Filling of liquid fuel in the second stage of the Rs 70-crore Polar Satellite Launch Vehicle (PSLV) rocket that would carry the Rs130-crore Oceansat2 -- India's remote sensing satellite -- Wednesday afternoon was progressing smoothly at India's rocket launch centre in Sriharikota, around 80 km from Chennai.
The PSLV would also carry six other nano satellites. The 51-hour countdown for the sixth flight of PSLV's core alone version (rocket without its six strap on motors) started Monday 9 am.
Speaking to IANS from Bangalore, S Satish, director, publications and public relations of the Indian Space Research Organisation (ISRO), said: "The four-stage rocket uses solid and liquid fuel alternatively. The first and third stages are fired by solid fuel and the third and fourth stages are powered by liquid fuel."
While the solid fuel is cast ready, the liquid fuel will be filled in the two days preceding the rocket launch.
According to S Satish, filling of the second stage with 41.5 tonnes of fuel will take around 10 hours.
Into the flight, the second stage fuel will burn for 147 seconds developing a maximum thrust of 799 kilo Newton (kN) -- a Newton is a measure of force needed to accelerate one kilogram mass at one metre per second squared.
The first stage carrying 139 tonne propellant is one of the largest solid propellant boosters in the world and will burn for 101 seconds to develop 4,817 kN.
The third stage uses 7.6 tonne of solid fuel (112 seconds burning time; thrust 238kN) and the fourth has twin-engine configuration with 2.5 tonnes of liquid propellant that will burn for 497 seconds and the thrust will be 14.6kN -- both engines put together.
According to Satish, the rocket will blast off the first launch pad at 11.51 a.m. Wednesday for its flight during which it would earn an unspecified amount of dollars as the carriage fee from the European owners of six nano satellites, piggy backing on the 960kg Oceansat2.
The Indian satellite will be ejected into a sun-synchronous orbit 720 km above the earth and it will cover the whole earth, as the coverage strip will be moving.
The orbit is designed in such a way that the satellite will cross the Equator at 12 noon near India.
A global leader in remote sensing data, India has till date launched 15 remote sensing satellites of which nine are still in operation.
Even the Oceansat1 launched in 1999 is in service and will go into oblivion slowly.
According to Satish, the design life of Oceansat2 is five years and it may outlast that period like its earlier version.