ISRO says ‘confidence up’ on Dec. launch of 4-tonne rocket

The much-needed indigenous heavy-lift space launcher, GSLV-MkIII, looks set for a full-fledged first flight in December after its cryogenic engine passed a test to qualify it for use in future missions.

The engine was test fired for 640 seconds on Friday evening at the Mahendragiri test facility of Indian Space Research Organisation. This is the time the cryogenic stage will be in action during an actual GSLV-MkIII flight.

“Today’s cryogenic engine test for the MkIII was successful,” said ISRO Chairman A.S. Kiran Kumar, who witnessed the critical event along with senior officials involved in rocket development activities. “It gives us the confidence to go ahead [with its other activities] and more or less confirm a full launch of GSLV MkIII in December.” Tested once in mid-2015 for 800 seconds, the engine prototype, he said, has proven that it can repeat the performance equally on a second or different hardware. Its design would be frozen, replicated for use in the cryogenic third stage of upcoming MkIII rockets. When it gets regularised in the coming years, the GSLV-MkIII launcher (some call it the LVM3) will be able to lift four-tonne communication satellites into their specified orbit. That is twice heavier than what the present indigenous GSLV-MkII can do.

Stage test next

Calling it “100 per cent success,” S. Sivan, Director of the rocket-related hub, Vikram Sarabhai Space Centre, Thiruvananthapuram, said, “There is confidence that we are going in the right direction” with the cryoengine design. In a couple of months, they would test the entire cryogenic third stage, called C-25, with fuel tank, plumbing and other systems.