ISRO launched the communication satellite, GSAT-7A with GSLV-F11 (Geosynchronous Satellite Launch Vehicles).
What is GSAT-7A?
GSLV-F11 injected GSAT-7A into a Geosynchronous Transfer Orbit (GTO) very close to the intended orbit.
GSAT-7A is an advanced communication satellite with a Gregorian Antenna and other new technologies.
GSAT-7A is the 39th Indian communication satellite of ISRO to provide services to users in Ku-band over the Indian region.
The satellite operating in the Ku band will service communication needs for network-centric operations of the Indian Air Force and the military.
Most of the functional requirements of the communication payloads and other systems have been derived from ISRO’s earlier geostationary INSAT/GSAT satellites.
What is the key feature?
At 2,250 kg, GSAT-7A is the heaviest satellite launched by GSLV-Mk-II since it began using the indigenous cryogenic engine.
The cryogenic stage of this vehicle has been modified to increase the thrust rate.
The rocket was pushing the limits of its capabilities in launching satellites of the two-tonne class for the seventh time.
This is a standout factor with this launch and 12 other successful flights carried out so far by ISRO’s GSLV-Mk-II rocket.
They include six successive flights since 2014 with an indigenous cryogenic fuel upper stage.
What is ISRO's GSLV programme?
GSLV-Mk-II is ISRO’s fourth generation rocket with three stages.
The first stage has four liquid strap-ons and a solid rocket motor.
The second has a high thrust engine using liquid fuel, and the third is the cryogenic upper stage.
The indigenous cryogenic engine was tested successfully for the first time in 2014.
The cryogenic stage uses liquid hydrogen as fuel and liquid oxygen as an oxidiser.
Compared to solid and earth-storable liquid propellant stages, it is a highly efficient rocket stage that provides more thrust for every kg of propellant it burns.
ISRO initially used 7 cryogenic engines sold by Russia for the early phase of its GSLV programme that began in 2001.
GSLV launches with Russian engines have had mixed success, with only two flights performing well.
ISRO is developing a more powerful, fifth-generation GSLV-Mk-III rocket to launch satellites in the 4-6-tonne category.
GSLV-Mk-III had a successful development flight recently when it launched the 3,423-kg GSAT-29 communication satellite.
GSLV-Mk-III is the designated launch vehicle for India’s upcoming second moon mission and the first human space flight scheduled for 2022.
