How Do I Select and Purchase a 406-MHz Cospas-Sarsat Beacon?


Beacons are manufactured, marketed and sold competitively by several different companies through a variety of vendor chains. 

Cospas-Sarsat (working with the manufacturer and independent laboratories) rigorously tests and “type approves” beacon models before they go into production to ensure that production beacons sold to the public can be expected to operate under a variety of extreme conditions.

The International Cospas-Sarsat Programme does not itself manufacture, market or sell beacons. A list of manufacturers is available at our Professionals website under "Contact Lists" (Pro).

The first consideration in selecting a beacon is the type of environment in which you expect to use it. A 406-MHz beacon designed for use in an aircraft is known as an Emergency Locator Transmitter (ELT).[1] One designed for use aboard a marine vessel is called an Emergency Position-Indicating Radio Beacon (EPIRB). And one that is designed to be carried by an individual (such as while hiking/trekking) is known as a Personal Locator Beacon (PLB). Sometimes PLBs are carried aboard aircraft or vessels, but you must check with local authorities about the circumstances under which this is permitted.

Beacons have different features for activation in an emergency. Most beacons can be activated manually by a person pressing a button. Most ELTs are designed to be activated automatically by a physical shock, such as in a crash, and most EPIRBs are designed to be automatically activated by contact with water. Some EPIRBs are designed to be held in a bracket outside of the vessel such that it will “float free” and activate automatically if the vessel sinks. PLBs usually have only a manual activation capability. There are many variations of activation and deployment features for beacons to suit many, many different situations and needs, so you should evaluate these features carefully.

During type-approval testing, beacon models are evaluated to one of two temperature extremes: -40 degrees Celsius (which receives a Class 1 type approval) and -20 degrees Celsius (which receives a Class 2 type approval).

Many beacon models not only transmit a distress message on 406 MHz for satellite reception, they also transmit a lower powered signal on 121.5 MHz as a reference for local search teams to “home” in on the signal once they arrive near the location calculated for the beacon. In some countries such a “homing transmitter” is a mandatory beacon feature.

Although the Cospas-Sarsat System is designed to independently locate activated distress beacons with good accuracy, many beacons now also are equipped with an integrated receiver chip for the beacon to determine its own location using signals from global navigation satellite systems (GNSS), such as GPS, GLONASS or GALILEO. If the integrated receiver chip is able to calculate a location for the beacon, that location is reported in the distress message transmitted from the beacon. GNSS-equipped beacons provide helpful redundancy in determining the beacon location and in certain circumstances can reduce the time needed for Cospas-Sarsat to locate the beacon.

Some aviation ELTs and marine EPIRBs may have an interface that allows the beacon to have location data reported to it by the avionics or marine electronics so that the information is continuously updated, stored and available to be transmitted if the beacon is activated.

A list of type-approved beacon models with some details about model features is available on our Professionals website under "Approved Beacon Models" (Pro/Beacons/Beacon Information).

A few beacons, with exceptional characteristics, may not meet all of the standards for type-approval, but still may be approved for use with Cospas-Sarsat by virtue of a “letter of compatibility”. Such beacons may be perfectly suitable for your particular needs, but you will need to take extra care to be certain that is the case.

While Cospas-Sarsat (working with the manufacturer and independent laboratories) rigorously tests and “type approves” beacon models before they go into production to ensure that production beacons sold to the public can be expected to operate under a variety of extreme conditions, Cospas-Sarsat type approval alone does NOT qualify the beacon for sale or use in any particular country, nor determine whether the beacon satisfies local and international regulatory requirements regarding aircraft and vessels. You must check with your local authorities about the number and types of beacons that may be required on your aircraft or vessel. Some of this information may be found in the “Beacon Regulations Handbook” (Pro/Beacons/Beacon Information).

If your aircraft/vessel makes international voyages, you may be subject to specific requirements established by the International Civil Aviation Organization (e.g., Annex 6, Part 1 of the ICAO Convention) or the International Maritime Organization (e.g., Chapter IV of the IMO’s Convention on Safety of Life at Sea).

Beacon manufacturers establish their own marketing and retailing chains. Aviation ELTs usually can be purchased at aviation equipment supply stores or service facilities. Similarly, marine EPIRBs usually can be purchased at marine supply stores or service facilities. PLBs usually can be purchased at sporting-goods and outdoor-goods stores. Beacons of all types can be purchased from vendors on the internet. Please note that if you purchase a beacon from a vendor in a country different from the one where your aircraft/vessel is flagged, or different from your country of residence, in order to successfully register the beacon you may need to have the “country code” that has been electronically encoded in the beacon reprogrammed to a new (your current) country code by an authorized service facility at an additional cost.


[1] Some ELTs (often older models) transmit only a legacy analogue signal on 121.5 MHz or 243 MHz. Cospas-Sarsat does NOT monitor those frequencies and such beacons rely on being received only by nearby aircraft or rescue personnel. For satellite reception of alerts by Cospas-Sarsat the beacon must be a model that transmits at 406 MHz.