
Eventually, in 1993, Glavkosmos backed out of the deal and revoked the transfer of cryotechnology agreement. Under a renegotiated deal, Russia decided to provide four fully functional engines and two mock-ups. It also agreed to supply three more cryogenic engines at a cost of $9 million.
At this point, the Space Commission, which formulates and implements the Indian space programme, approved a Rs.280 crore project to develop an Indian cryogenic engine, the C12.
“We had to get back our people who were already working with the Russian scientists. Then we had to start on our own. They had made some sorts of drawings and designs and they were already working on the engines and fabrication processes with the Russian scientists,” said U.R. Rao, former chairman at Isro. “But still, many things cannot be on paper since there are various processes we go through to make every step as accurate as possible.”
Practical steps
Preparations were made for the first developmental flight of the GSLV-D1 with a procured Russian cryogenic third stage, planned for early 2001. A cryogenic upper stage (CUS) project had also speeded up the design and development of an indigenous engine to replace the Russian one.
“A lot of theoretical studies were conducted under E.V.S. Namboodiry, a propulsion expert who was in charge of studying the cryogenic engine with a team of experts. Something like 18 reports came out regarding cryogenic engine. But theories cannot give you a stage,” said Suresh.
Isro scientists had to become adept in areas such as materials technology, powder metallurgy, welding technology and fabrication technology.
2009-14: Road to success
Even as scientists gained experience from GSLV launches with a Russian cryogenic upper stage engine, they worked feverishly on the indigenous version. In 2009, Isro concentrated on developing infrastructure like the propellant casting facility for solid boosters. That year, Isro reached a landmark when the indigenous cryogenic engine was tested at the Mahendragiri and cleared for a full flight.
But the launch of the flight—the first with an indigenous engine—the GSLV-D3 in April 2010, with a GSAT-4 satellite on board, failed.
The rocket deviated from its path and the vehicle was seen “tumbling” down by Isro scientists. “The thing with rocket launches is that there is not much difference between success and failure. We succeeded (in 2014), but a tiny glitch and we could have ended up in the Bay of Bengal,” said R.V. Perumal, former director of the GSLV project.
The failure, a major disappointment to the nation, was caused by the fact that the cryogenic upper stage could not sustain ignition because the fuel booster turbo pump stopped working 293 seconds into the flight. The second developmental launch of the GSLV D-3 in December 2010 ended in an explosion due to a technical snag in the first stage.
“After the first failure (in 2010), the problem was that we could not recreate the cause of the failure, so it was hard to correct the problem,” said Sivan. “So we listed out possible failures, all feasible reasons for the stopping of fuel booster pump, and took corrective actions for all of them.”
“Even though we would test the engine and the ignition sequence on the ground, the conditions on the flight would be much different,” said Sivan. For Isro, it now became necessary to create those conditions for testing. A high altitude test facility was built in Mahendragiri in 2012 to demonstrate successful ignition for simulated flight conditions. And after testing the system in those conditions, Isro modified the ignition sequence.
Still, in August 2013, a GSLV-D5 launch was aborted at the eleventh hour after a leak was detected in the fuel booster pump. After decades of dogged engineering pursuit, this was an easier problem to solve for Isro.
“When we went ahead with the flight after testing the engine in every possible condition, we were confident of success. We had arrived,” said Sivan.
How Isro got an indigenous cryogenic engine | idrw.org
Bhasad Singh Mundi
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Gagan System to Save $10 mn a Year on Fuel Costs
'Gagan System to Save $10 mn a Year on Fuel Costs' -The New Indian Express
'Gagan System to Save $10 mn a Year on Fuel Costs' -The New Indian Express
Bhasad Singh Mundi
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Successful testing of Parachute Recovery System for Human Space Programme
Aerial Delivery Research and Development Establishment (ADRDE), Agra, successfully conducted testing of Parachute Recovery System for Human Space Programme of Indian Space Research Organisation (ISRO) on 18 January 2014 by para dropping simulated load weighing 5 ton against actual system requirement of 3.6 ton at Agra Drop Zone using IL-76 Aircraft.
The trial preceded a series of eight successful sub-systems level air-drop tests from AN-32 aircraft. The system has been designed for safe landing of a crew module of 3.6 ton weight class on sea surface. The recovery system consists of a pilot parachute, a drogue parachute and a main parachute.
In this simulated test, with integrated parachute system, the simulated load was extracted from IL-76
aircraft by extractor parachute. Subsequently a drogue parachute was deployed which in turn deployed the
main parachute. This test successfully verified the sequence of parachute deployment, configuration of the
parachute, deployment bag and other sub-systems using onboard instrumentation. ADRDE has also successfully demonstrated this technology by recovering a 500 kg class actual module for ISRO in 2007. The successful test was backed by various technologies, viz., high performance textiles, aerodynamic design, configuration optimisation, fabrication, integration, testing, validation, etc.
kurup
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ANU ties up with ISRO for radar design
Acharya Nagarjuna University will now partner Satish Dhawan Space Centre (SDSC)-SHAR, Indian Space Research Organisation (ISRO) in designing a Multi Object Tracking Radar (MOTR) to be used in defence surveillance.
Vice-Chancellor K. Viyanna Rao said on Friday that ANU has entered into a Memorandum of Understanding with SDSC-SHAR to design the MOTR, becoming the first university in the country to have a tie-up with SDSC-SHAR in designing indigenous radars. India is the fourth nation in the world, after the US, Japan and Germany to design MOTRs, he said.
MoU signed
Associate Director of SHAR and Project Director, MOTR, V. Seshagiri Rao signed the MoU with Dean of ANU Engineering College and principal investigator of the project, P. Siddaiah.
“Conventional radars are designed to track one object but the MOTR is being designed to track multiple objects simultaneously from a distance of 1,000 km. It is also used in tracking the path of satellites in various stages,” said Dr. Siddaiah.
A first
The radar, the first-of-its-kind in the country, is being designed with 4,600 antennas at a cost of Rs.253 crore.
Dr. Siddaiah said the university would provide high frequency structural simulator software for designing the radar. The ISRO had allotted three research fellows and one technical officer, besides a grant of Rs.28 lakh to execute the project.
It is being designed to track multiple objects from a distance of 1,000 km .
ANU ties up with ISRO for radar design | idrw.org
Acharya Nagarjuna University will now partner Satish Dhawan Space Centre (SDSC)-SHAR, Indian Space Research Organisation (ISRO) in designing a Multi Object Tracking Radar (MOTR) to be used in defence surveillance.
Vice-Chancellor K. Viyanna Rao said on Friday that ANU has entered into a Memorandum of Understanding with SDSC-SHAR to design the MOTR, becoming the first university in the country to have a tie-up with SDSC-SHAR in designing indigenous radars. India is the fourth nation in the world, after the US, Japan and Germany to design MOTRs, he said.
MoU signed
Associate Director of SHAR and Project Director, MOTR, V. Seshagiri Rao signed the MoU with Dean of ANU Engineering College and principal investigator of the project, P. Siddaiah.
“Conventional radars are designed to track one object but the MOTR is being designed to track multiple objects simultaneously from a distance of 1,000 km. It is also used in tracking the path of satellites in various stages,” said Dr. Siddaiah.
A first
The radar, the first-of-its-kind in the country, is being designed with 4,600 antennas at a cost of Rs.253 crore.
Dr. Siddaiah said the university would provide high frequency structural simulator software for designing the radar. The ISRO had allotted three research fellows and one technical officer, besides a grant of Rs.28 lakh to execute the project.
It is being designed to track multiple objects from a distance of 1,000 km .
ANU ties up with ISRO for radar design | idrw.org
kurup
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Missing jet: Isro awaits govt nod to deploy space assets
With sleuths probing the disappearance of Malaysian Airlines flight MH370 bound for Beijing from Kuala Lumpur having proposed that the aircraft could have crashed in the Bay of Bengal or somewhere in the deep southern side of the Indian ocean, the Indian Space Research Organisation (Isro) might assist in the search for the plane.
Top Isro officials told Deccan Herald: “Isro would be ready to assist in the search if the highest authority in the country asks it to do so, and also if a specific request comes from Malaysia, again subject to approval of the Government of India.”
Asked who the competent authority would be to permit Isro to deploy its space assets, the officials said, “It would be the people in charge of space. This may include in the least the prime minister, the Isro chairman and the Department of Space secretary. There may also be consultations with other important people of the government.”
The officials added that India is a signatory to the International Treaty on Space and Disasters—a worldwide charter for sharing satellite transmission with countries and agencies involved in humanitarian work in the wake of disasters.
Whatever inputs the satellites get, they would be shared with co-signatories to the treaty, which came up in 2000 due to initiatives taken by the European Space Agency (ESA) and the French Space Agency CNES. The disasters could be any kind—earthquake, tsunami, oil spill, hurricane, landslide, excessive snowfall, floods, volcanic eruption, etc.
“Members of this treaty can invoke it and forward a request for sharing information from satellites to help mitigate the disaster. But the only issue is whether a plane crash can be defined as a disaster in terms of natural disasters like earthquakes and floods. That’s a call the member countries will have to take. This will involve discussions and consultations, but countries may not be very strict when it comes to a crisis like a plane crash.”
Missing jet: Isro awaits govt nod to deploy space assets | idrw.org
With sleuths probing the disappearance of Malaysian Airlines flight MH370 bound for Beijing from Kuala Lumpur having proposed that the aircraft could have crashed in the Bay of Bengal or somewhere in the deep southern side of the Indian ocean, the Indian Space Research Organisation (Isro) might assist in the search for the plane.
Top Isro officials told Deccan Herald: “Isro would be ready to assist in the search if the highest authority in the country asks it to do so, and also if a specific request comes from Malaysia, again subject to approval of the Government of India.”
Asked who the competent authority would be to permit Isro to deploy its space assets, the officials said, “It would be the people in charge of space. This may include in the least the prime minister, the Isro chairman and the Department of Space secretary. There may also be consultations with other important people of the government.”
The officials added that India is a signatory to the International Treaty on Space and Disasters—a worldwide charter for sharing satellite transmission with countries and agencies involved in humanitarian work in the wake of disasters.
Whatever inputs the satellites get, they would be shared with co-signatories to the treaty, which came up in 2000 due to initiatives taken by the European Space Agency (ESA) and the French Space Agency CNES. The disasters could be any kind—earthquake, tsunami, oil spill, hurricane, landslide, excessive snowfall, floods, volcanic eruption, etc.
“Members of this treaty can invoke it and forward a request for sharing information from satellites to help mitigate the disaster. But the only issue is whether a plane crash can be defined as a disaster in terms of natural disasters like earthquakes and floods. That’s a call the member countries will have to take. This will involve discussions and consultations, but countries may not be very strict when it comes to a crisis like a plane crash.”
Missing jet: Isro awaits govt nod to deploy space assets | idrw.org
kurup
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CSIR-NAL's contribution to the GSLV-D5 programme
The Indigenous Cryogenic Upper Stage was successfully flight-tested onboard GSLV-D5 launch vehicle on January 05, 2014 from Satish Dhawan Space Centre SHAR, Sriharikota. In this successful flight of GSLV-D5, a communication satellite - GSAT-14 - was launched very precisely to its intended Geosynchronous Transfer Orbit. CSIR-NAL is proud to have been associated with the programme. A gist of the contribution made from CSIR-NAL is outlined here.
Contributions from NTAF for the GSLV D5 configuration
In year 2010 after GSLV failure, VSSC came up with an urgent requirement of unsteady pressure measurements in ITS region with simulated wire tunnels for post – flight failure analysis. One of the force models was modified for the above studies and results were supplied in a month’s time which has given a valuable input to the project.
Later in year 2011, it was decided to complete aerodynamic re-characterization of the GSLV D5 vehicle with fully simulated wind tunnel model. The major challenge was to design, manufacture and test models for force measurements, steady and unsteady pressure measurements in a very short time frame. It was decided to design the models at CSIR-NAL and manufactured at VSSC. The design project team worked in two shifts and completed the design of three models and model components were manufactured at VSSC within a record time. Final assembly of the force model, instrumentation of about 160 pressure ports on steady and about 45 unsteady pressure ports on models were carried out at CSIR-NAL. To complete aerodynamic characterization of the vehicle about 1000 runs were carried out on the complete force model, truncated unsteady and steady pressure in CSIR-NAL 0.6m and 1.2m wind tunnels. For detailed unsteady pressure measurements, the existing 24-channel high-speed data acquisition and processing system was upgraded to 48-channel system and about 80 runs were conducted. For steady-pressure measurements on GSLV model of about 150 pressure ports were instrumented. All these activities were carried out within a record time.
V Nagarajan
CSIR-NAL ATF & ISRO's GSLV programme
ATF at NAL has been involved in the dynamic environment qualification of stages, subsystems and components from the very beginning of the GSLV programme. 30 major acoustic test programmes on the GSLV were completed at ATF, spreading over the years 1995 to 2013 with a total of 515 blowdowns. Considering the fact that ATF conducts acoustic tests on full scale launch vehicle hardware with some of the hardware being actual systems used for flight, this has been a mammoth task. The GSLV Heat Shield – both metallic as well as CFRP, the Core base shroud, the 1/2 & 2/3 interstages, the strapon nosecones, the L40 engine bay and the strapon nosecone avionic decks are the major stages/subsystems qualified at ATF. The earlier GSLV launches used the Russian cryogenic stages and hence these stages did not undergo acoustic tests at ATF. During the initial acoustic test programmes at ATF on GSLV subsystems, several vital design issues were detected , fixes incorporated and retested. It is worth noting that for each flight of the GSLV, several flightworthy subsystems, such as the Strap on Nose Cone and the avionic decks of each of the strapon boosters underwent acoustic tests at ATF.
ATF has established an excellent work culture in tune with the requirements of ISRO for providing seamless support for the acoustic qualification of the GSLV. Necessary infrastructure has been established for the purposes of handling , assembly, instrumentation, testing and post test inspections of the large sized test specimen. The infrastructure at ATF has been continuously evolving to keep pace with the increasing size of the test specimen. For the GSLV programmes, ATF has added additional unloading and assembly areas which have helped meet the requirements of bigger sized test specimen. The GSLV programme required ATF to develop certain highly unconventional test methodologies. In the initial days of the GSLV cryogenic stage development programme, designers required to test the homogeneity of the temperature insulating material which was bonded to the the shell of the cryo stage under acoustic loads. The challenge was to simulate the acoustic environment and at the same time, simulate,the low temperatures which the cryo stage shell would have to endure and maintain a homogenous bond. ATF provided a very unconventional test methodology which allowed simulation of the required low temperatures with liquid nitrogen and generation of the acoustic levels to which the panel would be subjected (see image above).
This test provided valuable inputs to the VSSC and LPSC teams involved in the design of the indigenous cryogenic stage. Several such “unconventional” acoustic tests continued throughout the GSLV qualification programme and over the last year, the indigenous cryo engine/stage subsystems underwent a number of these tests, the results of which were very closely linked to the actual integration of the flight stage. It is very heartening to note that the results / observations of the acoustic tests conducted on several subsystems of the cryo stage at ATF had a direct impact on the integration and assembly processes of the stage. In addition, changes incorporated in the assembly processes of the stage were also being verified for integrity under acoustic loading. For such acoustic tests, very high acoustic levels of the order of 164 dB were required to excite very localized areas on the specimen. The wire tunnel , umbilical connector units , the cryo stage vent valves , the LH2 vent and relief line and the protection plates in the ITT region were required to be subjected to such localized, high acoustic levels.In order to provide such high acoustic levels, ATF had to carry out extensive mapping of acoustic amplitude and frequency in the immediate vicinity of the exponential horns and provide specimen mounting interfaces at these locations . This work needed to be carried out in almost real time since the test requirements were continuously changing based on various considerations and recommendations of test and evaluation committees. The image below shows the wire tunnel of the cryo stage mounted at a height of 11.5 metres near the 25 Hz exponential horn to carry out an acoustic test at a level of 164 dB at low frequencies. A similar test was also conducted on the umbilical connector unit which houses the interfaces (both electrical as well as cryo fuel) between the launch pedestal and the cryogenic stage. The entire umbilical connector unit assembly was also acoustic tested near the 25 Hz horn at 11.5 metres height. The series of acoustic tests also involved assembly of the wire tunnel and the umbilical connector unit , as on the flight stage and testing the combination near the 80 / 160 Hz horns of ATF at levels of 162 dB. The test sequence involved , simulation of a variety of fastening techniques and also the use of teflon, metallic inserts and washers to determine torque retention in the fastened assemblies. The results of these tests played a major role in the finalization of fastening techniques for a large number of assemblies. Tests were also carried out on the carbon composite cover plates used in the inter tank truss region of the cryo stages to provide protection to the various gas line interfaces located there. An acoustic test was also carried out on the Liquid Hydrogen Vent Pipe and the vent valve assembly. This is also a very crucial subassembly of the cryogenic stage.
A major acoustic test programme involved tests on a subassembly of the cryogenic stage consisting of the liquid oxygen tank, the lower shroud covering the the truss region, truncated main cryogenic engine, the steering engine, the wire tunnel in the tank and shroud portion, the Inter Stage 2/3L and the separation plane connectors. The principal purpose of this test was to determine the integrity of the shroud, verify separation connector mating status and to determine the induced vibration response for the specified acoustic loading. This test was conducted at 156 dB. This test simulated , redesigned and upgraded hardware to overcome issues in the unsuccessful GSLV-F06 flight where the lower shroud failed and the separation plane connectors snapped leading to loss of connectivity and subsequent destruction of the vehicle from ground.
ATF has designed and fabricated unique test fixtures for all the GSLV test programmes. Since the test specimen are all unique, suitable fixtures and interfaces to mount the test specimen on the existing specimen trolley at ATF require to be designed, load tested and approved by a combined ATF-VSSC test and evaluation team , before being used for the actual tests.
The ATF team has also significantly contributed to the several Environmental Test Level Committees, Test and Evaluation Committees and other forum in ISRO which decide the acoustic test specifications as well as the test configuration , test sequence and inspection parameters.
Most of the acoustic test programmes mentioned were specifically for the GSLV-D5 mission. The extensive test programmes spread over the last year and a half catered to the redesign and qualification of major subsystems and assemblies of the indigenous cryogenic stage. The team at ATF is proud to be associated with ISRO’s GSLV programme and the years of dedication and hard work , sometimes stretching over months with very little personal time has ultimately paid off with the hugely successful flight of the GSLV-D5 and the excellent performance of the indigenous cryogenic engine.
K N Arun Kumar
NAL-Information Pasteboard
From D-F-I
The Indigenous Cryogenic Upper Stage was successfully flight-tested onboard GSLV-D5 launch vehicle on January 05, 2014 from Satish Dhawan Space Centre SHAR, Sriharikota. In this successful flight of GSLV-D5, a communication satellite - GSAT-14 - was launched very precisely to its intended Geosynchronous Transfer Orbit. CSIR-NAL is proud to have been associated with the programme. A gist of the contribution made from CSIR-NAL is outlined here.
Contributions from NTAF for the GSLV D5 configuration
In year 2010 after GSLV failure, VSSC came up with an urgent requirement of unsteady pressure measurements in ITS region with simulated wire tunnels for post – flight failure analysis. One of the force models was modified for the above studies and results were supplied in a month’s time which has given a valuable input to the project.
Later in year 2011, it was decided to complete aerodynamic re-characterization of the GSLV D5 vehicle with fully simulated wind tunnel model. The major challenge was to design, manufacture and test models for force measurements, steady and unsteady pressure measurements in a very short time frame. It was decided to design the models at CSIR-NAL and manufactured at VSSC. The design project team worked in two shifts and completed the design of three models and model components were manufactured at VSSC within a record time. Final assembly of the force model, instrumentation of about 160 pressure ports on steady and about 45 unsteady pressure ports on models were carried out at CSIR-NAL. To complete aerodynamic characterization of the vehicle about 1000 runs were carried out on the complete force model, truncated unsteady and steady pressure in CSIR-NAL 0.6m and 1.2m wind tunnels. For detailed unsteady pressure measurements, the existing 24-channel high-speed data acquisition and processing system was upgraded to 48-channel system and about 80 runs were conducted. For steady-pressure measurements on GSLV model of about 150 pressure ports were instrumented. All these activities were carried out within a record time.
V Nagarajan
CSIR-NAL ATF & ISRO's GSLV programme
ATF at NAL has been involved in the dynamic environment qualification of stages, subsystems and components from the very beginning of the GSLV programme. 30 major acoustic test programmes on the GSLV were completed at ATF, spreading over the years 1995 to 2013 with a total of 515 blowdowns. Considering the fact that ATF conducts acoustic tests on full scale launch vehicle hardware with some of the hardware being actual systems used for flight, this has been a mammoth task. The GSLV Heat Shield – both metallic as well as CFRP, the Core base shroud, the 1/2 & 2/3 interstages, the strapon nosecones, the L40 engine bay and the strapon nosecone avionic decks are the major stages/subsystems qualified at ATF. The earlier GSLV launches used the Russian cryogenic stages and hence these stages did not undergo acoustic tests at ATF. During the initial acoustic test programmes at ATF on GSLV subsystems, several vital design issues were detected , fixes incorporated and retested. It is worth noting that for each flight of the GSLV, several flightworthy subsystems, such as the Strap on Nose Cone and the avionic decks of each of the strapon boosters underwent acoustic tests at ATF.
ATF has established an excellent work culture in tune with the requirements of ISRO for providing seamless support for the acoustic qualification of the GSLV. Necessary infrastructure has been established for the purposes of handling , assembly, instrumentation, testing and post test inspections of the large sized test specimen. The infrastructure at ATF has been continuously evolving to keep pace with the increasing size of the test specimen. For the GSLV programmes, ATF has added additional unloading and assembly areas which have helped meet the requirements of bigger sized test specimen. The GSLV programme required ATF to develop certain highly unconventional test methodologies. In the initial days of the GSLV cryogenic stage development programme, designers required to test the homogeneity of the temperature insulating material which was bonded to the the shell of the cryo stage under acoustic loads. The challenge was to simulate the acoustic environment and at the same time, simulate,the low temperatures which the cryo stage shell would have to endure and maintain a homogenous bond. ATF provided a very unconventional test methodology which allowed simulation of the required low temperatures with liquid nitrogen and generation of the acoustic levels to which the panel would be subjected (see image above).
This test provided valuable inputs to the VSSC and LPSC teams involved in the design of the indigenous cryogenic stage. Several such “unconventional” acoustic tests continued throughout the GSLV qualification programme and over the last year, the indigenous cryo engine/stage subsystems underwent a number of these tests, the results of which were very closely linked to the actual integration of the flight stage. It is very heartening to note that the results / observations of the acoustic tests conducted on several subsystems of the cryo stage at ATF had a direct impact on the integration and assembly processes of the stage. In addition, changes incorporated in the assembly processes of the stage were also being verified for integrity under acoustic loading. For such acoustic tests, very high acoustic levels of the order of 164 dB were required to excite very localized areas on the specimen. The wire tunnel , umbilical connector units , the cryo stage vent valves , the LH2 vent and relief line and the protection plates in the ITT region were required to be subjected to such localized, high acoustic levels.In order to provide such high acoustic levels, ATF had to carry out extensive mapping of acoustic amplitude and frequency in the immediate vicinity of the exponential horns and provide specimen mounting interfaces at these locations . This work needed to be carried out in almost real time since the test requirements were continuously changing based on various considerations and recommendations of test and evaluation committees. The image below shows the wire tunnel of the cryo stage mounted at a height of 11.5 metres near the 25 Hz exponential horn to carry out an acoustic test at a level of 164 dB at low frequencies. A similar test was also conducted on the umbilical connector unit which houses the interfaces (both electrical as well as cryo fuel) between the launch pedestal and the cryogenic stage. The entire umbilical connector unit assembly was also acoustic tested near the 25 Hz horn at 11.5 metres height. The series of acoustic tests also involved assembly of the wire tunnel and the umbilical connector unit , as on the flight stage and testing the combination near the 80 / 160 Hz horns of ATF at levels of 162 dB. The test sequence involved , simulation of a variety of fastening techniques and also the use of teflon, metallic inserts and washers to determine torque retention in the fastened assemblies. The results of these tests played a major role in the finalization of fastening techniques for a large number of assemblies. Tests were also carried out on the carbon composite cover plates used in the inter tank truss region of the cryo stages to provide protection to the various gas line interfaces located there. An acoustic test was also carried out on the Liquid Hydrogen Vent Pipe and the vent valve assembly. This is also a very crucial subassembly of the cryogenic stage.
A major acoustic test programme involved tests on a subassembly of the cryogenic stage consisting of the liquid oxygen tank, the lower shroud covering the the truss region, truncated main cryogenic engine, the steering engine, the wire tunnel in the tank and shroud portion, the Inter Stage 2/3L and the separation plane connectors. The principal purpose of this test was to determine the integrity of the shroud, verify separation connector mating status and to determine the induced vibration response for the specified acoustic loading. This test was conducted at 156 dB. This test simulated , redesigned and upgraded hardware to overcome issues in the unsuccessful GSLV-F06 flight where the lower shroud failed and the separation plane connectors snapped leading to loss of connectivity and subsequent destruction of the vehicle from ground.
ATF has designed and fabricated unique test fixtures for all the GSLV test programmes. Since the test specimen are all unique, suitable fixtures and interfaces to mount the test specimen on the existing specimen trolley at ATF require to be designed, load tested and approved by a combined ATF-VSSC test and evaluation team , before being used for the actual tests.
The ATF team has also significantly contributed to the several Environmental Test Level Committees, Test and Evaluation Committees and other forum in ISRO which decide the acoustic test specifications as well as the test configuration , test sequence and inspection parameters.
Most of the acoustic test programmes mentioned were specifically for the GSLV-D5 mission. The extensive test programmes spread over the last year and a half catered to the redesign and qualification of major subsystems and assemblies of the indigenous cryogenic stage. The team at ATF is proud to be associated with ISRO’s GSLV programme and the years of dedication and hard work , sometimes stretching over months with very little personal time has ultimately paid off with the hugely successful flight of the GSLV-D5 and the excellent performance of the indigenous cryogenic engine.
K N Arun Kumar
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ANU ties up with ISRO for radar design
Acharya Nagarjuna University will now partner Satish Dhawan Space Centre (SDSC)-SHAR, Indian Space Research Organisation (ISRO) in designing a Multi Object Tracking Radar (MOTR) to be used in defence surveillance.
Vice-Chancellor K. Viyanna Rao said on Friday that ANU has entered into a Memorandum of Understanding with SDSC-SHAR to design the MOTR, becoming the first university in the country to have a tie-up with SDSC-SHAR in designing indigenous radars. India is the fourth nation in the world, after the US, Japan and Germany to design MOTRs, he said.
MoU signed
Associate Director of SHAR and Project Director, MOTR, V. Seshagiri Rao signed the MoU with Dean of ANU Engineering College and principal investigator of the project, P. Siddaiah.
“Conventional radars are designed to track one object but the MOTR is being designed to track multiple objects simultaneously from a distance of 1,000 km. It is also used in tracking the path of satellites in various stages,” said Dr. Siddaiah.
A first
The radar, the first-of-its-kind in the country, is being designed with 4,600 antennas at a cost of Rs.253 crore.
Dr. Siddaiah said the university would provide high frequency structural simulator software for designing the radar. The ISRO had allotted three research fellows and one technical officer, besides a grant of Rs.28 lakh to execute the project.
It is being designed to track multiple objects from a distance of 1,000 km .
ANU ties up with ISRO for radar design | idrw.org
I have friends who study in ANU, really good university.
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‘Botanists Should Help ISRO on Agri Sat’ -The New Indian Express
Botanists and biologists must join hands with the Indian Space Research Organisation (ISRO) to launch an ‘Agri Satellite’ for increasing yield on the lines of China’s ‘Space Seed Experiment,’ said former secretary and ex-member (Finance) of Atomic Energy Commission V V Bhat on Monday.
He was speaking at a workshop ‘A Day With Farmers’ organised by the Department of Studies in Botany of University of Mysore in the city.
He said China has increased its agricultural yield by 25 per cent through ‘Space Seed Experiment’. “Under the concept, seeds are sent to space in satellites in order to develop new crop breeds by identifying mutation through space radiation,” he said.
Though India has manpower, it requires integration and team work involving faculty and experts of varsities and institutions to make it possible, he felt.
“ISRO is ready to take up the project. Botanists and biologists should find out which crop the natural transmutation can be done easily, thus helping the scientific revolution,” he said.
Bhat said only such measures can increase food production in the country.
“There is a need to grow crops that are less resource intensive, cause less damage to the environment and increase nutrition. The sorry state of agriculture is due to lack of integrated vision and various crop research institutes are working in isolation,” he said.
Due to lack of sponsorship from government agencies, research is carried out by many institutes in a few areas that are sponsored by private firms.
“Hence, India has not been able to remain an agriculture-based country. Other fields are generating more jobs. We are creating a situation where people are weaned away from agriculture,” he said.
Stating that the National Sample Survey shows many people are ready to take up agriculture if they get an opportunity, he stressed the need to focus more on agriculture.
Prof S Shankar Bhat, founder of Plant Clinic, stressed the need to set up mobile plant clinics to reach out to the farmers.
Plant clinics will help find the exact cause of plant disease and suggest measures to prevent them.
UoM Vice-Chancellor K S Rangappa and Dr Vasanthkumar Thimakapura, director of Greenlife Science Technology Pvt Ltd, were present.
Botanists and biologists must join hands with the Indian Space Research Organisation (ISRO) to launch an ‘Agri Satellite’ for increasing yield on the lines of China’s ‘Space Seed Experiment,’ said former secretary and ex-member (Finance) of Atomic Energy Commission V V Bhat on Monday.
He was speaking at a workshop ‘A Day With Farmers’ organised by the Department of Studies in Botany of University of Mysore in the city.
He said China has increased its agricultural yield by 25 per cent through ‘Space Seed Experiment’. “Under the concept, seeds are sent to space in satellites in order to develop new crop breeds by identifying mutation through space radiation,” he said.
Though India has manpower, it requires integration and team work involving faculty and experts of varsities and institutions to make it possible, he felt.
“ISRO is ready to take up the project. Botanists and biologists should find out which crop the natural transmutation can be done easily, thus helping the scientific revolution,” he said.
Bhat said only such measures can increase food production in the country.
“There is a need to grow crops that are less resource intensive, cause less damage to the environment and increase nutrition. The sorry state of agriculture is due to lack of integrated vision and various crop research institutes are working in isolation,” he said.
Due to lack of sponsorship from government agencies, research is carried out by many institutes in a few areas that are sponsored by private firms.
“Hence, India has not been able to remain an agriculture-based country. Other fields are generating more jobs. We are creating a situation where people are weaned away from agriculture,” he said.
Stating that the National Sample Survey shows many people are ready to take up agriculture if they get an opportunity, he stressed the need to focus more on agriculture.
Prof S Shankar Bhat, founder of Plant Clinic, stressed the need to set up mobile plant clinics to reach out to the farmers.
Plant clinics will help find the exact cause of plant disease and suggest measures to prevent them.
UoM Vice-Chancellor K S Rangappa and Dr Vasanthkumar Thimakapura, director of Greenlife Science Technology Pvt Ltd, were present.
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We trust our cryogenic engine , capability to launch heavier satellites now been established’ : ISRO Chief
In this Walk the Talk on NDTV 24×7 with The Indian Express Editor-in-Chief Shekhar Gupta, ISRO Chairman K Radhakrishnan speaks about the indigenous cryogenic engine that launched GSLV-D5 and why the Mars Orbiter Mission is crucial for India.
I’m at Antariksh Bhavan in Bangalore, the headquarters of the Indian Space Research Organisation (ISRO), where you see many smiles wherever you go and nobody is smiling more happily than its Chairman Dr K Radhakrishnan. One can’t find a space scientist with a more diverse portfolio — the Mars mission, the lunar mission, GSLV and then your own Tsunami Warning Centre, and the 24×7 Disaster Management Centre. You are a man of many parts.
The Indian space programme is people-centric and application-centric. That’s our USP, that whatever we do, it should finally find a place for the common man.
And you have had about eight launches in seven months?
Yes, since July 2013, we have had eight successful missions — PSLVs, a few satellites, the Mars Orbiter Mission and the latest GSLV-D5 with the Indian cryogenic engine and stage.
Teach us some rocket science… explain to people who can’t tell the difference between geostationary and polar.
Essentially, when we talk about a satellite doing remote-sensing, it has to go above the Earth from pole to pole. As the Earth rotates, and the satellite goes from pole to pole, the cameras in the satellite would be able to see the entire Earth. It can take pictures, as and when you require or periodically. In the case of communication satellites, what we do is put a satellite at an altitude of 36,000 km above the equator. The satellite would take 24 hours for one revolution, which is equal to what it takes for the Earth too (to rotate on its axis). So the satellite would be geostationary, that is, a stationary object with respect to us on the Earth. So these are the two things we generally talk about. The Polar Satellite Launch Vehicle can launch remote-sensing satellites, satellites for space science experiments, satellites for communication, it has also launched Chandrayaan and the Mars Orbiter. So in the PSLV family, we have three vehicles. Now, GSLV is a more powerful vehicle. The core stage of PSLV is used in GSLV too. The second stage of PSLV is adapted and used in GSLV.
More or less replicated?
Yes, and here you will see large strap-ons, liquid engine-based strap-ons.
And I believe each one of them carries 200 tonnes of fuel?
Each of them carries 40 tonnes and the core has 139 tonnes of solid propellant. But the most important and crucial element of GSLV is the cryogenic upper stage and that’s what we tested successfully.
Sir, now that I am getting my tutorial on rocket science, tell us the meaning of cryogenic. I know ‘cryo’ is something that is cold.
There are three varieties of propulsion used for rockets. One is the solid propellant base. That means you have got the solid fuel and the solid oxidiser, plus a few additives. This can be used in the lower stages of the vehicle. It’s easy to handle once you prepare it. But when you talk about the liquid engine, there is an oxidiser and fuel. The fuel can be kerosene or liquid hydrogen. When it is liquid hydrogen, we call it cryogenic.
And now you go on to your next GSLV.
If you look at GSLV Mark III, which we are now developing, it is far more powerful compared to GSLV. In GSLV, we can put a 2,200 kg satellite into a geostationary transfer orbit — that means in an orbit where the apogee is 36,000 km and perigee is 200 km — whereas in GSLV Mark III, we can take to the orbit a satellite of 4,000 kg. So that’s almost double the capacity.
Sir, if you can explain perigee and apogee…
Perigee means the distance closest to the Earth and apogee is the farthest point.
So, as it goes into elliptical orbit around the Earth, sometimes it will be closer, sometimes it will be farther?
Exactly. So using the propulsion system in the satellite, we move it into a 36,000 km circular orbit and take it to a place above the equator.
So when are you planning this launch, the next landmark?
The first landmark is an experimental mission where we will look at the atmospheric phase of this flight and we will use a passive ignition stage, in the sense that it won’t ignite. But all the lower stages will perform and we will monitor the performance of this vehicle in the crucial atmospheric phase. This is going to happen by April 2014.
By testing out its response to atmospheric conditions, you mean that in the first 30-40 km, it will face winds and pressures which don’t exist in outer space?
Right.
So when do you expect the full launch of this?
The full launch should be possible by 2016-17. What we have done now is testing of the engine. Some of the stage components have also been tested. So for the next two years, we will go through a qualification programme for the engine as well as the stage. Once it is completed, then we will be able to release this vehicle.
Then we can launch much bigger satellites for which we today have to go overseas?
We will be able to launch communication satellites weighing about 3,500 kg to 4,000 kg. Today we do it through Ariane-5 rockets.
So, what happened in the past? Why has GSLV given us such trouble?
There are two reasons. GSLV, of course, is a beautiful vehicle and a simpler vehicle, except for the complex cryogenic stage. GSLV derives its heritage from the sub-systems of PSLV, in terms of the solid core stage and the liquid strap-ons and the second stage. It uses liquid propulsion where we need to get a lot of controlled components. During the flight or during the preparation phase, it can leak a little bit. The second part is incidental — in the first GSLV flight that was done in 2001, one of the strap-ons did not ignite, it did not get the fuel. But there was an inbuilt system for aborting the flight… that worked beautifully and the flight was aborted. Within 22 days — it was a record — our people brought it back to the launch pad.
And the whole thing was saved?
Yes. But the satellite did not stay there for more than two months because the Russian cryogenic stage at that time did not perform to its required level. It was underperformance of that stage but nevertheless it is a first developmental flight of GSLV and a very crucial milestone for the country. The second and third flights of GSLV worked very well. It launched GSAT2 and GSAT3, what you call Edusat. In the GSLV flight that we did in 2006, one of the components in a strap-on did not perform properly. That means the vehicle had to go with only three strap-ons. It was a failure. The next flight that we undertook in 2007, the control system of one of the strap-ons failed. However, the vehicle was able to put the satellite into an orbit very close to where we wanted it. And then the satellite propulsion system was used to take the satellite, INSAT-4CR, into the right place. So nothing was basically wrong with GSLV but component failure resulted in these few failures. In 2010, we had two flights. The first one was to test our Indian cryogenic engine and stage. Here too the vehicle beautifully performed up to the end of the second stage. The cryo stage ignited and we were very happy at that time. But immediately after that, a fuel booster turbo pump stopped.
Why did that happen?
We investigated and found there are three possibilities. One, of course, is contamination. It is sitting in a liquid hydrogen tank. It is at very low temperature and…
How low?
It is 20 Kelvin or -253°C. There are dissimilar materials used in the pump and the contractions will not be uniform. We also had a possibility of a casing of the pump coming out, so these two had to be corrected. But later we found out that the most probable cause was contamination from a propellant acquisition system kept in the liquid hydrogen tank. So we replaced that, redesigned it and got a new one. We also tested this pump extensively in this low temperature condition and ensured that it works. The second part of it was, had this pump worked, are we sure that the rest of the functions would take place? We did a lot of analysis and simulation. And one thing we wanted to make sure before we took off again was to see that this cryogenic engine ignites and we are sure about it at this high altitude condition where there is vacuum. We had not tested this in the past on the ground. So we created a test facility at Mahendragiri (Tamil Nadu) and then we tested it and saw to it that we are confident about it.
So that’s why this launch with an Indian cryogenic engine is such a landmark?
It’s three years of work, during which we did 45 tests on the ground on the cryogenic engine and stage. Also, why did the GSLV configuration fail? Is there something fundamentally wrong it? We did nearly 850 wind tunnel tests.
But now you don’t have that doubt?
Now, we don’t have that doubt.
So we can take the view that your successful GSLV with your own cryogenic engine is an even bigger landmark than the Mars Mission, which was ahead of the lunar mission.
Both are landmarks. One, in terms of technology, cryogenic technology is complex and we have done it.
It greatly increases your range and payload.
Yes, and the capability of India to launch heavier satellites has now been established. The Mars Orbiter Mission is critical for space exploration. It also shows India’s capability to take a spacecraft to a distance of 400 million km, control it properly there and then conduct experiments
But sir, there is also scepticism. After so many rovers, so many landers, what will this bring back?
The objective of this mission is to prove our technological capability to precisely orbit a satellite around Mars. There have been 51 Mars missions; only 21 were successful. Secondly, the scientific objective is to study the presence of methane. Why is methane important? We want to understand the existence of life on Mars.
Could we find something that has not already been explored, given so many missions that have been successful?
The presence of methane or otherwise, and the origin of that, whether it is geological or biological, that is something that this mission is going to look at. Also, the atmospheric processes on Mars…
Well, the remarkable thing is the cost of the mission.
Cost and time, both. We have done it at 1/10th the cost.
There is one more reason why this cryogenic is important. Because I was a sort of a participant in the tamasha that went on more than two decades earlier, of how this programme got a setback (the spy scandal). I used to then work for India Today and I had done a story saying these allegations of spying were wrong. Have you reflected very much on that? Was it a setback to ISRO?
The programme goes on. We have come out of all those and today we have the technology with us.
What is it that makes ISRO different? Somehow, ISRO manages to do more tangible work than most other government organisations.
When we conceive a programme, we look at how it is going to be useful for people, how to reach it to people and how to build systems so that it becomes part of the value chain of those people.
But you also have a better industry interface.
Yes, we had decided from the seventies that Indian industries, both public and private, are going to be part of us. We also make the best use of the academic community in doing research activities.
You got your MBA from IIM-Bangalore before you got your PhD from IIT-Kharagpur.
That’s true.
So you are a businessman as well as a scientist. What made you go for an MBA before you went to research?
Because of the uncertainty involved in high-technology programmes like space, they had to use several of these management techniques.
But your commercial arm Antrix has been struggling a little bit?
If you look at the turnover of Antrix, it has been going up. We recently launched a SPOT 6 satellite, one of the best remote sensing satellites in the world, and SPOT 7 is ready to be launched.
I know remote-sensing is your own special field of interest.
That’s true. Antrix has been contributing a lot to the communication satellite programme. A number of satellites of foreign countries are lined up for launch using our PSLV. The recently launched microwave remote sensing satellite… is also going to be used by foreign customers through an arrangement with Antrix.
But Antrix also got an undue share of controversy for getting into an arrangement with a private company. Two things appeared, one the word ‘spectrum’; second, the word ‘private company’. And somebody even put a figure of Rs 2 lakh crore, because we can’t settle for less than that for a scandal now.
Yes, much has been talked and written about this subject. Over the last three-and-a-half years, we have done what is best for the country, what is best for the government of India, what is best for research.
Was the controversy avoidable? Because there was no scandal.
I don’t want to get into the merit of it because it is going through a legal process at the moment. But what has been done is best for the country.
You have done the damage control?
Yes.
Kiran Karnik was on this show and he said that having seen so much of the government of India, so much of India, he has never found another Indian organisation with a commitment and integrity to match ISRO’s, which is a high compliment.
Thank you. We have done what we thought and what we think is best for the country.
And you have a track record to deserve the highest of compliments. Dr Radhakrishnan, thank you very much. I know you have many more frontiers to climb and they wait— one in April and one in a couple of years from now. And towards the end of this year, you put your Mars Orbiter in space.
September 24, 2014 is a crucial day for the Mars Orbiter, when we have to precisely reduce the velocity of the spacecraft and make it orbit. If we miss that, then we lose the mission. But we are hopeful.
I am sure you will take no chances. Because one thing that intrigues me all the time is how religious many of your scientists are — you find coconuts being broken, pujas, mantras…
We are all Indians…
So, science or no science… you see no contradiction?
We don’t see any contradiction.
We trust our cryogenic engine , capability to launch heavier satellites now been established’ : ISRO Chief | idrw.org
‘India made Aryabhatta have more weight at then Soviet Union’s insistence’
The weight of the first Indian satellite Aryabhatta could have been lighter than the Chinese satellite launched beforehand had the then Soviet Union didn’t convince India of making it more than the Chinese one, says K Kasturirangan, former director of the Indian Space Research Organization (ISRO 1994 to 2003) while sharing insights about the space organization during his talk on theme ‘Aryabhatta to Mangalyan – India’s tryst with Science and Technology’ in Jaipur on Saturday.
“The Soviet Union wanted our satellite size bigger than those of Chinese despite the fact we had designed a much lighter one. Finally, we end up making a 360 kg satellite making it much more weightier than that of Chinese which is 160 kg,” the former director said without revealing much of the details at a private university here.
Kasturirangan was conferred the JK Lakshmipat University Laureate Award 2013 in recognition of his phenomenal contribution to the field of science and innovation. The award was given away by chancellor of the university Bharat Hari Singhania. The talk he delivered was on the occasion of the first Hari Shakar memorial oration series.
He also revealed how satellite Chandrayan-1, India’s first unmanned lunar probe to the moon, was named and conceptualized. “ISRO gave a presentation to then prime minister Atal Bihari Vajpaee who readily accepted the proposal. At that time, the project was named Somyana which Vajpayee changed to Chandrayan while announcing it on August 15, 2003,” said Kasturirangan, also a Padma Bhushan awardee. Later, when ISRO learnt that the name was changed by the prime minister as he find Chadrayan more expressive, it added ’1′ to make a series of satellites to the moon instead of only one.
He said India is among leaders when it comes to space exploration. Talking about the accuracy of the Indian satellites, Kasturiangan said, “Satellite images of Cyclone Phailin helped the administration to avert huge damage.” The scientist also said India is at a par with the US and France in 1980s in terms of advanced cameras while images from the space and height to which they send satellites.
He attributed India’s space program to Vikram Sarabhai who has first undertook the initiative and explained to leaders of the country that space explorations can be helpful to humanity in education, disaster management, health and agriculture, which all came true today. Kasturiangan encouraged students saying explorations in space are the just tip of an iceberg and students with zeal can have a bright career in the field.
‘India made Aryabhatta have more weight at then Soviet Union’s insistence’ | idrw.org
In this Walk the Talk on NDTV 24×7 with The Indian Express Editor-in-Chief Shekhar Gupta, ISRO Chairman K Radhakrishnan speaks about the indigenous cryogenic engine that launched GSLV-D5 and why the Mars Orbiter Mission is crucial for India.
I’m at Antariksh Bhavan in Bangalore, the headquarters of the Indian Space Research Organisation (ISRO), where you see many smiles wherever you go and nobody is smiling more happily than its Chairman Dr K Radhakrishnan. One can’t find a space scientist with a more diverse portfolio — the Mars mission, the lunar mission, GSLV and then your own Tsunami Warning Centre, and the 24×7 Disaster Management Centre. You are a man of many parts.
The Indian space programme is people-centric and application-centric. That’s our USP, that whatever we do, it should finally find a place for the common man.
And you have had about eight launches in seven months?
Yes, since July 2013, we have had eight successful missions — PSLVs, a few satellites, the Mars Orbiter Mission and the latest GSLV-D5 with the Indian cryogenic engine and stage.
Teach us some rocket science… explain to people who can’t tell the difference between geostationary and polar.
Essentially, when we talk about a satellite doing remote-sensing, it has to go above the Earth from pole to pole. As the Earth rotates, and the satellite goes from pole to pole, the cameras in the satellite would be able to see the entire Earth. It can take pictures, as and when you require or periodically. In the case of communication satellites, what we do is put a satellite at an altitude of 36,000 km above the equator. The satellite would take 24 hours for one revolution, which is equal to what it takes for the Earth too (to rotate on its axis). So the satellite would be geostationary, that is, a stationary object with respect to us on the Earth. So these are the two things we generally talk about. The Polar Satellite Launch Vehicle can launch remote-sensing satellites, satellites for space science experiments, satellites for communication, it has also launched Chandrayaan and the Mars Orbiter. So in the PSLV family, we have three vehicles. Now, GSLV is a more powerful vehicle. The core stage of PSLV is used in GSLV too. The second stage of PSLV is adapted and used in GSLV.
More or less replicated?
Yes, and here you will see large strap-ons, liquid engine-based strap-ons.
And I believe each one of them carries 200 tonnes of fuel?
Each of them carries 40 tonnes and the core has 139 tonnes of solid propellant. But the most important and crucial element of GSLV is the cryogenic upper stage and that’s what we tested successfully.
Sir, now that I am getting my tutorial on rocket science, tell us the meaning of cryogenic. I know ‘cryo’ is something that is cold.
There are three varieties of propulsion used for rockets. One is the solid propellant base. That means you have got the solid fuel and the solid oxidiser, plus a few additives. This can be used in the lower stages of the vehicle. It’s easy to handle once you prepare it. But when you talk about the liquid engine, there is an oxidiser and fuel. The fuel can be kerosene or liquid hydrogen. When it is liquid hydrogen, we call it cryogenic.
And now you go on to your next GSLV.
If you look at GSLV Mark III, which we are now developing, it is far more powerful compared to GSLV. In GSLV, we can put a 2,200 kg satellite into a geostationary transfer orbit — that means in an orbit where the apogee is 36,000 km and perigee is 200 km — whereas in GSLV Mark III, we can take to the orbit a satellite of 4,000 kg. So that’s almost double the capacity.
Sir, if you can explain perigee and apogee…
Perigee means the distance closest to the Earth and apogee is the farthest point.
So, as it goes into elliptical orbit around the Earth, sometimes it will be closer, sometimes it will be farther?
Exactly. So using the propulsion system in the satellite, we move it into a 36,000 km circular orbit and take it to a place above the equator.
So when are you planning this launch, the next landmark?
The first landmark is an experimental mission where we will look at the atmospheric phase of this flight and we will use a passive ignition stage, in the sense that it won’t ignite. But all the lower stages will perform and we will monitor the performance of this vehicle in the crucial atmospheric phase. This is going to happen by April 2014.
By testing out its response to atmospheric conditions, you mean that in the first 30-40 km, it will face winds and pressures which don’t exist in outer space?
Right.
So when do you expect the full launch of this?
The full launch should be possible by 2016-17. What we have done now is testing of the engine. Some of the stage components have also been tested. So for the next two years, we will go through a qualification programme for the engine as well as the stage. Once it is completed, then we will be able to release this vehicle.
Then we can launch much bigger satellites for which we today have to go overseas?
We will be able to launch communication satellites weighing about 3,500 kg to 4,000 kg. Today we do it through Ariane-5 rockets.
So, what happened in the past? Why has GSLV given us such trouble?
There are two reasons. GSLV, of course, is a beautiful vehicle and a simpler vehicle, except for the complex cryogenic stage. GSLV derives its heritage from the sub-systems of PSLV, in terms of the solid core stage and the liquid strap-ons and the second stage. It uses liquid propulsion where we need to get a lot of controlled components. During the flight or during the preparation phase, it can leak a little bit. The second part is incidental — in the first GSLV flight that was done in 2001, one of the strap-ons did not ignite, it did not get the fuel. But there was an inbuilt system for aborting the flight… that worked beautifully and the flight was aborted. Within 22 days — it was a record — our people brought it back to the launch pad.
And the whole thing was saved?
Yes. But the satellite did not stay there for more than two months because the Russian cryogenic stage at that time did not perform to its required level. It was underperformance of that stage but nevertheless it is a first developmental flight of GSLV and a very crucial milestone for the country. The second and third flights of GSLV worked very well. It launched GSAT2 and GSAT3, what you call Edusat. In the GSLV flight that we did in 2006, one of the components in a strap-on did not perform properly. That means the vehicle had to go with only three strap-ons. It was a failure. The next flight that we undertook in 2007, the control system of one of the strap-ons failed. However, the vehicle was able to put the satellite into an orbit very close to where we wanted it. And then the satellite propulsion system was used to take the satellite, INSAT-4CR, into the right place. So nothing was basically wrong with GSLV but component failure resulted in these few failures. In 2010, we had two flights. The first one was to test our Indian cryogenic engine and stage. Here too the vehicle beautifully performed up to the end of the second stage. The cryo stage ignited and we were very happy at that time. But immediately after that, a fuel booster turbo pump stopped.
Why did that happen?
We investigated and found there are three possibilities. One, of course, is contamination. It is sitting in a liquid hydrogen tank. It is at very low temperature and…
How low?
It is 20 Kelvin or -253°C. There are dissimilar materials used in the pump and the contractions will not be uniform. We also had a possibility of a casing of the pump coming out, so these two had to be corrected. But later we found out that the most probable cause was contamination from a propellant acquisition system kept in the liquid hydrogen tank. So we replaced that, redesigned it and got a new one. We also tested this pump extensively in this low temperature condition and ensured that it works. The second part of it was, had this pump worked, are we sure that the rest of the functions would take place? We did a lot of analysis and simulation. And one thing we wanted to make sure before we took off again was to see that this cryogenic engine ignites and we are sure about it at this high altitude condition where there is vacuum. We had not tested this in the past on the ground. So we created a test facility at Mahendragiri (Tamil Nadu) and then we tested it and saw to it that we are confident about it.
So that’s why this launch with an Indian cryogenic engine is such a landmark?
It’s three years of work, during which we did 45 tests on the ground on the cryogenic engine and stage. Also, why did the GSLV configuration fail? Is there something fundamentally wrong it? We did nearly 850 wind tunnel tests.
But now you don’t have that doubt?
Now, we don’t have that doubt.
So we can take the view that your successful GSLV with your own cryogenic engine is an even bigger landmark than the Mars Mission, which was ahead of the lunar mission.
Both are landmarks. One, in terms of technology, cryogenic technology is complex and we have done it.
It greatly increases your range and payload.
Yes, and the capability of India to launch heavier satellites has now been established. The Mars Orbiter Mission is critical for space exploration. It also shows India’s capability to take a spacecraft to a distance of 400 million km, control it properly there and then conduct experiments
But sir, there is also scepticism. After so many rovers, so many landers, what will this bring back?
The objective of this mission is to prove our technological capability to precisely orbit a satellite around Mars. There have been 51 Mars missions; only 21 were successful. Secondly, the scientific objective is to study the presence of methane. Why is methane important? We want to understand the existence of life on Mars.
Could we find something that has not already been explored, given so many missions that have been successful?
The presence of methane or otherwise, and the origin of that, whether it is geological or biological, that is something that this mission is going to look at. Also, the atmospheric processes on Mars…
Well, the remarkable thing is the cost of the mission.
Cost and time, both. We have done it at 1/10th the cost.
There is one more reason why this cryogenic is important. Because I was a sort of a participant in the tamasha that went on more than two decades earlier, of how this programme got a setback (the spy scandal). I used to then work for India Today and I had done a story saying these allegations of spying were wrong. Have you reflected very much on that? Was it a setback to ISRO?
The programme goes on. We have come out of all those and today we have the technology with us.
What is it that makes ISRO different? Somehow, ISRO manages to do more tangible work than most other government organisations.
When we conceive a programme, we look at how it is going to be useful for people, how to reach it to people and how to build systems so that it becomes part of the value chain of those people.
But you also have a better industry interface.
Yes, we had decided from the seventies that Indian industries, both public and private, are going to be part of us. We also make the best use of the academic community in doing research activities.
You got your MBA from IIM-Bangalore before you got your PhD from IIT-Kharagpur.
That’s true.
So you are a businessman as well as a scientist. What made you go for an MBA before you went to research?
Because of the uncertainty involved in high-technology programmes like space, they had to use several of these management techniques.
But your commercial arm Antrix has been struggling a little bit?
If you look at the turnover of Antrix, it has been going up. We recently launched a SPOT 6 satellite, one of the best remote sensing satellites in the world, and SPOT 7 is ready to be launched.
I know remote-sensing is your own special field of interest.
That’s true. Antrix has been contributing a lot to the communication satellite programme. A number of satellites of foreign countries are lined up for launch using our PSLV. The recently launched microwave remote sensing satellite… is also going to be used by foreign customers through an arrangement with Antrix.
But Antrix also got an undue share of controversy for getting into an arrangement with a private company. Two things appeared, one the word ‘spectrum’; second, the word ‘private company’. And somebody even put a figure of Rs 2 lakh crore, because we can’t settle for less than that for a scandal now.
Yes, much has been talked and written about this subject. Over the last three-and-a-half years, we have done what is best for the country, what is best for the government of India, what is best for research.
Was the controversy avoidable? Because there was no scandal.
I don’t want to get into the merit of it because it is going through a legal process at the moment. But what has been done is best for the country.
You have done the damage control?
Yes.
Kiran Karnik was on this show and he said that having seen so much of the government of India, so much of India, he has never found another Indian organisation with a commitment and integrity to match ISRO’s, which is a high compliment.
Thank you. We have done what we thought and what we think is best for the country.
And you have a track record to deserve the highest of compliments. Dr Radhakrishnan, thank you very much. I know you have many more frontiers to climb and they wait— one in April and one in a couple of years from now. And towards the end of this year, you put your Mars Orbiter in space.
September 24, 2014 is a crucial day for the Mars Orbiter, when we have to precisely reduce the velocity of the spacecraft and make it orbit. If we miss that, then we lose the mission. But we are hopeful.
I am sure you will take no chances. Because one thing that intrigues me all the time is how religious many of your scientists are — you find coconuts being broken, pujas, mantras…
We are all Indians…
So, science or no science… you see no contradiction?
We don’t see any contradiction.
We trust our cryogenic engine , capability to launch heavier satellites now been established’ : ISRO Chief | idrw.org
‘India made Aryabhatta have more weight at then Soviet Union’s insistence’
The weight of the first Indian satellite Aryabhatta could have been lighter than the Chinese satellite launched beforehand had the then Soviet Union didn’t convince India of making it more than the Chinese one, says K Kasturirangan, former director of the Indian Space Research Organization (ISRO 1994 to 2003) while sharing insights about the space organization during his talk on theme ‘Aryabhatta to Mangalyan – India’s tryst with Science and Technology’ in Jaipur on Saturday.
“The Soviet Union wanted our satellite size bigger than those of Chinese despite the fact we had designed a much lighter one. Finally, we end up making a 360 kg satellite making it much more weightier than that of Chinese which is 160 kg,” the former director said without revealing much of the details at a private university here.
Kasturirangan was conferred the JK Lakshmipat University Laureate Award 2013 in recognition of his phenomenal contribution to the field of science and innovation. The award was given away by chancellor of the university Bharat Hari Singhania. The talk he delivered was on the occasion of the first Hari Shakar memorial oration series.
He also revealed how satellite Chandrayan-1, India’s first unmanned lunar probe to the moon, was named and conceptualized. “ISRO gave a presentation to then prime minister Atal Bihari Vajpaee who readily accepted the proposal. At that time, the project was named Somyana which Vajpayee changed to Chandrayan while announcing it on August 15, 2003,” said Kasturirangan, also a Padma Bhushan awardee. Later, when ISRO learnt that the name was changed by the prime minister as he find Chadrayan more expressive, it added ’1′ to make a series of satellites to the moon instead of only one.
He said India is among leaders when it comes to space exploration. Talking about the accuracy of the Indian satellites, Kasturiangan said, “Satellite images of Cyclone Phailin helped the administration to avert huge damage.” The scientist also said India is at a par with the US and France in 1980s in terms of advanced cameras while images from the space and height to which they send satellites.
He attributed India’s space program to Vikram Sarabhai who has first undertook the initiative and explained to leaders of the country that space explorations can be helpful to humanity in education, disaster management, health and agriculture, which all came true today. Kasturiangan encouraged students saying explorations in space are the just tip of an iceberg and students with zeal can have a bright career in the field.
‘India made Aryabhatta have more weight at then Soviet Union’s insistence’ | idrw.org
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How Isro got an indigenous cryogenic engine
Mission director K. Sivan kept his fingers firmly crossed in the mission control room at the Indian Space Research Organisation (Isro) Satish Dhawan Space Centre in Sriharikota on the morning of 5 January as the moment drew closer for the launch of the Geosynchronous Satellite Launch Vehicle, or GSLV-D5.
The rocket, powered by India’s indigenous cryogenic engine, had been tested and reviewed numerous times in the four months since its aborted launch on 19 August due to a crack in the fuel tank. After the 5 January launch, every step that the rocket cleared made Sivan a happier man. But he also became more anxious—after all, of the seven GSLV launches earlier, five had failed. It was only when the satellite GSAT-14 onboard the GSLV-D5 was inserted into a precise orbit that Sivan relaxed. “It was like the rebirth of GSLV,” he said.
The search for cryogenic engine
The GSLV programme was started by Isro in response to India’s mounting communications needs. By 1987, the government had approved the development of the second generation INSAT-2 series of satellites, weighing more than 2 tonnes. Isro wanted to develop a 2.5-tonne class of satellites and put them into a geostationary transfer orbit at 36,000km from Earth’s surface.
Isro also wanted to make a vehicle that would be bigger, lighter and more efficient than its workhorse Polar Satellite Launch Vehicle (PSLV). There were three fuels options: earth storable, semi-cryogenic, and cryogenic.
Cryogenic engines, which use liquid hydrogen and liquid oxygen as fuel and give the most thrust, are usually prepared for the “upper stages”—the last stage of the rocket—because this stage provides 50% of the velocity of 10.2km per second needed at the point of injection of a satellite. In 1986, at a cost of Rs.12 crore, Isro scientists began developing a one-tonne cryogenic engine to try and understand how to handle liquid hydrogen and liquid oxygen. At the same time, a design team was formed at Isro’s Liquid Propulsion Centre at Mahendragiri in Tamil Nadu to come up with the design of a seven-tonne turbo-fed engine. Although this development boosted the confidence of Isro engineers, Isro knew that it couldn’t wait much longer to develop the indigenous engine.
The Russian deal
It was then that Isro thought of procuring cryogenic engines from other countries. After rejecting offers from the US and France for both the sale of engines and transfer of technology, India approved an offer by the Soviet Union’s Glavkosmos space agency in 1990. India sent eight scientists to Moscow to work with Soviet scientists. They worked there for 15 months, but did not have access to everything.
“The Russians were very secretive about everything, even though they had signed the technology transfer agreement. Discussions were limited, and the Indian scientists were never allowed to walk the labs freely; they needed clearance to move around the lab,” said B.N. Suresh, former director, Vikram Sarabhai Space Centre in Thiruvananthapuram. “Hence they couldn’t learn very much.”
Then, 15 months after the deal was signed, the US raised objections citing a violation of the international Missile Technology Control Regime (MTCR). The West feared that cryogenic technology could be used by India to develop intercontinental ballistic missiles, which is rejected by Indian scientists. [Dont we all know why US wanted to deny cryo tech to us?]
Eventually, in 1993, Glavkosmos backed out of the deal and revoked the transfer of cryotechnology agreement. Under a renegotiated deal, Russia decided to provide four fully functional engines and two mock-ups. It also agreed to supply three more cryogenic engines at a cost of $9 million.
At this point, the Space Commission, which formulates and implements the Indian space programme, approved a Rs.280 crore project to develop an Indian cryogenic engine, the C12.
“We had to get back our people who were already working with the Russian scientists. Then we had to start on our own. They had made some sorts of drawings and designs and they were already working on the engines and fabrication processes with the Russian scientists,” said U.R. Rao, former chairman at Isro. “But still, many things cannot be on paper since there are various processes we go through to make every step as accurate as possible.”
Practical steps
Preparations were made for the first developmental flight of the GSLV-D1 with a procured Russian cryogenic third stage, planned for early 2001. A cryogenic upper stage (CUS) project had also speeded up the design and development of an indigenous engine to replace the Russian one.
“A lot of theoretical studies were conducted under E.V.S. Namboodiry, a propulsion expert who was in charge of studying the cryogenic engine with a team of experts. Something like 18 reports came out regarding cryogenic engine. But theories cannot give you a stage,” said Suresh.
Isro scientists had to become adept in areas such as materials technology, powder metallurgy, welding technology and fabrication technology.
2009-14: Road to success
Even as scientists gained experience from GSLV launches with a Russian cryogenic upper stage engine, they worked feverishly on the indigenous version. In 2009, Isro concentrated on developing infrastructure like the propellant casting facility for solid boosters. That year, Isro reached a landmark when the indigenous cryogenic engine was tested at the Mahendragiri and cleared for a full flight.
But the launch of the flight—the first with an indigenous engine—the GSLV-D3 in April 2010, with a GSAT-4 satellite on board, failed.
The rocket deviated from its path and the vehicle was seen “tumbling” down by Isro scientists. “The thing with rocket launches is that there is not much difference between success and failure. We succeeded (in 2014), but a tiny glitch and we could have ended up in the Bay of Bengal,” said R.V. Perumal, former director of the GSLV project.
The failure, a major disappointment to the nation, was caused by the fact that the cryogenic upper stage could not sustain ignition because the fuel booster turbo pump stopped working 293 seconds into the flight. The second developmental launch of the GSLV D-3 in December 2010 ended in an explosion due to a technical snag in the first stage.
“After the first failure (in 2010), the problem was that we could not recreate the cause of the failure, so it was hard to correct the problem,” said Sivan. “So we listed out possible failures, all feasible reasons for the stopping of fuel booster pump, and took corrective actions for all of them.”
“Even though we would test the engine and the ignition sequence on the ground, the conditions on the flight would be much different,” said Sivan. For Isro, it now became necessary to create those conditions for testing. A high altitude test facility was built in Mahendragiri in 2012 to demonstrate successful ignition for simulated flight conditions. And after testing the system in those conditions, Isro modified the ignition sequence.
Still, in August 2013, a GSLV-D5 launch was aborted at the eleventh hour after a leak was detected in the fuel booster pump. After decades of dogged engineering pursuit, this was an easier problem to solve for Isro.
“When we went ahead with the flight after testing the engine in every possible condition, we were confident of success. We had arrived,” said Sivan.
How Isro got an indigenous cryogenic engine | idrw.org
Thanks for Info.
Isro to launch IRNSS 1-B on April 4 | idrw.org
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