Appendix - Satellite Systems - mcmurdo 406 EPIRB User Manual

13. APPENDIX – SATELLITE SYSTEMS
COSPAS-SARSAT satellite system
The COSPAS-SARSAT system provides distress alert and location information to search
and rescue authorities anywhere in the world for maritime, aviation and terrestrial users in
distress.
There are two satellite arrays carrying the COSPAS-SARSAT system. The principal array is
LEOSAR (Low Earth Orbit Search and Rescue) which has seven satellites in polar and near-
polar orbits. The orbits of these satellites are arranged to scan the entire surface of the Earth;
on average, a satellite comes into view every 45 minutes.
LEOSAR satellite path and scan footprint
Distress transmissions from EPIRBs are picked up by the satellites and retransmitted to
ground receiving stations, which then pass the message to the appropriate rescue organisation.
Typically, the delay from activation of an EPIRB to the message being received by the rescue
services is 45 minutes.
COSPAS-SARSAT is in an advanced stage of commissioning the second satellite array,
GEOSAR (Geostationary Search and Rescue). This array uses geostationary satellites which
are always in view (over their area of coverage), so that reception of the EPIRB signal is
instantaneous.
GEOSAR coverage
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