User Manual

Y1-03-0343 Rev. B Company Confidential
7
Anatomy of a Rescue
How the Beacon Works
How your beacon summons help:
406 MHz beacons are a type of portable
emergency equipment that transmits a distress
signal to search and rescue (SAR)
organizations. The purpose of these beacons is to
aid SAR teams in tracking and locating ships or
individuals in jeopardy as rapidly as possible.
The 406 MHz frequency is a worldwide dedicated emergency frequency that is detected by a
network of satellites called the Cospas-Sarsat system. This satellite system was established by,
and continues to be supported by, its primary
benefactors – the USA, Russia, Canada and
France. The Cospas-Sarsat system has saved
tens of thousands of lives, and counting, since
its inception.
When a 406 MHz beacon is activated, the digital distress message is sent to Cospas-Sarsat
satellites and, in turn, the distress message is relayed to SAR forces via a Rescue Coordination
Centre (RCC). The distress message contains the beacon UIN and on some models, the GPS
location of the beacon. Additional information about the beacon is accessed by SAR forces from
the beacon registration database. At the same time the 406 MHz signal is activated, a 121.5
MHz signal is turned on. The 121.5 MHz signal is used by SAR forces to home in on the beacon
as they approach it.
The 406 MHz signal is detected by multiple satellites and from that information the location of
the beacon can be calculated. This data alone is sufficient for SAR to find persons or ships in
distress in a reasonable timeframe. However, as a further enhancement, some beacons have a
GPS engine on board (all ACR PLB’s currently manufactured include a GPS engine on board).
This feature allows the beacon to acquire current location coordinates from an internal GPS
receiver. The purpose of this feature is to send an even more precise location of the beacon to
the satellites (i.e., latitude and longitude data). This helps SAR to reach the location even
faster.
International customers should visit
www.406registration.com
and view the Beacon Registration Contacts List to find the
proper location to register your beacon.
Learn more about the Cospas-Sarsat
satellite system: www.cospas-sarsat.org