sensors Mode-S transponder

3851E4

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-BUPE · ROBIN DR-400

Hex
3851E4
Octal
16050744
Decimal
3,690,980
Country
FR
Tail
F-BUPE
Type
DR40
No current signal · last broadcast 6d ago
Flights observed
38
Distinct callsigns
1
Country
FR
Last broadcast
6d ago

Last known position

Most recent position reported by Mode-S 3851E4.

Country allocation

The ICAO 24-bit address 3851E4 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
FBUPE - 38 2026-05-28

Recent flights last 38

DateFlightRouteTakeoffLandingDuration
2026-05-28 FBUPE - May 28, 13:10 UTCMay 28, 13:20 UTC10m
2026-05-26 FBUPE - May 26, 15:35 UTCMay 26, 16:35 UTC1h 0m
2026-05-26 FBUPE - May 26, 13:40 UTCMay 26, 14:00 UTC20m
2026-05-26 FBUPE - May 26, 12:20 UTCMay 26, 12:45 UTC25m
2026-05-26 FBUPE - May 26, 08:04 UTCMay 26, 08:19 UTC15m
2026-05-25 FBUPE - May 25, 15:50 UTCMay 25, 17:00 UTC1h 10m
2026-05-24 FBUPE - May 24, 17:40 UTCMay 24, 17:55 UTC15m
2026-05-23 FBUPE - May 23, 17:40 UTCMay 23, 17:50 UTC10m
2026-05-23 FBUPE - May 23, 08:25 UTCMay 23, 08:55 UTC30m
2026-05-22 FBUPE - May 22, 14:55 UTCMay 22, 15:05 UTC10m
2026-05-22 FBUPE - May 22, 13:35 UTCMay 22, 14:00 UTC25m
2026-05-22 FBUPE - May 22, 09:10 UTCMay 22, 09:35 UTC25m
2026-05-21 FBUPE - May 21, 18:00 UTCMay 21, 18:45 UTC45m
2026-05-19 FBUPE - May 19, 09:20 UTCMay 19, 09:30 UTC10m
2026-05-17 FBUPE - May 17, 14:35 UTCMay 17, 14:55 UTC20m
2026-05-17 FBUPE - May 17, 13:31 UTCMay 17, 13:55 UTC25m
2026-05-16 FBUPE - May 16, 15:10 UTCMay 16, 15:31 UTC20m
2026-05-16 FBUPE - May 16, 14:11 UTCMay 16, 14:20 UTC10m
2026-05-15 FBUPE - May 15, 10:50 UTCMay 15, 11:00 UTC10m
2026-05-13 FBUPE - May 13, 14:35 UTCMay 13, 14:45 UTC10m
2026-05-09 FBUPE - May 9, 15:10 UTCMay 9, 16:30 UTC1h 20m
2026-05-09 FBUPE - May 9, 07:25 UTCMay 9, 08:45 UTC1h 20m
2026-05-08 FBUPE - May 8, 15:25 UTCMay 8, 15:55 UTC30m
2026-04-28 FBUPE - Apr 28, 17:05 UTCApr 28, 17:15 UTC10m
2026-04-28 FBUPE - Apr 28, 09:50 UTCApr 28, 10:05 UTC15m
2026-04-26 FBUPE - Apr 26, 09:20 UTCApr 26, 09:30 UTC10m
2026-04-25 FBUPE - Apr 25, 09:35 UTCApr 25, 10:00 UTC25m
2026-04-24 FBUPE - Apr 24, 17:10 UTCApr 24, 17:40 UTC30m
2026-04-23 FBUPE - Apr 23, 17:45 UTCApr 23, 18:45 UTC1h 0m
2026-04-23 FBUPE - Apr 23, 11:20 UTCApr 23, 11:40 UTC20m
2026-04-22 FBUPE - Apr 22, 17:10 UTCApr 22, 17:40 UTC30m
2026-04-22 FBUPE - Apr 22, 12:15 UTCApr 22, 12:50 UTC35m
2026-04-20 FBUPE - Apr 20, 09:40 UTCApr 20, 10:20 UTC40m
2026-04-19 FBUPE - Apr 19, 13:45 UTCApr 19, 14:55 UTC1h 10m
2026-04-19 FBUPE - Apr 19, 08:30 UTCApr 19, 09:45 UTC1h 15m
2026-04-17 FBUPE - Apr 17, 17:35 UTCApr 17, 17:50 UTC15m
2026-04-17 FBUPE - Apr 17, 16:00 UTCApr 17, 16:20 UTC20m
2026-04-17 FBUPE - Apr 17, 13:55 UTCApr 17, 14:40 UTC45m

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-BUPE page for operator, model, and routing details .

Mode-S 3851E4 frequently asked

What is Mode-S code 3851E4?
3851E4 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-BUPE.
Where is Mode-S 3851E4 registered?
Mode-S code 3851E4 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3851E4 broadcasting right now?
No active broadcast right now. Last signal was 6d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3851E4, octal 16050744, decimal 3,690,980.
What flights does 3851E4 operate?
Mode-S 3851E4 has broadcast 1 distinct callsign, including FBUPE.