Even as GSAT-6A stays mum, ISRO readies satellite for April 12 Even as the Indian Space Research Organisation (ISRO) is making efforts to reestablish link with the GSAT-6A satellite, the space agency has one more launch lined up for next week. The launch of the IRNSS-1I navigation satellite is scheduled from the Satish Dhawan Space Centre in Sriharikota, tentatively slotted on April 12. The IRNSS-1I Navigation Satellite has already reached the spaceport after it was transported from Bengaluru last month. Though ISRO officials have maintained that all future missions are on schedule despite the GSAT-6A setback, the launch of the IRNSS-1I is giving jitters to the space agency. To add to the nervousness, this will be the first time that the testing, assembling and integration have been entirely done by the private sector. The IRNSS-1I is a replacement to a satellite whose launch was a failure. The PSLV-C41, which will launch the IRNSS-1I, itself is a replacement for the IRNSS-1H which was declared a failure after the satellite separation occurred within the heat shield of the PSLV-C39 launched on August 31 last year. The committee looking into what led to failure of PSLV-C39 mission (the first involving a PSLV rocket in 24 years) concluded that inadequate pressure buildup in the bellow led to the failure of ISRO’s PSLV-C39. Incidentally, the IRNSS-1H was to replace the IRNSS-1A, the first of the seven IRNSS satellites, launched in 2013. ISRO had hoped that with the launch of the IRNSS-1H the three atomic clocks of the IRNSS-1A which stopped working in 2016 would be rectified. Meanwhile more than three days after it lost contact with the GSAT-6A satellite, the space agency is still making efforts to establish the link with the satellite which snapped while the third orbit raising manoeuvre was to be fired on April 1.