sensors Mode-S transponder

4AC9E1

ICAO 24-bit transponder address · allocated to Sweden

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

Hex
4AC9E1
Octal
22544741
Decimal
4,901,345
Country
SE
Tail
SE-ROA
Type
A20N
Photo of SE-ROA
No current signal · last broadcast 17h ago
Flights observed
13
Distinct callsigns
8
Country
SE
Last broadcast
17h ago

Last known position

Most recent position reported by Mode-S 4AC9E1.

Country allocation

The ICAO 24-bit address 4AC9E1 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 8 distinct

Callsign Airline Flights Last seen
SAS51H - 3 2026-04-13
SAS751 Scandinavian Airlines System 2 2026-04-14
SAS52R Scandinavian Airlines System 2 2026-04-14
SAS1874 Scandinavian Airlines System 2 2026-04-13
SAS85J - 1 2026-04-13
SAS767 - 1 2026-04-13
SAS676 - 1 2026-04-13
SAS1879 - 1 2026-04-13

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-14 SAS52R WAW → CPH Apr 14, 09:10 UTCApr 14, 09:45 UTC35m
2026-04-14 SAS52R WAW → CPH Apr 14, 08:35 UTCApr 14, 09:05 UTC30m
2026-04-14 SAS751 CPH → WAW Apr 14, 07:10 UTCApr 14, 07:45 UTC35m
2026-04-14 SAS751 CPH → WAW Apr 14, 06:45 UTCApr 14, 07:10 UTC25m
2026-04-13 SAS1879 - Apr 13, 17:35 UTCApr 13, 18:25 UTC50m
2026-04-13 SAS1874 CPH → SVG Apr 13, 16:15 UTCApr 13, 16:35 UTC20m
2026-04-13 SAS1874 CPH → SVG Apr 13, 15:55 UTCApr 13, 16:15 UTC20m
2026-04-13 SAS676 - Apr 13, 13:45 UTCApr 13, 14:50 UTC1h 5m
2026-04-13 SAS51H - Apr 13, 12:20 UTCApr 13, 12:35 UTC15m
2026-04-13 SAS51H - Apr 13, 11:55 UTCApr 13, 12:35 UTC40m
2026-04-13 SAS51H - Apr 13, 11:15 UTCApr 13, 12:15 UTC1h 0m
2026-04-13 SAS85J - Apr 13, 08:35 UTCApr 13, 09:45 UTC1h 10m
2026-04-13 SAS767 CPH → PRG Apr 13, 06:30 UTCApr 13, 07:40 UTC1h 10m

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

Mode-S 4AC9E1 frequently asked

What is Mode-S code 4AC9E1?
4AC9E1 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-ROA.
Where is Mode-S 4AC9E1 registered?
Mode-S code 4AC9E1 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4AC9E1 broadcasting right now?
No active broadcast right now. Last signal was 17h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4AC9E1, octal 22544741, decimal 4,901,345.
What flights does 4AC9E1 operate?
Mode-S 4AC9E1 has broadcast 8 distinct callsigns, including SAS51H, SAS751, SAS52R, SAS1874, SAS85J.