ISRO’s GSLV-6 Launch: Features

ISRO’s GSLV-6 Launch: Features

Question: ISRO has made its second successful GSLV launch using the indigenous cryogenic engine. Elaborate on this scientific and technological breakthrough, keeping the features of the GSAT-6 in mind.

- ISRO cleared doubts regarding cryogenic capabilities through the launch of the Geostationary Satellite Launch Vehicle/ GLSV-D6 placing the satellite in orbit

- GSAT-6 is a 2117 kg communication satellite in orbit

- This is the second and successful launch of GSLV using the indigenous cryogenic engine; the first one was a failure

- GSLV- D6 carrying GSAT-6 lifted off from Sriharikota spaceport

- This marked the 9th flight of the GSLV

- Rocket injected GSAT-6 into the Geosynchronous Transfer Orbit/GTO

- GSAT-6 provides communication through 5 spot beams in S-band and a national beam in C-Band for strategic users

- An advanced feature of the GSAT-6 is the S-Band Unfurlable Antenna for 6 m diameter

- This is the biggest satellite antenna realised by ISRO with a life of 9 years

- GSAT will be used for military purposes

- GSLV-D6 was configured with all three stages including cryogenic upper stage

- The metallic payload fairing of GSLV-D6 had a diameter of 3.4 m

- Overall length of GSLV-D6 was 49.1 mass with lift off mass of 416 tonne

- Cryogenic upper stage on GLSV-D6 was designated as CUS-06

- Cryogenic rocket stage is more efficient and provides for more thrust for every kilogram of propellant burnt by it compared to solid and earth storable liquid propellant rocket stages

- Cryogenic stage is technically a complex system in comparison with earth storable liquid propellant stages on account of its use of propellants at temperatures which are extremely low and the thermal and structural challenges associated with it

- Oxygen is liquified at -183 degree celsius and hydrogen at -253 degree celsius

- Propellants at these low temperatures are revved up using turbo pumps running at 40,000 rpm

- Main engine and two smaller steering engines of CUS have developed nominal thrust of 73.55 kN in vacuum

- At the time of the flight, CUS fires for nominal duration of 720 seconds

- S-band and B-band transponders enable GSLV-D6 performance tracking, monitoring, range safety/flight safety and preliminary orbit determination

- This satellite will be fine tuned into the final geostationary orbit at 83 degree east longitude

- National space agency has been increasingly confident of launching heavy weight rocket with indigenous cryogenic upper stage that can lift payloads of around 2.2 tonne

- The satellite is cuboid shaped and one of its kind S-Band unfurl able antenna with diameter of 6m.

Facts and Stats

- This is the fifth developmental flight of the GSLV and the third carrying the indigenous CUS

- This satellite has a oval shaped GTO and it has a perigree of 168 km and apogee of 35,939 km with orbital inclination of 20.01 degrees in relation to the equator

- The satellite was 49 m tall and had a tonnage of 416

- 4 liquid propellant strap on stages of GSLV-D6 each of them carrying 42 tonne of liquid propellants were ignited

- Its mass is 985 kg and dimensions are 2.1x2.5x4.1m

- Power generated by this satellite is 3100W

- GSATT-6 is the 25th geostationary communication satellite built by ISRO and 12th in the GSAT series

5 predecessors of GSAT-6 were launched in the following years :

- 2001
- 2003
- 2004
- 2007
- 2014