Apparatus

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sensors Mode-S transponder

3991A3

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HEND · CESSNA 510 Citation Mustang

Hex
3991A3
Octal
16310643
Decimal
3,772,835
Country
FR
Tail
F-HEND
Type
C510
No current signal · last broadcast Jul 26, 08:20 UTC
Flights observed
101
Distinct callsigns
20
Country
FR
Last broadcast
Jul 26, 08:20 UTC

Last known position

Most recent position reported by Mode-S 3991A3.

Country allocation

The ICAO 24-bit address 3991A3 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
FHEND - 9 2026-06-19
IXR543 - 5 2026-07-10
IXR135 - 5 2026-04-25
IXR883 - 4 2026-05-25
IXR911 - 3 2026-04-24
IXR781 - 3 2026-06-19
IXR761 - 3 2026-06-18
IXR706 - 3 2026-07-24
IXR617 - 3 2026-06-14
IXR435 - 3 2026-07-21
IXR434 - 3 2026-07-19
IXR330 - 3 2026-07-26
IXR257 - 3 2026-05-12
IXR159 - 3 2026-05-31
IXR022 - 3 2026-07-15
IXR924 - 2 2026-07-17
IXR920 - 2 2026-06-25
IXR902 - 2 2026-06-11
IXR901 - 2 2026-06-07
IXR871 - 2 2026-05-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 IXR330 - Jul 26, 07:05 UTCJul 26, 08:20 UTC1h 15m
2026-07-25 IXR330 - Jul 25, 15:20 UTCJul 25, 17:05 UTC1h 45m
2026-07-24 IXR330 - Jul 24, 14:30 UTCJul 24, 16:40 UTC2h 10m
2026-07-24 IXR706 - Jul 24, 13:00 UTCJul 24, 13:40 UTC40m
2026-07-23 IXR706 - Jul 23, 09:15 UTCJul 23, 09:55 UTC40m
2026-07-23 IXR706 - Jul 23, 07:35 UTCJul 23, 07:45 UTC10m
2026-07-21 IXR435 - Jul 21, 15:35 UTCJul 21, 16:15 UTC40m
2026-07-21 IXR435 RNS → TLS Jul 21, 13:40 UTCJul 21, 14:45 UTC1h 5m
2026-07-21 IXR435 - Jul 21, 11:35 UTCJul 21, 12:25 UTC50m
2026-07-19 IXR434 BSL → LBG Jul 19, 15:00 UTCJul 19, 16:00 UTC1h 0m
2026-07-19 IXR434 - Jul 19, 11:55 UTCJul 19, 13:15 UTC1h 20m
2026-07-18 IXR434 - Jul 18, 09:45 UTCJul 18, 10:45 UTC1h 0m
2026-07-17 IXR924 - Jul 17, 09:45 UTCJul 17, 10:40 UTC55m
2026-07-17 IXR924 - Jul 17, 08:10 UTCJul 17, 08:59 UTC50m
2026-07-15 IXR022 - Jul 15, 17:20 UTCJul 15, 18:20 UTC1h 0m
2026-07-15 IXR022 - Jul 15, 14:35 UTCJul 15, 15:55 UTC1h 20m
2026-07-15 IXR022 - Jul 15, 11:20 UTCJul 15, 13:20 UTC2h 0m
2026-07-10 IXR543 NCE → LBG Jul 10, 14:35 UTCJul 10, 16:10 UTC1h 35m
2026-07-09 IXR543 - Jul 9, 17:30 UTCJul 9, 19:35 UTC2h 5m
2026-07-09 IXR543 - Jul 9, 15:20 UTCJul 9, 16:15 UTC55m
2026-07-05 IXR279 BRS → LBG Jul 5, 16:50 UTCJul 5, 17:50 UTC1h 0m
2026-07-05 IXR279 - Jul 5, 14:15 UTCJul 5, 15:25 UTC1h 10m
2026-07-04 IXR662 - Jul 4, 11:55 UTCJul 4, 12:55 UTC1h 0m
2026-07-04 IXR662 LBG → GVA Jul 4, 09:45 UTCJul 4, 10:40 UTC55m
2026-07-03 IXR324 STR → LBG Jul 3, 15:35 UTCJul 3, 16:40 UTC1h 5m
2026-07-03 IXR324 - Jul 3, 06:20 UTCJul 3, 07:25 UTC1h 5m
2026-06-25 IXR920 - Jun 25, 15:20 UTCJun 25, 15:44 UTC25m
2026-06-25 IXR920 - Jun 25, 13:29 UTCJun 25, 14:09 UTC40m
2026-06-25 IXR381 - Jun 25, 09:45 UTCJun 25, 10:39 UTC55m
2026-06-20 IXR341 - Jun 20, 20:34 UTCJun 20, 20:45 UTC10m
2026-06-20 IXR341 - Jun 20, 18:49 UTCJun 20, 19:40 UTC50m
2026-06-19 FHEND FAB → LBG Jun 19, 14:24 UTCJun 19, 15:29 UTC1h 5m
2026-06-19 IXR781 - Jun 19, 12:09 UTCJun 19, 13:04 UTC55m
2026-06-19 IXR781 - Jun 19, 08:04 UTCJun 19, 08:59 UTC55m
2026-06-19 IXR781 - Jun 19, 06:10 UTCJun 19, 07:04 UTC55m
2026-06-18 IXR761 - Jun 18, 16:50 UTCJun 18, 17:55 UTC1h 5m
2026-06-18 IXR761 - Jun 18, 14:20 UTCJun 18, 15:55 UTC1h 35m
2026-06-16 IXR761 - Jun 16, 06:45 UTCJun 16, 08:35 UTC1h 50m
2026-06-16 FHEND - Jun 16, 05:10 UTCJun 16, 05:34 UTC25m
2026-06-14 IXR617 MXP → LBG Jun 14, 19:30 UTCJun 14, 20:50 UTC1h 20m
2026-06-14 IXR617 - Jun 14, 16:30 UTCJun 14, 18:00 UTC1h 30m
2026-06-14 IXR617 - Jun 14, 12:00 UTCJun 14, 12:40 UTC40m
2026-06-13 FHEND - Jun 13, 09:50 UTCJun 13, 11:25 UTC1h 35m
2026-06-12 IXR616 - Jun 12, 09:00 UTCJun 12, 10:10 UTC1h 10m
2026-06-12 IXR616 - Jun 12, 07:10 UTCJun 12, 07:45 UTC35m
2026-06-11 IXR902 - Jun 11, 16:10 UTCJun 11, 17:55 UTC1h 45m
2026-06-11 IXR902 - Jun 11, 11:35 UTCJun 11, 11:50 UTC15m
2026-06-11 IXR923 - Jun 11, 08:55 UTCJun 11, 10:00 UTC1h 5m
2026-06-08 IXR543 TLS → LBG Jun 8, 15:10 UTCJun 8, 16:35 UTC1h 25m
2026-06-08 IXR543 - Jun 8, 13:00 UTCJun 8, 13:50 UTC50m

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

Mode-S 3991A3 frequently asked

What is Mode-S code 3991A3?
3991A3 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HEND.
Where is Mode-S 3991A3 registered?
Mode-S code 3991A3 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3991A3 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 08:20 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3991A3, octal 16310643, decimal 3,772,835.
What flights does 3991A3 operate?
Mode-S 3991A3 has broadcast 20 distinct callsigns, including FHEND, IXR543, IXR135, IXR883, IXR911.