The launch is crucial for India as it seeks to prove the design, realisation and sustained firing of its indigenously built cryogenic engine after two back-to-back failures of the GSLV flights in 2010 -- the first, with an indigenous cryogenic engine, on April 15 and the next -- with a Russian cryogenic engine, on December 25.

The launch of the last GSLV was called off at the eleventh hour due to a fuel leak in its second stage -- in a setback to the mission to test its homegrown cryogenic engine -- after its failure three years ago.