Geosynchronous Satellite Launch Vehicle-Mark III (GSLV-Mk III) will be launched into space at 5.28pm along with GSAT-19.
If launched successfully, "Fat Boy" will be the heaviest satellite into orbit by an Indian rocket till date. "If today India has to launch communication satellites beyond 2.3 tonnes, we have to go overseas", Radhakrishnan told PTI.
ISRO's GSAT-18 communication satellite weighing 3,404 kg was launched in October past year using the European Ariane 5 VA-231 launch vehicle. ISRO officials told IANS that due to the increase in the diameters of various stages, the height got reduced despite a drastic increase in the weight - from around 415-tonne of GSLV-Mk II to 640-tonne in GSLV-Mk III.
"Today is a historic day".
Congress president Sonia Gandhi also lauded ISRO for the successful launch and said it was another significant achievement which made the nation proud. Besides, it carries a geostationary radiation spectrometer (GRASP) payload to monitor and study the nature of charged particles and the influence of space radiation on satellites and their electronic components.
Although India has been dreaming big in space - mulling a manned mission to space and interplanetary missions to Venus and Jupiter, its lack of heavy lift technology remained a hurdle in giving concrete shape to those plans.
The GSLV-MkIII is a three-stage vehicle created to carry heavier communication satellites into GTO.
GSAT-19 satellite with a lift-off mass of 3136 kg is the communication satellite of India, configured around the ISRO's standard I-3K bus. Meanwhile, Director of the ISRO propulsion complex, P V Venkata Krishnan described the launch vehicle as a game changer and said that the organisation had made quantum leaps when it came to hardware. The thrust of the complex engine is 20 tonnes, capable of lifting payloads of upto 4-tons to a geosynchronous transfer orbit.
The second and core stage is fueled by liquid propellants.
With this India has joined the elite club of launching a heavy satellite+ (above 2,300 kg).
The success of the GSLV Mk III also paves the way for ISRO to enter newer avenues like the human spaceflight programme, which it plans to carry out in the next decade.