FLARM: Update now, recode if necessary, and test

“As numerous investigations into collisions, near-misses and dangerous encounters over the last ten years or so show, the risk of a mid-air collision (MAC) when flying under visual flight rules (VFR) in class G and E airspaces is real and probably greater than often assumed,” concluded the Swiss Transportation Safety Investigation Board (STSB) regarding a tragic accident in the Swiss mountains. The following comment can also be read in one of the last accident reports: “A new Flarm was installed in HB-xxxx and the ID was probably not updated in the OGN. However, the exact take-off time makes it possible to assign the ID.”

Sense and avoid: A look at OGN shows a need for action
Since “see and avoid” is often supplemented by technical collision avoidance aids such as FLARM these days, the software update, as well as the configuration and any recoding, is extremely important. This is because an avoidance maneuver can only take place if other aircraft are detected by a FLARM in time and perceived by the pilot. A daily glance at Open Glider Network (OGN) reveals this. Unfortunately, there are regularly aircraft that are detected but cannot be unambiguously assigned due to a missing reprogramming/update. In most cases, the A/C registration is not correctly coded in the FLARM, as can be seen in the two gliders in the picture below.

Figure: Screenshot from Safe Sky ( ) and date [PDB1]

Annual inspection for FLARM: Update, coding and test of transmission power
Technical aids such as FLARM are only useful if they are correctly installed and maintained to ensure their functionality. This includes, in particular, software and database updates as well as regular transmission power tests. Therefore, the following three steps must be carried out at least once a year:

Firmware update
FLARM uses a rolling update process that requires an annual update. It is best to carry out the update during the annual aircraft inspection. This ensures that not only the airworthiness requirements of the aircraft but also those of the FLARM are met. All information about FLARM devices can be found on the FLARM website

Ideal for general aviation – FLARM and the latest software releases as well as all downloads for FLARM devices are available in the Documents, Manuals and Firmware – FLARM section.

Correct coding with 24 ICAO Bit Code
To ensure that your aircraft is also visible to other airspace users, the FLARM should be optimally coded. This step is particularly important after initial installation, a cockpit conversion or a change of owner. Otherwise, the aircraft’s identification is not visible in OGN and only the FLARM number is displayed, which is useless in SAR operations. It is therefore very important that the FLARM device is configured correctly. With the FLARM configuration tool, a configuration file can be created quickly and easily and sent to itself by email. The final step is to program the FLARM using the instructions in Optimal FLARM setup (segelflug.ch). For aircraft with a transponder on board, it is mandatory to overwrite the FLARM ID with the 24-bit ICAO hex address of the aircraft and to enter or register the ICAO hex address on the glider net (OGN Devices Database (glidernet.org) [PDB2]

Test the FLARM transmission power (range analysis)
Finally, the transmission and reception power of the FLARM must be checked. With the help of the Range Analysis – FLARM tool, problems with a FLARM installation can be detected and corrected in good time to ensure that the collision warning devices have good mutual visibility.

Safety first, every flight, every time.

#flightpreparation #avsafety #generalaviation #pilots