Most of you probably already know that starting in February 2009, over-the-air television broadcasts will be going digital in the United States. This means that if you want to continue to receive free television reception, you must have a newer TV that has a digital tuner or you need to get a digital-to-analog converter box.
But, did you know that there is a critical piece of life-saving equipment that will also be affected with a change from analog to digital transmissions?
If you own or use an emergency distress beacon on a boat or on a plane, you should know that starting on February 1, 2009, the older beacons that transmit only an analog signal (121.5 or 243 MHz) will no longer be “heard” by search and rescue satellites. Just like checking your TV, you need to ensure that your distress beacon is capable of transmitting a digital signal (406 MHz) in order for it to be recognized.
There are three types of emergency distress beacons: EPIRBs (Emergency Positioning Indicating Radio Beacons) for use in the maritime community, ELTs (Emergency Locator Transmitters) found on aircraft and PLBs (Personal Locator Beacons) for individual use. Although PLBs have always been manufactured to transmit to satellites on the 406 MHz frequency, older models of EPIRBs and ELTs were made to transmit to satellites on the 121.5 and 243 MHz frequencies. It should be noted that all 406 MHz beacons in the U.S. also contain a low powered homing signal that transmits on 121.5 MHz. This signal doesn’t reach the satellites, but it allows search and rescue teams to home-in on the beacon once in close range.
The decision to stop satellite processing of the 121.5 and 243 MHz frequency bands was made by the International Cospas-Sarsat Program with guidance from the United Nations. 406 MHz distress beacons have been used successfully for over 15 years now and they have proven to be more powerful, more accurate, and they are verifiable. Because of the digital nature of 406 MHz beacons, every beacon in the world has a unique ID encoded in its signal. As long as the beacon is registered (which is required by U.S. law), search and rescue forces can quickly confirm that the distress is real and have access to important information about the beacon owner.
When a person in distress activates an EPIRB, ELT or PLB (or an EPIRB automatically activates when a vessel sinks or an ELT automatically activates when an aircraft crashes), a signal is transmitted to search and rescue satellites. This “alert” is then relayed to a network of ground stations on Earth. If the signal originates in the U.S. the alert is sent to the U.S. Mission Control Center (USMCC) operated by NOAA. The USMCC processes the alert then distributes it to a U.S. Coast Guard or U.S. Air Force Rescue Coordination Center depending on if the location is in a maritime or inland environment. In the past five years (2003-2007), 406 MHz beacons have directly contributed to the saving of 1,224 lives in the U.S. alone.
Mariners should know that 121.5 MHz EPIRBs became prohibited for use in January 2007.
Aircraft owners and operators should be aware that, although 121.5 or 243 MHz ELTs still meet FAA carriage requirements, the distress signal will not be automatically sent to search and rescue personnel. The only way an alert will be realized is if a radio in close proximity to the beacon is tuned to the 121.5 or 243 MHz frequency and the operator passes the alert information to proper authorities. Even if this takes place, without the amplifying information provided by 406 MHz beacons, the results of a successful search are greatly diminished. That being said, pilots and other aviation interests should increase their attention to monitoring the 121.5 MHz frequency any time they have the chance to do so.
If you decide to replace an old 121.5 MHz EPIRB or ELT, please make sure you disable it by removing and properly disposing of the batteries. Also, remember to register your 406 MHz beacon at www.beaconregistration.noaa.gov. Registration is free, easy to do and mandatory. You can include and update important information anytime such as emergency contact numbers, a description of your boat or aircraft, a person’s medical condition, or even a simplified float or flight plan—anything to make it easier for us to find you!
All beacon owners and users should check their beacons (just like those TV sets) before the switch to digital takes place in February 2009. Your life may well depend on it!
This information is provided by the U.S. Coast Guard Office of Search and Rescue (CG-534).