The Indian Space Research Organisation (ISRO) is all set to launch India's heavy rocket Geosynchronous Satellite Launch Vehicle-Development 5 (GSLV-D5) from the spaceport at Sriharikota, Andhra Pradesh at 4.18 pm Sunday. The 29-hour countdown for the launch of GSLV-D5 with the indigenous engine began Saturday 11.18 am.