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FLARM live range analyzer and SAR info

Please enter your 6 digit Radio ID (FLARM/OGN tracker, ICAO ID etc.) below to obtain a range and SAR report.


OGN station health monitoring

Please enter your OGN station name to obtain its health status.

OGN station name:

Please check the FAQ below to learn how the analyzer operates and which regions are supported.

Fleet reports

Please contact us if you'd like to add your club's fleet here!

Resetting your report

We recommend to reset and re-evaluate your report if there was any major change to your aircraft or FLARM installation (e.g., FLARM device or antenna change, configuration change, major avionics update, etc.)

To reset, please send us email indicating your FLARM ID.


Notice that XX0001 was only seen from one station, so its bad range may also be an artefact due to the station. For a meaningful result, you should show on 3 stations at least.


How does this work?

The live analyzer uses signal strength data from ground receiver stations of the Open Glider Network (OGN).

How do I get a meaningful report for my FLARM?

For best results, fly for at least an hour within 50km of at least three different OGN stations. The stations will receive your FLARM and measure its signal strength.

Only data of aircraft moving with at least 5 m/s are considered.

Where are the OGN stations?

Germany, France and the UK very well covered. A map of OGN stations together with coverage information is available here.

What is my FLARM ID and how do I find it?

The FLARM ID consists of six hexadecimal digits is unique to your FLARM device. It may be automatically selected by FLARM or set to the ICAO code of your aircraft. You can find it in IGC files created by your FLARM. Look for the following entry near the top of any IGC file using a text editor:

HFPRSPressAltSensor:MEAS MS5540
LFLA135559ID 2 DE050F

How long do you retain the data?

Data are accumulated for at least 28 days.

How often should I check my report?

We recommend to check your report once per year as part of annual maintenance, and additionally if:

How does this compare to the FLARM online range analyzer?

The live analyzer shows the transmit performance whereas the range analyzer available from FLARM evaluates the receive performance (the sensitivity). Both are often similar, but not necessarily the same.

What do the plots show?

The first plot shows the average signal strength (in dB) of your FLARM over distance in meters. The green line represents the average of a large sample of FLARM devices.

The second plot shows the average distance your FLARM is received with a signal strength of less than 10dB (blue) and from 10 to 20dB (red). Data are averaged over sectors of 30 degrees relative to your aircraft. In the plot, the nose of the aircraft points UP. The X and Y axes are in meters. The distance is computed in three dimensions, but projected to 2D for plotting. (We may do a side view in the future if there is enough interest and we find the time!).

How should my plot look like?

Please look at the examples above.

Why do I get position jumps and "possible duplicate" on the ID?

A position jump is counted if the GPS reports reliable position but the aircraft moves faster than physically possible. Possible reasons include a duplicate device ID, misconfigured OGN stations and indeed unreliable GPSs. We flag a possible duplicate if more than 8 jumps are detected.

In order to investigate the nature of the problem, it's best to reset the report and look at your aircraft live or at flight traces in glidertracker or live.glidernet.org. If you see a 'shadow aircraft' moving in parallel somewhere else, the reason is a misconfigured station. If there are frequent uncorrelated jumps, another aircraft with the same ID (hence duplicate) is flying at the same time.

Notice that misconfigured station clocks can also cause trigger the jump detection.

How often are the data processed?

All data are processed continuously in realtime. You can evaluate your report immediately after the flight.

What about the new 'Do Not Track' flag in FLARM (April 2015)?

The live range analyzer cannot process data of FLARMs which have the 'Do Not Track'-flag set. If your device shows up despite the flag being set, please do contact us and attach your FLARM configuration file.

Data sources: OGN, openAIP, KTrax REST API • By using this site, you agree to our Terms and Conditions and Privacy Policy