Author: kevin

So far you have confirmed that your distress beacon will be used as a maritime Emergency Position Radio Indicating Beacon (EPIRB) and that it is a location protocol beacon. Three coding options have been developed for this type of beacon. However, your selection should be restricted to those protocols which have been authorised by your country’s competent authority on distress beacon matters (additional information concerning the authority / responsibility of States in respect of beacon message protocol selection is described at step 1 of this tutorial).

It should also be noted that the beacon message protocols which have been verified during the type approval testing are shown on the Cospas-Sarsat Type Approval Certificate issued by the Cospas-Sarsat Secretariat.

In view of the above, the selection of protocol should be further limited to those which have been type approved for use with the beacon model selected.

Having satisfied the two overriding criteria detailed above, the coding option to be selected depends on the information that you would like programmed into the beacon and its intended use. To proceed select the option that best suits your needs.

User Location Protocols: This option is formed by coding bits 1 through 106 of the EPIRB as a User Protocol, and providing the encoded location information to 4-minute resolution (approximately 6 miles or 10 kilometers) in the remaining bits. These protocols are only available in the long message format, and provide the lowest accuracy resolution of all long message format location protocols.

Standard Location Protocols: This option uniquely identifies the EPIRB using either:

• the vessels maritime mobile service identity number (MMSI); or
• a unique serial number allocated by either the competent national authority or the beacon manufacturer accompanied with the Cospas-Sarsat beacon type approval certificate number.

The Standard Location Protocols allow for location information of 4-second resolution to be encoded in the beacon message (approximately 120 meters). These protocols are only available in the long message format.

National Location Protocols: This option uses a unique serial number allocated by the competent national authority to uniquely identify the beacon. The National Location Protocols allow for location information of 4-second resolution to be encoded in the beacon message (approximately 120 meters). These protocols are only available in the long message format.

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EPIRBs can be divided into two categories: location protocol EPIRBs and non-location protocol EPIRBs.

A non-location protocol EPIRB does not have the capability to determine its own location, therefore, the distress position can only be determined by the Cospas-Sarsat System using Doppler location techniques. A short explanation of Cospas-Sarsat Doppler location principles is provided here.

A location protocol EPIRB is able to determine its own location, normally using an internal or external satellite navigation device (e.g. GPS), and transmit this location information in the beacon’s message. In addition, location protocol beacons will also be located by the Cospas-Sarsat System using Doppler location techniques.

An approved beacon model that is a location-protocol beacon will show a “Nav Device” available in its TAC Report, which can be viewed on the Professionals website (Pro/Beacons/Beacon Information/Approved Beacon Models (TACs)).

Click on the appropriate beacon category to proceed to Step 4:

• Location Protocol EPIRBs,
  
• Non-location Protocol EPIRBs.

For further details concerning beacons refer to the following documents (available for downloading):

• C/S G.005, Cospas-Sarsat Guidelines on 406 MHz Beacon Coding, Registration and Type Approval,
• C/S T.001, Specification for Cospas-Sarsat 406 MHz Distress Beacons.

Return to Beacon Coding Tutorial Flow Chart

You have selected the Serial User Protocol to be coded with the aircraft 24-bit address assigned by the competent national authority. An interactive diagram depicting the information which should be coded into the beacon is provided below. Click on the hyperlinked fields of the diagram for additional information concerning the format, structure and content of the coding for that field.

Final Step: Register your beacon.

Having purchased and coded your beacon, one of the most important actions that you must take to maximize its effectiveness is to register the beacon with the appropriate national authority.  Registering your beacon provides search and rescue authorities with access to vital information (e.g. telephone numbers for emergency points of contact, type of aircraft, etc.) that is absolutely critical for efficiently conducting any search and rescue operation.

For further details concerning beacons refer to the following documents (available for downloading):

• C/S T.001, Specification for Cospas-Sarsat 406 MHz Distress Beacons;
• C/S G.005, Cospas-Sarsat Guidelines on 406 MHz Beacon Coding, Registration and Type Approval.

You have selected the Serial User Protocol to be coded with the identification of the aircraft operator and a serial number. An interactive diagram depicting the information which should be coded into the beacon is provided below. Click on the hyperlinked fields of the diagram for additional information concerning the format, structure and content of the coding for that field.

Final Step: Register your beacon.

Having purchased and coded your beacon, one of the most important actions that you must take to maximize its effectiveness is to register the beacon with the appropriate national authority. Registering your beacon provides search and rescue authorities with access to vital information (e.g. telephone numbers for emergency points of contact, type of aircraft, etc.) that is absolutely critical for efficiently conducting any search and rescue operation.

For further details concerning beacons refer to the following documents (available for downloading):

• C/S T.001, Specification for Cospas-Sarsat 406 MHz Distress Beacons;
• C/S G.005, Cospas-Sarsat Guidelines on 406 MHz Beacon Coding, Registration and Type Approval.

You have selected the Serial User Protocol to be coded with a beacon serial number identification. An interactive diagram depicting the information which should be coded into the beacon is provided below. Click on the hyperlinked fields of the diagram for additional information concerning the format, structure and content of the coding for that field.

Final Step: Register your beacon.

Having purchased and coded your beacon, one of the most important actions that you must take to maximize its effectiveness is to register the beacon with the appropriate national authority. Registering your beacon provides search and rescue authorities with access to vital information (e.g. telephone numbers for emergency points of contact, type of aircraft, etc.) that is absolutely critical for efficiently conducting any search and rescue operation.

For further details concerning beacons refer to the following documents (available for downloading):

• C/S T.001, Specification for Cospas-Sarsat 406 MHz Distress Beacons;
• C/S G.005, Cospas-Sarsat Guidelines on 406 MHz Beacon Coding, Registration and Type Approval.

So far you have confirmed that your distress beacon will be used as an aviation Emergency Locator Transmitter (ELT) and that it is a non-location protocol beacon. Four coding options have been developed for this type of beacon. However, your selection should be restricted to those protocols that have been authorised by your country’s competent authority on distress beacon matters (additional information concerning the authority/responsibility of States in respect of beacon message protocol selection is described at step 1 of this tutorial). From the protocols approved for use by your country’s designated authority on distress beacon matters, the option to be selected depends on the information that you would like programmed into the beacon and its intended use. To proceed select the option that best suits your needs.

Serial User Protocol Coded with a Unique Beacon Serial Number: This option uses a serial number, allocated by either the competent national authority or the beacon manufacturer, to uniquely identify the beacon. A feature of this protocol is that it does not include information which directly identifies the aircraft in which it is installed, consequently, the ELT can be moved to another aircraft without necessarily requiring recoding. When this protocol is used, SAR services are 100% dependent upon beacon registration for obtaining any information concerning the aircraft or the operator of the beacon. Therefore, it is essential to ensure that the beacon is properly registered and that registration information is updated if the registration information changes or the beacon is moved to a different aircraft.

Serial User Protocol Coded with the Aircraft Operator Designator & a Serial Number: This protocol was designed for use by operators of fleet(s) of aircraft (e.g. airlines). This option uniquely identifies the beacon using a combination of :

• an aircraft operator designator code defined in accordance with International Civil Aviation Organization (ICAO) DOC 8585, accompanied by
• a serial number between 1 and 4096 assigned by the operator.

Since the beacon code identifies the operator, subject to national regulations, the operator will be able to change ELTs amongst its fleet, provided that the operator establishes a 24-hour point of contact available to SAR services for informing SAR personnel of which ELT is on which aircraft.

Serial User Protocol Coded with the Aircraft 24-Bit Address: This option uses the unique 24-bit binary aircraft identification code assigned by National Administrations to encode the beacon identification. The format for the 24-bit code is described in Annex 10 to the Convention on International Civil Aviation. This code can only be used if your country assigns a 24-bit designator to your aircraft.

Aviation User Protocol Coded with the Aircraft Nationality and Registration Marking: This option uses the unique alphanumeric aircraft registration marking assigned by National Administrations to code the beacon identification. The format for this designator is provided in Annex 10 to the Convention on International Civil Aviation.

Note: The Convention on International Civil Aviation requires all 406 MHz ELTs to be registered with the appropriate national authorities.

Return to Beacon Coding Tutorial Flow Chart

So far you have confirmed that your distress beacon will be used as an aviation Emergency Locator Transmitter (ELT) and that it is a location protocol beacon. Three coding options have been developed for this type of beacon. However, your selection should be restricted to those protocols that have been authorised by your country’s competent authority on distress beacon matters (additional information concerning the authority/responsibility of States in respect of beacon message protocol selection is described at step 1 of this tutorial).

It should also be noted that the beacon message protocols that have been verified during the type-approval testing are shown on the Cospas-Sarsat Type Approval Certificate issued by the Cospas-Sarsat Secretariat.

In view of the above, the selection of protocol should be further limited to those that have been type approved for use with the beacon model selected.

Having satisfied the two overriding criteria detailed above, the coding option to be selected depends on the information that you would like programmed into the beacon and its intended use. To proceed, select the option that best suits your needs.

User Location Protocols: This option is formed by coding bits 1 through 106 of the ELT as a User Protocol, and providing the encoded location information to 4-minute resolution (approximately 6 miles or 10 kilometers) in the remaining bits. These protocols are only available in the long message format, and provide the lowest accuracy resolution of all long message format location protocols.

Standard Location Protocols: This option uniquely identifies the ELT using either:

• the 24-bit binary aircraft identification assigned by National Administrations,
• a unique serial number allocated by either the competent national authority or the beacon manufacturer accompanied by the Cospas-Sarsat beacon type approval certificate number, or
• the Aircraft Operator designator and a serial number.

The Standard Location Protocols allow for location information of 4-second resolution to be encoded in the beacon message (approximately 120 meters). These protocols are only available in the long message format.

National Location Protocols: This option uses a unique serial number allocated by the competent national authority to uniquely identify the beacon. The National Location Protocols allow for location information of 4-second resolution to be encoded in the beacon message (approximately 120 meters). These protocols are only available in the long message format.

Return to Beacon Coding Tutorial Flow Chart

ELTs can be divided into two categories: location protocol ELTs and non-location protocol ELTs.

A non-location protocol ELT does not have the capability to determine its own location, therefore, the distress position can only be determined by the Cospas-Sarsat System using Doppler location techniques.

A location protocol ELT is able to determine its own location, normally using an internal or external satellite navigation device (e.g. GPS), and transmit this location information in the beacon’s message. In addition, location protocol beacons will also be located by the Cospas-Sarsat System using Doppler location techniques.

An approved beacon model that is a location-protocol beacon will show a “Nav Device” available in its TAC Report, which can be viewed on the Professionals website (Pro/Beacons/Beacon Information/Approved Beacon Models (TACs)).

Click on the appropriate beacon category to proceed to Step 4:

• Location Protocol ELTs;
• Non-location Protocol ELTs.

For further details concerning beacons refer to the following documents (available for downloading):

• C/S G.005, Cospas-Sarsat Guidelines on 406 MHz Beacon Coding, Registration and Type Approval,
• C/S T.001, Specification for Cospas-Sarsat 406 MHz Distress Beacons.

Return to Beacon Coding Tutorial Flow Chart

There are many different beacon message protocols available. However, different protocols are defined for specific types of distress beacons. For example, a given protocol may be authorised for use with beacons installed on aircraft, but should not be used for beacons installed on maritime vessels.

The choice of protocols is narrowed by the type of beacon to be coded. Select the type of beacon from the list below to proceed to step 3:

• ELT – Emergency Locator Transmitter designed for installation on aircraft;
• EPIRB – Emergency Position Indicating Radio Beacon designed for installation on maritime vessels;
• PLB – Personal Locator Beacon designed to be carried by a person.

Although it does not impact upon the selection of a beacon message protocol, beacon types can be further subdivided by their method of activation. In the aviation domain there are automatic and manual ELTs. Automatic ELTs are designed to be activated automatically using a crash sensor or G-switch, whereas manual ELTs can only be activated by the ELT operator. Similarly, in the maritime domain there are float free and non-float free beacons. Float-free beacons are designed to float away from a sinking vessel and activate automatically, whereas non-float-free beacons are activated manually.

Later in the tutorial a detailed explanation of all beacon message protocols will be provided.

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