ISRO’s latest satellite in the INSAT series, INSAT-3A, launched on April 10, 2003, has taken over the Satellite Aided Search and Rescue services that were being provided by INSAT-2B so far. INSAT-2B, which was launched in July 1993, has outlived its design life. INSAT-3A is the only geostationary satellite at present, which is providing Geostationary Orbit Satellite Aided Search and Rescue services (GEOSAR) in this part of the globe, covering Europe to Australia in the Indian Ocean and the Australian regions. Two American satellites, GOES(W) and GOES(E) provide these services on the Western Hemisphere. Satellite Aided Search and Rescue service is provided under the international COSPAS-SARSAT system that provides location information of the distress signals transmitted by beacons mounted on board ships, aircraft or those carried by individuals. The GEOSAR transponder on INSAT-3A complements the Low Earth Orbit COSPAS-SARSAT satellites in receiving the distress signal transmission and its detection.
The ISRO Telemetry, Tracking and Command Network (ISTRAC) operates two ground stations to receive and process the distress signals detected by Low Earth Orbit COSPAS-SARSAT spacecraft besides a ground station capable of receiving and processing distress signals detected by the GEOSAR transponder of INSAT spacecraft in the geostationary orbit. The Mission Control Center is located at Bangalore. The location and other details of the beacon, transmitting the distress signals, are determined instantaneously and informed to rescue coordination centres for carrying out search and rescue operations of the affected ship, aircraft or individuals. It may be noted that ISRO, as the nodal agency in India for the COSPAS-SARSAT system, has helped in saving about 1,400 lives in the last 12 years by providing timely distress alerts.
For example, on August 17, 2002, the Indian Mission Control Center detected a distress signal from a Cyprus registered motor vessel in the Arabian Sea and alerted the Indian Cost Guard. All the 22 crew members on board the vessel were rescued by another vessel. In another incident on September 23, 2002, all the 18 crew members of a Turkey registered motor vessel were rescued before the vessel sank in the Bay of Bengal, thanks to the distress signal detected by the Indian Mission Control Center and the alert given to Indian Coast Guard.