December 8, 2006
emergency location transmitters elts
SATELLITE PROCESSING OF 121.5/243 MHz EMERGENCY BEACONS
TO BE TERMINATED ON FEB. 1, 2009
The International Cospas-Sarsat Program, a program that uses a satellite
constellation to relay distress alerts to search and rescue authorities, announced at its
25th Council Session that it plans to terminate satellite processing of distress signals
from 121.5/243 MHz emergency beacons on Feb. 1, 2009. Mariners, aviators, and
individuals using emergency beacons will need to switch to those operating at 406 MHz
if they want to be detected by satellites.
The termination of 121.5/243 MHz processing is planned far enough into the
future to allow users adequate time for the transition to the 406 MHz beacon. The
Cospas-Sarsat Program has approved a plan for the phasing out of 121.5/243 MHz
satellite alerting services that address practical aspects of the phaseout. This decision
is a follow-on to Cospas-Sarsat’s announcement last year that it would no longer carry
121.5/243 MHz search and rescue instruments starting in 2006 for Russian satellites
and 2009 for the U.S. satellites, operated by the Commerce Department’s National
Oceanic and Atmospheric Administration.
The Cospas-Sarsat Program made the decision to terminate 121.5/243 MHz
satellite alerting services, in part, in response to guidance from the International
Maritime Organization and the International Civil Aviation Organization. These two
agencies of the United Nations are responsible for regulating the safety on international
transits of ships and aircraft, respectively, and handling international standards and
plans for maritime and aviation search and rescue. More than 180 nations are
members of IMO and ICAO.
- more -
Another major factor in the decision to stop satellite processing of 121.5/243 MHz
signals is due to problems in this frequency band which inundate search and rescue
authorities with false alerts, adversely impacting the effectiveness of lifesaving services.
Although the 406 MHz beacons cost more, they provide search and rescue agencies
with more reliable and complete information to do their job more efficiently and
effectively.
NOAA, along with the U.S. Coast Guard, U.S. Air Force and the National
Aeronautics and Space Administration, is responsible for implementing the Cospas-
Sarsat Program at the national level in the United States.
The implication of this Cospas-Sarsat decision is that users of beacons that send
distress alerts on 121.5 /243 MHz should eventually begin using beacons operating on
406 MHz if the alerts are to be detected and relayed via satellites. Meanwhile, anyone
planning to buy a new distress beacon may wish to take the Cospas-Sarsat decision
into account.
The three types of beacons in use are: emergency location transmitters (ELTs)
used on airplanes; emergency position indicating radio beacons (EPIRBs) , used on
boats; and personal locator beacons (PLBs) used by land-based persons such as
hikers.



