406 MHz BEACONS

 

Personal Locator Beacons were authorized for nationwide use beginning
July 1, 2003

 

There are three types of beacons used to transmit distress signals,
EPIRBs (for maritime use), ELTs (for aviation use), and PLBs
(used for land-based applications).

 

SEA 406 MHz EPIRB

This EPIRB has a high intensity xenon strobe light aid final location even in poor visibility.
 

Types of EPIRBs

Emergency position indicating radiobeacons (EPIRBs), devices which cost from $200 to about $1500, are designed to save your life if you get into trouble by alerting rescue authorities and indicating your location. EPIRB types are described below:

Class A
121.5/243 MHZ. Float-free, automatically-activating, detectable by aircraft and satellite. Coverage is limited. An alert from this device to a rescue coordination center may be delayed 4 - 6 or more hours. No longer recommended.

Class B
121.5/243 MHZ. Manually activated version of Class A. No longer recommended.

Class C

VHF ch15/16. Manually activated, operates on maritime channels only. Not detectable by satellite. These devices have been phased out by the FCC and are no longer recognized.

Class S

121.5/243 MHZ. Similar to Class B, except it floats, or is an integral part of a survival craft. No longer recommended.

Category I

406/121.5 MHZ. Float-free, automatically activated EPIRB. Detectable by satellite anywhere in the world. Recognized by GMDSS.

Category II
406/121.5 MHZ. Similar to Category I, except is manually activated. Some models are also water activated.

Inmarsat E

1646 MHZ. Float-free, automatically activated EPIRB. Detectable by Inmarsat geostationary satellite. Recognized by GMDSS. Currently not sold in the U.S.; however, the Federal Communications Commission is considering recognizing these devices.

121.5/243 MHz EPIRBs

These are the most common and least expensive type of EPIRB, designed to be detected by
overflying commercial or military aircraft. Satellites were designed to detect these EPIRBs, but are limited for the following reasons:

1.Satellite detection range is limited for these EPIRBs (satellites must be within line of sight of both the EPIRB and a ground terminal for detection to occur),

2.Frequency congestion in the band used by these devices cause a high satellite false alert rate (99.8%); consequently, confirmation is required before search and rescue forces can be deployed,

3.EPIRBs manufactured before October 1989 may have design or construction problems (e.g. some models will leak and cease operating when immersed in water), or may not be detectable by satellite. Such EPIRBs may no longer be sold,

4.Because of location ambiguities and frequency congestion in this band, two or more satellite passes are necessary to determine if the signal is from an EPIRB and to determine the location of the EPIRB, delaying rescue by an average of 4 to 6 hours. In some cases, a rescue can be delayed as long as 12 hours.

5.COSPAS-SARSAT is expected to cease detecting alerts on 121.5 MHz, perhaps by 2008.

One November 3, 2000, the National Oceanic and Atmospheric Administration (NOAA) announced that satellite processing 121.5/243 MHz emergency beacons will be terminated on February 1, 2009. Class A and B EPIRBs must be phased out by that date. The U.S. Coast Guard no longer recommends these EPIRBs be purchased. See the U.S. Coast Guard Media Advisory on this subject.

Class C EPIRBs

These are manually activated devices intended for pleasure craft which do not venture far offshore and for vessels on the Great Lakes. They transmit a short burst on VHF-FM channel 16 (156.8 MHz) and a longer homing signal on channel 15 (156.75 MHz). Their usefulness depended upon a coast station or another vessel guarding channel 16 and recognizing the brief, recurring tone as an EPIRB. Class C EPIRBs were not recognized outside of the United States, and were no longer recognized in the U.S. after 1999.

406 MHz EPIRBs

The 406 MHz EPIRB was designed to operate with satellites. The signal frequency (406 MHz) has been designated internationally for use only for distress. Other communications and interference, such as on 121.5 MHz, is not allowed on this frequency. Its signal allows a satellite local user terminal to accurately locate the EPIRB (much more accurately -- 2 to 5 km vice 25 km -- than 121.5/243 MHz devices), and identify the vessel (the signal is encoded with the vessel's identity) anywhere in the world (there is no range limitation). These devices are detectable not only by COSPAS-SARSAT satellites which are polar orbiting, but also by geostationary GOES weather satellites. EPIRBs detected by the GEOSTAR system, consisting of GOES and other geostationary satellites, send rescue authorities an instant alert, but without location information unless the EPIRB is equipped with an integral GPS receiver. EPIRBs detected by COSPAS-SARSAT (e.g. TIROS N) satellites provide rescue authorities location of distress, but location and sometimes alerting may be delayed as much as an hour or two. These EPIRBs also include a 121.5 MHz homing signal, allowing aircraft and rescue craft to quickly find the vessel in distress. These are the only type of EPIRB which must be certified by Coast Guard approved independent laboratories before they can be sold in the United States.

A new type of 406 MHz EPIRB, having an integral GPS navigation receiver, became available in 1998. This EPIRB will send accurate location as well as identification information to rescue authorities immediately upon activation through both geostationary (GEOSAR) and polar orbiting satellites. These types of EPIRB are the best you can buy.

406 MHz emergency locating transmitters (ELTs) for aircraft are currently available. 406 MHz personnel locating beacons (PLBs) are available in Alaska and Canada, and will soon be available throughout the U.S.

The Coast Guard recommends you purchase a 406 MHz EPIRB, preferably one with an integral GPS navigation receiver. A Cat I EPIRB should be purchased if it can be installed properly.

406 MHz GEOSAR System

The major advantage of the 406 MHz low earth orbit system is the provision of global Earth coverage using a limited number of polar-orbiting satellite. Coverage is not continuous, however, and it may take up to a couple of hours for an EPIRB alert to be received. To overcome this limitation, COSPAS-SARSAT has 406 MHz EPIRB repeaters aboard three geostationary satellites, plus one spare: GOES-W, at 135 deg W; GOES-E, at 75 deg W; INSAT-2A, at 74 deg E; and INSAT-2B (in-orbit spare), at 93.5 deg E. Ground stations capable of receiving 406 MHz. Except for areas between the United Kingdom and Norway, south of the east coast of Australia, and the area surrounding the Sea of Okhotsk near Russia, as well as polar areas, GEOSAR provides continuous global coverage of distress alerts from 406 MHz EPIRBs.

Note that GEOSAR cannot detect 121.5 MHz alerts, nor can it route unregistered 406 MHz alerts to a rescue authority. GEOSAR cannot calculate the location of any alert it receives, unless the beacon has an integral GPS receiver.
 

 

406 MHz Person Location BEACONS

 

PLBs are portable units that operate much the same as EPIRBs or ELTs. These beacons are designed to be carried by an individual person instead of on a boat or aircraft. Unlike ELTs and some EPIRBs, they can only be activated manually and operate exclusively on 406 MHz. And like EPIRBs and ELTs all PLBs also have a built-in, low-power homing beacon that transmits on 121.5 MHz. This allows rescue forces to home in on a beacon once the 406 MHz satellite system has gotten them "in the ballpark" (about 2-3 miles). Some newer PLBs also allow GPS units to be integrated into the distress signal. This GPS-encoded position dramatically improves the location accuracy down to the 100-meter level…that’s roughly the size of a football field.

Until July 1, 2003 only residents of Alaska can use PLBs. The Alaska PLB Program was set up to test the capabilities of PLBs and their potential impact on SAR resources during public usage. Since March of 1995, the experiment has proven very successful and has helped save nearly 400 lives while generating only a few false alerts. The success of the Alaska PLB program undoubtedly paved the way for nationwide usage of these devices.

Federal Agencies have also been using the PLB system for years. These agencies equip their agents who often work in remote or hostile environments and rely upon the Cospas-Sarsat system for immediate distress alerting capabilities.

When can I purchase and start using a PLB?
PLBs were authorized for use on July 1, 2003.

Where will the Personal Locator Beacons be sold?
Personal Locator Beacons will be sold in various outdoor supply stores, boating supply stores, electronics stores, and thru online and catalog distributors.

How much will they cost?
The PLBs will cost approximately $300 - $500 for lower end models. $1,200 to $1,800 for the higher end models. The higher end models will be GPS enhanced.

Will there be a penalty for an intentional false alert?
Under federal law, 14USC88, knowingly and willfully transmitting a hoax distress call is a felony. It is punishable by up to six years in prison, a $250,000 fine, and restitution to the rescue agency for all costs incurred responding to the distress.

If you purchase a new or a used 406 MHz EPIRB, ELT or PLB you MUST register it with NOAA. If you change your boat, your address, or your primary phone number, you MUST re-register your location beacon with NOAA. If you sell your beacon, make sure the purchaser re-registers the beacon, or you may be called by the Coast Guard (EPIRB), Civil Air Patrol (ELT) or local Search and Rescue team (PLB) if it later becomes activated.

Download or request 406 MHz EPIRB registration forms from, and mail or fax completed forms to:

SARSAT Beacon Registration
E/SP3, Rm 3320, FB-4
NOAA
5200 Auth Road
Suitland MD 20746-4304

or call toll free at 1-888-212-SAVE (i.e. 1-888-212-7283) for further information or a copy of the
registration form. From outside the U.S., call +1 (301) 457-5430 (fax: (301) 568-8649) for further
information. Forms may be requested by phone or fax, or downloaded by computer (above).
 

There is no charge for this service. IT MAY SAVE YOUR LIFE.

For more information see the NOAA SARSAT Homepage.