The PSLV (Polar Satellite Launch Vehicle) is a launch vehicle designed by the Indian Space Research Organisation (ISRO) at the Vikram Sarabhai Space Centre in Thiruvananthapuram. It is designed to launch 1000kg - 1200kg payloads into low earth orbit (LEO) or into a geosynchronous transfer orbit (GTO). It began service in 1994 and has had 2 successful development flights and 5 successful commercial flights (as of December 2006).
Launch Profiles
PSLV is called a "polar" launch vehicle because it was originally designed to inject payloads into 88-89 degree inclined, sun-synchronous circular orbit approximately 800km in altitude.
Beginning with the seventh flight (PSLV-C4) in September 2004 the PSLV launch profile was modified to place the Kalpana 1 (MetSat 1) primary payload into the GTO elliptical (250km x 36,000km) orbit at 18 degrees of inclination. From this orbit Kalpana executed a Hohmann-Transfer maneuver to reach it's geosynchronous location.
Launch Vehicle Configuration
The PSLV is a four stage launch vehicle with a lift weight of 294 metric tonnes. It stands 44.4m tall, and employs both solid and liquid fueled technology. The stages are:
Stage 1 - A 138 tonne HTPB (hydroxyl-terminated polybutadiene) based solid fuel booster with six 9.0 tonne strap-on rockets. The first stage produces a total thrust of 8600 kN (kilo-Newtons) over a burn time of 107.4 seconds.
Stage 2 - a 40.6 tonne UDMH (unsymmetrical dimethylhydrazine) and N2O4 (dinitro-tetroxide) liquid fueled motor. The second stage produces 725 kN of thrust over a burn time of 163 seconds.
Stage 3 - a 7.2 tonne HTPB based solid fuel booster. The third stage produces a maximum thrust of 340 kN over a burn time of 76 seconds.
Stage 4 - a 2.0 tonne MMH (monomethylhydrazine) + N2O4 bi-propellant fueled motor. It produces a maximum 7.4 kN per burn and can execute two burns for injecting payloads into orbit during the coast phase.
All four stages have control methods for pitch, yaw and roll The first stage primarily uses thrusters; the second and fourth stages use engine gimbals and the third stage employs a flex nozzle.
Launch Location
PSLV launches take place at ISRO's Satish Dhawan Space Centre (SHAR) in Sriharikota, 13.7N, 80.25E, about 100 km north of Chennai on India's eastern coast.
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Author(s): Emileigh Starbrook (unknown date prior to 2007 December 31)
