India's Space Shuttle

ISRO's RLV-TD

INTRODUCTION:

Sriharikota Range, popularly known as SHAR is situated on an island off Sullurupeta - a small town in Nellore district, of the state Andhra Pradesh. This launch centre located at Sriharikota island, was named as Satish Dhawan Space Centre, SHAR (SDSC, SHAR) in September 2002, in memory of Prof Satish Dhawan, who was Chairman of ISRO from 1972 to 1984. The activities at SDSC, SHAR are grouped under vehicle assembly and static test operations, range operations, liquid storage and service facilities and, solid propellant space booster plant. However, the most fascinating events that take place in this quaint location are the launches of giant rocket boosters. Unknown to many, ISRO is getting ready to launch a  high tech Reusable rocket, a capability which has no players but has aspirants aplenty.

BACKGROUND:

The Space Capsule Recovery Experiment (SRE-1) is an experimental spacecraft launched by ISRO in 2007, it is designed to demonstrate the capability to recover an orbiting space capsule, and the technology of an orbiting platform for performing experiments in micro gravity conditions. It was also intended to test reusable Thermal Protection System, navigation, guidance and control, hypersonic aero-thermodynamics, management of communication blackout, deceleration and flotation system and recovery operations.

The SRE-1 comprised of an aero-thermo structure, mission management unit, altitude sensors, inertial measurement unit, S-band transponder with unique belt array antenna embedded to ATS, power and electronics packages to support deceleration and flotation system. It also housed two microgravity payloads. The parachute, pyro devices, avionics packages of triggering unit and sequencer, telemetry and tracking system and sensors for measurement of system performance parameters were placed inside the SRE-1 capsule which performed flawlessly. All the above technologies will be applied in the Reusable Launch Vehicle Technology Demonstrator (RLV-TD) experimental vehicle.

Reusable Launch Vehicle Technology Demonstrator (RLV-TD):

A winged Reusable Launch Vehicle Technology Demonstrator (RLV-TD) has been configured to act as a flying test bed to evaluate various technologies, viz., hypersonic flight, autonomous landing, powered cruise flight and hypersonic flight using air breathing propulsion towards realising a Two Stage to Orbit (TSTO) fully Reusable Launch Vehicle.

Major milestones reach for the RLV-TD include:

• Completion of major actions identified by the National Review Committee during the Integrated Technical Review (ITR) of hypersonic experimental flight (RLV-TD HEX-01).
• Mission analyses on the design of trajectory, autopilot and guidance have been completed.
• The Avionics Bay powering for the Avionics packages in the Technology Demonstrator Vehicle (TDV) was carried out through Checkout System and On-Board Checkout Computer (OBCC).
• The second phase of the full scale Flush Air Data System (FADS) model was successfully tested and validated at the Wind Tunnel Facility, IIT, Kanpur with modified algorithms and recalibrated sensors.
• Radar Altimeter along with antenna was also validated through a Balloon test at TATA Institute of Fundamental Research (TIFR), Hyderabad and the capability of the system has been demonstrated.
• Trial assembly of Thermal Protection System for qualifying the bonding procedure and trial assembly of Booster with Interstage and TDV have been completed.
• The realisation of the flight hardware and its assembly and integration is in progress. The launch of RLV-TD HEX-01 mission is planned in 2014.

FIRST DEMONSTRATION FLIGHT:

The first test flight of the RLV-TD called as RLV-TD HEX-01 (Hypersonic Flight Experiment) is expected to occur in the month of March 2015. RLV-TD alone without the Solid Booster weighs about 3 tonnes, with a diameter of about 0.56 m and a length of about 10 m. The RLV-TD will be mounted on top of a S-9 Solid Rocket Booster (SRB) which weighs about 9 tonnes.

The main objectives of this test flight are:

1 - Validating the aerodynamic design characteristics during Hypersonic flight.

2 - Characterize induced loads during the Hypersonic re-entry into the atmosphere.

3 - Recovery of the HEX vehicle from the sea.

4 - Assess the performance of the carbon fibre used in construction of the nose of the vehicle.

5 - Demonstrating First Stage separation sequencing.

RLV-TD HEX-01 is the first out of four in the series of test flights. HEX-01 stands for Hypersonic Flight Experiment.The other four tests are:

1 - LEX (Landing Experiment)

2 - REX (Return Flight Experiment)

3 - SPEX (Scramjet Propulsion Experiment)

The conventional satellite launch vehicles PSLV and GSLV are not cost effective. Hence, currently efforts are being made to develop Reusable Launch Vehicle (RLV). The proposed vehicle is a two stage to orbit configuration with a semi-cryogenic winged booster and a cryogenic ballistic orbiter in which the first stage will fly back to the landing site near the launch pad like a conventional aircraft. It will serve as a flying test bed to evaluate various technologies such as hypersonic flight, autonomous landing, powered cruise flight and hypersonic flight using air breathing propulsion.

The S-9 Solid Rocket Booster (SRB) undergoing tests at Liquid Propulsion Systems Center

The RLV-TD will possess wings and tail fins, and will be launched atop a 9 ton solid booster called S-9, similar to the ones on the PSLV.  RLV-TD is reported to be 9m long, with its wing span also measuring 9m. The RLV-TD plus the S9 Solid Rocket Booster stack will together weigh 12-ton. Following liftoff, the S-9 booster will climb to 100-km and accelerate several times the speed of sound with the RLV-TD. RLV-TD will then separate and glide down using its fin and wing controls and will land in  the Bay of Bengal, close to the shore.  The water landing is planned because India doesn't have a long enough runway which is more than 5 Km in length.

The next experiment would be to land the vehicle on a 2km runway after releasing it from an aircraft from a height of about 5km. The third step would be to take it to a higher altitude and try the ground landing.

SCRAMJET FLIGHT TEST:

Indian Space Research Organisation has developed a hydrogen based scramjet engine. All the ground based tests have been completed using the moderate size hypersonic wind tunnel and the conventional shock tunnel available within ISRO. The flight tests using the sounding rockets will commence shortly.

HYPERSONIC TECHNOLOGY DEMONSTRATOR VEHICLE (HSTDV):

This program is to demonstrate a scramjet engine integrated vehicle performance in autonomous mode. In addition to proving the design and performance of the scramjet engine the HSTDV will also be able to prove the associated technologies including aerodynamic design, aero-thermal design, materials and hot structures at hypersonic flight Mach numbers. The HSTDV mission involves launching the hypersonic air-breathing vehicle called Cruise Vehicle (CV) to a Mach number of 6.5 at an altitude of 30-35 km using a rocket launch vehicle. A single scramjet engine burning kerosene fuel powers the cruise vehicle for a sustained operation of 20 second duration.

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India's Quest for MIRV Technology - Analysis

Multiple Independent Targetable  Re-entry Vehicle (MIRV)

US is a nation is preoccupied with its national interests and priorities more than any country on this planet, and this singular protocol seems to have inspired China, to robust emulation. As a mark of its new found power status the Chinese seem to be everywhere in and around the Asia-Pacific region. This crusade of belligerence and posturing is redefining standard foreign policies processes of many countries, specifically India, Japan, South Korea, Taiwan, Philippines and Vietnam who seem to have certain levels of niggling region. China's has been progressively increasing its defense budget vis-a-vis development of sophisticated weapons and defense related equipment over the last few decades. The result is China has introduced an appalling assortment of arms of sundry magnitude, China is also on the cusp of deploying Multiple Independent Re-entry Vehicle (MIRV) on their ballistic missiles, a development that is likely to have profound and pervasive outcome for the region and beyond.

What is a MIRV?

 

US Minuteman III MIRV ICBM launch sequence: 1. The missile launches out of its silo by firing its first-stage boost motor (A). 2. About 60 seconds after launch, the 1st stage drops off and the second-stage motor (B) ignites. The missile shroud (E) is ejected. 3. About 120 seconds after launch, the third-stage motor (C) ignites and separates from the 2nd stage. 4. About 180 seconds after launch, third-stage thrust terminates and the post-boost vehicle (D) separates from the rocket. 5. The post-boost vehicle maneuvers itself and prepares for reentry vehicle (RV) deployment. 6. While the post-boost vehicle backs away, the RVs, decoys, and chaff are deployed (this may occur during ascent). 7. The RVs and chaff reenter the atmosphere at high speeds and are armed in flight. 8. The nuclear warheads detonate, either as air bursts or ground bursts.

The US during the whetting era of cold war developed a uniquely dangerous weapon able to strike anywhere in the Soviet Union at wanton. The missile an MIRV also carried decoys and chaffs to evade air defense systems. This new technology undermined the entire balance of power between the two superpowers and struck fear into hard hearts of Soviet citizens.

The military purpose of a MIRV:

• Provides greater target damage for a given missile payload. 
• A multiple independently targetable reentry vehicle (MIRV) warhead is a collection of nuclear weapons carried on a single intercontinental ballistic missile (ICBM) or a submarine-launched ballistic missile (SLBM). Using a MIRV warhead, a single launch can strike several targets, or fewer targets redundantly. 
• With single warhead missiles, one missile must be launched for each target. By contrast with a MIRV warhead, the post-boost stage can dispense the warheads against multiple targets across a wider area. Theoretically at least, only a small portion of an adversary’s missile force would be necessary to completely eliminate one’s strategic deterrent.
• MIRV is destabilizing force primarily because they give nations greater confidence to destroy the enemy's critical missile sites in a first strike action by launching multiple, lower yield warheads.
• Reduces the effectiveness of an anti-ballistic missile system that relies on intercepting individual warheads. Thus, in both a military and economic sense, MIRVs render ABM systems less effective, as the costs of maintaining a workable defense against MIRVs would greatly increase, requiring multiple defensive missiles for each offensive one. 
• Decoy reentry vehicles can be used alongside actual warheads to minimize the chances of the actual warheads being intercepted before they reach their targets.

Why India needs MIRVs?

Agni-5 is capable of launching 4-5 multiple warheads, whose yield is unknown. Although it is not clear if the government has gone ahead and cleared the developed of MIRV system, former head of India’s DRDO, V.K. Saraswat, noted that several Agni variants could eventually be developed with this capability. Development of MIRV technology is vital to India's National Security because of potential threats from hostile adversaries, besides it will strengthen its aspirations of a complete nuclear triad and lastly it compliments India's minimum nuclear deterrence policy. Pakistan’s aggressive postures and China’s belligerence toward India in the recent past necessitates such an indispensable step. The deployment of MIRV technology will quantifying India's nuclear deterrence and enhance defence preparedness

Can India develop the Technologies involved?

The building blocks from boosters to radars, seekers and sophisticated mission control centers are currently available. DRDO had been able to develop key Radio Frequency seeker technologies for missiles, it has since indigenously perfected this technology, and digital processing during the missile's boost, mid-course and terminal phase is based on DRDO’s own software. The RF and Infra Red seekers are meant for proximity and precision engagement of targets, and both these technologies are required for the anti-ballistic missile (ABM) capability apart from other missiles as well. India is working on a new seeker technology with other countries also. Today, India is able to design and develop RF seekers, and in about a year or so, it will be independent in this key technology. Coming years would see greater Indian investment in micro-electro mechanical systems (MEMS), nano-sensors, nano-materials and advanced information technology tools. Such advancements would be essential for creating reliable, robust and highly accurate systems like the MIRV. This technology would enhance India’s nuclear deterrence capabilities. 

Cutting-Edge Techs

Weapon Dispersion

Analyzing a ballistic trajectory is a simple physics problem, but there is big difference betweem analysis and implementation. Recording the necessary data, rapidly analyzing it, combined with ever changing variables, to determine the precise moment to release a warhead so that it hits a specific target 8-10 thousand miles away, is not a simple task. Therefore, dispersing nuclear warheads is another major technological challenge.

China developed a method for deploying multiple satellites under a contract with Motorola. The deployment method utilized a "smart dispenser" to place Iridium class communication satellites into orbit and the know-how was transferred from Lockheed Martin Corporation. Another auxiliary technology required is the availability of expendable perigee/apogee kick motors, these are small booster motors set to lift satellites into higher orbits. 

However, India had developed both these technologies locally much before the Chinese cloned it. The PSLV-C20 launch in February 2013 is very significant because for the first time 7 satellites were inserted into their precise orbits using an embedded System-on-Chip (SOC) method, and the same SOC methodology is used for Agni-5 to assist its accuracy during its guidance and terminal phases. A notable point is that ISRO and DRDO have tested this key MIRV prerequisite by stealth which had clear military implications.

Miniaturization 

Miniaturization of nuclear and thermonuclear weapons as has been obtained to fit the nose cone spatial shape of Agni missiles. Weapons design and testing has to be simulated in a virtual environment using Super Computers since actual testing stands frozen after Pokhran-II. It must be assumed that BARC scientists have achieved the level of miniaturization deemed adequate and suitable 20 KT fission warhead.

Re-entry Design

All missile launch planning begins with a set of requirements that has to be met to achieve mission objectives. The re-entry phase of a mission is no different. There is a very delicately balance of three, often competing, requirements:

• Deceleration
• Heating 
• Accuracy of landing or impact

Modern ballistic trajectory nuclear weapon system delivery vehicles typically utilize slender sphere-cone geometries with multiple warheads on a single delivery bus. For a given warhead and associated arming device, the designer selects the re-entry vehicle base diameter and vehicle length, which effectively determines the cone half-angle. The nose bluntness ratio is then selected based on drag and heat transfer considerations. The delivery vehicle has to sustain high high aerodynamic stress (deceleration) and heating, hence it must be made of advance materials. Although the agencies have worked extensively on aero-thermal structure and thermal protection system designs over the past decade for both its space and missile programs, its effective use on MIRV platform is yet to be ascertained.

Other prerequisites

• Robust guidance and control computers with adequate computational abilities to conduct complex maths
• Develop advanced and accurate inertial guidance systems such as gyroscope and accelerometers for precise and decisive targeting.

Conclusion

It is evident from history that there exists a close concurrence between space and missile programs as was the case with both the Soviet Union and America. China and India have also pursued the same path. The interchangeability of several technologies between the two entities suit there sustained development, but the more pronounced beneficiary is undeniably the missile program. Though the Indian missile program has matured to world-class levels, it is mastering some of the above technologies that will make MIRV integration as a holistic deterrent system.

by Admin

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IRNSS Satellite Navigation System: Explained

Introduction

Since the beginning of time, human beings have looked to the sky to determine their whereabouts. Traditionally, the Sun and the pattern of fixed stars have been their guides. But in the second millennium, constellations of man-made satellites have taken over as beacons to guide the way.

What is satellite navigation?

Using the fixed stars, you can determine your position anywhere on the Earth’s surface to within a few hundred meters provided the weather is fine. But navigation satellites can tell you where you are to the nearest few meters or better, whatever the weather. Enhanced instruments can even pinpoint the position of a stationary object to within a few centimeters by measuring the object’s position many thousands of times over several hours and then working out the average of the measurements. Sophisticated new receiver technology picks up signals transmitted by navigational satellites. The receiver technology is small enough to be incorporated into the electronics of a car or mobile phone, and all our lives are changing as a result.

A satellite navigation is a system of satellites that provide autonomous geo-spatial positioning with global or regional coverage. The signals also allow the electronic receivers to calculate the current local time to high precision, which allows time synchronisation. A satellite navigation system with global coverage may be termed a global navigation satellite system or GNSS.

American Global Positioning System (GPS) technology is widely available for vehicles and smartphones. GPS was originally developed in the United States for defense related applications, way back in the 1970s, GPS services became available to civilians in the 1990s. The technology is based on the user's receiver picking up precisely timed radio signals from orbiting satellites, and calculating its distance from each source. Since the signals also communicate the position of each satellite in its orbit, the device can combine the information to pinpoint the location of the user in three dimensions. The precise time signals from the constellation of satellites - 32 in total for GPS - can also provide accurate time and synchronization data for mobile phones and networks.

Some of the major Satellite Navigation Systems are the Global Positioning System (US), GLONASS (Russia), Galileo (Europe), Indian Regional Navigation Satellite System (IRNSS), Quasi-Zenith Satellite System (Japan), Doppler Orbitography and Radio-positioning Integrated by Satellite-DORIS (France) and BeiDou-2 (China).

Indian Regional Navigation Satellite System (IRNSS)

Satellite Navigation service is an emerging satellite based system with commercial and strategic applications. ISRO is committed to provide the satellite based Navigation services to meet the emerging demands of the Civil Aviation requirements and to meet the user requirements of the positioning, navigation and timing based on the independent satellite navigation system. To meet the Civil Aviation requirements, ISRO is working jointly with Airport Authority of India (AAI) in establishing the GPS Aided Geo Augmented Navigation (GAGAN) system. To meet the user requirements of the positioning, navigation and timing services based on the indigenous system, ISRO is establishing a regional satellite navigation system called Indian Regional Navigation Satellite System (IRNSS).

(a) GPS Aided GEO Augmented Navigation (GAGAN):

This is a Satellite Based Augmentation System (SBAS) implemented jointly with Airport Authority of India (AAI). The main objectives of GAGAN are to provide Satellite-based Navigation services with accuracy and integrity required for civil aviation applications and to provide better Air Traffic Management over Indian Airspace. The system will be interoperable with other international SBAS systems and provide seamless navigation across regional boundaries. The GAGAN Signal-In-Space (SIS) is available through GSAT-8 and GSAT-10.

(b) Indian Regional Navigation Satellite System (IRNSS)

This is an independent Indian Satellite based positioning system for critical National applications. The main objective is to provide Reliable Position, Navigation and Timing services over India and its neighbourhood, to provide fairly good accuracy to the user.

IRNSS will provide basically two types of services:

• Standard Positioning Service (SPS)
• Restricted Service (RS) 

Space Segment consists of seven satellites, three satellites in GEO stationary orbit (GEO) and four satellites in Geo Synchronous Orbit (GSO) orbit with inclination of 29° to the equatorial plane. All the satellites will be visible at all times in the Indian region. The first satellite is scheduled to be launched in 2013 and the total seven satellite constellation is scheduled to be in place by 2016. Ground Segment is responsible for the maintenance and operation of the IRNSS constellation. It provides the monitoring of the constellation status, computation of the orbital and clock parameters and navigation data uploading. The Ground segment comprises of TTC & Uplinking Stations, Spacecraft Control Centre, IRNSS Timing Centre, CDMA Ranging Stations, Navigation Control Centre and Data Communication Links. Space segment is compatible with single frequency receiver for Standard Positioning Service (SPS), dual frequency receiver for both SPS & RS service and a multi mode receiver compatible with other GNSS providers.

Some applications of IRNSS are:

• Terrestrial, Aerial and Marine Navigation 
• Disaster Management 
• Vehicle tracking and fleet management 
• Integration with mobile phones 
• Precise Timing 
• Mapping and Geodetic Data Capture 
• Terrestrial navigation aid for hikers and travellers 
• Visual and voice navigation for drivers

Courtesy of IDN

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Why GSLV MK-III success matters?

India's Crew Module Atmospheric Re-entry Experiment (CARE) flew to an altitude of 78 miles (126 km). CARE then separated from the upper stage of the GSLV Mk-III rocket, and landed over Bay of Bengal on Dec. 18, 2014

Significance of GSLV MK-III

• It is the most capable rocket ever developed by India. It can carry up to 10 metric tons, or about 22,000 pounds, of cargo into low Earth orbit and up to 4 metric tons or about 8,800 pounds into geostationary transfer orbit once it is operational.
• Validated complex atmospheric ascent regime, especially aerodynamic and control features that cannot be conclusively tested on ground.
• Validated new design features which includes both Hardware and Software implementation
• Performance validation of S200 solid boosters which generate 1.1 million pounds of thrust, making them the second-most powerful solid-fueled rocket motors currently in service after the strap-on rockets used by Europe’s Ariane 5 launcher.
• Successfully tested 2 liquid-fueled L110 clustered Vikas engines using hydrazine as fuel which ignited when the rocket is already in the air, firing for more than three minutes and ramping up to peak power of 360,000 pounds of thrust. This is the first time ISRO has tested a clustered engine configuration.
• The launch marked the successful testing of the atmospheric re-entry of a crew module, which separated from the rocket 325 seconds after lift-off at an altitude of 126 km, and descended in ballistic mode, re-entering the Earth’s atmosphere (about 80 km above sea level) and splashing down into the Bay of Bengal.
• 1,600 degrees Celsius is the temperature that the CARE module withstood at re-entry into atmosphere, advanced heat shield technology was employed, further analysis of the data will reveal the actual temperature signature prevalent during re-entry phase.
• Re-entry capability is key to sending a human into space. This is a complicated and dangerous manoeuvre; it is while re-entering the Earth’s atmosphere that the space shuttle Columbia was destroyed in 2003, killing seven astronauts, including Indian American Kalpana Chawla.
• Finally, the global space industry is worth more than $ 300 billion, apart from the regular PSLV business and India has the potential to tap a substantial portion of this large pie once the GSLV matures as a reliable & credible launch platform.

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Major Achievements of ISRO Year Ended 2014

Introduction

The Indian Space Programme had a modest beginning with the launch of the first sounding rockets in November 1963 from the Thumba Equatorial Rocket Launching Station (TERLS), an obscure fishing village near Thiruvananthapuram for the investigation of ionosphere using sounding rockets. The primary objective of the Indian Space Program is to achieve self-reliance in Space Technology and to evolve application program to meet the developmental needs of the country, thus ISRO was brought under the newly formed DOS in September 1972. 

Since then, over the last five decades, the ever challenging task of space technology development and utilisation, has not only graduated from experimental and demonstration phases to an operation era, but also provided its potential to address the national needs. Notable progress has been made in the design, development and operation of space systems, as well as, using them for vital services like telecommunications, television broadcasting, meteorology, disaster management support and natural resources survey and management including climate variability and change.

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Know All About India's First Mars-Bound Spacecraft ‘Mangalyaan’

Mission Objectives

One of the main objectives of the first Indian mission to Mars is to develop the technologies required for design, planning, management and operations of an interplanetary mission. 

Following are the major objectives of the mission: 

A. Technological Objectives:

• Design and realisation of a Mars orbiter with a capability to survive and perform Earth bound manoeuvres, cruise phase of 300 days, Mars orbit insertion / capture, and on-orbit phase around Mars. 
• Deep space communication, navigation, mission planning and management. 
• Incorporate autonomous features to handle contingency situations. 

B. Scientific Objectives:

Exploration of Mars surface features, morphology, mineralogy and Martian atmosphere by indigenous scientific instruments. 

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Major Orbital Launch Systems of the World

ORIGIN: INDIA

Images: ISRO

INTRODUCTION

The Indian Space program, since its inception, has been guided by the vision of Dr Vikram Sarabhai, considered as the father of Indian Space program, he laid emphasis on the application of space technology for finding solutions to the problems of the common man and the society at large. Self-reliance in space technology has been the important motto and goal for India's policy makers. In 1969, Dr. Vikram A Sarabhai created the Indian Space Research Organization (ISRO). Since then ISRO has been remarkably successful with the active participation of several great scientists and administrators. ISRO is the nodal agency to manage and implement all space related activities in India. The services in communication, broadcasting, meteorology, military reconnaissance, interplanetary and Lunar missions are now been provided by spacecrafts designed and built in India. They have also mastered the elusive and exclusive Cryogenic technology and conversely building Semi-Cryogenic stage as well and shortly poised to launch heavier boosters to place satellites in the 5-ton class. India has pursued a reasonable and a well-balanced program, nicely adapted to the nation's developmental needs. While ISRO has put together a systematic rocket launch vehicle building program, they have also significantly concentrated on the two of the most important areas for a large and developing country such as India, building telecommunications and remote sensing applications.

PSLV: The Polar Satellite Launch Vehicle (PSLV) is the workhorse rocket of ISRO with an outstanding success rate among medium lift rocket systems. The success of the PSLV is an important milestone for the Indian space industry. India has achieved self-sufficiency in launching its operational satellites. The PSLV is a unique vehicle which employs both liquid and solid fuel engines, and it is ISRO's workhorse. The PSLV can place a satellite weighing about three tonnes in low earth orbit (LEO), at a height of 400 to 600 km. It can also deploy satellites weighing up to 1,500kg in Polar Sun Synchronous orbit at a height of 750km above the earth. This versatile and flexible vehicle can handle a LEO, a polar and a GTO orbit. The Payload capacity to Low Earth Orbit is 3,250 kilograms (7,170 lb) and Helio-Synchronous or Sun-Synchronous Orbit is 1,600 kilograms (3,500 lb) and to Geostationary Transfer Orbit is 1,410 kilograms (3,110 lb). The vehicle configuration is as follows, total height is 44 meters (144 feet), diameter is 2.8 meters (9 feet+) and Gross Mass is 295 tons. The first-stage or the core stage employs solid fuel with a total thrust of 486Kn with a specific impulse of 269 seconds with a total burn time of 105 seconds. The fuel used is Hydroxyl-Terminated Polybutadiene (HTPB). The core stage is mated to 6 solid strap-on boosters (only in the PSLV-G and PSLV-XL versions) using HTPB as fuel. The second-stage employes 1 Vikas liquid engine using Unsymmetrical Dimethyl Hydrazine (UDMH) and Nitrogen Tetroxide (N2O4) as fuel, and the third-stage is also a solid fuel motor while the fourth-stage is a liquid stage using Monomethyl-Hydrazine and Dinitrogen Tetroxide/Nitrogen Dioxide as fuel.

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The Science of GSLV

Geosynchronous Satellite Launch Booster

The glorious journey began at the magnanimous

St.Mary Magdalene Church (left),

it was the first lab and office of ISRO 

Currently maintained as a majestic Space Museum - Image: ISROHQ

THE EVOLUTION OF INDIA’S ROCKET PROGRAM

In 1962 in a rather nondescript fishing hamlet called Thumba near Thiruvananathapuram close to the sea, two stalwarts and visionaries of the Indian Space and Nuclear program were scouting for a new rocket launching facility along with other fellow scientists. One was the blue-blooded Dr. Vikram Sarabhai and the other the aristocratic Dr. Homi Jehangir Bhabha. Within a year’s time the Thumba Equatorial Rocket Launching Station (TERLS) was born. This was just a humble beginning but over the years, India achieved the capability of building its own launch vehicles, remote sensing, communication, defense and navigation satellites, launch interplanetary and lunar missions, design and develop the closely guarded and cutting-edge cryogenic engine. TERLS primarily focused on launching sounding rockets (SR) to study of equatorial electro-jet phenomena, which is a stream of electric current flowing in a narrow band on either side of the magnetic equator at a height of around 100 kms.

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