sensors Mode-S transponder

4AC9F9

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-ROY · AIRBUS A-320neo

Hex
4AC9F9
Octal
22544771
Decimal
4,901,369
Country
SE
Tail
SE-ROY
Type
A20N
Photo of SE-ROY
No current signal · last broadcast 13h ago
Flights observed
11
Distinct callsigns
7
Country
SE
Last broadcast
13h ago

Last known position

Most recent position reported by Mode-S 4AC9F9.

Country allocation

The ICAO 24-bit address 4AC9F9 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 7 distinct

Callsign Airline Flights Last seen
SAS4637 Scandinavian Airlines System 3 2026-04-14
SAS53D - 2 2026-04-13
SAS4497 - 2 2026-04-13
SAS804 - 1 2026-04-13
SAS4496 - 1 2026-04-13
SAS4433 - 1 2026-04-12
SAS4430 Scandinavian Airlines System 1 2026-04-12

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-14 SAS4637 OSL → ATH Apr 14, 09:10 UTCApr 14, 09:55 UTC45m
2026-04-14 SAS4637 OSL → ATH Apr 14, 07:10 UTCApr 14, 09:05 UTC1h 55m
2026-04-14 SAS4637 OSL → ATH Apr 14, 06:20 UTCApr 14, 07:10 UTC50m
2026-04-13 SAS4497 - Apr 13, 19:50 UTCApr 13, 20:30 UTC40m
2026-04-13 SAS4497 - Apr 13, 18:55 UTCApr 13, 20:10 UTC1h 15m
2026-04-13 SAS4496 - Apr 13, 14:10 UTCApr 13, 15:30 UTC1h 20m
2026-04-13 SAS804 LHR → OSL Apr 13, 09:50 UTCApr 13, 11:25 UTC1h 35m
2026-04-13 SAS53D - Apr 13, 07:55 UTCApr 13, 08:15 UTC20m
2026-04-13 SAS53D OSL → LHR Apr 13, 06:15 UTCApr 13, 08:15 UTC2h 0m
2026-04-12 SAS4433 - Apr 12, 19:05 UTCApr 12, 20:15 UTC1h 10m
2026-04-12 SAS4430 OSL → TOS Apr 12, 17:15 UTCApr 12, 18:00 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 SE-ROY page for operator, model, and routing details .

Mode-S 4AC9F9 frequently asked

What is Mode-S code 4AC9F9?
4AC9F9 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-ROY.
Where is Mode-S 4AC9F9 registered?
Mode-S code 4AC9F9 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4AC9F9 broadcasting right now?
No active broadcast right now. Last signal was 13h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4AC9F9, octal 22544771, decimal 4,901,369.
What flights does 4AC9F9 operate?
Mode-S 4AC9F9 has broadcast 7 distinct callsigns, including SAS4637, SAS53D, SAS4497, SAS804, SAS4496.