What Is An ELT ???

             elt110-4.gif (12900 bytes)                  capplane.gif (30327 bytes)


Only You Can Prevent False Alarms.

           The Federal Aviation Administration requires that all aircraft have on board an ELT before they can be registered or authorized for flight. An ELT is designed to emit an audible radio signal on various radio frequencies if it experiences a certain amount of G forces. Activating a switch, a low battery and other phenomena may also cause an ELT to transmit its siren type tone. Once an ELT has been activated, a COPAS/SARSAT satellite receives the signal and it is sent to the Air Force Rescue and Coordination Center's LUTs. (Local User Terminals). Their are currently 35 LUTs in operation world wide with several more built or planned this year. The closest LUT to South Carolina is in Houston, Texas at NASA's Johnson Space Flight Center. If the ELT is close enough, it's signal can also be heard inside a control tower at an airport.

         Any time an ELT signal is transmitted, everyone must proceed as if there has been an accident or crash and lives may be in the balance. For this reason, time is of the utmost importance. After a couple of SARSAT "hits" the AFRCC can pinpoint the latitude and longitude within 25 square miles.   The AFRCC will then assign an ELT mission number to the closest Civil Air Patrol unit for ELT deactivation. CAP aircraft and ground teams are dispatched to locate and disarm the unit.

        CAP aircrews and groundteams use ELT direction finding (DF) receivers, such

as  "The Tracker" tracker.jpg (11518 bytes)or "Little L-Per " ( L-Tronics, 5546 Cathedral Oaks Road, Santa Barbara, CA 93111  Tel: 805-967-4859   e-mail  bgordon@rain.org ) to locate ELT and EPIRB signals with pinpoint accuracy.  An EPIRB (Emergency Position Indicating Radio Beacons ) is for maritime (boats & ships) use. Click here to see picture of the system operation.                                      

If you would like more information about ELTs and EPIRBs (Emergency Position Indicating Radio Beacons), try the following links:

ELT System Operation

NASA Goddard Space Flight Center SAR Mission Office

NASA Copa-Sarsat System

COPAS/SARSAT Emergency Beacons


AFRCC (Air Force Rescue Coordination Center)

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