The Indian Space Research Organisation (ISRO) said the reason behind Geo-Synchronous Satellite Launch Vehicle (GSLV-D3) deviating from its path was non-ignition of the cryogenic engine causing failure of the mission.

The spokesperson for the agency, S. Satish said, "The cryogenic engine has not ignited, that is for sure. Why it has not ignited, the reasons have to be found out."

A probe has been launched to determine the causes of the failure of the cryogenic engine. The Geosynchronous Satellite Launch Vehicle a three stage rocket where the cryogenic engine takes over after the first two stages separate. The mission was put in orbit an advanced communications satellite called G-Sat, along with other instruments.

The indigenously developed cryogenic engine was deployed for the first time in a GSLV rocket. The launch was normal up to stage two but then the cryogenic engine did not ignite and the rocket fell into the sea.

The cryogenic engine has been reviewed many times by specialists in cryogenic technology and academicians and had given a go ahead. Its failure to ignite puzzled many experts working on the technology. The engine was also tested on ground for 7,767 seconds, while it would fire for only 720 seconds while on board the rocket.

ISRO Chairman K. Radhakrishnan said that the engine cleared tests on the ground however to ignite it in the vacuum of space is a challenge as it cannot be simulated on the ground. Experts say that the ignition in vacuum can only be done on the flight.