Polar Satellite Launch Vehicle (PSLV)
Uploaded by msnarayana on Oct 15, 2012
The Polar Satellite Launch Vehicle, commonly known by its abbreviation PSLV, is an expendable launch system developed and operated by the Indian Space Research Organisation (ISRO). It was developed to allow India to launch its Indian Remote Sensing (IRS) satellites into sun synchronous orbits, a service that was, until the advent of the PSLV, commercially viable only from Russia. PSLV can also launch small size satellites into geostationary transfer orbit (GTO). The PSLV has launched 41 satellites (19 Indian and 22 from other countries) into a variety of orbits to date.
PSLV costs 17 million USD flyaway costs for each launch.
Development
PSLV has been designed and developed at Vikram Sarabhai Space Centre (VSSC), Thiruvananthapuram, Kerala. The inertial systems are developed by ISRO Inertial Systems Unit (IISU) at Thiruvananthapuram. The liquid propulsion stages for the second and fourth stages of PSLV as well as the reaction control systems are developed by the Liquid Propulsion Systems Centre (LPSC), also at Thiruvananthapuram. The solid propellant motors are processed at Satish Dhawan Space Centre SHAR, which also carries out launch operations.
After some delays, the PSLV had its first launch on 20 September 1993. Although all main engines performed as expected, an altitude control problem was reported in the second and third stages. After this initial setback, ISRO met complete success with the third developmental launch in 1996. Further successful launches followed in 1997, 1999, and 2001.
PSLV continues to be the work horse of Indian satellite launches, especially for LEO satellites. It has undergone several improvements with each subsequent version, especially those involving thrust, efficiency as well as weight.
Vehicle description
The PSLV has four stages using solid and liquid propulsion systems alternately. The first stage is one of the largest solid-fuel rocket boosters in the world and carries 138 tonnes of Hydroxyl-terminated polybutadiene (HTPB) bound propellant with a diameter of 2.8 m. The motor case is made of maraging steel. The booster develops a maximum thrust of about 4,430 kN. Six strap-on motors, four of which are ignited on the ground, augment the first stage thrust. Each of these solid propellant strap-on motors carries nine tonnes of HTPB propellant and produces 677 kN thrust. Pitch and yaw control of the PSLV during the thrust phase of the solid motor is achieved by injection of an aqueous solution of strontium perchlorate in the nozzle to constitute Secondary Injection Thrust Vector Control System (SITVC). The injection is stored in two...