For launching satellites into the low-Earth orbit. High performance for the polar sun synchronous orbit. The METSAT mission in which the weather satellite, later named kalpana-I, was launched. While a GSLV typically places 2 tonnes in a geosynchronous transfer orbit (GTO), the weight of the payload (METSAT) was set at 1,055 kg. Increasing the velocity of PSLV But the increased height of the orbit demanded additional velocity. The ISRO scientists increased the nozzle area ratio of the rocket by reducing the throat, and by having a lighter nozzle on the motor. The efficiency of the rocket increased. The mass of the third stage was reduced by nearly 70 kg and more powerful solid propellants were used. The fuel capacity of the liquid fourth stage was increased from 2 kg to 2.5kg, and its burn time was also increased by 25 per cent.]]>