GSLV MkIII-D1/GSAT 19 mission was launched successfully on June 05,2017 from the Second Launch Pad at Satish Dhawan Space Centre, Sriharikota. It is the first developmental flight of GSLV MKIII, a heavy lift launch vehicle. GSLV MKIII can lift payloads up to 4 tonnes into Geosynchronous Transfer Orbit (GTO) and 10 tonnes into Low Earth Orbit (LEO).
GSLV MkIII Vehicle
GSLV MkIII-D1 is a three stage vehicle. First stage has two solid strap-on motors, S200, with a composite solid propellant, second stage, L110, has hypergolic liquid, while the third stage, C25, is a cryogenic upper stage. All these three propulsion elements are new developments. The C25 cryogenic stage carries around 28 tons of cryogenic propellants. These are stored on-board at very low temperatures. This cryogenic stage will facilitate the payload to reach the intended orbit.
GSLV Mk-D1 is advanced than the previous missions in multiple aspects. The navigation, Guidance and Control system and stage separation systems are all part of this mission. The vehicle performance and its flight status are closely monitored by S-band telemetry and C-band transponder respectively.
The main payload for this mission, GSAT 19, with lift-off mass 3136 Kg and dry mass 1394 Kg, is a high throughput communication satellite, the heaviest ever launched from India.It is a cuboid shaped Geostationary Communication Satellite, built around a CRPF central cylinder. The power generation in the satellite is taken care by Ultra Triple Junction solar cells that generate about 4500 Watts of electrical power. For the orientation reference for the satellite, Sun, Earth and star sensors as well as gyroscopes are provided. The attitude and Orbit Control System (AOCS), with the help of momentum wheels, magnetic torquers and thrusters, maintains the satellite’s orientation. A 440 N Liquid Apogee Motor and eight 10 N and eight 22 N chemical thrusters is used as the satellite’s propulsion system for initial orbit raising and station keeping.
For high throughput communication, GSAT-19 carries Ka/Ku-band high throughput communication transponder. 1.4m reflector on Earth viewing face and two 2 m deployable reflectors are used as communication antennas. Also, Geostationary Radiation Spectrometer (GRASP) payload is carried to monitor and study the nature of charged particles and the influence of space radiation on satellite and their electronic components.
This mission GSLV MkIII-D1 has a life span of 10 years.