sensors Mode-S transponder

39C421

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HRBB · BOEING 787-9 Dreamliner

Hex
39C421
Octal
16342041
Decimal
3,785,761
Country
FR
Tail
F-HRBB
Type
B789
No current signal · last broadcast 1d ago
Flights observed
95
Distinct callsigns
20
Country
FR
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 39C421.

Country allocation

The ICAO 24-bit address 39C421 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 20 distinct

Callsign Airline Flights Last seen
AFR181 Air France 8 2026-05-19
AFR182 Air France 7 2026-05-18
AFR940 Air France 6 2026-04-26
AFR902 Air France 6 2026-04-29
AFR202 Air France 6 2026-05-23
AFR201 Air France 6 2026-05-24
AFR75K Air France 5 2026-05-25
AFR32J Air France 5 2026-05-21
AFR074 Air France 5 2026-05-25
AFR926 Air France 4 2026-04-27
AFR923 Air France 4 2026-04-28
AFR416 Air France 4 2026-05-12
AFR415 Air France 4 2026-05-12
AFR33J Air France 4 2026-05-22
AFR343 Air France 3 2026-05-09
AFR342T Air France 3 2026-05-09
AFR988 Air France 2 2026-04-23
AFR292 Air France 2 2026-05-22
AFR989 - 1 2026-04-23
AFR89U Air France 1 2026-05-12

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-28 AFR579 CKY → CDG May 28, 02:10 UTCMay 28, 07:10 UTC5h 0m
2026-05-27 AFR578 CDG → CKY May 27, 17:30 UTCMay 27, 22:40 UTC5h 10m
2026-05-25 AFR75K RDU → CDG May 25, 23:10 UTCMay 26, 06:14 UTC7h 5m
2026-05-25 AFR074 CDG → RDU May 25, 11:30 UTCMay 25, 19:30 UTC7h 59m
2026-05-24 AFR201 PEK → CDG May 24, 23:00 UTCMay 25, 03:35 UTC4h 35m
2026-05-24 AFR201 PEK → CDG May 24, 01:20 UTCMay 24, 23:46 UTC22h 26m
2026-05-23 AFR202 CDG → BOM May 23, 21:25 UTCMay 24, 01:40 UTC4h 15m
2026-05-23 AFR291 KIX → CDG May 23, 03:00 UTCMay 23, 17:05 UTC14h 5m
2026-05-22 AFR292 CDG → KIX May 22, 12:35 UTCMay 23, 00:50 UTC12h 15m
2026-05-22 AFR33J ATL → CDG May 22, 00:25 UTCMay 22, 08:15 UTC7h 50m
2026-05-21 AFR32J CDG → ATL May 21, 12:15 UTCMay 21, 21:15 UTC9h 0m
2026-05-20 AFR201 PEK → CDG May 20, 16:40 UTCMay 21, 04:15 UTC11h 35m
2026-05-20 AFR202 CDG → BOM May 20, 06:55 UTCMay 20, 07:10 UTC15m
2026-05-19 AFR202 CDG → BOM May 19, 21:00 UTCMay 20, 01:10 UTC4h 10m
2026-05-19 AFR181 SIN → CDG May 19, 03:20 UTCMay 19, 16:05 UTC12h 45m
2026-05-18 AFR182 CDG → SIN May 18, 12:05 UTCMay 19, 00:05 UTC11h 59m
2026-05-18 AFR33J ATL → CDG May 18, 00:50 UTCMay 18, 08:30 UTC7h 40m
2026-05-17 AFR32J CDG → ATL May 17, 12:25 UTCMay 17, 21:30 UTC9h 5m
2026-05-17 AFR33J ATL → CDG May 17, 00:30 UTCMay 17, 08:10 UTC7h 40m
2026-05-16 AFR32J CDG → ATL May 16, 18:15 UTCMay 16, 21:05 UTC2h 50m
2026-05-16 AFR32J CDG → ATL May 16, 12:16 UTCMay 16, 18:10 UTC5h 55m
2026-05-16 AFR33J ATL → CDG May 16, 00:25 UTCMay 16, 08:01 UTC7h 36m
2026-05-15 AFR32J CDG → ATL May 15, 12:15 UTCMay 15, 21:00 UTC8h 44m
2026-05-14 AFR75K RDU → CDG May 14, 22:25 UTCMay 15, 05:30 UTC7h 5m
2026-05-14 AFR074 CDG → RDU May 14, 11:55 UTCMay 14, 20:00 UTC8h 5m
2026-05-13 AFR75K RDU → CDG May 13, 22:25 UTCMay 14, 05:40 UTC7h 15m
2026-05-13 AFR074 CDG → RDU May 13, 11:35 UTCMay 13, 19:35 UTC8h 0m
2026-05-12 AFR415 FOR → CDG May 12, 22:55 UTCMay 13, 06:55 UTC8h 0m
2026-05-12 AFR416 CDG → FOR May 12, 12:00 UTCMay 12, 20:40 UTC8h 40m
2026-05-12 AFR89U MSP → CDG May 12, 02:45 UTCMay 12, 09:05 UTC6h 20m
2026-05-11 AFR088 CDG → SFO May 11, 14:25 UTCMay 11, 22:35 UTC8h 10m
2026-05-10 AFR415 FOR → CDG May 10, 23:05 UTCMay 11, 06:50 UTC7h 45m
2026-05-10 AFR416 CDG → FOR May 10, 12:30 UTCMay 10, 20:54 UTC8h 25m
2026-05-09 AFR343 YUL → CDG May 9, 21:19 UTCMay 10, 03:30 UTC6h 10m
2026-05-09 AFR342T CDG → YUL May 9, 09:20 UTCMay 9, 16:05 UTC6h 45m
2026-05-07 AFR343 YUL → CDG May 7, 21:25 UTCMay 8, 03:30 UTC6h 5m
2026-05-07 AFR342T CDG → YUL May 7, 08:50 UTCMay 7, 15:50 UTC7h 0m
2026-05-04 AFR291A KIX → CDG May 4, 12:00 UTCMay 5, 01:30 UTC13h 31m
2026-05-02 AFR292 CDG → KIX May 2, 12:20 UTCMay 3, 00:50 UTC12h 30m
2026-05-01 AFR75K RDU → CDG May 1, 22:30 UTCMay 2, 05:55 UTC7h 25m
2026-05-01 AFR074 CDG → RDU May 1, 11:40 UTCMay 1, 19:45 UTC8h 5m
2026-04-30 AFR327 YOW → CDG Apr 30, 21:25 UTCMay 1, 03:50 UTC6h 25m
2026-04-30 AFR328K CDG → YOW Apr 30, 11:45 UTCApr 30, 18:25 UTC6h 40m
2026-04-29 AFR902 CDG → NSI Apr 29, 22:30 UTCApr 30, 05:25 UTC6h 54m
2026-04-29 AFR902 CDG → NSI Apr 29, 20:10 UTCApr 29, 20:25 UTC15m
2026-04-29 AFR902 CDG → NSI Apr 29, 11:20 UTCApr 29, 12:55 UTC1h 35m
2026-04-28 AFR415 FOR → CDG Apr 28, 23:14 UTCApr 29, 07:15 UTC8h 0m
2026-04-28 AFR416 CDG → FOR Apr 28, 12:00 UTCApr 28, 20:40 UTC8h 40m
2026-04-28 AFR923 LBV → CDG Apr 28, 00:55 UTCApr 28, 03:25 UTC2h 30m
2026-04-27 AFR926 CDG → LBV Apr 27, 09:05 UTCApr 27, 15:45 UTC6h 40m

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

Mode-S 39C421 frequently asked

What is Mode-S code 39C421?
39C421 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HRBB.
Where is Mode-S 39C421 registered?
Mode-S code 39C421 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39C421 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 39C421, octal 16342041, decimal 3,785,761.
What flights does 39C421 operate?
Mode-S 39C421 has broadcast 20 distinct callsigns, including AFR181, AFR182, AFR940, AFR902, AFR202.