Programming

The perfect situation would be knowing who is transmitting an emergency signal (type of aircraft, colour of the fuselage, number of passengers, operator details...). It would enable  efficient organization of the Search & Rescue operation and provide an efficient solution to false alarms that plague the 121.5 MHz system.

But the digital message transmitted by the 406 MHz ELTs is too small to integrate this information. A 406 MHz message has only 112 (short message) or 144 bits (long message) among which only 60 bits are "useful". To overcome this problem, the required information is stored in a database addressed by the unique 15 HEX ID. The 15 digit HEX ID always contains the country code which determines the location of the database. The civil aviation authorities in the country of ELT registration which is not always the holder of the database determines the format of the 15 HEX ID (coding protocol). The precise structure of the 15 HEX ID can be viewed in COSPAS-SARSAT documents G.005 and T.001.

Four of the most commonly used protocols and therefore fully supported by Artex are:

 Aviation User - Tail Number (Short):  Identifies ELT by the Tail Number of the aircraft and country code, no position data is included in message

Serial User - Aircraft 24-Bit Address (Short): Identifies ELT by aircraft 24 bit address and country code, no position data is included in message

Aviation User-Location - Tail Number (Long): Identifies ELT by the Tail Number of the aircraft and country code, position data can be included in message (with C406-N ONLY) but it is limited to 4 minutes resolution (as per Cospas/Sarsat requirements)

Standard Location - ELT 24-Bit Address (Long): Identifies ELT by the 24-Bit Address of the aircraft and country code; the 24-Bit Address is also known as the "Mode-S" number, "octal number" or "ICAO Address" and is issued by a National Authority and is usually expressed as 8 octal digits or 6 hexadecimal digits. It can include position data (when using ELT w/ ELT/NAV Interface or a C406-N) with 4 seconds of resolution.

All ELTs are supplied pre-programmed ex factory, OEM or distributor.  

Re-programming of ELTs is available through Artex Certified Repair Stations and Level One Service Centers.

Information about application for becoming a Level One Service Center with programming capabilities is available only for FAR 145 and EASA 145 certified repair stations upon request from Artex management. Please send your contact request through the Contact Us page.