ISRO to Test New GSLV Mark III Booster on Thursday

GSLV Mk-III mock-up at the second launch pad. (Credit: ISRO)
GSLV Mk-III mock-up at the second launch pad. (Credit: ISRO)

The Indian space agency ISRO is set to conduct the first test flight of its largest ever booster, the Geosynchronous Launch Vehicle Mark III, on Thursday.

“GSLV Mk III is conceived and designed to make ISRO fully self reliant in launching heavier communication satellites of INSAT-4 class, which weigh 4500 to 5000 kg,” ISRO says on its website. “It would also enhance the capability of the country to be a competitive player in the multi-million dollar commercial launch market. The vehicle envisages multi-mission launch capability for GTO, LEO, Polar and intermediate circular orbits.”

The L110 liquid core stage being prepared at stage preparation facility. (Credit: ISRO)
The L110 liquid core stage being prepared at stage preparation facility. (Credit: ISRO)

The suborbital test flight from the Satish Dhawan Space Centre will include the Crew Module Atmospheric Re-entry Experiment (CARE), a prototype of a spacecraft capable of carrying a crew into orbit. ISRO is looking to launch human spaceflights sometime in the 2020’s.

CARE at clean room before its launch. (Credit: ISRO)
CARE at clean room before its launch. (Credit: ISRO)

The GSLV Mark III’s first stage consists of two S200 rocket boosters with 200 tonne solid propellant that are strapped to the restartable L110 re-startable liquid second stage. For the first test flight, the third stage consists of a passive C25 cryogenic upper stage.

The new booster is designed to be more powerful than the GSLV Mark I and II boosters with which ISRO has been launching satellites over the past 13 years.

GSLV Mark III
GSLV Mark II
Liftoff Weight630 tons414 tons
Payload4 tons to GTO2 to 2.5 tons to GTO
Height42.4 meters49 meters
Stages33

The GSLV Mark I and II have a poor success record since the first launch in 2001. The GSLV Mark I has been launched six times with two successes, three failures and one partial failure. The larger GSLV Mark II has been launched twice with one success and one failure.