The Polar Satellite Launch Vehicle (PSLV) is an Indian Rocket, which is one of the most advanced and reliable rockets currently under development by the Indian Space Research Organisation (ISRO). The rocket has a total mass of 321 metric tonnes, and a height of 44.5 m. The launch site is usually Satish Dhawan Space Centre (SDSC), on Sriharikota Island on the east coast of India.
Very early in the programme, they had a few setbacks where the rockets exploded after liftoff; however, they learnt from these mistakes and improved their production. Explosions after launch are always a risk for any rocket manufacturer and even the best such as NASA have had to deal with failure, however ISRO learnt from their mistakes and made the correct improvements, such that today PSLV is a very reliable workhorse.
Many Europeans scoff and question why India should have a space programme, when millions of her people are starving. However, spacecraft and rocket development is a profitable venture, which generates money. The profits from this venture go towards feeding the hungry and making homes for the homeless.
India has extremely intelligent scientists, engineers, and designers, who form the backbone of ISRO. There is no reason why these scientists should not apply their skills and simultaneously earn money for their country to better their people. Sending satellites into space is good profitable business, and consequently they plan to be a core provider of this service on the Asian continent. If you need a satellite, then they will build it for you and place it into orbit as well, and with a young and intelligent workforce, they can be extremely competitive.
The rocket is a fully realised Indian design, and manufactured completely in India. It uses unique technologies to achieve the goal of sending satellites into space. The rocket has four stages and each stage uses alternating solid and liquid propulsion fuels. The design is fully modular allowing multiple stages to be added or removed depending upon the payload mass. Currently there are five versions of this rocket to cater for a wide range of payloads.
The launch vehicle has seen many revisions and improvements increasing its reliability even further. Currently, this is the most affordable rocket in Asia, for any sized payload. Its low cost has attracted many countries across the globe to launch their own satellites. Today, even NASA is considering using them.
PSLV is the standard version consisting of four stages and six booster rockets, with the capability to launch a maximum of 1600 kg to a distance of 622 km high into a Sun Synchronous Orbit (SSO).
PSLV-CA is the “Core Alone” version without any boosters, with the capability to launch a payload of 1100 kg into SSO.
PSLV-XL is a more powerful version with boosters, and a payload capacity of 1600 kg.
Three-Stage PSLV is the second stage of a four-stage rocket used for delivering smaller payloads of up to 500 kg to a Low Earth Orbit (LEO).
PSLV-HP is a higher performance version with an improved efficiency engine capable of carrying payloads of up to 2000 kg.
PSLV-21 is one of the most advanced rockets in their portfolio having successfully launched a 712 kg French satellite.
The PSLV series launched the “Mars Orbiter”, however, now they are focusing their efforts on a new range of bigger rockets. The Geosynchronous Satellite Launch Vehicle (GSLV) is an even bigger rocket based on PSLV technology, and capable of carrying much larger payloads. The GSLV Mark 3 has already successfully carried satellites into orbit and this is the rocket to use for larger spacecraft missions to Mars.
Stage 1 fuel consists of a solid propellant hydroxyl-terminated poly-butadiene (HTPB), providing a burn time of 102 seconds and a thrust of 4787 kN.
Stage 2 fuel is unsymmetrical dimethyl hydrazine mixed with 25 % hydrazine hydrate (UH25 + N204), which is a liquid propellant with a burn time of 148 seconds and 804 kN of thrust.
Stage 3 fuel is HTPB same as stage one and has a burn time of 110 seconds providing a thrust of 242 kN.
Stage 4 fuel is mono-methyl hydrazine + mixed oxides of nitrogen (MMH + MON-3) which is a liquid propellant providing a burn time of 526 seconds and a thrust of 7.3 × 2 kN.