The Indian Space Research Organisation (Isro), whose maiden launch attempt of the small satellite launch vehicle (SSLV) did not manage to put the satellites into their desired orbit is back on rectifying errors before the second developmental flight planned for later this year
ISRO officials have said they are looking at 50 to 60 launches every year with the SSLV. That would practically be one launch every week, a sharp contrast from the 2-3 launches every year that ISRO has been able to manage.
SSLV is made low cost, low turnaround time in mind with launch-on-demand flexibility under minimal infrastructure requirements.
What’s SSLV ?
The Small Satellite Launch Vehicle (SSLV) is a three-stage launch vehicle with three solid propulsion stages and liquid propulsion based Velocity Trimming Module (VTM) as a terminal stage.
Weighing around 110 tonne, SSLV is a 34-meters tall ,2-metre diameter (width) launch vehicle having a lift-off mass of around 120-tonne.
Why Isro Built It ?
Isro developed the SSLV to cater the launch of up to 500kg satellites to Low Earth Orbits (LEO) on ‘launch on demand ‘ basis. That is a low cost rocket with low turn-around time, flexibility in accomodating multiple satellites, launch on demand feasibility needing minimal launch infrastructure requirements, means SSLV provides low cost acces to Space.
This will help India gain advantage in agrowing launch services market, especially at a time when multiple new countries and private players from developed nations are seeking access to space.
Features of SSLV:
SSLV is configured with three solid stages – 87 tonne;7.7 tonne and 4.5 tonne- while satellite insertion into the intended orbit is achieved through a liquid propulsion-based velocity trimming module (VTM), which is the terminal stage.
All three solid stages use heterogenous propellent based thrusters. The first has a thrust of 2,496kN , the second : 234.2kN and third 160kN. The VTM is based on 50N bipropellent thrusters with eight 50N thrusters for RCS and eight 50N thrusters of velocity addition.
The Rocket is capable of launching mini,micro or nanosatellites (10 to 500kg) to a 500km planer orbit.
First Mission (Aug 7):
After years of development, the first developmental flight pf SSLV- the SSLV-D1 which was carrying a micro remote sensing satellite (EOS-02) and another satellite AzaadiSAT – was scheduled for launch on August 7, 2022 at 9:18 AM from Satish Dhawan Space Centre, Sriharikota.
The SSLV-D1 mission was to launch EOS-02, a 135kg satellite into LEO of about 350 km to the equator, at an inclination of about 37 degrees. EOS-02 is an earth observation satellite by ISRO. The microsat series offers advanced optical remote sensing operations in infra-red bands with high spatial resolution.
The other satellite – AzaadiSAT- was a “8U Cubesat weighing around 8kg” and carrying 75 different payloads each weighing around 50 grams and conducting femto-experiments. Girl students from rural regions across the country were provided guidance to build these payloads.
However, the SSLV-D1 failed to place the satellites into the desired orbit due to an anomaly.
