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Beginning with the launch of modest Rohini Sounding Rockets for scientific investigations over the geomagnetic equator passing over Thumba near Thiruvananthapuram in 1960s, India has come a long way in designing, developing and operationalising two launch vehicle systems - Polar Satellite Launch Vehicle (PSLV) for launching mainly remote sensing satellites into polar orbits and Geosynchronous Satellite Launch Vehicle (GSLV) for launching communication satellites into Geosynchronous Transfer Orbit (GTO). A significant event during the year was the first successful operational flight of GSLV carrying India's exclusive satellite for education - EDUSAT.
Further progress has been made in the development of Cryogenic Upper Stage (CUS) to replace the Russian procured cryogenic stage on GSLV. The development of GSLV-Mk III has also made progress with the completion of the preliminary design review of all subsystems and the integrated technical reviews. Preparations for the next launch of PSLV have commenced. Airdrop test of Space Capsule Recovery Experiment (SRE) was successfully conducted at SDSC SHAR. Further research and development activities on air breathing propulsion have continued during the year. Geosynchronous Satellite Launch Vehicle (GSLV) The first operational flight of India's Geosynchronous Satellite Launch Vehicle, (GSLV-F01), was successfully conducted from Satish Dhawan Space Centre SHAR (SDSC SHAR), Sriharikota on September 20, 2004. GSLV-F01 successfully placed EDUSAT, precisely into the predetermined GTO with a perigee of 180 km and an apogee of 35,985 km with an orbital inclination of 19.2 deg with respect to the equator. GSLV project was initiated in 1990. The first test flight GSLV-D1, was conducted on April 18, 2001 when the 1,540 kg experimental satellite, GSAT-1, was placed in GTO. In the second test flight GSLV-D2, conducted on May 8, 2003, the vehicle launched 1820 kg GSAT-2. In its first operational flight, GSLV launched a higher payload of 1950 kg EDUSAT into GTO with precision. The successful first operational flight of GSLV, coming after the success of both the developmental test flights, has demonstrated its reliability and capability to place 2000 kg class of satellites into GTO. The 49 metre tall, 414 tonne GSLV is a three stage vehicle. The first stage, GS1, comprises a core motor with 138 tonne of solid propellant and four strap-on motors each with 40 tonne of hypergolic liquid propellants (UH25 and N204). The second stage has 39 tonne of the same hypergolic liquid propellants. The third stage (GS3) is a cryogenic stage with 12.5 tonne of Liquid Oxygen (LOX) and Liquid Hydrogen (LH2). The Aluminum alloy GSLV payload fairing is 3.4 m in diameter and 7.8 m long. The three-axis attitude (orientation) stabilisation of GSLV is achieved by autonomous control systems provided in each stage. Single plane Engine Gimbal Control (EGC) of the four strap-ons of the first stage are used for pitch, yaw and roll control. The second stage has EGC for pitch and yaw and hot gas Reaction Control System (RCS) for roll control. Two swivellable vernier engines using LH2 and LOX provide pitch, yaw and roll control for the third stage during thrust phase and cold gas system during coast phase. The Inertial Guidance System in the equipment bay housed above the third stage guides the vehicle till spacecraft injection. The closed loop guidance scheme resident in the on-board computer ensures the required accuracy in the injection conditions. GSLV employs S-band telemetry and C-band transponders for the vehicle performance monitoring, tracking, range safety/flight safety and preliminary orbit determination.
GSLV employs various separation systems such as Flexible Linear Shaped Charge for the first stage, pyro-actuated release mechanism for second stage and Merman band bolt cutter separation mechanism for the third stage. Spacecraft separation is by spring thrusters, mounted at the separation interface. Cryogenic Upper Stage Project (CUSP) GSLV, in its present configuration (GSLV Mk I), uses the Russian supplied upper stage. In GSLV-Mk II, ISRO developed Cryogenic Upper Stage (CUS) will be used which will increase the payload capability from the present 2000 kg to 2500 kg into GTO. CUSP envisages design and development of the indigenous cryogenic upper stage to replace the Russian-supplied cryogenic stage in GSLV. During the year, qualification hot tests of the integrated engine with steering engines were successfully completed on the second engine with two steering engines. Endurance hot test for a duration of 1000 sec and test for simulating off-nominal conditions of operations (120 sec) have been conducted. The third main engine with flight nozzle has been realised and tested successfully for 200 sec as part of acceptance testing. All major subsystem of fourth engine have also been realised. CUS main engine and steering engines have undergone tests for a cumulative duration of more than 5,700 secs and 4,400 secs respectively till now as part of development and qualification. GSLV-Mk III GSLV-Mk III will have a capability to launch 4 tonne satellite into GTO. The project was approved during 2002-03 and the development is expected to take six years. GSLV-Mk III is a three-stage vehicle with a 110 tonne core liquid propellant stage and a strap-on stage with two solid propellant motors, each with 200 tonne propellant. The upper stage will be a cryogenic with a propellant loading of 25 tonne. GSLV Mk-III will have a lift off weight of about629 tonne and will be 42.4 m tall. The payload fairing will have a diameter of 5 metre and a payload volume of 100 cubic metre. During the year, vehicle systems specifications have been generated for all major hardware configurations and interfaces defined. Preliminary design review of all subsystems and the integrated technical review of the project have been completed. Fabrication of S-200 motor cases and other vehicle structures have already commenced. Design reviews of the in-house facilities have been completed and the construction of the facilities commenced.
The structural dynamic data of the vehicle has been generated and the vehicle configuration for the ground resonance testing finalised. Configuration of destruct systems for S-200 and L-110 stages and jettisoning motors for S-200 separation system has been finalised. Spacecraft interface definitions have also been made and are being reviewed. Based on wind tunnel and computational fluid dynamic studies, the aero dynamic coefficient of the vehicle have been revised. A long duration engine qualification test for L-110 has been completed. The preliminary design review of the engine for C-25 cryogenic stage has been completed during the year. Design review of the stage has also been completed. Two series of cold flow test have been conducted on LOX proto type turbine using water. Fabrication of LH2 turbo-pump is progressing.
Design of various avionics systems including command execution modules, power module, integrated actuator and control electronics, inertial systems, etc., has been completed and reviewed. Polar Satellite Launch Vehicle (PSLV) The preparations for the launch of PSLV-C6 to place India's CARTOSAT-1 and HAMSAT satellites have commenced. The launch is expected in the first half of 2005. The mission definition has been finalised for carrying the 1535 kg CARTOSAT-1 and 42 kg HAMSAT into a 622 km sun synchronous polar orbit. PSLV-C7 is planned to launch India's remote sensing satellite CARTOSAT-2 and the Space capsule Recovery Experiment (SRE). The 650 kg CARTOSAT-2 will be launched into 630 km sun synchronous polar orbit. It is planned to employ a Dual Launch Adaptor with the spacecraft mounted over the adaptor and the 600 kg SRE mounted inside. PSLV-C8 mission is intended for launching the AGILE satellite of Italy under a commercial contract. The 360 kg satellite will be launched into a 550 km low earth orbit. The configuration of PSLV (PSLV-C8) with only the core vehicle for launching AGILE satellite has been finalised. Rohini Sounding Rockets
During the year 40 RH-200 rocket flights were conducted including 36 for the MIDAS campaign. An RH-300 Mk II was also launched for mesospheric turbulence and stratification studies. Two RH-200 Mk III flights were also conducted during the year. Space capsule Recovery Experiment (SRE) SRE is intended for demonstrating the capability to recover an orbiting space capsule. The experiment envisages the development of a 500 kg recoverable capsule and the associated technologies. SRE is intended to test reusable thermal protection system, navigation, guidance and control, hypersonic aero-thermodynamics, management of communication blackout, deceleration and floatation SRE comprises aero-thermo structure, spacecraft platform, deceleration and floatation system and micro-gravity payloads. It has a sphere-cone-flare configuration with a spherical nose of about 0.5 m radius, base diameter of 2 m and 1.6 m height. The capsule is made of mild steel. The parachute, pyro devices, avionics packages of triggering unit and sequencer, telemetry and tracking system, sensors for measurement of system performance parameters are placed inside SRE capsule. After its launch by PSLV, SRE will remain in orbit for a few days during which it will be used to perform experiments in micro-gravity environment. The capsule will then be de-orbited and it reenters the earth's atmosphere. On reentry, after initial aerodynamic braking, a parachute system will reduce the touch down velocity. SRE will splashdown in the Bay of Bengal, about 140 km east of Sriharikota coast. A floatation system will keep SRE afloat and enables its recovery. During the year, three airdrop tests have been conducted successfully using aircraft for testing deceleration and flotation system. Three drop tests of the instrumented SRE were successfully conducted using a helicopter during June-August, 2004 from SDSC SHAR. Air Breathing Propulsion Research and development activities related to air breathing propulsion has continued during the year. More than 100 supersonic combustion tests have been carried out for 2.5 kg/sec combustor. Design of 5 kg/sec combustor has been made. Feasibility studies have also been completed for technology demonstration of scramjet propulsion using a sounding rocket. Launch Infrastructure The second launch pad at SDSC SHAR has undergone commissioning trials. The propellant mockup trials for PSLV/GSLV second stage and L-40 stage and other support systems like satellite cooling, umbilical retraction, cryo arm retraction, etc. have all been successfully completed. Mockup for the cryogenic stage is planned during 2005-06. The launch of PSLV-C6 carrying CARTOSAT-1 is planned from the second launch pad during the first half of 2005. Work related to new solid propellant plant, vehicle assembly and test facilities, range instrumentation and computer systems and propellant servicing facilities for GSLV Mk-III have made substantial progress at SDSC SHAR. Civil works related to satellite preparation facilities and L-110 preparation facilities have already reached advanced stages of completion. |
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