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sensors Mode-S transponder

399A4C

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HGSM · ROBIN DR-400

Hex
399A4C
Octal
16315114
Decimal
3,775,052
Country
FR
Tail
F-HGSM
Type
DR40
Broadcasting now · callsign FHGSM · 2,100 ft
Flights observed
63
Distinct callsigns
1
Country
FR
Last broadcast
1d ago

Current position

399A4C is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 399A4C falls within the block assigned to France (FR) by ICAO Annex 10, Volume III. Every aircraft registered in France receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 1 distinct

Callsign Airline Flights Last seen
FHGSM - 62 2026-07-18

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-18 FHGSM - Jul 18, 10:15 UTCJul 18, 10:55 UTC40m
2026-07-18 FHGSM - Jul 18, 08:05 UTCJul 18, 08:50 UTC45m
2026-07-17 FHGSM - Jul 17, 16:00 UTCJul 17, 16:15 UTC15m
2026-07-17 FHGSM - Jul 17, 09:04 UTCJul 17, 10:05 UTC1h 0m
2026-07-14 FHGSM - Jul 14, 17:25 UTCJul 14, 17:40 UTC15m
2026-07-14 FHGSM - Jul 14, 16:35 UTCJul 14, 16:55 UTC20m
2026-07-14 FHGSM - Jul 14, 08:15 UTCJul 14, 08:45 UTC30m
2026-07-14 FHGSM - Jul 14, 07:30 UTCJul 14, 07:40 UTC10m
2026-07-10 FHGSM - Jul 10, 07:40 UTCJul 10, 08:20 UTC40m
2026-07-09 FHGSM - Jul 9, 09:35 UTCJul 9, 09:50 UTC15m
2026-07-09 FHGSM - Jul 9, 08:10 UTCJul 9, 08:40 UTC30m
2026-07-08 FHGSM - Jul 8, 16:50 UTCJul 8, 17:15 UTC25m
2026-07-07 FHGSM - Jul 7, 08:50 UTCJul 7, 10:20 UTC1h 30m
2026-07-05 FHGSM - Jul 5, 15:40 UTCJul 5, 15:50 UTC10m
2026-07-05 FHGSM - Jul 5, 13:50 UTCJul 5, 14:00 UTC10m
2026-07-04 FHGSM - Jul 4, 13:45 UTCJul 4, 14:05 UTC20m
2026-07-04 FHGSM - Jul 4, 12:20 UTCJul 4, 12:55 UTC35m
2026-07-04 FHGSM - Jul 4, 07:55 UTCJul 4, 08:35 UTC40m
2026-07-03 FHGSM - Jul 3, 16:10 UTCJul 3, 16:40 UTC30m
2026-07-01 FHGSM - Jul 1, 13:45 UTCJul 1, 14:35 UTC50m
2026-06-27 FHGSM - Jun 27, 15:05 UTCJun 27, 15:24 UTC20m
2026-06-25 FHGSM - Jun 25, 07:30 UTCJun 25, 07:59 UTC30m
2026-06-21 FHGSM - Jun 21, 16:10 UTCJun 21, 16:25 UTC15m
2026-06-21 FHGSM - Jun 21, 14:05 UTCJun 21, 14:24 UTC20m
2026-06-20 FHGSM - Jun 20, 16:34 UTCJun 20, 17:04 UTC30m
2026-06-20 FHGSM - Jun 20, 15:34 UTCJun 20, 15:44 UTC10m
2026-06-14 FHGSM - Jun 14, 17:45 UTCJun 14, 18:10 UTC25m
2026-06-14 FHGSM - Jun 14, 13:40 UTCJun 14, 13:55 UTC15m
2026-06-12 FHGSM - Jun 12, 14:25 UTCJun 12, 14:40 UTC15m
2026-06-12 FHGSM - Jun 12, 13:10 UTCJun 12, 13:20 UTC10m
2026-05-31 FHGSM - May 31, 15:45 UTCMay 31, 17:05 UTC1h 20m
2026-05-31 FHGSM - May 31, 13:50 UTCMay 31, 14:05 UTC15m
2026-05-30 FHGSM - May 30, 14:45 UTCMay 30, 15:00 UTC15m
2026-05-30 FHGSM - May 30, 13:45 UTCMay 30, 14:05 UTC20m
2026-05-28 FHGSM - May 28, 17:35 UTCMay 28, 17:50 UTC15m
2026-05-26 FHGSM - May 26, 09:25 UTCMay 26, 09:45 UTC20m
2026-05-25 FHGSM - May 25, 16:50 UTCMay 25, 17:05 UTC15m
2026-05-25 FHGSM - May 25, 13:15 UTCMay 25, 14:00 UTC45m
2026-05-24 FHGSM - May 24, 16:30 UTCMay 24, 16:55 UTC25m
2026-05-23 FHGSM - May 23, 17:15 UTCMay 23, 19:45 UTC2h 31m
2026-05-23 FHGSM - May 23, 15:30 UTCMay 23, 15:45 UTC15m
2026-05-23 FHGSM - May 23, 14:20 UTCMay 23, 14:40 UTC20m
2026-05-23 FHGSM - May 23, 13:25 UTCMay 23, 13:40 UTC15m
2026-05-23 FHGSM - May 23, 09:45 UTCMay 23, 09:55 UTC10m
2026-05-22 FHGSM - May 22, 14:35 UTCMay 22, 14:50 UTC15m
2026-05-21 FHGSM - May 21, 15:10 UTCMay 21, 15:40 UTC30m
2026-05-15 FHGSM - May 15, 17:15 UTCMay 15, 17:40 UTC25m
2026-05-15 FHGSM - May 15, 15:40 UTCMay 15, 16:30 UTC50m
2026-05-08 FHGSM - May 8, 07:09 UTCMay 8, 07:55 UTC45m
2026-05-06 FHGSM - May 6, 18:00 UTCMay 6, 18:10 UTC10m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the F-HGSM page for operator, model, and routing details .

Mode-S 399A4C frequently asked

What is Mode-S code 399A4C?
399A4C is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HGSM.
Where is Mode-S 399A4C registered?
Mode-S code 399A4C is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 399A4C broadcasting right now?
Yes. Mode-S 399A4C is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 399A4C, octal 16315114, decimal 3,775,052.
What flights does 399A4C operate?
Mode-S 399A4C has broadcast 1 distinct callsign, including FHGSM.