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sensors Mode-S transponder

3951E8

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-GUPI · ROBIN DR-400

Hex
3951E8
Octal
16250750
Decimal
3,756,520
Country
FR
Tail
F-GUPI
Type
DR40
No current signal · last broadcast 3d ago
Flights observed
53
Distinct callsigns
1
Country
FR
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S 3951E8.

Country allocation

The ICAO 24-bit address 3951E8 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
FGUPI - 53 2026-07-17

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-17 FGUPI - Jul 17, 08:30 UTCJul 17, 09:20 UTC50m
2026-07-15 FGUPI - Jul 15, 07:30 UTCJul 15, 09:20 UTC1h 50m
2026-07-13 FGUPI - Jul 13, 06:35 UTCJul 13, 07:40 UTC1h 5m
2026-07-12 FGUPI - Jul 12, 07:40 UTCJul 12, 08:25 UTC45m
2026-07-11 FGUPI - Jul 11, 07:15 UTCJul 11, 08:05 UTC50m
2026-07-10 FGUPI - Jul 10, 06:50 UTCJul 10, 07:05 UTC15m
2026-07-09 FGUPI - Jul 9, 09:05 UTCJul 9, 09:50 UTC45m
2026-07-09 FGUPI GAT → VAF Jul 9, 07:35 UTCJul 9, 08:15 UTC40m
2026-07-09 FGUPI - Jul 9, 07:00 UTCJul 9, 07:15 UTC15m
2026-07-07 FGUPI - Jul 7, 09:25 UTCJul 7, 10:05 UTC40m
2026-07-07 FGUPI - Jul 7, 07:30 UTCJul 7, 08:45 UTC1h 15m
2026-07-06 FGUPI - Jul 6, 07:15 UTCJul 6, 08:35 UTC1h 20m
2026-07-04 FGUPI - Jul 4, 06:45 UTCJul 4, 06:55 UTC10m
2026-07-03 FGUPI - Jul 3, 07:35 UTCJul 3, 07:50 UTC15m
2026-06-26 FGUPI - Jun 26, 08:50 UTCJun 26, 09:35 UTC45m
2026-06-26 FGUPI - Jun 26, 07:35 UTCJun 26, 07:55 UTC20m
2026-06-23 FGUPI - Jun 23, 07:25 UTCJun 23, 09:09 UTC1h 45m
2026-06-21 FGUPI - Jun 21, 06:50 UTCJun 21, 07:00 UTC10m
2026-06-19 FGUPI - Jun 19, 07:29 UTCJun 19, 07:45 UTC15m
2026-06-16 FGUPI - Jun 16, 08:35 UTCJun 16, 09:55 UTC1h 20m
2026-06-14 FGUPI - Jun 14, 11:15 UTCJun 14, 11:55 UTC40m
2026-06-14 FGUPI - Jun 14, 08:20 UTCJun 14, 08:35 UTC15m
2026-06-14 FGUPI - Jun 14, 07:35 UTCJun 14, 07:50 UTC15m
2026-06-12 FGUPI - Jun 12, 09:00 UTCJun 12, 10:05 UTC1h 5m
2026-06-12 FGUPI - Jun 12, 07:25 UTCJun 12, 07:35 UTC10m
2026-06-07 FGUPI - Jun 7, 09:05 UTCJun 7, 09:50 UTC45m
2026-05-31 FGUPI - May 31, 14:30 UTCMay 31, 16:15 UTC1h 45m
2026-05-30 FGUPI - May 30, 08:50 UTCMay 30, 09:15 UTC25m
2026-05-30 FGUPI - May 30, 04:55 UTCMay 30, 06:15 UTC1h 20m
2026-05-26 FGUPI - May 26, 14:00 UTCMay 26, 14:50 UTC50m
2026-05-25 FGUPI - May 25, 07:30 UTCMay 25, 08:20 UTC50m
2026-05-23 FGUPI - May 23, 07:45 UTCMay 23, 08:25 UTC40m
2026-05-18 FGUPI - May 18, 10:15 UTCMay 18, 11:00 UTC45m
2026-05-18 FGUPI - May 18, 08:45 UTCMay 18, 09:35 UTC50m
2026-05-17 FGUPI - May 17, 14:40 UTCMay 17, 15:10 UTC30m
2026-05-17 FGUPI - May 17, 10:50 UTCMay 17, 11:20 UTC30m
2026-05-17 FGUPI - May 17, 08:55 UTCMay 17, 09:45 UTC50m
2026-05-13 FGUPI - May 13, 06:45 UTCMay 13, 07:00 UTC15m
2026-05-01 FGUPI - May 1, 12:55 UTCMay 1, 13:30 UTC35m
2026-05-01 FGUPI - May 1, 09:05 UTCMay 1, 09:20 UTC15m
2026-04-28 FGUPI - Apr 28, 08:40 UTCApr 28, 08:50 UTC10m
2026-04-28 FGUPI - Apr 28, 07:40 UTCApr 28, 07:55 UTC15m
2026-04-27 FGUPI - Apr 27, 12:55 UTCApr 27, 13:30 UTC35m
2026-04-27 FGUPI - Apr 27, 09:35 UTCApr 27, 10:30 UTC55m
2026-04-26 FGUPI - Apr 26, 07:50 UTCApr 26, 08:25 UTC35m
2026-04-25 FGUPI - Apr 25, 17:05 UTCApr 25, 17:25 UTC20m
2026-04-25 FGUPI - Apr 25, 16:10 UTCApr 25, 16:25 UTC15m
2026-04-25 FGUPI - Apr 25, 07:45 UTCApr 25, 08:40 UTC55m
2026-04-21 FGUPI - Apr 21, 08:55 UTCApr 21, 09:20 UTC25m
2026-04-21 FGUPI - Apr 21, 07:15 UTCApr 21, 07:25 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-GUPI page for operator, model, and routing details .

Mode-S 3951E8 frequently asked

What is Mode-S code 3951E8?
3951E8 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-GUPI.
Where is Mode-S 3951E8 registered?
Mode-S code 3951E8 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3951E8 broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3951E8, octal 16250750, decimal 3,756,520.
What flights does 3951E8 operate?
Mode-S 3951E8 has broadcast 1 distinct callsign, including FGUPI.