sensors Mode-S transponder

4AC9B4

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RMT · BOMBARDIER BD-700 Global 6000/6500

Hex
4AC9B4
Octal
22544664
Decimal
4,901,300
Country
SE
Tail
SE-RMT
Type
GLEX
No current signal · last broadcast 21h ago
Flights observed
49
Distinct callsigns
1
Country
SE
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S 4AC9B4.

Country allocation

The ICAO 24-bit address 4AC9B4 falls within the block assigned to Sweden (SE) by ICAO Annex 10, Volume III. Every aircraft registered in Sweden 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
SERMT - 49 2026-05-29

Recent flights last 49

DateFlightRouteTakeoffLandingDuration
2026-05-29 SERMT LPI → LPI May 29, 09:55 UTCMay 29, 10:20 UTC25m
2026-05-29 SERMT - May 29, 09:35 UTCMay 29, 09:50 UTC15m
2026-05-29 SERMT - May 29, 09:10 UTCMay 29, 09:30 UTC20m
2026-05-29 SERMT LPI → LPI May 29, 08:45 UTCMay 29, 09:00 UTC15m
2026-05-28 SERMT - May 28, 09:35 UTCMay 28, 10:10 UTC35m
2026-05-28 SERMT LPI → LPI May 28, 09:10 UTCMay 28, 09:25 UTC15m
2026-05-28 SERMT LPI → LPI May 28, 08:45 UTCMay 28, 09:05 UTC20m
2026-05-25 SERMT - May 25, 12:20 UTCMay 25, 12:40 UTC20m
2026-05-25 SERMT - May 25, 12:00 UTCMay 25, 12:15 UTC15m
2026-05-25 SERMT - May 25, 11:25 UTCMay 25, 11:55 UTC30m
2026-05-25 SERMT LPI → LPI May 25, 10:40 UTCMay 25, 11:20 UTC40m
2026-05-22 SERMT - May 22, 05:55 UTCMay 22, 16:00 UTC10h 5m
2026-05-22 SERMT - May 22, 04:15 UTCMay 22, 04:25 UTC10m
2026-05-20 SERMT - May 20, 19:30 UTCMay 21, 05:25 UTC9h 55m
2026-05-20 SERMT - May 20, 16:10 UTCMay 20, 18:20 UTC2h 10m
2026-05-13 SERMT - May 13, 09:15 UTCMay 13, 10:10 UTC55m
2026-05-13 SERMT - May 13, 08:25 UTCMay 13, 08:40 UTC15m
2026-05-12 SERMT - May 12, 08:15 UTCMay 12, 10:10 UTC1h 55m
2026-05-11 SERMT - May 11, 08:05 UTCMay 11, 09:20 UTC1h 15m
2026-05-07 SERMT BMA → LPI May 7, 15:05 UTCMay 7, 15:30 UTC25m
2026-05-07 SERMT - May 7, 13:40 UTCMay 7, 14:20 UTC40m
2026-05-07 SERMT BMA → GOT May 7, 10:10 UTCMay 7, 10:55 UTC45m
2026-05-05 SERMT - May 5, 15:10 UTCMay 5, 15:55 UTC45m
2026-05-05 SERMT - May 5, 11:15 UTCMay 5, 11:40 UTC25m
2026-05-05 SERMT - May 5, 05:15 UTCMay 5, 05:50 UTC35m
2026-05-04 SERMT - May 4, 09:40 UTCMay 4, 10:05 UTC25m
2026-05-04 SERMT - May 4, 05:20 UTCMay 4, 05:45 UTC25m
2026-05-03 SERMT - May 3, 14:50 UTCMay 3, 15:10 UTC20m
2026-04-30 SERMT LPI → LPI Apr 30, 11:05 UTCApr 30, 11:40 UTC35m
2026-04-30 SERMT BMA → LPI Apr 30, 07:25 UTCApr 30, 07:50 UTC25m
2026-04-29 SERMT - Apr 29, 16:00 UTCApr 29, 19:45 UTC3h 45m
2026-04-27 SERMT BMA → CAT Apr 27, 14:10 UTCApr 27, 17:55 UTC3h 45m
2026-04-27 SERMT - Apr 27, 12:25 UTCApr 27, 12:50 UTC25m
2026-04-22 SERMT - Apr 22, 18:20 UTCApr 22, 18:45 UTC25m
2026-04-22 SERMT OBF → BMA Apr 22, 15:55 UTCApr 22, 17:50 UTC1h 55m
2026-04-21 SERMT BMA → OBF Apr 21, 13:40 UTCApr 21, 15:20 UTC1h 40m
2026-04-21 SERMT - Apr 21, 12:10 UTCApr 21, 12:35 UTC25m
2026-04-20 SERMT - Apr 20, 09:30 UTCApr 20, 11:05 UTC1h 35m
2026-04-17 SERMT - Apr 17, 17:25 UTCApr 17, 17:40 UTC15m
2026-04-17 SERMT - Apr 17, 15:20 UTCApr 17, 16:35 UTC1h 15m
2026-04-17 SERMT - Apr 17, 14:40 UTCApr 17, 15:15 UTC34m
2026-04-17 SERMT - Apr 17, 05:20 UTCApr 17, 07:15 UTC1h 55m
2026-04-16 SERMT - Apr 16, 15:30 UTCApr 16, 15:55 UTC25m
2026-04-16 SERMT - Apr 16, 10:05 UTCApr 16, 10:49 UTC45m
2026-04-16 SERMT - Apr 16, 09:24 UTCApr 16, 09:54 UTC30m
2026-04-13 SERMT ARN → LPI Apr 13, 05:40 UTCApr 13, 06:05 UTC25m
2026-04-13 SERMT - Apr 13, 04:20 UTCApr 13, 04:25 UTC5m
2026-04-13 SERMT - Apr 13, 03:55 UTCApr 13, 04:25 UTC30m
2026-04-13 SERMT - Apr 13, 01:35 UTCApr 13, 04:15 UTC2h 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 SE-RMT page for operator, model, and routing details .

Mode-S 4AC9B4 frequently asked

What is Mode-S code 4AC9B4?
4AC9B4 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RMT.
Where is Mode-S 4AC9B4 registered?
Mode-S code 4AC9B4 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4AC9B4 broadcasting right now?
No active broadcast right now. Last signal was 21h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4AC9B4, octal 22544664, decimal 4,901,300.
What flights does 4AC9B4 operate?
Mode-S 4AC9B4 has broadcast 1 distinct callsign, including SERMT.