Simulation and experiments to assess cause of Gslv failure

         Isro is currently simulating the Christmas day failure of the Geo Synchronous Satellite Launch Vehicle (GSLV) and conducting a series of experiments to determine the cause of 10 connectors of three-stage rocket snapping which resulted in the mission ending in the Bay of Bengal, G.Madhavan Nair, who is chairing the failure analysis committee, stated.

       On December 25,2010, the rocket deviated from its designated trajectory and broke up 53.8 seconds after lift off. The destruct command was flashed 64 seconds after launch. The failure was a huge set back to Isro. It was the first time that an Indian rocket was ferrying the heaviest indigenous satellite, the 2300 kg GSat-5 Prime communication satellite. Initial speculation that the huge weight of the satellite could have caused the set back has not gained much ground.

       Speaking to ``Beyond Moon and Mars (BMM)'' , Nair, a former Isro chairman, said that these simulations and analysis will go on for several weeks. ``Only after this we will be able to arrive at a firm conclusion as to why the connecters snapped,’’ he said. This failure analysis exercise is being conducted largely at the Vikram Sarabhai Space Centre (VSSC) in Thiruvanathanapuram.

        Nair was in Mumbai to deliver the convocation address at Mumbai University.

        He said that the failure analysis committee has also saught data from the Russians since the connectors passed between the Russian cryogenic engine and rocket’s equipment bay. Some of these connectors carry command signals from the on board computer residing in the equipment bay located near the top of the vehicle to the control electronics of the four L40 strap-ons in the first stage of the rocket.  

        The former Isro chief said that similarly, simulations were also being carried out to find out why the maiden flight of the Indian cryogenic engine on the Gslv on April 15, 2010 was unsuccessful. He said that the failure of the two Gslv missions --one caused by the indigenous cryogenic engine and the other due to the snapping of 10 connectors—could possibly impact on the launch time table of the second Indian mission to the moon, Chandrayaan-2.

         The joint Indo-Russian lunar flight is slated for lift off in 2013. ``But some delay cannot be ruled owing to all these factors,’’ he speculated. But, Isro has expressed confidence that despite these circumstances the second Indian moon will take off in 2013 according to the original schedule.

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