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ЦитироватьTango in space: Choose your partner carefullyApril 1, 2013 Rakesh Krishnan Simha A number of countries are looking for partners in space. Here's why India and Russia have the synergies that others lack.Nobody wants to be lonely in the final frontier. In an era where funding is as scarce as water on the moon, the once leading space-faring nations are scrambling for partners. India is one of the players being courted by the big three – NASA, Russia's Roscosmos and the European Space Agency (ESA).СпойлерWhile the big three have plenty of experience and grand plans for the future, they lack something that India has – a bottomless pool of scientific talent. And that's a big deal in the space industry today.The aerospace industry operates on such a vast scale that it requires prodigious numbers of scientific and technical personal to complete various – and often overlapping – projects. India's highly subsidised university system and the importance given to science and mathematics by Indian families ensure a steady supply of technical graduates in numbers that the West can only dream about.In the West, the recession is driving youngsters away fr om science degrees simply because there are not enough skilled jobs at the end of the course. The decline in the youth population in Europe and Russia will also impact scientific institutions in the decades ahead. While the United States has long depended on immigration to fill the talent gap, the rise in wealth and opportunities in India and China, NASA's two biggest sources, means America cannot bank on foreign talent in the future.Partnering with India, therefore, seems like the perfect get-out-of-jail card. Unlike China, India does not indulge in espionage at scientific establishments in the West. Its personnel are scientists – not spies.Now there's nothing wrong in alliances and teamwork, but there's one thing ISRO must not do – choose the wrong partner. Space is an area of strategic importance, and as they say in the military, a mistake in strategy cannot be undone in the same war.Russia: Trust mattersThe single biggest reason to go with Russia is that India can be the inheritor to Russia's legacy in space. Russia's space industry is vast but its population base is too small to support it. The average Russian space scientist is in his 50s – not a positive trend for the future.For Russia, ISRO can be a lifeline as many of the projects it can't handle can be farmed out to India. Also, Indian scientists can be sent to work in Russia's cutting-edge research labs that are off-limits to non-Russians.Trust is a key factor here. The Russians wouldn't trust NASA or the ESA anywhere around their research facilities. There is a lot of red hot technology locked away in deep vaults in once secret Russian cities. ISRO alone can be trusted to inspect and develop these technologies. This is because India is unlikely to become Russia's geopolitical or economic rival so any technology that is exchanged between the two nations is in safe hands.Wanted: Heavy liftersAccording to Space Daily, it is the failure to develop a fully reliable rocket to place heavy satellites in geostationary orbit that is restricting the rapid growth of India's space prowess. "One of the major reasons for the delay in India's second moon mission (Chandrayaan-II) is the absence of a reliable GSLV (Geo-Stationary Launch Vehicle)," says Space Daily. "Further, the absence of a GSLV is also affecting India's strategic preparedness because India cannot launch satellites required for strategic purposes fr om a foreign launch pad or atop a foreign rocket."That sounds pretty close to the truth. How's this for comparison – India's most reliable rocket, the PSLV, which launched its first lunar mission, can lift 2000 kg, wh ereas Europe's Ariane 5 is able to launch 10,000 kg into space.Because of the sheer weight of history and the bad blood between South Block and the Pentagon, NASA cannot help India in this area. The United States is paranoid about its key technologies being passed on to Russia, even if Russia clearly has no need for it. (The latest American rockets in development are based on technology purchased by NASA from Russia.)NASA knows India has beaten every technology embargo by reinventing the wheel. Every little nut and bolt that was available to its NATO allies but was banned for India, is being manufactured by ISRO and its contractors at home. NASA, therefore, knows India will sooner than later perfect its heavy lift rockets.So why does NASA want to partner with ISRO? One, India could play the very public – and very low tech – role as a launcher of American satellites and spacecraft. In return, NASA might offer a few dollies to India like low tech instruments, like the Moon Mineralogy Mapper, of no strategic value and which Indian laboratories can develop anyway.Another reason could be to keep India away from Roscosmos.India and Russia – Synergies that matterIndia's biggest strengths are in high-tech instrumentation and satellites. India not only has the largest constellation of remote sensing satellites orbiting the earth, it also has plans to create a satellite navigation system that will rival the American GPS.As well as super heavy-lift rockets like Energiya, the Russians were the first to develop landers and rovers that traversed the lunar surface before the Americans got anywhere close to the moon. Lately, Russia's soaring ambitions – epitomised by the Phobos Grunt mission to Mars – have come to be terms with gravity, but that's precisely because Russian instrumentation has fallen on hard times.In such a scenario, the two countries are perfectly placed for tangoing in space.Case study 1: The Cryogenic ChroniclesIn December 1982, ISRO set up a Cryogenic Study Team to develop cryogenic engines – which use a blend of super-cooled oxygen and hydrogen – needed for large spacecraft. The only way to master this rarefied technology quickly was to import it, as reinventing the wheel would have taken decades. Only four countries, the US, Japan, France and the Soviet Union, had this technology. The first three backed out but in January 1991 ISRO signed a deal with Russia to buy two cryogenic engines and the technology to develop them in India.Delivery was quick. The Russians supplied the cryogenic engine that had been developed for the massive N1 rocket, which had been developed for their aborted manned mission to the moon. But as soon as ISRO and the Russian scientists got down to work, under pressure from Washington, Moscow backed out.ISRO then decided to go it alone – armed with Russian blueprints and seven ready-to-fly engines earlier supplied by Moscow. Although India still hasn't mastered cryogenic technology, ISRO engineers learned to deal with new materials and manufacturing methods.Case study 2: NASA and Destination MoonThe moon is a lot wetter than we thought. According to Science magazine, conclusive proof of the presence of water molecules was delivered by India's Chandrayaan-I spacecraft which mapped the lunar surface for 315 days in 2008.It was a spectacular success story, but that's not wh ere the story ended. Enter NASA. First, the American space agency said the data on the presence of water molecules on the moon was gleaned by Indians with an instrument provided by NASA.The Americans then upped the ante. In November 2009 NASA announced its Lunar Crater Observation and Sensing Satellite, or LCROSS, had found water on the moon. The upshot – the rest of the world elided India's role in the discovery. Believe it or not, India's first lunar mission is slowly being erased from scientific, media and popular discourse.Clearly, credit is not about who got there first – as Christopher Columbus would agree – but rather who is able to smother the earlier claims.American tech: Impressive but a bridge too farSure, the implementation of American-style project management and quality assurance techniques can work wonders. It has led to impressive successes like the moon shots and the Voyager spacecraft, one of which recently became the first manmade object to exit the Solar System. American failures in space have been rare lately, pointing to a high degree of professionalism at NASA.But as in the Chandrayaan-I episode, it's hard to see NASA treating ISRO like an equal partner.Indeed, shortly after the successful launch of Chandrayaan-I in October 2008, ISRO told the media that many space-faring nations have become wary of India's rapid advances in space technology. According to the organisation, its scientists and engineers work in a "hostile environment" with other countries sharing little information and expertise.That won't change – not if you choose the wrong partner.[свернуть]
ЦитироватьPress Trust of India | New Delhi April 8, 2013 Last Upd ated at 14:55 ISTISRO planning first privately built PSLV launch in 5 yearsThe proposed national committee would look at various steps in this regard including the revenue modelMoving forward on its plans to rope in the industry in its activities, ISRO is looking towards the launch of the first privately built rocket in the next five years.The Indian Space Research Organisation has embarked on hiving off production of communication satellites and polar satellite launch vehicles (PSLVs) to the industry."We are now setting up a national committee to work out the modalities on how to go about it," ISRO Chairman K Radhakrishnan told PTI when asked about the agency's plans to rope in the industry for producing PSLVs and communication satellites.He said the space agency had told the industry representatives at a meeting in Ahmedabad in January that it was looking at PSLVs and communication satellites produced by them."My target is five years from now on. Five years from now the first PSLV will roll out from that entity," Radhakrishnan said.He said the proposed national committee would look at various steps in this regard including the revenue model, technology transfer and related matters.The space agency is keen to focus on unique science projects, develop remote sensing satellites and do more research and development instead of engaging in the repititive exercise of building communication satellites and launch vehicles.The industry participation in development of communication satellites is upto 80 per cent. If satellites and launch vehicles can be produced by industry players, ISRO scientists will be able to concentrate on research-oriented activities, and have greater involvement of academic institutions.
ЦитироватьChandrayaan was a turning point By Rekha DixitStory Dated: Monday, May 20, 2013 9:17 hrs IST Interview/ K. Radhakrishnan, Isro chairmanThe Chinese have a space station, and are sending human missions to space. India has sent a batch of six satellites into space, had a successful Moon mission and started the countdown to Mars. India's future space exploratory plans include 'Aditya' to study solar emissions and 'Astrostat', an ambitious probe to study distant stars.THE WEEK met ISRO chairman K. Radhakrishnan to get a peek into India's space plans. Excerpts from an interview:Is the India-China space race on?We are not in any race. India's approach to outer space has always been application-based and we are established leaders in our area of expertise. The Futron study, which generates the space competitiveness index [which looks at 15 countries], ranks us at sixth position. Of late, we have come to satellite-based space sciences, and lunar and planet explorations. We are leaders in having the most cost-effective missions in the world.Chandrayaan was a turning point. Now we are getting to Mars. If you look at any project in our portfolio, at the core it is people-centric, application-driven. The Chinese approach is different. They are focusing on human missions, their space station....How different will the Mars mission be from Chandrayaan-I?The biggest challenge is the distance—55 million km against 4 lakh km to the Moon. It was easy to get into the Moon's orbit by firing a rocket within the satellite itself. In the case of Mars Orbiter Mission, we will enter Mars's orbit 300 days after the launch, so complexity multiplies.Another major challenge is deep-space communication. From the Moon, signals are beamed almost instantly. From Mars, it will take 40 minutes for two-way communication. So we have to build in a high level of autonomy into the rover.MOM is fully desi, right? What about Chandrayaan-II?The only imported component will be a Sony camera, but that, too, will be adapted for the mission. Chandrayaan-II's launcher and orbiter will be ours, the lander Russian.Why did you not consider a second Moon mission before Mars?If we did not attempt Mars now, the programme would have to be pushed back to the next close Earth-Mars interface, another 26 months later.Chandrayaan-II does not have a date fixed yet, though it is slated under the 12th Five-year Plan (2012-2017). What is the status of India's human mission?We have not done much after the first study of 2006. The plan was to send a two-member crew into the Earth's orbit for a week. Such a mission requires technology which we have not done. So the current objective is to wet our hands with designing a crew module, a crew escape system, the space suit, etc. Also, a human launch requires a 'man-rated' vehicle with a reliability of .998. The government has sanctioned Rs.150 crore, which has been spent on this research.What about an Indian astronaut at the International Space Station?India is not a member of the ISS. In 2010, we received an invitation to put up an instrument there, but we need to have a good experiment. Maybe sometime....There is a feeling that our space endeavours are not trailblazers.We are trailblazers in our areas. We have the PSLV, which 16 countries have used. Our precision to target is very good, which means less fuel consumption and extended life of satellites. A 2003 study by Madras School of Economics said Indian missions cost only a fraction of what others did.We have had 103 launches so far. Of 21 space missions, there were only two GSLV failures and two satellites that did not reach orbit.There is a buzz about an asteroid heading towards Mars. Will that affect our mission?It is unlikely. There is a 1 in 12,000 chance of an asteroid coming 50,000km close to Mars. In fact, we could get the chance to look at that asteroid and its impact on Martian atmosphere.What is our space mission's future?First, we have to augment the manufacture of PSLVs. We also have to establish the reliability of GSLV. Then, we are developing the Indian Regional Navigation Satellite System of geo-positioning for the Navy and civilian users. The first of these satellites will be launched in June. Scientists are working on long-term projects like studying space debris, near-Earth objects and astro-biology, too.How has brain drain impacted our projects?Human resources have never been a constraint for our projects. ISRO alone has a strength of 16,000 people. After Chandrayaan, there is motivation among young scientists to join space research and mission activities. Attrition in the past few years is next to nil. The onus is now on us to come up with challenging projects.
ЦитироватьFr om sounding rocket to Mars Orbiter in 56 years DC | P. Radhakrishnan | 7 hours 10 min ago Polar Satellite Launch Vehicle, with a proven track record, boosts our confidence in the Mars Orbiter Mission (MOM) or Mangalyaan. But we must not forget that a mission to Mars extends far beyond the active life of the launch vehicle.PSLV will have served its part when it leaves the Mars spacecraft in a temporary elliptical (elongated) orbit around the earth from wh ere a lot more has to be done by the spacecraft itself to reach an orbit around Mars in the next 10 months.The complexity of this mission starts with the launch phase. PSLV usually finishes its common task of launching Remote Sensing satellites within about 20 minutes. On the contrary, MOM launch phase lasts nearly 45 minutes before the spacecraft separates from PSLV.The longer duration results from certain very special requirements of the mission. Once the Orbiter separates from PSLV, it is left to its own resources.The Orbiter, still going round the earth, uses its rockets to raise the orbit in 5 steps over 1 ½ months before it undertakes its 300-day journey towards Mars. Eventually the Orbiter will settle into a highly elliptical orbit around Mars in such a way that the closest distance to the red planet is about 360 km and the farthest 80,000 km.The different scientific payload (instruments) will keep observing Mars for 6 months, supplying us useful information. Remember, one-way radio communication between the earth and the Orbiter could take anywhere between 4 and 20 minutes! Most remarkably, MOM is our first venture in interplanetary space. Chandrayaan had stopped short at the Moon.First launch in 1957MOM demonstrates our long space trek since the launch of India's first artificial satellite by the Soviet Uni on in 1957. Six years later, Dr Vikram Sarabhai, the founding father of Indian Space Programme, set up a rocket launch station with international help at Thumba in Trivandrum. He had the foresight not to wait till everything was indigenously available.In those early years we launched sounding rockets borrowed from the US, Soviet Union, France and UK. Sarabhai initiated developing indigenous sounding rockets of the Rohini Series. A sounding rocket can only carry measuring instruments to a certain height in the atmosphere and afterwards it falls back. The smallest of the Rohini series was only 70 mm in diameter and the biggest 560 mm. Sarabhai died in 1971. But he had left us a great legacy – a Decade Profile for 1970-80. A highlight of the Decade Profile was the development of an indigenous satellite launch vehicle- SLV-3. Unlike a sounding rocket, an SLV steadily gains speed, and at a height, 400-500 km from the earth it ejects a satellite with a specified speed close to 7.5 km per second (about 27,000 km/hr). That makes the SLV a different animal from sounding rockets.Sarabhai's Decade Profile, among other things, also included another significant activity, namely, Satellite Communication.Sarabhai was succeeded briefly by MGK Menon and later by Satish Dhawan, who appointed APJ Abdul Kalam as the Project Director of SLV-3. The first successful launch was in 1980, after the failed launch in 1979. SLV-3 had the capability to launch only a 40-kg satellite. So an Augmented SLV (ASLV) was designed to launch a satellite up to 150 kg and this was a success.There was another collaborative programme with the Soviet Union. Aryabhata, the first satellite designed and built by us, was launched in 1975 with a Soviet launch vehicle from the Soviet Union. Aryabhata was followed by Bhaskara I and II, our first remote sensing satellites- all launched by the Soviets.Only later did we start our Indian Remote Sensing satellite (IRS) programme and the first in the series was launched in 1987 by a Soviet vehicle. The remote sensing satellites were too heavy even for ASLV, not to mention SLV-3.PSLV workhorseTo achieve self-sufficiency in remote sensing satellites, we took up the PSLV project. PSLV was designed to launch 1,500 kg remote sensing satellites into a sun-synchronous orbit passing over the poles of the earth at a height of 700 – 1,000 km. Unlike these sun-synchronous orbits, the geostationary orbit favored for communication satellites is at a height of 36,000 km above the equator. GSLV has been conceived for such communication satellites.PSLV's first launch was a failure but all the following 23 launches were successful, a glorious record. PSLV was used to launch a meteorology satellite into the geostationary orbit, and more recently for our lunar mission, Chandrayaan.During 1975-76, the Satellite Instructional TV Experiment (SITE) was conducted using a US satellite that established the feasibility of a satellite communication system for national development.That was the genesis of the late INSAT system started during Dhawan's time.But we had to outsource communication satellites owing to our lack of expertise. Ford Aerospace Corporation built first generation INSAT satellites to our specifications but we took over the second generation design and fabrication.We even decided to have the third and the fourth INSAT satellites, 1 C and D, launched by the US Space Shuttle. But before INSAT 1 C launch, Space Shuttle Challenger blew up in which seven people were killed in 1986. Two Indian astronauts, NC Bhat and I, were sel ected to fly in the Space Shuttle with INSAT 1-C and 1-D. But the Challenger disaster upset our plans. We then shifted to the European launcher, ARIANE, by far the most reliable launch vehicle today.GSLV Mk-III for 4,000 kgIn the 90's, we started developing a GSLV with a capability of launching a 2,000 kg satellite into geostationary orbit. This left us with inevitable task of developing a Cryogenic Upper Stage, without which GSLV could not do a meaningful job.We floated a global tender, to which the Russians responded, offering to sell three cryogenic rockets along with the technology at an unbelievably affordable price. So we accepted the offer but the collapse of the USSR and the American pressure on Russia deprived us of the technology clincher. Like others, we also took about 20 years to develop the cryogenic system.Our first GSLV launch was in 2001 with the Russian cryogenic stage, not a failure and not entirely a success, either. Out of the seven launches of GSLV, four failed. This is in sharp contrast to the 23 out of 24 success rate of PSLV. The importance of GSLV lies in the fact that once perfected; it can serve us for launching communications satellites weighing up to 2,000 kg.For communication satellites of more than 3,000 kg (very common for most satellites of this genre), we are in the process of developing a bigger version of GSLV, namely, GSLV Mk-III with a capability of 4,000 kg.But until it is available on an operational basis, there is no escape from depending on Ariane. At all events, early establishment of consistent performance of the current GSLV Mk-II is crucial for us. That should be the main concern for the present.(Radhakrishnan co-authored "A brief history of rocketry in ISR0" and had trained to fly aboard the US space shuttle in 1985)
ЦитироватьКосмическая программа Индии18:45 05.11.2013 (обновлено: 18:46 05.11.2013)7265 ноября 2013 года ракета PSLV‑C25 с индийским зондом "Мангальян" стартовала с космодрома имени Сатиша Дхавана для исследования Марса. Зонд успешно отделился от ракеты‑носителя и вышел на орбиту Земли. В сентябре 2014 года "Мангальян" должен выйти на эллиптическую орбиту Марса.Космические исследования в Индии начались в 1947 году, сразу после получения страной независимости. Они осуществляются под руководством правительственного Департамента космических исследований DOS (Department of Space). Непосредственная организация работ по координации деятельности различных организаций и фирм в рамках национальной космической программы, а также созданию ракетно‑космической техники возложена на космическое агентство ISRO (Indian Space Research Organization), созданное в 1962 году (до 1969 года называлось Индийский комитет космических исследований).В 1962 году в Тхумбе в южноиндийском штате Керала был построен экваториальный ракетный космодром, который стал основной площадкой для запуска небольших ракет, пока не был построен основной космодром на острове Шрихарикота (штат Андхра‑Прадеш).21 ноября 1963 года с полигона Тхумбе состоялся первый ракетный старт в истории современной Индии — была запущена американская геофизическая ракета "Найк‑Апач" (Nike‑Apache) с индийским оборудованием в головной части.В дальнейшие годы индийские специалисты приобретали опыт создания и обращения с ракетной техникой, предоставляя возможность зарубежным странам производить пуски геофизических ракет со своего полигона. В период до 1974 года из Тхумбы было запущено более 350 ракет американского, советского, французского и английского производства.Свой первый шаг в космос Индия сделала 19 апреля 1975 года, когда в СССР был запущен первый индийский спутник "Ариабхата‑1" (Ariabhata‑1).К разработке собственной ракеты‑носителя легкого класса индийцы приступили в 1973 году. Возглавлял работы Абдул Калам (Abdul Kalam), который, обучаясь в США, имел доступ к техническим отчетам по проекту американского носителя "Скаут" (Scout), ставшего прототипом первого индийского космического носителя SLV‑3 (Satellite Launche Vehicle). Первый суборбитальный полет прототипа SLV‑3 состоялся в 1976 году, а 10 августа 1979 года состоялась первая попытка запуска ракеты в космос, но она оказалась неудачной.Космической державой Индия стала в 1980 году ‑ седьмой страной в мире, запустившей собственными силами искусственный спутник Земли. 18 июля 1980 года состоялся удачный запуск ракеты‑носителя SLV‑3, который доставил спутник "Рохини" (Rohini) в космос.30 мая 1981 года в Индии была запущена третья ракета SLV‑3, доставившая на орбиту спутник "Рохини‑2". Однако спутник был выведен на нерасчетную орбиту.17 апреля 1983 года был запущен спутник "Рохини‑3".В апреле 1984 года на советском космическом корабле "Союз Т‑11" совершил полет в космос совместный индийско‑советский экипаж. Первым индийским космонавтом стал военный летчик Ракеш Шарма (Rakesh Sharma).В 1980‑е годы на базе ракеты‑носителя SLV‑3 был создан новый носитель ASLV (Advanced Space Launch Vehicle), который 20 мая 1992 года успешно вывел на околоземную орбиту "увеличенный" спутник серии "Рохини" — SROSSC (Stretched Rohini Satellite Series) массой 150 килограмм.За ASLV последовали четырехступенчатая ракета‑носитель PSLV (Polar Satellite Launch Vehicle) и трехступенчатая ракета‑носитель GSLV (Geosynchronous Satellite Launch Vehicle). Первая из них позволяет выводить на околоземную орбиту спутники массой до нескольких сот килограммов, а вторая — размещать их на геостационарной орбите.В 1990‑2000‑е годы в Индии были развернуты работы по многим направлениям космической техники. Кроме создания мощных и надежных носителей, которые позволили индийцам выйти на коммерческий рынок пусковых услуг, активно велись работы по созданию телекоммуникационных систем, по развертыванию спутниковых группировок систем дистанционного зондирования Земли.Используя ракеты‑носители собственного производства, Индия вывела на околоземную орбиту ряд спутников, в числе которых Cartosat‑1 (первый из более чем двух десятков действующих индийских спутников, предназначенных для дистанционного зондирования Земли), 24 спутника индийской системы связи INSAT, IRNSS‑1A (первый из планируемой серии спутников, предназначенных для индийской навигационной системы IRNSS), и другие.Индия самостоятельно проводит запуски спутников связи (с 2001 года), возвращаемых космических аппаратов (с 2007 года), оказывает международные пусковые услуги.В октябре 2008 года с космодрома имени Сатиша Дхавана на острове Шрихарикота был запущен первый индийский лунный зонд "Чандраян‑1" (Chandrayaan 1).Космический аппарат успел проработать на орбите Луны 312 дней, совершив 3,4 тысячи витков вокруг нее. Он передал на Землю тысячи фотографий поверхности и данные о химическом составе Луны. 29 августа 2009 года "Чандраян" передал на Землю последний пакет данных, после чего связь с ним прервалась.Продолжением индийской лунной программы является проект "Чандраян‑2", в подготовке которого принимает участие Российское коcмическое агентство.В отдаленном будущем (после 2025‑2030 года) планируются пилотируемые полёты на Луну в кооперации с другими странами или даже самостоятельно.5 ноября 2013 года ракета PSLV‑C25 с индийским зондом "Мангальян" стартовала с космодрома имени Сатиша Дхавана для исследования Марса. Зонд успешно отделился от ракеты‑носителя и вышел на орбиту Земли. В сентябре 2014 года "Мангальян" должен выйти на эллиптическую орбиту Марса с ближайшей точкой на высоте 500 километров над поверхностью планеты. Главной целью запуска является испытание технологий, необходимых для проектирования, планирования, управления и осуществления межпланетных миссий. Научными задачами миссии являются: "исследование поверхности Марса, его минералогии и атмосферы с использованием отечественного оборудования".Индия также ведет работы в направлении запуска пилотируемого корабля. Осуществить первый испытательный полет планируется в 2020 году.
ЦитироватьT E Narasimhan & Praveen Bose November 10, 2013 Last Updated at 11:34 ISTWe have to turn on Mars Mission's instruments after 300 days: K RadhakrishnanK Radhakrishnan, Chairman, ISRO , who refuses to get flustered by any situation, seemed at ease barely days before his brainchild, the Mars Orbiter Mission (MOM) would leave Earth's orbit for a 300-day journey to Mars. He sat down at his office, which is facing a lush green garden, with T E Narasimhan and Praveen Bose to share what ISRO is up to. Excerpts:You are still celebrating the successful launch of the Mars Orbiter Mission (MOM). What next?We had launched the spacecraft PSLVC25 on November 5 and we placed the Mars Orbiter spacecraft very precisely into an elliptical orbit around Earth.The perigee (the closest point to Earth) was 247 kms and apogee (the farthest point in the orbit of the Earth) was 23,563 kms inclination was what he wanted.The operations going on now are for raising the apogee fr om 23,563 km to nearly 192,000 kms and that should happen by November 16 and we have this trans-Mars injection in the early hours of December 1, 2013.During the last two days –on Thursday and Friday – the apogee was raised to 28,825 kms and perigee was 252 km, i.e. when the satellite comes to the perigee we do the firing and change the shape of the eclipse. This (Friday) morning also we had one manoeuver and apogee was raised to 40,055 kms and the perigee is now 262 kms.We have more operations planned, one is early hours on November 9 th (to around 71,000 kms) and another one is on November 11 (to nearly 100,000 kms) and then on 16 th (1.92 lakh kms).Operation on the morning of December 1, and we will impart a specific velocity to the spacecraft so that in September 2014 this spacecraft is close to Mars and that position would be 500 kms, plus or minus 50 kms.The crux of the success of the operation on December 1is we should be able to estimate precisely the velocity and the time we need to impart the velocity to the spacecraft so that it takes that position and in that the computation of the spacecraft navigation is important. How it passes fr om the sphere influence of Earth and enters a heliocentric orbit.On September 24, 2014,we have to reduce the velocity and that is the next major operation. If we are able to reduce the velocity precisely at that particular point of time, then we get the orbit and finally, the instruments will be operated.What will happen once itsets out on the long journey to Mars?Fr om now till reaching Mars, we have the Earth-bound phase and the cruising phase. We will be energising the scientific instruments. The calibration process will go on enroute. As of now, we have checked the spacecraft's subsystems, and they are working well and these two successful missions (orbit raising) also indicate that the propulsion system, and control systems are all functioning well.We are able to estimate the amount of burn required or the burn time, and how much velocity is required to reach the orbit.What were the challenges you faced for the mission?This is India's first interplanetary probe and they are very complex; and if you take India, this is presently the most complex space mission we have undertaken.Two, we are of course learning from the earlier missions.The time available from the feasibility study was quite short i.e. June 2011 to its launch in November 2013.The project was approved by the Cabinet, and Prime Minister announced it in August 2012. The requirements for the mission is that we have to execute it on the D-Day i.e. November 30 or early morning of December 1 when the spacecraft needs to leave the Earth orbit.The cushion available for us was only one or two weeks for the launch because we need to have the launch of the satellite in the first orbit by the middle of November so that we could do the orbit raising and then ready it to move towards Mars.What were the technical challenges you faced leading up to the mission?One is in terms of the complexities that needed to be addressed of the spacecraft in terms of autonomy of the craft, and in terms of the restart capability that had to be verified. The engine has to operate from the time the PSLV is put in orbit to the time the spacecraft is put in the orbit of Mars, and there is a gap of nearly 300 days between the first phase of operation, i.e. from December 1 this year to September, 2014.For the long time gap, testing had to be done over a period of time, and we have done that.For the second part, we had to build the level of autonomy in the spacecraft so that despite the communication delay (because the distance between the Earth and Mars will cause communication delays of four minutes or longer, between the spacecraft and engineers on the Earth) the spacecraft is able to manage contingencies by itself.These are the challenges we have gone through.What do you think would be most complex part of the mission?Third part of it is when you have the spacecraft of this nature reaching the orbit of Mars, 85% of the objectives are met because technologically that is the complex part and we have demonstrated that once the spacecraft reaches the orbit of Mars, we can turn on the instruments on spacecraft. We have been trying to do so from June 2011 when we started the process and identified five reliable instruments and that itself was a challenge.One, of identify the theme you require and look at instruments with the required specifications. That is another major challenge.How did you augment the infrastructure on the ground for the mission?The entire ground station needed to gear up for this. The first augmentation was made for Chandrayaan wh ere it is 400,000 kms. But here it is 400 million kms. Secondly, you require much more power to manage precious ranging and we need to bring in stations of JPL into consideration to fill up the visibility gaps.If you look at the ground station for tracking, in earlier missions we used to have at Port Blair, international location at Brunei and in Indonesia. We can see upto 23 minutes of the flight, but this is beyond 23 minutes, upto 44 minutes to monitor the critical operation of separation of the satellite and the deployment of solar panel, we required ground stations but those ground stations are on land.So we need to deploy for the first time the ship-bound ground stations and we approached the Shipping Corporation of India and got two vessels, and we had one ground station with 4.6 metre antenna system so that was fitted on SCI Nalanda and then we also got one 1.8 metre terminal of the DRDO that was fitted on SCI Yamuna and they started moving to the location in September. But since it could not reach on time, we postponed the launch by one week to November 5. These were vessels were deployed at south Pacific Ocean.These ships' performance were critical because only they would tell us about the ignition of the fourth stage and the injection of the satellite and the separation of the satellite.From June 2011 to November 2013, we had to ensure all these have been done and we have to do it on a fast track mode and the mission we are doing is complex. So we have to ensure all issues are properly addressed and necessary measures taken and then people worked almost round the clock and we had to additional tests on the spacecraft.Somebody could ask if you reduced any testing, and we have not. Instead, we added one more test which is called the thermal balance test.How do you assess the PSLV XL as a launch vehicle?On the whole, the PSLV XL has done four successful missions. But, the PSLV had to do a totally different job in this mission. You would have seen that the flight duration was nearly 44 minutes compared to 20 minutes for a normal PSLV mission because we wanted to ensure one more parameter at the point of injection i.e. "argument of perigee", which was around 282 degrees compared to 180 degrees which was put in the previous missions.So it required long coasting phase and it was coasting phase between the burnout of the third stage and the beginning of fourth stage ignition. So, the first time we were going for a long gap between the two and when you get into that kind of regime there are temperature issues that need to be understood because you will not be in the visibility of sun and second, you have to look at the satellite system once it is injected because of the thermal condition.What have done to deal with the extreme cold in outerspace?Since it will be cold, the solar panel deployment has to take place immediately after the separation of the satellite and we needed high quality solar panel mechanism for functioning the negative temperature like -26 degree Celsius, -30 degree Celsius. This is a micro level challenge; but it's critical item.If the solar panel does not deploy properly and it is a three-folder system. So, two, deployment has to take place and they have to take place as scheduled. If it doesn't take place, we have the problem of power and problem with the mission then itself.Was 15 months justifiable for such a mission?We did not start from zero, there are a lot of things known to us as far as the mission is concerned, and orbit-raising operations around Earth are known and we have been doing it from geo stations for the GSLV, GSAT and Insat. If you look at orbit-raising and moving towards a different object outside the Earth's gravity we did it with Chandrayaan and we have that experience.Number two, if you talk about a general spacecraft bus, we have the heritage of the former missions in communication, and remote sensing. What you require in that is a large delta that is what we were doing it and ensuring that the total system is in place.Yes, the time is tight, but it has been done.If you look at the normal way of working, it was an impossible schedule; but when you are determined to do it and the teams are giving their best for their project, then you can say nothing is impossible and you can do it.How did you manage these at a lower cost (compared to others)?If you take India's space programme in general budget for the programme is small and noting the fact that ISRO is one of the first six space agencies, including NASA, Russia, European Space Agency, Japan, China and ISRO. Last few years we are at six.Our budget is 7.5% of NASA's budget and that is one indicator.What is the secret then? One, there is an outlook for each of these agencies, and if you look at Russian programme, they have a large number of launches taking place. They believe in building robustness in the rocket and they don't worry about optimisation and they have a large vehicle and it can be produced in large quantities. But, for that they do extensive amount of testing on the ground on different articles, and they conduct several tests. So this is one philosophy. But their systems are very robust.In American system, generally you can see optimisation and if you look at India from the SLV III, Aryabatta's time from the '70s we have been following the modular approach (one project, feeds into next one). In space system, always perigee is essential and that is you should see a system that has performed well in the space orbit. So, modular approach also helps and once you do the modular approach it may not be the optimum because given free hand to you, you would have designed slightly differently so that you can get the best out of it. But in the modular approach what happens is you have a reliable system coming into it, and that is already development which is taken place and getting fed to a new system.For example, in '70s we had the SLV III that was a four-stage rocket, we also had a communication satellite programme called Apple. That was the first communication satellite we built and here the satellite had to be launched by Arianespace in its second developmental flight to a geostation transfer orbit and we have to make it as circular an orbit using a small rocket put into the Apple spacecraft.Are there any learnings from that period implemented now?Now the job of the liquid engine, we see in the Mars Orbiter or Geostation satellites, was done at that time by a solid motor and that solid motor was the fourth stage of SLV III. Suppose we decided that time to develop reductive engine, that would have been an ideal choice, but it would have taken time. Here we could feed from one programme, a module that was developed into another programme. This is one of the early experiments we had, one is the necessity and second, one you take that approach and do additional testing. The basic development is done.How are the launch vehicle programmes progressing?Our launch vehicles are the PSLV, GSLV and GSLV Mark III. We need to look at their configurations.PSLV development started in 1982; the feasibility study was done in 1979 by Late S Srinivasan, former study director and first project director. Approval came from the government in 1982 and first developmental flight was in 1993; of course that was the only failure in the PSLV and in 1994 first successful flight of PSLV injected a remote sensing spacecraft IRS IE of 850 kgs.Imagine, 1979 to 1994 we had been in a development phase. All the systems were developed, tested and how did it get into the next programme is the story.S139 stage in PSLV today, originally it was with slightly with lower propalene S125, you augmented. The same was used in the GSLV, so the core of the GSLV first stage is the same S139 so it means there were no extra development effect required. If you look at the second stage of the PSLV, based on liquid engine and that engine is Vikas. The legacy of Vikas starts with the French space programme wh ere for the Ariane development programme they developed a Viking engine and during the development phase our Indian engineers sel ected from Isro worked with the organisation called SAP France for about three years. In the process they acquired technology. It's a beautiful arrangement, wh ere you don't transfer money for this purpose, work with them and acquire technology and we realised that engine in India. Along with the Indian industry participating and as of now we have nearly produced 120 engines and we made the second stage of the PSLV using this engine and over the years we also improved this engine and enhanced its capacity.One engine and the stage arranged around that.If you look at the GSLV configuration, we made the best use of this technology. We used the same stage for the second stage of GSLV.GSLV also required augmentation. If you look at the lower portion of the GSLV, second stage, core of the first stage and strap-ons it is derived from the development effect of the PSLV. If we had started fr om the knowhow got a configuration of the GSLV and used the best for that, it would have required different configuration, and in a different phase of development. For the GSLV, we have to worry about the cryogenic engine.What do you lose in the process ?Because we adopted the configuration, modules which are tested and proved only one small difficulty; the L40s (liquid) and core S139 (solid) are together. The core 139 will complete its job before L40 finish its job. So what happens for some period is that the dead weight of S139, that is the chamber, is also carried. Ideally what we do is one stage does its job and we separate it so that it does not have to carry; this is the small penalty we are giving for taking testing modules and reliable module.New module would take time.GSLV Marl III, the core of liquid stage L110 and its based on twin-engine configuration, since it has to fire longer, so we have to worry about the nozzle, thermal aspects and all and that stage is configured.
ЦитироватьAnd, about the satellites...A spacecraft can be divided into two sections, one is the platform and the second one is the payload. We have different capacities for the platforms, if you look at communication we had one tonne, then we became two, 3.5 now and we are going to six tonnes.So if the platform is proven, then you will change only the payloads. That means you will have standard sets of platforms.You seem obsessed with the schedules.The other aspect, when it comes to cost is we are obsessed with our schedules. In Isro, it is always told who fixes the schedule and target for us, and we put that. For example, we could have done the Mars Mission in 2016 or 2018. But we decided that in the first opportunity we will do it and then we worked towards that. If we have five or ten year schedule, the way you go towards that to achieve it is totally different and it also has cost and that is one of the keys to our success.The schedules which are fixed are also optimistic and normally we achieve around that. If we have to keep the momentum of any project it has to be on a fast track; everybody should be galvanised to meet that and you should see events take place and only then can people be galvanised.How do you control costs?When you are obsessed with the schedule and not much schedule overruns, again the cost will come down.Third one is that we are always novel in our approach. Somebody may call it a new terminology, but whatever it is we use a novel approach. Chandrayaan, for instance, had to reach 14 kms per second velocity embedded to the spacecraft; but we achieved it in an efficient way. We used the launch vehicle to provide part of it using the PSLV and the remaining part was provided by the spacecraft propulsion system, which is more efficient.Working culture, novel method, modularity, optimisation of test, obsession with quality and salary of people all these help to make the missions cheaper compared to other space organizations.What was your approach in case of the Mars Mission?Like what we are seeing today, we did not launch the orbiter into the 200,000 kms apogee, we are going step by step and if you look at the total energy you consumed to give the velocity of 9.8 kms per second, it was given by the PSLV itself and the subsequent 1.6 km per second by the fuel in the spacecraft itself; fr om November 5 to December 1 we can see a nice picture emerging.For the 9.8 kms per second velocity for that spacecraft we needed an entire PSLV XL vehicle; now the remaining part is done by a small liquid engine which is sitting in the spacecraft and the consumption of the fuel will be very less and more efficient.This is the novelty of this mission, instead of directly putting into the orbit. Spacecraft propulsion system is importantTo raise the apogee fr om 23,563 kms to 192,000 kms we are using around 340 kgs of fuel stored in the spacecraft to impart it a velocity of nearly around 1 km per second.The PSLV XL was 320 tonnes and you have to use it to reach that orbit.We used the propellant capability to raise the orbit, from here towards the Mars.Ideally, we could have gone for a higher apogee; but we would have used a bigger rocket, but we used a small novel approach.Was it the novel approach used for Chandrayaan too?Yes, and that is why the GSLV was not used, and PSLV is the answer.Minimum energy is used to transport it in a certain geometry on earth and mars orbit, that's why we insist on time for the current shape.For 30 days we had a launch window, and we generated a trajectoryThe next part of it is extensive amount of ground testing to qualify in the new system; several test optical and others. What we do is we get the maximum out of the test we do. We designed the test such a way that you get the maximum information out of that test, so that the number of tests can be brought down; that means you save money and time.With such tight schedules, can you describe Isro's work culture?We are different in working style, and people put in 18-hour days. During launch, people take just four hours rest.They give their blood to the programme and organisation. Passion and obsession are on the programme.In one of the missions, four days before the launch the mission authorisation board had cleared the vehicle for the project. Then, the project director's father expired; he went there and completed the funeral and came back and he conducted the mission, and the launch was completed and then he went back. He is the mission director, and all others are around him. He is the one who gives the key. But, it is not an isolated case.People don't worry about their annual vacation, casual leave, events etc., Many launches came at a time when there was a festival. But people work. They have passion to work.This is how impossible becomes possible.Because of Mars Mission did Isro slowed down other missions or work?No. we have 16,000 people working with Isro and from late '80s our numbers have gone up, though we also have industry supporting us.While the number of missions have been going up, manpower did not increase.From 1975 to 2009, we did 82 missions (29 launch vehicles and 53 satellites), 2010 to 2013 in four years we did 27 missions i.e of 109 missions over the last 38 years, 27 have been done in the last four years.Mars Mission feasibility study was done in August 2010; during the period we can see the performance. These are also complex satellites and newer machines like microwave remote sensing satellites or the navigation satellites.How many launches planned?We have 18 missions lined up. Up to March 2015, in 15 months, we have lined up 18 missions.No mission in the previous years or the missions in the future were affected because of the accelerated way of working. In fact, we have had the accelerated way of working everywhere.Of all the missions we have done in the last four years, some of them were new and all the launches were done at Sriharikota, if it's our launch vehicles.There's been a quantum jump in other programmes in the last 3-4 years.We had 82 in 35 years vs 27 in four years, and we have not compromised. Each programme will have its own problems like technology or project issue.Can you compare the PSLV and GSLV?From 1993 to 2013, we have had 25 flights of PSLV. Except for the first one, all were successful. Over these years we have enhanced the capacity of the PSLV. Initially it was to put 850 kg remote sensing satellite. For the same PSLV we augmented the capacity by improving the propulsion system and we also improved the avionics, and made it a better systemToday, it can launch 1,850 kg microwave remote sensing satellite; to that level we have stretched capacity.GSLV experience has been slightly bitter. It was not very successful like the PSLV. Of the seven flights three failed.What tests have been doing on the engine front for the GSLV?In 2003 we tested the engine and in 2007, we qualified the stage. In the last three years. we did 20 ground tests. We tested the fuel booster turbo pump. We have been testing at higher altitudes and we have been working on it on a war footing. In February 2012, we decided to do the high altitude simulated testing. We tried to augment our facilities for testing the GSLV cryogenic engine. It was considered impossible to do it in one year. But, eventually we did it In March, and we held two tests at the facility. Again work is on at Mahendragiri on high altitude testing. We had to do extensive changes to the facility so that at high altitude conditions, it works.What are your worries on the heavy lift vehicle (GSLV)?First and foremost worry is that the launch vehicle, the GSLV and the second is that of the cryogenic stage.We have qualified both the solid and L110 tonne liquid stage, which is a high-powered stage. When we do a test on the cryogenic stage... priority is on the cryogenic stage and cryogenic engine. Till we get this right we will not have the capability to launch four-tonne class satellite, and till then we will have to depend on Ariane for launching communication satellites in the 4 tonne class. Now, this in a good stage. We have to exploit its potential. In March, 2014 we plan a launch. We have to look at the vehicle in toto. Right now aerodynamic stage testing is on.We have issues with transponder capacity. How do you plan to augment it?For transponder capacity, we use a three-pronged approach. One, we build a communication satellite of 3.5 tonne class and then get it launched from abroad. Second, we use the PSLV and launch 2 tonne class satellites. Three, use foreign transponders. We have foreign transponders now. We now have new capabilities.After Mars, what's your immediate task?The Mars mission has a long way to go. But, it's not massive in nature, though it has to be precise. The velocity has to be precise. It has not been done so far. For the GSLV launch in December 2013, we have seen all plans through.Is there any convention yet on Mars exploration? What's ISRO done?We should not create pollution there. There's no convention yet with regards to Mars as there is with the moon. As of now there are few exploring it. In future, we see such a convention coming just like the moon treaty. In case of Mars we can have a geo-satellite. But, this is a different class. We can have an inter-planetary fly-by (like the Voyager of NASA).Where could we go from here on Mars?The next one is the orbiter. This will help us take a closer look at the planet. The third, is to land there. It can be a soft or hard landing. In case of Chandrayaan, it came down by itself. If landing is precise, it will be soft landing.The next is that of sample returns. The spacecraft can take samples and bring it back. But, it needs the mechanism to store it and bring it back. That's the next level of complexity. The next is the human flight to Mars.What are the kind of collaborations ISRO could consider?There could be collaboration in the areas of lunar exploration, and for exploring the sun and Mars explorations. We can have a larger mission. We are able to do that. The next one has to be a more complex mission. We did a joint project of building a satellite with the French called Meghatropique a while ago. We had worked with the French on developing two landers.We have now done a joint study with NASA's Jet Propulsion Laboratory (JPL).What's the joint study with JPL all about?With the JPL, the study is on microwave remote sensing. It's about the study of pulse and know what is not normally visible cloudy conditions, for instance If cloud is there. In remote sensing, depending on the frequency one can identify what's there by depending on frequency characteristic change. For instance, the 'L' band studies vegetation. Another one, the S band gives another study. Or, the X band gives another feel. We have done studies with the C Band. In the project with JPL, we look at both L and S band.The spacecraft will be made by us. There's a very large antenna required which will be a 12 metre diameter antenna. This will be launched by 2019-20. In the second phase, we do the project report preparation. Then, we work on satellite together.On the Chandrayaan. NASA brought instruments. In this case it will be a collaboration. Both agencies will work together.Please describe the benefits derived for people from the findings of ISRO.The Madras School of Economics did a study 2000-03 study that studied the tangible and intangible benefits from ISRO's work. How communication is structured, and how disaster management reports are studied. It has direct and indirect economic benefits and also intangible benefits are derived. It is cost-effective, if it is made in that. On the application side, it has gone into many areas. A few more areas are to be done. If you look at fishermen, using the surface temperature data we give daily forecasting on the right place to find food catch. The information is displayed on the notice board in fishing harbours. You find many fishermen using GPS now for a good catch based on the information we provide.These are areas wh ere fish is in plenty. Some days you get a good catch. We carry the announcements in each language in the coastal areas, such as in Tamil, Malayalam, Kannada, Telugu, Konkani, Oriya, Bangla and any other language spoken in the respective areas. In Andaman & Nicobar and Lakshadeep too we provide the information. It gives direct benefit to millions of people. There are about 100,000 fishing vessels. If fishing vessels can get precise data, then savings on vessel diesel is huge.Now it's an active season for agriculture. In agriculture, we use remote sensing to estimate crop production. We use technology and put it in a model. The Mahalanobis Centre for Crop Forecast in New Delhi uses ISRO's data. We also look at water resources. The GSI uses it for information on land area. One can get large-scale mop, for instance 1: 10,000. Planners use it to see what is it they need to do to optimise the impact their work. It helps in Informed decision-making. The budget on this is Rs 50,000-60,000 crore.In case of ground water, using conventional method, one may derive only about 50% of the water that once can get. Features like faults for example can be found. In this method, the success rate is 90%. Maps help people to locate wells in right place. If a farmer spends Rs 1 lakh and gets water, that's a direct benefit.Also, in the '70s, thousands of people died in cyclones. Now it is reduced because ISRO is able to provide timely information.
ЦитироватьRocket motors destroyed in fire at Sriharikota space centreUpdated: November 15, 2013 02:32 IST Staff Reporter Rocket motors worth Rs. 1.5 crore were reportedly destroyed by fire at the solid propellant plant at the Satish Dhawan Space Centre (SDSC SHAR) in Sriharikota, here on Thursday.Central Industrial Security Force personnel detected smoke billowing from a store room at the plant, which manufactures solid propellant rocket motors that the Indian Space Research Organisation uses in launch vehicles.Sources said a short circuit caused the fire, which did not spread to other rooms in the facility. The destroyed equipment belonged to the Hyderabad-based Premier Explosives Ltd.
ЦитироватьEx-scientist of ISRO bats for Kulasekarapattinam DC | 17th Nov 2013 Picture for representational purpose only. Chennai: Veteran Indian Space Research Organisation scientist and former chief general manager of liquid propulsion system centre at Thiruvananthapuram, N. Sivasubramanian, along with locals, on Saturday met and urged Union minister of state in Prime Minister Office V. Narayanasamy to take steps to establish the third rocket launch centre at Kulasekarapattinam in Tamil Nadu.One of the members of the team, which met the minister, later told Deccan Chronicle that the minister had assured them that Sriharikota has not been finalised for the third rocket launch centre. The minister was also learnt to have assured suitable action in the coming session of Parliament to set up the rocket launch centre in the village in southern Tamil Nadu.Earlier, DMK president M. Karunanidhi wrote to the PM, highlighting the advantages of establishing the centre at Kulasekarapattinam.Meanwhile, DMK Rajya Sabha MP Kanimozhi has approached the Prime Minister and Congress vice-president Rahul Gandhi to bring the rocket launch centre to Kulasekarapattinam, which is only 40 km fr om the liquid propulsion system centre at Mahendragiri from wh ere most of the equipment would be mobilised for satellite and rocket launches.
ЦитироватьPrint edition : February 7, 2014 Interview: K. Radhakrishnan GSLV MkIII, the next milestone K. BHAGYA PRAKASH K. Radhakrishnan , Chairman of Indian Space Research Organisation (ISRO). Interview with K. Radhakrishnan, Chairman, Indian Space Research Organisation. By R. RAMACHANDRANFOLLOWING THE SUCCESSFUL LAUNCH OF GSLV D5/GSAT-14, Frontline caught up with K. Radhakrishnan, Chairman, ISRO, on January 10 in New Delhi. In the conversation, Radhakrishnan discussed the various problems faced in the development of cryogenic systems and how these were overcome to prepare the organisation for its next big challenge, a success with GSLV MkIII, which will be powered by an entirely indigenous cryogenic engine and stage, and is targeted for 2015. Excerpts:What elements of the Mark II cryogenic engine and stage, which fired GSLV-D5, still retain the legacy of Russian engine technology and design? How much of it is truly indigenous and how much of it relies on the Russian heritage?Basically, both engines use the "staged combustion cycle". That is one approach compared with gas generator cycle, which we are using for the C20 engine to be used in GSLV MkIII. There are several other differences, conceptually also, especially the igniter system that we are using, which is totally different from what has been used in the Russian engine. [In MkII liquid oxygen (LOX) and gaseous hydrogen (GH2) are ignited by pyrogen-type igniters in the pre-burner as well as in the main and steering engines during initial stages, as against pyrotechnic ignition in the Russian engine.] But in the staged combustion cycle, similarities can be found in the way the engine is started and the steering engines are used for controllability.But the staged combustion cycle itself is quite complex.The staged combustion cycle is complex but it gives slightly improved performance in terms of the specific impulse [Isp]. But in the gas generator cycle, you have the ability to test the individual elements. So if you look at the reliability aspects—establishing a reliable system and the time required for that—we can work in parallel. The issue is relevant in the context of GSLV MkIII, for which we were working on the engine and stage elements in parallel. The turbo pump, which has something like 5 megawatt of power, has already been tested and it has logged about 1,400 seconds on the ground. We have tested the thrust chamber along with the injector, igniter and the nozzle. We did two tests, and the third test is being done today [January 10]. [This test, which lasted for 50 seconds, was as predicted and was successful.] Now, when we have sufficient knowledge about the ignition characteristics, the combustion instability aspects and performance in different regimes of [LOX+liquid hydrogen, or LH2] mixture ratio, then we can start with engine test and then the stage test. So the time required from now to qualifying the stage becomes less. This is the main advantage. The flexibility that is available in a gas generator cycle is much more because individual systems can be tested from the input/output point of view and they can be qualified in parallel. In the previous situation, the stage process was started after the engine qualification. The second aspect of the GSLV MkIII engine is that we are gimballing the nozzle for thrust vector control [and not the two using vernier (steering) engines as in the Russian engine and the cryogenic upper stage (CUS) of the indigenised MkII]. So we are only concerned about two ignitions, that is, the main engine and the gas generator. In the case of GSLV MKII's CUS, the two steering engines have to ignite before the main engine ignites and that feed has to come from the main line. Unless the right temperature and pressure conditions are there at the beginning of that process, the steering engines will not function. In fact, in some of the ground tests, we noticed the problem of a two-phased flow. The most important part of the cryogenic engine is the sustained ignition and the termination of the turbo pumps. It should not give any undue rate for the spacecraft. So in this launch, the engine start was as predicted; the four ignitions were as predicted; similarly, the termination was also as predicted. If you look at the performance of the subsystems, the turbo pumps—the main turbo pump, the oxidiser turbo pump and the fuel booster turbo pump—in both the regimes—the uprated regime and the nominal regime—plus the temperatures, all have been well within the specifications. All the components that it employs, too, have performed well.In retrospect, considering that it has taken such a long time, could we not have used the gas generator cycle?No. At that time, before 1992, we were working with a one-tonne engine. We were learning cryo at that time; the learning started in 1982. If you trace the history, in the early 1970s, when the Space Science and Technology Centre was there in Thiruvananthapuram, in the pre-SLV3 stage, we were trying to understand all these propulsion systems, including hyper-propulsion, semi-cryogenic propulsion, and cryogenic propulsion. But then the essential focus was on the SLV-3 programme, which had solid propulsion in all the four stages. And that was essential for the programme. So, in 1992, the approach was technology acquisition. We followed a path and we continued with that.What is the gain in Isp in the staged combustion cycle?It is only of the order of 10 seconds.The one-tonne engine and the subsequent indigenous work were all based on the gas generator cycle. So it would seem that just for that little gain we seem to have embarked on a highly complex technology that has taken such a long time to absorb.It was complex but at that time it was the only one that was available. We now know that the flexibility available in the gas generator cycle is enormous. It is a learning process.The GSLV has seen several failures and there must have been a lesson to be learnt from each one of them. If you look at the first flight [GSLV-D1], essentially it was related to the mixture ratio used for the Russian cryogenic stage as far as the vehicle was concerned. In the aborted launch that took place [three weeks] earlier [March 28, 2001], essentially it was because of the blockage in one of the feed lines [by a lump of lead in the NO (dinitrogen tetroxide) feed line of the strap-on (S3) liquid engine L-40's gas generator]. The latter called for tightening of the assembly and inspection processes. In the second [GSLV-D2] and the third [GSLV-F01] launches, there were no issues. In the next launch [GSLV-F02], there was again a fabrication issue. A dimension was not inspected during the manufacturing process. When that component [of the strap-on S4] was tested, a deviation was seen but that was taken as a wild point, something to do with the facility. It was too abnormal because we got a flow rate almost nine times what was expected. It was an annular gap which was supposed to be 0.5 mm. Something which was to be 17 mm was made 16 mm, and because of this dimensional change, what was to be 0.5 mm became 1.5 mm, resulting in an increase in the area [3x3] and hence the flow rate. That's what happened.If you look at the PSLV's first flight, which failed, when we did the simulation on the ground, there was a wild point even at that time. Only one out of some 1,000-plus simulations, but it was taken as a wild point and ignored. So the lesson that we learnt is that wild points are not to be ignored but to be studied. They are an indication of something else that is happening. In F04, the control system of a strap-on stage failed because a gas motor stopped. This has again to do with the component and has nothing to do with the vehicle design. In GSLV-D3, it was again a component problem. All four ignitions started, but it was a pump [fuel booster turbo pump] that stopped. Why did the pump stop? We looked at three scenarios and the contamination theory was the most likely because we found the source of that contamination. It was a propellant acquisition system [PAS], which is basically a filter that ensures that the propellant gets into the outlet.The initial theory was that there are three bearings, and a normally assembled motor is tested under standard room conditions and not in cryogenic conditions. And when the pump goes into cryogenic temperatures, there will be contraction. Since there are different materials, there would be dissimilar contractions. So tolerances are provided so that the bearing will not stop. But we found that the calculation might not have been done accurately. But the issue is, if it touches [something],will it stop, because there is a lot of power given to it? So we decided to test this in cryogenic conditions. A test facility was created. We did not take [the theory] for granted.The second scenario is that a welding could have failed and the casing could have come out. We would have had a similar condition then. The possibility of a casing coming out was, however, very remote. But still we redesigned it. We made a casting. The third scenario was contamination. We did not want to get locked on to the contamination theory because then we may not see the other things. The PAS is imported and is kept in a sealed cover. When we vibrated it, we found foreign particles coming out. Then we had to do a lot of cleaning and so that was the reason. So we decided to redesign it and that is what we used in D5. Otherwise, the liquid hydrogen tank itself could provide that contamination. All these three issues that we came across have been corrected. So it is a component-level problem and a not system problem. In F06, it was an inspection problem. The cryo-stage shroud, which is expected to move a little bit during the vehicle movement, is supposed to be provided with a lanyard of about 15 mm. But it was almost not there. It was only about 1-2 mm, resulting in greater tension. Two connectors are provided. But both connectors came out. And then we lost the signal from top to bottom. This is what happened actually.The question is what did we do to address these. Compared with the PSLV, in the GSLV we have a large number of fluid components that have to work in flight. So we make the system, test it and use it and then after some time fly it. In this process, the leak rate would increase sometimes if there are very small defects. So getting a component assembled and tested properly becomes very important. We have tightened that now. In the recent PSLVs also, we have a good record in this area. We have introduced a zero-defect delivery system, which essentially boils down to the person who assembles the component. The technician who assembles the component should be aware of the impact of even a small scratch on a sheet or a dust particle coming into the system or something he might miss during the assembly. We introduced training about one and a half years ago and it is given in situ at the work spot in the local language with examples. When we say that the components have all performed to specifications during the entire campaign, it is actually the result of this. So this is the lesson from the GSLV. Otherwise, the GSLV per se, compared with the PSLV, is a better vehicle. Cryo is complex. Leave that part. If you take the bottom stages, the number of propulsion systems and control systems that come into the picture is far smaller. The only issue there is the solid motor hardware, which will have to be carried for nearly 40 seconds by the strap-ons because that does not separate. The advantage is that proven stages are being used here.What is the next important milestone for the GSLV?The immediate thing is GSLV MkIII, the experimental mission with the passive cryo stage.What do you mean by passive cryo?No engine will be burnt in the third stage. Actually, if you look at the GSLV, 50 per cent of the velocity is given by the non-cryo portion. So we will get about 5 km/s velocity, and it will be a suborbital flight. But what we want to test here is the atmospheric phase of the flight. While it is coming down, we will use it to characterise the crew module. We can measure the thermal stress when it is coming down. As far as the vehicle is concerned, its exterior will be ditto. Internally, the cryo will be passive.
ЦитироватьSurprise at Isro: Govt appoints Shailesh Nayak as ad hoc chairmanArun Ram,TNN | Dec 31, 2014, 06.39 PM ISTSources told TOI that the appointment is only for a month, after which he may be asked to continue or a new chairman may be brought in. K Radhakrishnan, who was given an extension earlier this year, retired on Wednesday.CHENNAI: In a surprise move, the government has appointed Shailesh Nayak, secretary in the ministry of earth sciences, as the ad-hoc chairman of Indian Space Research Organisation (Isro).Sources told TOI that the appointment is only for a month, after which he may be asked to continue or a new chairman may be brought in. K Radhakrishnan, who was given an extension earlier this year, retired on Wednesday.Nayak, 61, a geologist from MS University, Baroda, had a stint in Isro till 2000. He was earlier the director of Indian National Centre for Ocean Information Services (Incois), Hyderabad.While Radhakrishnan has been on an extended tenure, the names of Satish Dhawan Space Centre director M Y S Prasad and Space Application Centre director Kiran Kumar were making the rounds, but Prime Minister Narendra Modi found merit in neither of them.As Isro enters a crucial phase of planning manned missions and interplanetary exploration, scientists feel, the organisation needs a strong person at the helm, preferably someone who straddles rocket science and administrative skills."This seems to be an ad hoc measure," said a senior Isro scientist. "If the idea was to have an interim chairman, the incumbent could have been given a month's extension."
ЦитироватьNew Delhi: The Indian Space Research Organisation (Isro) successfully tested an indigenous cryogenic engine on Tuesday which will allow launch vehicles to carry satellites of up to four tonnes.Congratulating the scientists on the successful testing, Prime Minister Narendra Modi said on Twitter, "The engine tested today will enable us to put satellites of up to 4 tons in geostationary orbit. A proud accomplishment."Although the Geosynchronous Satellite Launch Vehicle (GSLV Mark III) successfully launched an unmanned capsule that could be used for manned missions in December, it had a passive cryogenic stage. While GSLV Mark III is India's largest launch vehicle, carrying up to four-tonne vehicles will only be possible with a cryogenic engine with the capacity.India has till now been dependent on foreign launch vehicles to send heavier satellites to the required orbits. "There was a special test set up in Mahendragiri to see if the engine developed the exact thrust required to launch payloads of that weight. It succeeded," an Isro spokesperson told Mint on the phone."Now we'll have to prove if this engine can be used in a launch vehicle," the spokesperson added. Mahendragiri in Tamil Nadu is home to the Isro Propulsion Complex, where cryogenic engines are tested.India has been on a long arduous journey to develop an operational indigenous cryogenic engine which began around 30 years ago. The first success came in January last year, when India successfully launched GSLV-D5, marking the first successful launch of a vehicle with an indigenous cryogenic engine. But India at present can only launch satellites of up to two tonnes.
ЦитироватьTHIRUVANANTHAPURAM: A scaled-down, unmanned version of India's futuristic space shuttle is getting the final touches at the Vikram Sarabhai Space Centre (VSSC) in Thumba.With the construction of the Reusable Launch Vehicle-Technology Demonstrator (RLV-TD) nearing completion, A S Kiran Kumar, chairman, Indian Space Research Organisation (ISRO), is scheduled to lead a review of the dream project here on Friday."The 'space plane' part of the RLV-TD is almost ready. We are now in the process of affixing special tiles on its outer surface which is needed for withstanding the intense heat during re-entry into the earth's atmosphere," SSC director M Chandradathan said."The entire construction of the RLV-TD is being handled by VSSC," he said.ISRO has tentatively slated the prototype's test flight from the first launchpad of Sriharikota spaceport for July this year, but the date would be finalised depending on the completion of construction. The proposed RLV is designed in two parts; a manned space plane rigged atop a single stage, booster rocket using solid fuel. The rocket is expendable while the RLV would fly back to earth and land like a normal aeroplane after the mission.The prototype - 'the RLV-TD' weighs just 1.5 tonnes and would fly up to a height of 70 kms.For the test mission, the unmanned space plane part would glide into the Bay of Bengal a la the recent crew module successfully tested aboard the Geosynchronous Satellite Launch Vehicle Mk-III (GSLV Mk-III) experimental flight last year.India's answer to the space shuttle, the RLV is one of the big steps forward in ISRO's launch vehicle programme along with the GSLV Mk-III and the Unified Launch Vehicle project.ISRO has successfully tested re-entry technology twice- the first time in 2009 with the Space Capsule Recovery Experiment-1 (SRE-1) in January 2007 and the second with the Crew Module Atmospheric Re-entry Experiment (CARE) aboard the GSLV Mk-III in December 2014.