By Gp Capt Joseph Noronha
29 Aug , 2016
ISRO is aware of the looming challenge. Perhaps that is why it is already making efforts to rope in a private Indian consortium to manufacture its workhorse PSLV. It is also working to remove bottlenecks and looking to adding a new vehicle assembly building. Its aim is to triple PSLV launches from about six to 18 a year. This is a good beginning. But ISRO cannot rest on its laurels if it is to retain the tag of “the lowest-cost satellite launch agency in the world” and what is more, it knows this.
Sriharikota in Andhra Pradesh on the coast of the Bay of Bengal is a barrier island that has come to be intimately linked with India’s space exploration dreams. It was on May 23, 2016, that a pioneering launch from Sriharikota’s Satish Dhawan Space Centre (SDSC), operated by the Indian Space Research Organisation (ISRO), made news around the world. Five years after the United States retired its small Space Shuttle fleet, following 133 missions, ISRO dared to attempt a launch of its own shuttle technology demonstrator. And what is more, it succeeded.
A slow-burning nine-tonne solid-fuel rocket lifted the 6.5m long scale model of the winged Reusable Launch Vehicle (RLV) weighing 1.75 tonnes to an altitude of about 70 km. Travelling initially at Mach 5, the RLV, made a decelerated glide as planned into the Bay of Bengal. At least two more such prototypes will be extensively tested before the operational version, which may be around 40m long, is ready to fly. Naturally, it must be able to make a soft landing on a runway to qualify it for prompt reuse. That may be by around 2030.
Thanks to PSLV, all the nation’s remote sensing and navigation satellites are now launched domestically…
More recently, on June 22, 2016, ISRO again made history by launching 20 satellites, including some from the US, Germany, Canada and Indonesia, in a single mission from the SDSC. The main payload was India’s latest earth observation Cartosat-2 series satellite. The total weight of all 20 satellites was about 1,288 kg. It was a complex mission and the biggest single-rocket launch by ISRO, trailing Russia’s 37 in 2014 and America’s 29 in 2013.
Currently, 35 Indian satellites are operational, of which 13 are communications, 13 earth observation, seven navigation and two space-sciences related. ISRO’s own assessment is that twice this number is required.
According to Wikipedia, ISRO has launched a total of 84 Indian satellites till June 2016, using indigenous launchers as well as US, Russian and European rockets. And as landmark ISRO missions come thick and fast, success is now almost taken for granted. It wasn’t always so.
Bright Spots and Blurs
ISRO was set up on Independence Day in 1969, less than a month after the US Apollo 11 astronauts set foot on the surface of the Moon for the first time. But ISRO’s roots go deeper. In 1962, the government established the Indian National Committee on Space Research (INCOSPAR) under Dr Vikram Sarabhai to formulate the national space programme. It set up the Thumba Equatorial Rocket Launching Station (TERLS) near Thiruvananthapuram and began by launching simple sounding rockets.
Once ISRO took over, it began to work to a plan to accelerate the country’s space activities and ultimately achieve self-sufficiency. On April 19, 1975, the first Indian satellite named Aryabhatta was launched from the USSR by an Interkosmos rocket. Meanwhile, a new launch pad was set up at Sriharikota and on July 18, 1980, Satellite Launch Vehicle-3 (SLV-3) successfully blasted off and placed a 35-kg Rohini satellite, RS-1, in Low Earth Orbit (LEO). The SLV series was followed by the larger Augmented Satellite Launch Vehicle (ASLV) series, intended to place 150kg satellites in 400-km circular orbits. However, both the SLV and ASLV families were largely unsuccessful.
ISRO has operationalised GAGAN that aids aviation by refining GPS signals to a three-metre accuracy…
Yet ISRO kept going, carefully analysing and remedying its shortcomings and changing tack when necessary. And its doggedness ultimately paid off in the Polar Satellite Launch Vehicle (PSLV) series.
Polar Pride
It is nice to have the reputation of being as reliable as the world’s best and ISRO has deservedly won that tag thanks largely to its workhorse PSLV. This was actually ISRO’s first operational launch vehicle, capable of hurling a 1,600kg satellite into a 620km sun-synchronous polar orbit or a 1,050kg satellite in Geo-synchronous/Geo-stationary Transfer Orbit (GTO). It is responsible for some of ISRO’s most spectacular triumphs including the mission to Mars and to the Moon.
The PSLV’s first launch in September 1993 was a failure. However, since then, the rocket has had a dream run of 35 consecutive successful launches (one was partly successful). ISRO’s main focus has always been utilitarian – putting into orbit what is needed for the country’s development. Thanks to PSLV, all the nation’s remote sensing and navigation satellites are now launched domestically, far cheaper than it would have otherwise cost. Without the PSLV, the Indian satellite constellation would have been vastly smaller.
Between January 1996 and June 2016, the PSLV launched 39 Indian and 74 foreign satellites, indicating ISRO’s growing international acceptance as a small satellite launch agency. But the limited payload of PSLV means that India needs a heavier rocket to achieve its major space goals, even indigenously orbiting communications satellites. This is where the record is still patchy.
GSLV – Getting There
The Geosynchronous Satellite Launch Vehicle (GSLV) was launched for the first time on April 18, 2001, and has seen nine missions so far. GSLV is designed to lift a 5,000kg payload into LEO or a 2,500kg payload into GTO. The heavier GSLV Mk-III that features an indigenous cryogenic third stage has a higher payload capacity of 8,000kg to LEO or 4,000kg to GTO. In comparison, the heaviest launcher ever built, the US National Aeronautics and Space Administration’s (NASA) Saturn V could lift up to 140 tonnes to LEO. This is not to downplay ISRO’s achievements but to serve as a reality check.
Not all GSLV launches have been successful. On April 15, 2010, GSLV D-3 with crucial indigenous cryogenic technology was being tested for the first time. However, the vehicle strayed from its designated path when the cryogenic stage underperformed and it went spinning out of control. Just eight months later, on December 25, GSLV F06, carrying a precious payload, the GSAT-5P communications satellite, had to be destroyed 63 seconds into its mission when it failed to develop its rated thrust and veered off course.
India probably has the largest civilian remote sensing satellite constellation in the world…
Following these twin failures, ISRO went back to the drawing board. And the next two GSLV launches in January 2014 and August 2015 were perfect. GSLV, and especially its Mk-III version, is crucial to many of ISRO’s plans, including manned spaceflight. For that it must prove its reliability by more flawless launches, beginning with one later this year.
ISRO’s Major Achievements at a Glance
Moon: India’s first Moon mission, Chandrayaan-1, was conceptualised and built entirely by ISRO. It was launched aboard the PSLV-XL-C11 with larger strap-on motors on October 22, 2008. The payload included instruments from several countries. Chandrayaan-1 was successfully inserted into lunar orbit on November 8, 2008, and operated until August 2009. The mission included a lunar orbiter that studied the Moon at close quarters and revealed significant amounts of water, and an impactor that delivered the Indian tricolour to the surface.
Mars: Mars has been the graveyard of many space ambitions so the world sat up and took note when India sent an unmanned orbital craft to the planet in 2014, courtesy PSLV-XL-C25. ISRO’s Mars Orbiter Mission (MOM), Mangalyaan, reportedly cost just $73 million compared to the $670 million price tag of America’s Maven Mars mission. Mangalyaan entered the Martian orbit on September 24, 2014, 300 days after lift-off, making India the only nation to succeed in its first attempt to send a spacecraft to the Red Planet.
Indian Remote Sensing (IRS) System: On March 17, 1988, IRS-1A, the first satellite in this series was launched. The latest Cartosat-2C (launched June 22, 2016) was the 15th remote sensing satellite to be successfully orbited. India probably has the largest civilian remote sensing satellite constellation in the world and imagery obtained is useful for cartographic purposes, urban, rural, and coastal land use, water distribution and many other practical applications.
Indian National Satellite (INSAT) System: The largest domestic communications satellite system in the Asia-Pacific region began with the August 30, 1983, launch of INSAT-1B. In all ISRO has orbited 24 communications satellites of the INSAT and the more advanced GSAT type, many by the European Ariane launch vehicle. These satellites are designed for telecommunications, television broadcasting, weather forecasting, disaster warning, and Search And Rescue (SAR) operations. Hundreds of TV and radio stations across India depend on these satellites for their feed.
GPS-Aided Geo Augmented Navigation (GAGAN) System: ISRO has operationalised GAGAN that aids aviation by refining GPS signals to a three-metre accuracy. It offers seamless satellite navigation to air traffic and provides precision approach facility to aircraft landing at Indian airports.
Indian Regional Navigational Satellite System (IRNSS): One of the brightest feathers yet in ISRO’s cap is the seven-satellite IRNSS navigation system, the last of which was orbited on April 28, 2016. Three satellites are in geo-stationary orbits above the Equator, and four are in geo-synchronous, elliptical orbits that keep them permanently within view of ground stations. Each has a navigation payload and a ranging payload.
India is frequently accused of wasting money on its space endeavour when it still has so many poor people…
At present, only two such systems are operational globally – the US Global Positioning System (GPS) and the Russian Global Navigation Satellite System (GLONASS). Europe’s Galileo is partly operational and is likely to be fully operational globally by 2019-2020. China’s BeiDou-2 (Compass) is operational in the Asia-Pacific region and expects to go global by 2020. As Prime Minister Narendra Modi put it while naming the system NAVIC, or Navigation With Indian Constellation, “India is now proudly among five nations in the world which have established their own satellite navigation system. Until today, we were reliant on GPS and systems from other nations, but today we are independent.” Once again ISRO did it cheaper than any other nation. NAVIC is interoperable and compatible with the GPS and Galileo systems and GAGAN supports it too.
Military Matters: The advanced countries have long exploited the military potential of space and India too is taking steps in this regard. However, ISRO needs to operationalise its GSLV to be able to launch satellites weighing over two tonnes – the minimum necessary for a significant military payload. India currently has only one exclusive military satellite in space. GSAT-7, launched in 2013, is an indigenous multi-band communications satellite that helps the Indian Navy to maintain surveillance over the waters surrounding the country. Next on the cards is a dedicated Indian Air Force satellite, GSAT-7A, designed to interlink all IAF ground and airborne assets and strengthen the Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) infrastructure.
Reusable Launch Vehicle (RLV)
The high cost of rocket fuel coupled with single-use rockets makes the profitability of satellite launches rather low. It also means launches cannot be frequent and inhibits the use of space. That is why determined attempts are being made to master reusable space technology.
As Elon Musk, CEO of SpaceX, puts it, “If one can figure out how to effectively reuse rockets just like airplanes, the cost of access to space will be reduced by as much as a factor of a hundred. A fully reusable vehicle has never been done before. That really is the fundamental breakthrough needed to revolutionize access to space.” Both SpaceX and another US corporation Blue Origin have made good progress in testing reusable launch vehicles. On December 21, 2015, the first-stage of SpaceX’s Falcon 9 rocket successfully landed upright on solid ground, for the first time, following an orbital launch. Blue Origin’s New Shepard booster achieved the same feat earlier, but off a sub-orbital mission. On April 8, 2016, another SpaceX rocket made the first ever soft landing on a robot ship in the Atlantic Ocean.
ISRO has a fairly modest target of bringing down launch costs to a tenth of current figures…
Also under development are Stratolaunch, an enormous air launch carrier aircraft, and other aircraft-based systems that hope to tap the growing launch market for small to medium-size LEO satellites.
That is why ISRO is pursuing its RLV-TD, a two-stage to orbit reusable launch vehicle. Following the first flight in May, in the second test an aircraft will drop the RLV-TD high in the atmosphere to complete an autonomous runway landing. In the third, the RLV-TD will be launched normally and then made to land like an aircraft on a specially built five-kilometre long runway. This is crucial for RLV to be fully reusable. In the fourth test, the RLV-TD will be powered by a scramjet engine. In a scramjet (supersonic combusting ramjet) combustion takes place in supersonic airflow. It relies on high vehicle speed to forcefully compress the incoming air before combustion. Ultimately, the RLV-TD will have to perform at a speed of Mach 25 using scramjet propulsion.
Then will come the hard part – scaling up the experimental shuttle to practical proportions. It is the equivalent of transforming a basic jet trainer into a Boeing B747. ISRO can learn from NASA’s mistakes – especially not to attempt to design the same vehicle to launch satellites and carry astronauts as this can drastically reduce the payload capacity. Technology has also progressed and ISRO may be able to use stronger and lighter materials for its shuttle, thus reducing time and expense for each turnaround. ISRO has a fairly modest target of bringing down launch costs to a tenth of current figures and it is optimistic enough to anticipate break within 25 to 50 launches.
ISRO is also considering an Advanced RLV (ARLV) with a very slim structure. The vehicle may have semi-cryogenic boosters internally, plus a scramjet engine.
Future: Humans in Space and Other Missions
The government is happy to proclaim the frugality of ISRO’s missions – how they cost a fraction of what NASA and other space agencies spend…
The US, Russia and China have all put humans in space and the ISRO has never hidden its ambition to do so. A few years ago, there was even a tentative launch date for the first crewed mission: 2015-2016. But that was before the heart-breaking GSLV failures. Unless ISRO succeeds in “man rating” the GSLV i.e. certifying the launch vehicle and its space capsule as fit to carry astronauts, the nation’s first manned spaceflight mission will remain a mirage. Now that it has a couple of successful GSLV missions under its belt, ISRO can dare to hope again. If all goes well, 2021-2022 now seems the earliest realistic possibility for the first mission.
On a relatively more modest scale, Chandrayaan-2, a heavier and more capable craft, is planned for the next Moon mission. It will have an indigenous lander and rover that will collect and analyse soil samples and send the data back to earth. It is scheduled for launch by early 2018. A follow-up mission to Mars, called Mangalyaan-2, is likely around 2020. It too will have a greater scientific payload and may even include a lander and a rover. ISRO also plans a mission to the Sun around 2019-2020. Aditya-L1, weighing about 400kg, will be launched aboard PSLV-XL and placed in a halo orbit around the Lagrangian point L1 of the Sun-Earth system. From there it will have the major advantage of continuously viewing the Sun without any occultation or eclipse.
Money Makes the Mare Go
Call it a race or competition, the high-risk and high-stakes space launch field is an arena of international rivalry. The US, Russia and Europe have reached where they are by investing huge sums of money. China, which was a late entrant, is now making spectacular progress, backed by an ambitious leadership and substantial funds. It is simultaneously working on two new launch vehicles – Long March-7 and Long March-5. Long March-5, a next-generation heavy-lift rocket with 25-tonne to LEO or 14-tonne to GTO payload capacity, is planned to land a craft on Mars in 2021 to coincide with an important Chinese national anniversary. Other major missions are expected before then, including the Chang’e 5-T1 probe to bring back soil samples from a lunar pole around 2017 and the launch of the core module for China’s own space station around 2020.
In contrast, ISRO knows its budget is limited and emphasizes economy. It has learned from the mistakes of others and capitalised on low labour and operating costs to produce world beaters that don’t cost the Moon. It has made full use of its freedom to pursue excellence, unlike most government departments that are plagued by corruption, waste and sloth. When foreign ‘nannies’ denied it critical space technologies, in the wake of India’s Pokhran-II nuclear tests, ISRO remained unfazed. It turned the situation to its advantage by developing its own cryogenic engines and other systems such that today it is remarkably self-sufficient.
India is frequently accused of wasting money on its space endeavour when it still has so many poor people but ISRO’s efforts to put space to practical use have reaped rich developmental dividends. Various national agencies source data from ISRO for a variety of applications including predicting the monsoon, forecasting crop yields and providing advance warning of food shortages. To get such data from foreign agencies would cost much more.
The government is happy to proclaim the frugality of ISRO’s missions – how they cost a fraction of what NASA and other space agencies spend. But while this is fine for technology demonstrators it is unlikely to hold good for missions like human spaceflight where cost cutting might result in a disastrous accident. In a nutshell, ISRO needs more investment, both public and private. Until now, ISRO has been in competition with national space agencies – of the US, Russia, the EU and China. Its main run of success has been with PSLV that occupies a niche launch area with limited competition. It has earned about Rs 4,400 crore from foreign customers for its launches until July 2014. But competition is emerging on many fronts, especially from well-funded American corporations. And how many instances are there on record where the public sector been able to ward off determined private enterprise?
ISRO is aware of the looming challenge. Perhaps that is why it is already making efforts to rope in a private Indian consortium to manufacture its workhorse PSLV. It is also working to remove bottlenecks and looking to adding a new vehicle assembly building. Its aim is to triple PSLV launches from about six to 18 a year. This is a good beginning. But ISRO cannot rest on its laurels if it is to retain the tag of “the lowest-cost satellite launch agency in the world” and what is more, it knows this.
© Copyright 2016 Indian Defence Review
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