GSAT-19 is a Geostationary Communication Satellite developed by ISRO primarily to test its modular I-6K satellite bus. It carries Ka/Ku-band high throughput communication transponders, Geostationary Radiation Spectrometer (GRASP), ion thrusters for manoeuvring and stabilisation, miniaturised inertial reference unit, indigenously produced lithium-ion batteries, thermal radiators and C-band traveling-wave-tube amplifiers.
The rocket was launched into orbit through GSLV-Mk III-D1 rocket yesterday. GSAT-19 used its own propulsion system to reach it geostationary orbital home after it got successfully separated from the launcher.
Geosynchronous Satellite Launch Vehicle Mark II (GSLV MkII) is the largest vehicle developed by India which is currently in operation. It contains three stages with four liquid strap-on boosters. The Cryogenic Upper Stage (CUS) which is indigenously developed is flight proven and this forms the third stage of GSLV MkII. The design and development of the rocket is based on ISROs battle tested experience in handling solid, liquid and cryogenic rocket propulsion technologies.
The cryogenic stage of the C25 carries at very low temperatures about 28 tons of cryogenic propellants stored on board. After the separation of the L110 stage about 322 seconds after lift-off, the ignition of the C25 stage takes place after a buffer of 2 seconds. C25’s operational duration is about 643 seconds, which enables GSAT-19 carried on board to reach the intended GTO. All the three propulsion elements of GSLV MkIII are new developments. Other advanced systems includes the navigation, guidance and control system and the stage separation systems.