[Note 1: Motor cases of a solid-propellant rocket serve as "a container for solid- propellant fuel" and "a vented pressure chamber in which the fuel is burned to provide forward thrust when expanded into the exit cone of the nozzle." The most commonly used materials used to build motor cases are ferrous alloys, including conventional "quench and temper" (hardened by heating and then plunging into liquid to cool quickly) steels and nickel precipitation-hardening alloy steels (e.g., maraging steel), nonferrous titanium alloys, aluminum alloys, and fiberglass reinforced plastics.
Note 2: The nozzle is the "device by which the internal energy of the exhaust gases is converted into kinetic energy, thereby producing thrust. For any given propellant system, the nozzle acts as a metering device to control the rate of gas flow, thus creating a predictable amount of thrust over a programmed time period. The energy conversion is accomplished by causing the gas molecules to accelerate to extremely high velocities as they leave the motor." The materials used in the fabrication of nozzles include structural materials (aluminum alloys and fiberglass- resin composites), adhesives, sealants and greases (zinc chromate, silicone grease), thermal insulators (composites of asbestos fibers and phenolic resins), coatings of refractory materials (e.g., zirconium dioxide), and ablative materials.
Note 3: A fin is an "aerodynamic appendage fixed to the body of a launch vehicle, typically at the base of the first stage, which provides stability during flight."
Note 4: The term "nose cone" refers to the "forward end of the rocket; the section which generally contains the payload."
Note 5: Explosive forming in metallurgy refers to "the use of explosives for controlled sheet metal forming." Although there are references to the process in the late 19th century, explosive forming developed in the United States during the 1950s with the growth of the aerospace industry. In explosive fabrication, "an explosive charge is detonated in the vicinity of the workpiece, as a result of which the metal is given very rapid acceleration over a very short period of time and is formed into a die shape, mainly as a result of its own kinetic energy. This process is normally used for the forming of a flat sheet or plate into a form die." Explosive forming is used for "performing operations on very large parts [of metal] where the forces required are beyond the capacity of most conventional presses...for forming sheet metal parts in different materials and to new shapes, and...to produce savings in the production of short-run items and prototype parts."]
—Department of Space (Government of India), Annual Report: 1973-74, pp. 12-15; Thiokol Propulsion, "Cases," Rocket Basics: A Guide to Solid Propellant Rocketry, <http://www.thiokol.com/>, pp. 14-16; Thiokol Propulsion, "Nozzles," Rocket Basics: A Guide to Solid Propellant Rocketry, <http://www.thiokol.com/>, pp. 20-24; Mark Williamson, Dictionary of Space Technology (New York: Adam Hilger, 1989), pp. 121, 224; R. Davies and E.R. Austin, "Sheet Metal Forming: Explosive Forming," Developments in High Speed Metal Forming (New York: Industrial Press Inc., 1970), p. 184.

1973
According to the Department of Space (DOS) Annual Report, the Vikram Sarabhai Space Centre (VSSC) is seeking design competence and pilot production of devices needed for:

• Instrumentation to evaluate the performance of propellants and rocket motors during static flight-tests;
• In-flight stabilization and control of rockets and satellites, and;
• Control and guidance of multistage vehicles designed for orbiting satellites.

To achieve these goals, VSSC has developed a series of transducers to measure parameters such as thrust, acceleration, and pressure over a large range. Voltage and charge amplifiers to process the signals of these transducers and voltage-controlled oscillators to telemeter the measurements have also been developed. These instruments have been used in static and flight-tests of Menaka-I, Menaka-II, RH-125, RH-300, and RH-560 rocket motors and their propellants. VSSC has also standardized the design of inertial sensors such as "rate gyroscopes," "free gyroscopes," and "high-precision accelerometers." The inertial system under development will be used for "attitude reference" as well for the inertial measurement system of the SLV-3. A prototype system for "RH-300 roll-control, flight by fin-tip control" is under fabrication and an "electro-hydraulic fin- tip control system" for the RH-560 sounding rocket will be ready soon. Successful experiments have also been conducted with "strontium perchlorate as a secondary injectant for thrust vector control of rockets." An on-board digital computer has been designed for the control and guidance system of the SLV-3. The modular design of the computer permits its use with both the "stabilized-platform type" and "strapped-down type of inertial measurement systems." The ground model of this computer is nearing completion and preliminary experiments have been conducted to fabricate the computer using micro-electronic packaging techniques.
VSSC's Electronics Development Division has also developed the first phase of a PCM ground data recovery system. The division will supply a telemetry system to the SHAR, Sriharikota (Andhra Pradesh), which will have facilities to receive PCM and FM data from rockets and satellites. [Note 1: A transducer is an electronic device that converts energy from one form into another; in a rocket, it produces an electrical signal proportional to a force or pressure input. Note 2: An oscillator is an electronic device used for the purpose of generating a signal. Oscillators are found in computers, wireless receivers and transmitters, and audio frequency equipment. An oscillator employs a sensitive amplifier whose output is feedback to the input in phase. Thus the signal regenerates and sustains itself. Note 3: Thrust vector controls (TVC) are used to achieve directional or attitude correction in solid rockets by vectoring or deflecting the thrust of the rocket motors. The two primary methods of producing lateral thrust with fixed nozzles include mechanical interference (MITVC) and secondary injection thrust vector control (SITVC). MITVC involves changing the direction of the supersonic gases at the nozzle exit plane by inserting a heat resistant body into the exhaust stream to deflect it. Devices used in this method include jet vanes, jetavators, and jet tabs. SITVC is accomplished by injecting fluid (liquid or gas) into the main exhaust stream of the rocket motor through ports in the expansion section of the nozzle. The motor's thrust is deflected by the force of the injected fluid and by the imbalance of pressure created in the nozzle.]
—Department of Space, Government of India, Annual Report: 1973-1974, pp. 16-17; Whatis.?Com, <http://whatis.techtarget.com/>; "Category II-Item 9: Navigation," Missile Technology Control Regime Annex Handbook, pp. 9-4, 9-7-9-8; Thiokol Propulsion, "Flight Direction Control," Rocket Basics: A Guide to Solid Propellant Rocketry, <http://www.thiokol.com/>, pp. 25-28.

1973
Four fiber-glass motor cases for the fourth-stage of the SLV-3 are built by the Reinforced Plastics Centre (REPLACE) and pressure-tested. Qualification tests are planned to be completed by the end of 1974.
—Department of Space (Government of India), Annual Report: 1973-1974, p. 19.

January 1973
First meeting of the ISRO-CNES joint commission (the Indian Space Research Organization and French space agency).
—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 122.

May 1973
The Indian Space Research Organization (ISRO) develops a 600kg-thrust liquid-fuel engine; the engine is based on a storable bi-propellant system using red-fuming nitric acid (RFNA) and aniline. Sufficient progress is made to build a flightworthy rocket stage based on liquid propulsion.
—Department of Space (Government of India), Annual Report: 1973-74, p. 18.

May 1973
Intra-organizational differences in the Defense Research & Development Laboratory (DRDL) hamper progress on the Valiant ballistic missile program. The leader of the Valiant team, S.L. Bansal, believes that the lab director V.S. Narayanan is far too focused on the Devil program.
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), p. 172.

May 1973
First launch of a liquid-fuel rocket from The Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh). A 3.5-ton-thrust "clustered solid grain booster" is used for the rocket.
—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 111-112; Department of Space (Government of India), Annual Report: 1973-74, p. 18.

June 1973
Due to intra-organizational differences, S.L. Bansal is removed from the Valiant program and appointed director of missiles at the Defense Research & Development Organization (DRDO) office in New Delhi.
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), p. 172.

Late 1973
The Indian Space Research Organization (ISRO) begins work on the design of various components, subsystems, and systems for the SLV-3.
—R. Nagappa, M.R. Kurup, and A.E. Muthunayagam, "ISRO's Solid Rocket Motors," Acta Astronautica, vol. 19, no. 8, 1989, p. 683.

December 1973
A French team from its space agency CNES tours Indian industrial establishments.
—Department of Space (Government of India), Annual Report: 1973-1974, p. 44.

1974
Due to faltering progress and insufficient interest in the Valiant program, the union cabinet requests that Dr. Nagchaudhuri explores whether the liquid-fuel engine developed for the Valiant can be used by the Indian Space Research Organization (ISRO) for the civilian satellite launch vehicle. During a meeting of the Defence Research & Development Laboratory (DRDL) and ISRO officials at the IISc in Bangalore (Karnataka), ISRO rejects the liquid-fuel engine, citing its own efforts in developing solid motors. The IISc's aeronautical department also appraises DRDL's efforts critically and cites instability problems in the Valiant's liquid-fuel engine. The Valiant program is subsequently terminated.
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), p. 173.

1974
The Indian Air Force loses interest in the Devil program (reverse engineering of the Soviet SA-2 missile) and regards it as "technology gathering" project. The Air Force's waning interest is partly the consequence of the poor performance of the SA-2 in the 1971 Bangladesh War. An internal Air Force investigative committee concludes that of the 11 missiles fired during the war, almost all were directed towards the wrong target; the rest missed their targets completely. The Air Force's skepticism with the program is also linked to the Defense Research & Development Organization's (DRDO) failure to develop a powerful gas-turbine engine for the HF-24 Marut combat aircraft. The Air Force lobbies the government to purchase the solid-fuel Pechora surface-to-air missile (SAM), which is on offer from the Soviet Union. [Note: Development of the Pechora (SA-3) SAM began in 1956 at the Lavochkin OKB design bureau. The Pechora was designed to complement the SA-2 at low and medium altitudes; the first battery became operational in 1961. The Pechora is a two-stage weapon with a large solid-propellant booster and a smaller solid-fuel sustainer rocket motor. The booster is fitted with four large rectangular stabilizing fins. The main body is cylindrical in shape with four clipped delta shaped fins aft of the mid-point and four small delta moving control fins on the nose taper and four rectangular fins on the rear. The overall length of the missile is 6.1m, the diameter of the booster stage is 0.55m and that of the missile proper is 0.37m.]
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), pp. 167-168; "SA-3 'Goa' Low to Medium Altitude Surface-to air Missile System, Tony Cullen and Christopher Foss, eds., Jane's Land Based Air Defence 1992-93 (Coulsdon, Surrey), pp. 261-262.

1974
India signs an agreement with France to supply transducers for the French Ariane program. The Vikram Sarabhai Space Centre's (VSSC) Pressure Transducer Unit (PTU) is expected to begin production by September 1975.
—Department of Space (Government of India), Annual Report: 1974-1975, p. 18.

1974
The Indian Space Research Organization's (ISRO) Propellant Fuel Complex (PFC) in Thiruvanathapuram (Kerela) becomes operational. Trial runs for the production of HEF-20 polyester VI-1, polyester PR-6, phenol formaldehyde resin, dicotyl adipate, perbenzoic acid, and polyurethane resin are successful. Special polysters, formaldehydes, polyurethane resins, and other chemicals are produced in the complex in sample and production quantities for utilization in various rocket development programs.
—Department of Space (Government of India), Annual Report: 1974-1975, p. 12; Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 90.

1974
The Indian Space Research Organization (ISRO) develops ISROPolyol as a substitute for the imported hydroxyl-terminated polybutadiene (HTPB). It also develops carboxyl-terminated polybutadiene (CTPB) for the third and fourth stages of the SLV-3. In addition, 10 chemical resins and adhesives are synthesized for various other "national agencies" under an import substitution program. [Note: HTPB is a binder and fuel used in solid-rocket motor propellant.]
—Department of Space (Government of India), Annual Report: 1974-1975, p. 12; "Category II-Item 4: Propellants," Missile Technology Control Regime Annex Handbook, p. 4-11.

1974
In the field of aerospace materials technology, Indian space and defense agencies:

• Experiment with different grades of maraging steel on a laboratory scale. The Indian Space Research Organization (ISRO) collaborates with the Bhabha Atomic Research Center (BARC) and Defense Metallurgical Research Laboratory (DMRL) to develop titanium alloys. Evaluation trials are conducted on tungsten-molybdenum materials with applications in rocket motor thrust-vector control systems.
• Develop asbestos-phenolic composites for rocket nozzles. The Vikram Sarabhai Space Centre's (VSSC) fibre reinforced plastics division develops molded scaled-down heat-shields for the SLV-3. The VSSC also develops fiber-glass sounding rocket chambers, including 650mm-diameter SLV-3 stage-four motor cases. Phenolic-heat resistant materials for nozzles are successfully tested for the fourth-stage.

[Note 1: Maraging steels are steel alloys with strengths up to approximately 300,000psi in combination with a high fracture toughness. The term "maraging" is derived from the fact that these alloys exist as relative soft, low-carbon martensites (a solid solution of iron and up to one percent of carbon, the chief constituent of hardened carbon tool steels) in the annealed condition and gain high- strength from aging at relatively low temperatures. Maraging steel alloys were originally developed by International Nickel Company in 1959. Designation of each alloy refers to the nickel (Ni) content; for example, the four main grades are 25% Ni maraging steel; 20% Ni maraging steel; 18% Ni maraging steel; and 12% Ni maraging steel. The 18% Ni maraging steel is the most versatile and most widely used. Strength can be controlled by the aging treatments and hardener content (titanium, cobalt, molybdenum, and aluminum). Maraging steel is machined easily, has excellent weldability, and fracture toughness. The 18% Ni maraging steel heat treats at low temperatures, which is important in manufacturing very-large diameter motor cases. Note 2: Tungsten, molybdenum, and alloys of these metals can be formed into missile parts by pouring them into a mold and subjecting them to high heat and pressure. Parts made from these materials are very hard, dense, and strong. They also have extremely high melting temperatures. Thus, finished parts are resistant to ablation in a high-heat and mass-flow environment such as those experienced in re- entry or in missile exhausts. These metals are used to manufacture re-entry vehicle nosetips, nozzle throat inserts, and jet vanes, which are used to steer engine exhaust.]
—Department of Space (Government of India), Annual Report: 1974-1975, p. 13; George P. Sutton, "Components of Solid Rockets," Rocket Propulsion Elements: An Introduction to the Engineering of Rockets (New York: John Wiley & Sons, 1986), pp. 326-327; "Category II-Item 8: Structural Materials," Missile Technology Control Regime Annex Handbook, pp. 8-7.

1974
The Indian Space Research Organization's (ISRO) successes in rocket hardware development and fabrication include:

• Consolidation of all sounding rocket activities under the Rohini Sounding Rocket (RSR) program. Special sounding rocket launches for qualification of the SLV-3 project.
• Completion of feasibility study to boost the range and payload of the two-stage RH-300 rocket using aluminized polyvinyl chloride (PVC) and RCN propellants for the booster and high-energy propellant (PP-10) for the Centaur sustainer. This combination will enable a boosted RH-300 to reach altitudes of 150-200km.
• Two flight-tests of the RH-560 rocket using strip-wound motor chambers.
• Completion of structural qualification tests on the SLV-3 stage-four motors.
• Development of SLV-3 sub-systems.
• Design and development of composite nozzles for SLV-3 stages.
• Progress in the development of a 3-ton-thrust bipropellant liquid-fuel engine. ISRO proposes to eventually upgrade the engine so that it can meet the requirements of the SLV-3 as a strap-on booster or as an upper stage.
• Tests of a three-quarter size second-stage motor for the SLV-3.
• Completion of system development and component fabrication of a Secondary Injection Thrust Vector Control (SITVC) system using strontium perchlorate.

—Department of Space (Government of India), Annual Report: 1974-1975, pp. 13, 17.

1974
During 1974, the Indian Space Research Organization (ISRO) launches a total of 102 rockets from the Thumba Equatorial Rocket Launching Station (TERLS). Here is the breakdown of these launches:

—Department of Space (Government of India), Annual Report: 1974-1975, p. 19.

1974
The Department of Space (DOS) annual report states that the Indian Space Research Organization (ISRO) has tested two operational models of the "miniature rate gyroscope." In addition, an operational model of the "free gyroscope" has been ground-tested while the first prototype of a "single-degree-of-freedom Rate Integrating Gyroscope (RIG)" is nearing completion. A "single-axis inertial-stabilizing platform" is being assembled and it will provide data and experience for developing "3-axis 4-gimballed inertial platforms required for SLV-3 missions." ISRO has also succeeded in assembling "the ground model of the onboard processor for SLV-3 (a 21- bit system using 4K word memory with 5 microsec cycle time)." In addition, the "system of the fin-tip control system for the flight control of the first-stage of the SLV-3 has been completed and the components such as servo-valves and actuators are under development." The report also notes, "transducers based on strain gauges and piezo-electric quartz cells are under pilot production...light-weight vibration pick-ups, universal thrust pick-ups, and semiconductor type pressure pick-ups have been developed."
—Department of Space, Government of India, Annual Report: 1974-1975, p. 14.

1974
Work begins on the installation of a special environmental test facility for satellites at the Vikram Sarabhai Space Centre (VSSC). The 1.25m-diameter thermovacuum chamber will be able to achieve a temperature range from -60°C to +120°C. Work is also in progress on a kinetic heating simulator for tests under combined environments of thermal and static loads as well as ejection tests. The climatic chambers are expected to be commissioned by March 1975.
—Department of Space (Government of India), Annual Report: 1974-1975, p. 19.

1974
Work continues on facilities at the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh). During 1974, the Indian Space Research Organization (ISRO):

• Completes a sounding rocket complex for flight-testing single- or two-stage sounding rockets up to a maximum diameter and weight of 560mm and 1.5-tons, respectively.
• Undertakes a project to expand the sounding rocket launch facility to include the launch of multi-stage combinations of RH-650 and RH-800 rockets.
• Makes progress in the construction of the SLV-3 launch complex.
• Continues development of ground support facilities such as telemetry systems, tracking and telecommand systems, computer and data processing facilities, rocket sled facility, and the static-test evaluation complex.

—Department of Space (Government of India), Annual Report: 1974-1975, pp. 20-25.

1974
The Indian Space Research Organization (ISRO) commissions a 6,000-ampere modular industrial electrolytic cell with a capacity to manufacture 10 tons of ammonium perchlorate (AP) annually.
—Department of Space (Government of India), Annual Report: 1974-1975, p. 12.

1974
The Department of Space (DOS) annual report states that a "substantial number of ISRO [Indian Space Research Organization] engineers and scientists have received training in France." Similarly, the training of ISRO personnel at the West German space agency DFVLR, which began in July 1973, continued in 1974. There have been two types of trainees. A group of 10 trainees (90 man- months) have been trained at the high-altitude test facilities at Lampoldshausan. Another group of 13 trainees (103 man-months) have received training in different fields including remote sensing techniques, microwaves, pulse code modulation (PCM) telemetry, and wind tunnel testing. Details for training programs in 1975 are being planned.
—Department of Space (Government of India), Annual Report: 1974-1975, p. 42.

1974
The Defence Research & Development Laboratory's (DRDL) budget increases nearly 40 fold, from 4 million rupees in 1972 to 160 million rupees in 1974.
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), p. 166.

April 1974
First test of a two-stage RH-560 sounding rocket. The RH-560 uses an aluminized polyvinyl chloride (PVC) propellant; the RH-560 is modeled on the French Dragon sounding rocket and carries an 86kg payload to a height of 280km. [Note 1: The Dragon sounding rocket is a two-stage vehicle. It uses a 560mm booster in the first stage to boost the Belier upper stage. The Dragon first flew in 1962 and can carry a 60kg payload to a height of 475km. The Indian Space Research Organization (ISRO) later used the RH-560 as a platform to test the SLV-3's guidance and control system. Note 2: Metals such as aluminum, beryllium, boron, magnesium, and zirconium are added to the solid-propellant grain or to liquid fuel to enhance propellant performance. For example, aluminum powder as a fuel additive makes up 5 to 21% by weight of solid propellant. Combustion of the aluminum fuel increases the propellant flame temperature by 526.85°C and increases specific impulse by as much as 10%.]
—Gopal Raj, "First Steps in Rocketry," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 41-43; Jonathan McDowell, "CNES Sounding Rockets," History of Spaceflight, 26 January 2000, <http://hea-www.harvard.edu/QEDT/jcm/space/book/index.html>; "Category II-Item 4: Propellants," Missile Technology Control Regime Annex Handbook, p. 4-4.

10 May 1974
The Defence Research & Development Laboratory (DRDL) conducts its first test of a liquid-fuel engine developed for the Valiant ballistic missile; the engine is tested for five seconds.
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), p. 174.

18 May 1974
The Indian government announces that it has conducted a successful test of a 10-15kt nuclear device at the Pokhran test site in Rajasthan.
—"The New York Times Company: Abstracts," 19 May 1974; in Lexis-Nexis Academic Universe, <http://web.lexis-nexis.com>.

13 June 1974
Beginning of the flight qualification program for SLV sub-systems. A Centaur rocket is launched from TERLS carrying miniature rate-gyros, vehicle attitude programs, tone range receiver, and a scaled-down fiber-glass heat shield; the test is successful.
—Department of Space (Government of India), Annual Report: 1974-1975, p. 11.

July 1974
The Aeronautical Development Establishment (ADE) in Bangalore (Karnataka) tests an air-launched supersonic expendable drone in an attempt to develop an unmanned aerial vehicle (UAV). The project is named "Missile Target" and is released over a test-range to simulate an aerial threat to train gun and missile crews. The vehicle is auto stabilized and uses a canard configuration. [Note: Unmanned aerial vehicles (UAV) are "typically air-breathing vehicles which use aerodynamic lift to fly and thereby perform their entire mission within the earth's atmosphere. The most common mission for UAVs is reconnaissance. They are usually powered by small turbine or piston engines that drive either free or ducted propellers. UAVs tend to fly at relatively slow speeds of 360 to 540km/hr, usually for several hours....UAVs...can fly at altitudes ranging from very low, nap-of-the-earth trajectories to very high altitudes...UAVs are launched from many platforms, typically trucks, aircraft, and ships. They may fly autonomous preplanned routes and/or routes controlled by a human operator. After their mission is completed, they usually return to base to be used again.... UAVs are most typically used as reconnaissance platforms and thus carry electronic, video, or photographic payloads to gather or monitor data over unfriendly territory. They are designed to optimize time on station, which, for some systems, can be more than 24 hours. Because of their long-range, flexible payload, ease of acquisition, and reasonable cost, UAVs are potential delivery vehicles for weapons." It should also be noted that UAVs powered by piston or reciprocating engines fly at speeds substantially less (~150km/hr) than turbine-powered systems.]
—J. Jayaraman, "Technological Advances and Cost Effectiveness of Unmanned Air Vehicle Systems," in H.S. Mukunda and A.V. Krishnamurty, eds., Recent Advances in Aerospace Sciences and Engineering: Volume II (Bangalore: Interline Publishing, 1992), p. 165; "Complete Rocket and UAV Systems: Category I-Item 1," Missile Technology Control Regime Annex Handbook, pp. 1-5-1-6.

July 1974
Second meeting of the ISRO-CNES joint commission (the Indian Space Research Organization and French space agency). The two working groups meet to discuss satellite launch vehicles (SLVs) and communication satellites.
—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 122; Department of Space (Government of India), Annual Report: 1973-1974, p. 44.

July-December 1974
The Indian Space Research Organization (ISRO) and French space agency CNES sign an agreement to allow India to acquire French Viking liquid-fuel engine technology. Under the agreement, Indian engineers will work alongside specialists from the French firm SEP and provide hundreds of man-years of effort towards developing the Viking engines needed for the Ariane rocket. In return, Indian engineers will acquire the capability to build Viking engines in India. [Note: As a result of this agreement, within five years, India acquired the technology to build high-thrust, turbopump-based liquid-propellant engines. ISRO not only acquired the drawings and technical documentation for the engine, but since Indian engineers worked in tandem with their French counterparts, it also acquired critical know-how for the design principles for such engines. ISRO sent approximately 50 engineers to work on the Viking program in France. Under the contract Indian engineers were supposed to provide 75 man-years to SEP; the remaining 25 man-years could be used by ISRO to develop competence in areas of its choice. By the end of 1980-81, Indian engineers contributed nearly 135 man-years of work. Although ISRO budgeted 27 million rupees for the Viking program in 1974, total costs had escalated to 40 million rupees by 1980-81.]
—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 122-124.

1974-1975
The Department of Space (DOS) annual report says that the three-ton thrust, liquid-fuel engine currently under development "for a test vehicle, will eventually be upgraded to meet the requirements of SLV-3 as a strap-on booster and as an upper stage." The three-ton thrust engine has five times as many injector elements as the 600kg-thrust engine. The asbestos-phenolic ablative lining first tried out in the 200kg- and 600kg-thrust engines is retained in the early trials of the three-ton thrust engine. It is later replaced by an improved ablative lining made up of silica fibers embedded in phenolic resin. Graphite is used to line the throat of the nozzle. The erosion of graphite by hot gases allows the engine to be fired for about 45 seconds. [Note: Ablative materials are used to withstand a combination of erosion, fusion, corrosion, or decomposition, leading to progressive degradation, and or loss of material as a direct consequence of exposure to hot propellant gas flow in the nozzle.]
—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 112; Thiokol Propulsion, "Nozzles," Rocket Basics: A Guide to Solid-Propellant Rocketry, <http://www.thiokol.com/>, p. 23.

Mid-1970s
The Defense Research & Development Laboratory (DRDL) sets up a facility for manufacturing fiber-reinforced plastics for the Valiant's re-entry vehicle and imports a filament-winding machine from the United States for this purpose. [Note: Filament winding machines lay strong fibers coated with an epoxy or polyester resin onto rotating mandrels in prescribed patterns to create high strength-to-weight composite parts. The machines can be programmed in three or more axes for the purposes of positioning, wrapping, and winding fibers. Filament winding machines are typically used to make rocket motor cases, propellant tanks, and payload shrouds. The high-strength and low-weight of the resulting structures make increased missile ranges and payload rates possible.]
—Raj Chengappa, "The Devil's Workshop," Weapons of Peace: The Secret Story of India's Quest to be a Nuclear Power (New Delhi: Harper Collins Publishers India, 2000), p. 171; "Category II-Item 6: Composite Production," Missile Technology Control Regime Annex Handbook, pp. 6-1-6-2.

Mid-1970s
The private sector match manufacturer Wimco begins supplying ammonium perchlorate (AP) to the Indian Space Research Organization (ISRO).
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 97.

1975
In the field of solid and liquid propellants, the Indian Space Research Organization (ISRO):

• Flight-qualifies the newly developed PP-10 propellant for the RH-300 program.
• Casts the fourth stage motor of the SLV-3 using HEF-20 as a substitute for imported carboxyl-terminated polybutadiene (CTPB); the Vikram Sarabhai Space Centre (VSSC) in Thiruvanathapuram (Kerela) launches program to begin scaled-up production of HEF-20-based propellant and PP-10 propellant.
• Develops pyrotechnic devices including ignition and separation systems using Rohini rockets for the SLV-3 program.
• Sets up additional facilities for the development of polybutadiene-acrylic acid-acrilonitrile (PBAN) and a pilot plant for the production of poly-isobutylene.
• Finalizes engineering details for building an ammonium perchlorate (AP) plant in Alwaye (Kerela).
• Casts the three segments (each weighing 2.9 tons) of the SLV-3 first-stage proof motor and a 3.2-ton single-grain cast for the second-stage proof-motor. The first-stage motor (1m in diameter and 9m long) is successfully static-tested at the Static Test & Evaluation Complex (STEX) facility in SHAR, Sriharikota (Andhra Pradesh).
• Begins synthesis of methyl aziridinyl phosphine oxide and triepoxides which are used as curatives for CTPB/PBAN propellants
• Commissions key facilities at the Solid Propellant Space Booster Plant (SPROB) such as the propellant mixing stations, oxidizer grinding and blending stations; other facilities including those for casting, curing, and non-destructive testing are in the final stages of completion. The entire plant itself is expected to be commissioned within a few months.

[Note: ISRO adopted the segmentation route in casting the SLV-3 first-stage motors because, until the commissioning of SPROB in 1976, it did not have a facility to cast large monolith solid motors.]
—Department of Space (Government of India), Annual Report: 1975-1976, pp. 13-14; Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Program (New Delhi: Viking by Penguin Books India, 2000), pp. 78-79.

1975
Captive tests of a flight-vehicle employing a three-ton-thrust, liquid-propellant engine using red-fuming nitric acid (RFNA) and aniline near completion. Research and development continues on gas generators, turbopump feed systems, flow-control systems, and thrust chambers for meeting the needs of future programs. Indian engineers and scientists also acquire technology and training related to high-thrust liquid engines through the Vikas project with France.
—Department of Space (Government of India), Annual Report: 1975-1976, p. 3, 20.

1975
Significant developments in aerospace-related materials technology include:

• Finalization of heat-treatment cycles for 15CDV6, techniques for the melting, casting, and rolling of maraging steel, and welding techniques for titanium alloy gas bottles.
• Testing of indigenously developed carbon fibers for ablative applications.
• Development of tungsten-based materials for jet vane applications.
• Development of nozzle throat inserts based on tungsten and molybdenum.
• Developments of catalysts for applications in control rockets and provide multi-start capability.
• Fabrication of two full-sized heat shields for the SLV-3.
• Commissioning of a polar [filament] winding machine (PH-500), and a helical [filament] winding machine (H-1000) for winding pressure bottles and rocket motor cases, respectively. Design of a vertical nozzle winding machine (1,500mm diameter capacity) and a racetrack type filament-winding machine.

[Note: Gas bottles are used to store high-pressure gas. The high-pressure gas can be used to pressurize liquid-fuel tanks or to provide energy and means to move actuators and valves in both solid- and liquid-fuel rockets. Additionally pressure bottles are found in propellant storage tanks for attitude control thrusters.]
—Department of Space (Government of India), Annual Report: 1975-1976, p. 14.

1975
As part of the rocket development project, the Indian Space Research Organization (ISRO):

• Tests an RH-300 with the newly developed PP-10 propellant.
• Undertakes design of a stretched RH-560 single-stage rocket.
• Introduces design improvements in the Menaka-I (Mark I) and Menaka-II (Mark II) rockets.
• Completes project to indigenize the Centaur rocket production in India. The Centaur rocket is also used to flight-test the worthiness of SLV-3 sub-systems.

—Department of Space (Government of India), Annual Report: 1975-1976, pp. 18-19.

1975
The establishment of the Rocket Propellant Plant (RPP) at the Vikram Sarabhai Space Centre (VSSC) in Thiruvanathapuram (Kerela) nears completion.
—Department of Space (Government of India), Annual Report: 1975-1976, p. 15.

1975
According to Department of Space (DOS), the Indian Space Research Organization (ISRO) is making plans to develop launch vehicles that will be capable of placing communication satellites in a geostationary orbit. Studies are being conducted for estimating the "orbital capabilities of stage combinations of such a vehicle."
—Department of Space (Government of India), Annual Report: 1975-1976, p. 20.

1975
India sets up a unit to manufacture and supply high-accuracy pressure transducers for the European Ariane launch vehicle project. The Pressure Transducer Unit (PTU) is located on the campus of the National Aeronautical Laboratory in Bangalore (Karnataka); the first batch of 70 21U transducers are fabricated and exported to France. Plans are made to expand production to include 21UR and 21NS transducers.
—Department of Space (Government of India), Annual Report: 1975-1976, p. 20; Department of Space (Government of India), Annual Report: 1978-1979, p. 21.

1975
Special environmental test facilities are installed at the Vikram Sarabhai Space Centre (VSSC) in Thiruvanathapuram (Kerela) to simulate conditions in space for satellites and test the upper stages and heat-shields of the SLV-3. The facilities include the commissioning of a 1.25m thermovacuum chamber, and the installation of a kinetic heat simulator to test SLV-3 heat shields. Ground environmental facilities such as thermal cycling chamber and humidity chamber are commissioned and used to test the fourth-stage motor cases of the SLV-3.
—Department of Space (Government of India), Annual Report: 1975-1976, p. 23.

1975
The Indian Space Research Organization (ISRO) expands the sounding rocket complex at the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh) to flight-test the second and fourth stages of the SLV-3 and for qualifying its sub-systems. Construction begins on a satellite launch vehicle complex 4km south of the sounding rocket complex for the SLV-3. The facility will provide "complete support for vehicle assembly, check-out, and launching operations." It will consist of facilities such as "launch pad, block house, vehicle integration building, service building, pyrotesting building, and terminal building." The Department of Space (DOS) annual report states that progress has also been made in building telemetry, tracking, telecommand, range timing, radio communications, and computer & data processing facilities for tracking satellites and rockets at SHAR.
—Department of Space (Government of India), Annual Report: 1975-1976, pp. 26-27.

1975
During 1975, the following facilities are commissioned at the Static Test & Evaluation Complex (STEX) at the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh):

• Parts processing facility;
• Trimming and conditioning facility;
• Motor storage facility;
• Facilities for material handling; and
• Load cell calibrator.

[Note: The Department of Space (DOS) annual report notes that, "construction work on four numbers of single- component test stands to test different stages of SLV-3 and the test bay No.1 consisting of 25-ton and 100-ton thrust capacity test beds to accommodate the test stands has been completed and commissioned. These will meet the complete requirement of single component measurement programs for SLV-3. The fabrication work on two numbers of six-component test stands, with high and low capacities to test the motors and thrust vector control system of the first-stage of the SLV-3 and RH-560 has been completed. The construction work on the Spin Test Facility for testing the fourth-stage of the SLV-3...is nearing completion. To accommodate the six-component test stands and spin test stands, the test bay No. 2 consisting of 25-ton and 100-ton thrust capacity test beds has been constructed."]
—Department of Space (Government of India), Annual Report: 1975-1976, pp. 24-25.

1975
The Department of Space (DOS) reports significant advances in the development of telemetry and telecommand systems, tracking systems, and electronics production. A C-band radar with a tracking capability upto 2,500km is being installed at the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh); a C-band transponder to operate with this radar has also been developed. The Indian Space Research Organization (ISRO) has also undertaken the production of various on-board systems for rockets such as transmitters, regulators and mixers for the Rohini and SLV-3programs, and ground systems such as data amplifiers, time-code generators, and fire control panels.
—Department of Space (Government of India), Annual Report: 1975-1976, p. 18.

1975
Indian Space Research Organization (ISRO) scientists and engineers continue to receive training in French and West German research establishments.
—Department of Space (Government of India), Annual Report: 1975-1976, p. 45.

1 January 1975
The Scientific Advisor to the defense minister Dr. M.G.K. Menon appoints an independent review panel from Indian Space Research Organization (ISRO) under Dr. Brahm Prakash to conduct an external review of Project Devil. Committee members include A.P.J. Abdul Kalam, Dr. R.P. Shenoy, and Professor I.G. Sharma. The committee holds its first meeting on 1-2 January 1975.
—A.P.J. Abdul Kalam with Arun Tiwari, "Creation," Wings of Fire: An Autobiography (Hyderabad: Universities Press (India) Limited, 1999), p. 74.

February 1975
The Devil review panel holds its second meeting.
—A.P.J. Abdul Kalam with Arun Tiwari, "Creation," Wings of Fire: An Autobiography (Hyderabad: Universities Press (India) Limited, 1999), p. 74.

March 1975
After a third and final meeting, the Project Devil evaluation panel concludes that the Defense Research & Development Laboratory (DRDL) has made sufficient progress in hardware fabrication in the area of missile subsystems. The committee also finds that DRDL has accomplished the twin tasks of "hardware fabrication" and "systems analysis" in the design and development of ground electronics. However, more progress needs to be made in the area of liquid propulsion. The committee notes that the DRDL's philosophy of reverse engineering has taken precedence over the generation of design data. As a result, missile engineers have been unable to make much progress in overall systems analysis. The panel recommends that DRDL be allowed to proceed with Project Devil; the defense ministry accepts the panel's recommendations.
—A.P.J. Abdul Kalam with Arun Tiwari, "Creation," Wings of Fire: An Autobiography (Hyderabad: Universities Press (India) Limited, 1999), pp. 74-75.

April 1975-March 1976
The Indian Space Research Organization (ISRO) launches a total of 94 rockets between April 1975 and the end of March 1976. The break up includes:

—Department of Space (Government of India), Annual Report: 1975-1976, pp. 23-24.

1975-1976
Various sub-systems of the SLV-3 such as "stage motors, inter-stages, heat-shield, stage-separation systems, control and guidance systems, vehicle electronics, technology payload, and launch systems" progress from "design to development, fabrication and testing phases."
[Note: According to the Department of Space (DOS) annual report, the "stage proofmotor static test results indicate that the technology for propellants, insulation, igniter, and nozzle for all the stages have been developed."]
— Department of Space (Government of India), Annual Report: 1975-1976, pp. 19-20.

1976
The Indian Space Research Organization (ISRO) commissions plant (Reinforced Plastics Centre) to manufacture reinforced plastics.
—Department of Space (Government of India), Annual Report: 1978-79, p. 24.

1976
The Indian Space Research Organization's (ISRO) Precision Equipment Division (PED) in Thiruvanathapuram (Kerela) commissions facilities for manufacturing polybutadiene-acrylic acid-acrilonitrile (PBAN) binder used in solid-propellants.
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 91.

1976
The following facilities are commissioned at the Static Test & Evaluation Complex (STEX) at the Sriharikota High- Altitude Range (SHAR) in Sriharikota (Andhra Pradesh):

• Static acceleration test facility;
• Vibration test facility;
• Drop test facility; and
• Hot and cold chambers.

[Note: The STEX facility is completed in 1976 at a cost of 60 million rupees.]
—Department of Space (Government of India), Annual Report: 1975-1976, p. 24; Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 88.

October 1976
The Indian Space Research Organization's (ISRO) three-ton thrust, liquid-fuel engine is used to power the second stage of a sounding rocket, which uses an RH-560 as the first stage. The rocket is designed to fly to a height of 100km with a 175kg payload. However, a no-thrust phase between the burn out of the first stage and ignition of the second stage causes the test to fail. ISRO engineers introduce modifications in the rocket for further tests. In subsequent models, the first and second stages of the rocket are held together by metal struts and both stages are ignited on the ground to eliminate the no-thrust coast phase.
—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 112-113.

December 1976
A mid-term review of the SLV-3 program leads to the conclusion that the vehicle launch date will have to be postponed from 1978 to 1979. The postponement is caused by "delays in the delivery of stage motor and interstage hardware from outside fabricators (due to stringent quality requirements); unexpected deviations in performance of various subsystems after they had performed to satisfactions during earlier tests; and problems at system-level after integration of the subsystems."
—Gopal Raj, "SLV-3: India's First Launch Vehicle," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 68; Department of Space (Government of India), Annual Report: 1978-1979, p. 15.

1977
The Indian Space Research Organization's (ISRO) Precision Equipment Division (PED) uses its new resin binder, ISROPolyol, to cast a monolithic SLV-3 first stage.
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 92.

27 March 1977
The first-phase of the Solid Propellant Space Booster Plant (SPROB) is completed at a cost of 77.4 million rupees. Although most of the equipment for the plant is manufactured in India, critical facilities such as mixers to cast large solid- propellant motors and linear accelerators to X-ray finished propellant grains are imported. [Note: Indian scientists claim that only 15% of the high-tech equipment for the Rocket Propellant Plant (RPP) in Thumba (Kerela) and SPROB in Sriharikota (Andhra Pradesh) was imported; the bulk of the facilities to manufacture solid-propellants were conceived and developed by Indian Space Research Organization (ISRO) scientists and engineers.]
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 85-86; M.V. Kurup, V.N. Krishnamoorthy, and M.C. Uttam, "Development of Solid-Propellant Technology in India," Sadhana, vol. 12, part 3, March 1988, p. 233.

27 March 1977
Test of the first-stage monolithic SLV-3 motor; motor explodes during the test. As a result of the failure, the Indian Space Research Organization (ISRO) decides to proceed with the original plan for a segmented solid-propellant motor using polybutadiene-acrylic acid-acrilonitrile (PBAN)-binder resin.
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 92-93.

April-June 1977
Static test of satellite launch vehicle (SLV) third stage proof motor at the Static Test & Evaluation Complex (STEX). The SLV-3 heat shield and its jettisoning system are qualified in a series of tests simulating flight environments such as zero gravity, severe heat, and aerodynamic loading experienced during ascent of the vehicle in the atmosphere, vibration, and shock.
—Department of Space (Government of India), "Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-1979.

July-September 1977
Static test of the satellite launch vehicle (SLV) second-stage flight motor. The Indian Space Research Organization (ISRO) also successfully proves motor segmentation technology used to cast the first-stage motor.
—Department of Space (Government of India), "Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-1979.

August 1977
The Indian Space Research Organization (ISRO) commissions the satellite launch vehicle complex for the SLV-3 at the Sriharikota High-Altitude Range (SHAR).
—Department of Space (Government of India), Annual Report: 1975-1976, p. 26.

October-December 1977
First controlled flight of the RH-560 validates vehicle control philosophy and hardware design:

• Qualification of spin-up and separation systems for the SLV-3.
• Successful static-test of [segmented] first-stage flight motor.

—Department of Space (Government of India), "Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-1979.

1978
The Department of Space (DOS) commissions a 150-ton capacity ammonium perchlorate (AP) plant at Alwaye (Kerela). The plant is formally inaugurated in 1979. However, the plant is barely able to produce more than 40 tons of AP due to low demand from ISRO and an electrode process production bottleneck.
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 98-99.

1978
The gas generator system for the three-ton pressure-fed engine is qualified; down-rated tests on the three-ton turbopump systems coupled with the gas generator are completed:

• Hardware for long-burning three-ton engine for possible upper-stage applications is completed.
• The three-ton thrust liquid-fuel engine is tested as a single-stage rocket. However, "sloshing and vortex development," cause the engine to shut down prematurely.

—Gopal Raj, "Early Initiatives in Liquid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 113; Department of Space (Government of India), Annual Report: 1978-1979, p. 21.

1978
Indian Space Research Organization (ISRO) engineers continue participation in the program to develop the Vikas liquid- fuel engine with the French firm SEP. As part of the agreement with France, India receives most of the documents and drawings on systems description, specifications, fabrication, testing, and analysis related to the engine. [Note: As part of the contract with France, in part payment for the technology, high-quality pressure-transducers manufactured at the Pressure Transducer Unit (PTU) are exported to France. Over 4,000 transducers worth 9 million francs are delivered to France until the end of 1979.]
—Department of Space (Government of India), Annual Report: 1978-1979, p. 21.

1978
An insulated facility to measure electromagnetic interference on electronic packages nears completion. The Indian Space Research Organization (ISRO), Bhabha Atomic Research Center (BARC), and Indo-Burmah Petroleum also jointly undertake a project to design and develop a 4m thermovacuum chamber to provide larger environmental test facilities for spacecraft.
—Department of Space (Government of India), Annual Report: 1978-1979, pp. 24-25.

1978
The Indian Space Research Organization (ISRO) reports that facilities for the launch support and tracking of the satellite launch vehicle (SLV), which include the block house, launch pads, control center, vehicle telemetry, telecommand and tracking systems, data links, range timing, closed-circuit TV, inter-communication, computers, and range safety at the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh), are in an advanced stage of completion.
—Department of Space (Government of India), Annual Report: 1978-1979, pp. 26-27.

1978
Qualification of the proto model of a three-axis, four-gimbal inertial measurement unit (IMU).
—Department of Space (Government of India), Annual Report: 1978-1979, p. 22.

1978
Twenty satellite launch vehicle (SLV) stage motors are produced at the Solid Propellant Space Booster Plant (SPROB), the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh). A 100-liter sigma processor for processing propellant is commissioned at SPROB; another 1,000-liter mixer is installed at the Rocket Propellant Plant (RPP) in Thiruvanathapuram (Kerela).

• The non-destructive test facility at SPROB, with its 400KV x-ray facility, is used extensively for testing SLV stage-motors, liquid-engine nozzles, and igniters.
• RPP produces 51 tons of propellants. Process developments include modifications needed to avoid cracks in the SLV second-stage flight motor. A fluid jet-cutting facility is employed to recover motor-case hardware from defective propellant grains.
• The Propellant Fuel Complex (PFC) produces 24 tons of various resins, plasticizers, and chemicals needed for the SLV and Rohini Sounding Rocket (RSR) programs.
• A new plant is commissioned to augment polybutadiene-acrylic acid- acrilonitrile (PBAN) production to 7.5 tons per annum.

—Department of Space (Government of India), Annual Report: 1978-1979, pp. 22-23.

1978
The Indian Space Research Organization (ISRO) commissions a thermal humidity chamber at the Static Test & Evaluation Complex (STEX), the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh). Civil engineering and electrical works are also completed on a second high-altitude test (HAT) facility at SHAR. [Note: A thermal humidity chamber is used to perform climatic and accelerated ageing tests of upper-stage motors and sub-systems of launch vehicles.]
—Department of Space (Government of India), Annual Report: 1978-1979, p. 24.

January-March 1978
High-altitude tests on control rockets for SLV-3:

• Fabrication and assembly of SLV-3 mock-up model structure.
• Design review of problems encountered in satellite launch vehicle (SLV) second-stage nozzle.
• Award of contracts to HAL and other companies for the fabrication of SLV structural elements, assembly, and test fixtures.

—Department of Space (Government of India), "Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-1979.

April-June 1978
Erection of SLV-3 launcher completed:

• SLV-3 first-stage nozzle modified

—Department of Space (Government of India), "Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-1979.

July-September 1978
Integration of the Secondary Injection Thrust Vector Control (SITVC) system for the SLV-3 first stage complete:

• Qualification of inertial subsystems for the SLV-3
• Environmental qualification of SLV-3 fourth stage

—Department of Space (Government of India), "Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-1979.

October-December 1978
Successful static test of the satellite launch vehicle (SLV) first-stage flight motor with Secondary Injection Thrust Vector Control (SITVC):

• Qualification of the fin-tip control system
• Qualification of bipropellant motors for the second-stage reaction control system; Monopropellant thrusters for the SLV third stage are hot-tested
• Vibration and shock tests on SLV-3 heat-shield
• SLV-3 launcher load-test

—"Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-79, Department of Space (Government of India); Department of Space (Government of India), Annual Report 1978-1979, p. 17.

December 1978
Between 1976-78, the Indian Space Research Organization's (ISRO) reinforced plastics facility produces a total of six stage-three motor cases, 19 stage-four motor cases, 148 igniter cases and 12 gas bottles for the satellite launch vehicle (SLV) and Rohini Sounding Rocket (RSR) programs.
—Department of Space (Government of India), Annual Report: 1978-1979, p. 24.

1979
The union government accepts a proposal to build a National Testing Range (NTR) for testing rockets and missiles at Baliapal (Orissa) in principle.
—Paul Routledge, "The Baliapal Movement," Terrains of Resistance: Nonviolent Social Movements and the Contestation of Place in India (Westport: Praeger Publishers, 1993), p. 40.

1979
The United States bans the sale of polybutadiene-acrylic acid-acrilonitrile (PBAN) binders used in solid propellants to India.
—Gopal Raj, "Developing Competence in Solid Propulsion," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), pp. 90-91.

January 1979
The Balasore rocket launching station (Orissa) becomes operational with the launching of an RH-200 sounding rocket. [Note: India launched a total of 182 RH-200 sounding rockets in 1979 as part of the Monsoon Experiment (Monex).]
—Gopal Raj, "First Steps in Rocketry," Reach for the Stars: The Evolution of India's Rocket Programme (New Delhi: Viking by Penguin Books India, 2000), p. 42.

January 1979
Static test of the satellite launch vehicle (SLV) second-stage flight motor. With the conclusion of this test, all stage motors are qualified for flight. The Indian Space Research Organization (ISRO) also qualifies all the rocket interstages and begins preparations to begin assembling the launch vehicle.
—Department of Space (Government of India), Annual Report: 1978-1979, p. 16.

January-March 1979
The Indian Space Research Organization (ISRO) begins integration of the SLV-3 vehicle system.
—"Major Milestone Events During 1977-78 and 1979," Annual Report: 1978-79, Department of Space (Government of India).

15 February 1979
Indian Defense Minister Jagjivan Ram tells the parliament's consultative committee on defense that India has plans to equip its armed forces with the most sophisticated missiles. A missile committee appointed by the defense ministry has recommended that in addition procuring missiles from abroad, India should plan to develop and produce missiles indigenously.
—"Missiles For Armed Forces," New Delhi Home Service, 15 February 1979; in BBC Summary of World Broadcasts, Lexis-Nexis Academic Universe, 7 March 1979, <http://web.lexis-nexis.com>.

23 July 1979
According to the chairman of India's Space Commission, Professor Satish Dhawan, India has the capability to build intermediate-range ballistic missiles (IRBM), if the military requires them. However, the Indian Space Research Organization (ISRO) is developing rockets for peaceful purposes and is not collaborating with the defense department to build missiles. Dhawan says that, "we would have larger launchers if the military were giving a push." A rocket expert at the Vikram Sarabhai Space Centre (VSSC) in Thiruvanathapuram (Kerela) says that the fourth stage of the SLV-3 can theoretically be substituted by a warhead.
—"Ballistic Missile Capability," Press Trust of India (New Delhi), 23 July 1979; in BBC Summary of World Broadcasts, Lexis-Nexis Academic Universe, 15 August 1979, <http://www.lexis-nexis.com>.

10 August 1979
First experimental launch of the SLV-3 with the Rohini Technology Payload at 0228GMT from the Sriharikota High-Altitude Range (SHAR) in Sriharikota (Andhra Pradesh). The rocket fails to place the payload in orbit. An Indian Space Research Organization (ISRO) press release says that the flight was only partially successful following the abnormal behavior of the second stage of the four-stage vehicle. While the lift-off and separation of the booster stage was normal, the second stage showed abnormal change in flight attitude, preventing the payload from attaining full altitude and velocity. The flight terminated after five minutes and 15 seconds, and the first-stage motor and payload crashed into the Bay of Bengal, about 500km from Sriharikota (Andhra Pradesh). [Note: The SLV-3 is a four-stage solid-propellant vehicle, 22m tall, and having a lift-off weight of 16.9 tons. The vehicle's first stage of 1,000mm diameter is made up of 15CDV 6 steel and is loaded with 8,660kg polybutadiene-acrylic acid-acrilonitrile (PBAN) propellant. It's action time is 49 seconds and average thrust developed is 441 kN. The stage is controlled by secondary thrust vector and movable fin tips. The second-stage is 800mm in diameter. It is also built of 15CDV6 steel and 3,150kg of PBAN propellant. Action time is 39.9 seconds and average thrust developed is 196 kN. This stage is controlled by a bipropellant reaction control system. The third stage has a diameter of 815mm and is made of fiber-reinforced plastic. It has 1,060kg of HEF-20 propellant. The action time is 45 seconds and average thrust developed is 64 kN. This stage is controlled by monopropellant reaction control system. The fourth stage has a diameter of 657mm and is also made of fiber-reinforced plastic. It has 262kg HEF-20 propellant. The action time is 33 seconds and the average thrust developed is 21 kN. The fourth stage is "spin stabilized." All four stages are interconnected by aluminum alloy inter-stages housing instrumentation, control system, and separation system.]
—"Launch of SLV-3," New Delhi Home Service, 10 August 1979; in BBC Summary of World Broadcasts, Lexis-Nexis Academic Universe, 22 August 1979, <http://web.lexis-nexis.com>; R. Nagappa, M.R. Kurup, and A.E. Muthunayagam, "ISRO's Solid Rocket Motors," Acta Astronautica, vol. 19, no. 8, 1989, pp. 683-684.

11 August 1979
A post-flight review committee appointed to analyze the causes of the SLV-3 launch mishap concludes that launch failure occurred due to a failure in the second-stage control system. A "solenoid valve" in the oxidizer tank remained open after the first command at T-8 minutes, which resulted in the drainage of the red-fuming nitric acid (RFNA), used as the oxidizer. As a result, no control force was available during the second-stage flight, resulting in the vehicle became aerodynamically unstable, losing velocity and altitude. This finally caused the vehicle to plunge into the sea before the other stages could ignite.
—A.P.J. Abdul Kalam with Arun Tiwari, "Creation," Wings of Fire: An Autobiography (Hyderabad: Universities Press (India) Limited, 1999), pp. 95-96.

	Updated July 2003