sensors Mode-S transponder

4ACA4A

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RRJ · BOEING 737-800

Hex
4ACA4A
Octal
22545112
Decimal
4,901,450
Country
SE
Tail
SE-RRJ
Type
B738
No current signal · last broadcast 6h ago
Flights observed
270
Distinct callsigns
20
Country
SE
Last broadcast
6h ago

Last known position

Most recent position reported by Mode-S 4ACA4A.

Country allocation

The ICAO 24-bit address 4ACA4A 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 20 distinct

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 NSZ24N NCE → ARN May 29, 19:15 UTCMay 29, 22:05 UTC2h 50m
2026-05-29 NSZ3YL ARN → NCE May 29, 15:35 UTCMay 29, 18:05 UTC2h 30m
2026-05-29 NSZ4CD LLA → ARN May 29, 12:20 UTCMay 29, 13:15 UTC55m
2026-05-29 NSZ39C ARN → LLA May 29, 10:30 UTCMay 29, 11:35 UTC1h 5m
2026-05-29 NSZ38K LLA → ARN May 29, 08:35 UTCMay 29, 09:35 UTC1h 0m
2026-05-29 NSZ35A ARN → LLA May 29, 06:50 UTCMay 29, 07:45 UTC55m
2026-05-29 NSZ3LW LLA → ARN May 29, 05:00 UTCMay 29, 05:55 UTC55m
2026-05-28 NSZ49H ARN → LLA May 28, 19:40 UTCMay 28, 20:40 UTC1h 0m
2026-05-28 NSZ46M LLA → ARN May 28, 17:50 UTCMay 28, 18:55 UTC1h 5m
2026-05-28 NSZ45F ARN → LLA May 28, 16:05 UTCMay 28, 17:05 UTC1h 0m
2026-05-28 NSZ44L LLA → ARN May 28, 14:10 UTCMay 28, 15:10 UTC1h 0m
2026-05-28 NSZ43E ARN → LLA May 28, 12:20 UTCMay 28, 13:15 UTC55m
2026-05-28 NSZ2MP NCE → ARN May 28, 08:45 UTCMay 28, 11:30 UTC2h 45m
2026-05-28 NSZ3YT ARN → NCE May 28, 05:00 UTCMay 28, 07:35 UTC2h 35m
2026-05-27 NSZ60X LGW → ARN May 27, 19:05 UTCMay 27, 21:10 UTC2h 5m
2026-05-27 NSZ59T ARN → LGW May 27, 15:30 UTCMay 27, 17:45 UTC2h 15m
2026-05-27 NSZ6LA LGW → ARN May 27, 12:15 UTCMay 27, 14:10 UTC1h 55m
2026-05-27 NSZ5WU ARN → LGW May 27, 08:55 UTCMay 27, 11:05 UTC2h 10m
2026-05-27 NSZ96Y CPH → ARN May 27, 07:00 UTCMay 27, 07:55 UTC55m
2026-05-27 NSZ5YB CPH → ARN May 27, 05:04 UTCMay 27, 05:59 UTC55m
2026-05-26 NSZ6MJ FAO → ARN May 26, 17:30 UTCMay 26, 21:25 UTC3h 55m
2026-05-26 NSZ75Z ARN → FAO May 26, 12:10 UTCMay 26, 16:30 UTC4h 20m
2026-05-26 NSZ38K LLA → ARN May 26, 08:30 UTCMay 26, 09:25 UTC55m
2026-05-26 NSZ35A ARN → LLA May 26, 06:44 UTCMay 26, 07:45 UTC1h 0m
2026-05-26 NSZ3LW LLA → ARN May 26, 04:39 UTCMay 26, 05:40 UTC1h 0m
2026-05-25 NSZ45F ARN → LLA May 25, 16:30 UTCMay 25, 17:30 UTC1h 0m
2026-05-25 NSZ44L LLA → ARN May 25, 14:20 UTCMay 25, 15:20 UTC1h 0m
2026-05-25 NSZ43E ARN → LLA May 25, 12:25 UTCMay 25, 13:25 UTC1h 0m
2026-05-25 NSZ2MP NCE → ARN May 25, 08:40 UTCMay 25, 11:20 UTC2h 40m
2026-05-25 NSZ3YT ARN → NCE May 25, 04:55 UTCMay 25, 07:30 UTC2h 35m
2026-05-24 NSZ60X LGW → ARN May 24, 19:40 UTCMay 24, 21:45 UTC2h 5m
2026-05-24 NSZ59T ARN → LGW May 24, 16:05 UTCMay 24, 18:35 UTC2h 30m
2026-05-24 NSZ4556 VNO → ARN May 24, 13:35 UTCMay 24, 14:50 UTC1h 15m
2026-05-24 NSZ4555 ARN → VNO May 24, 11:45 UTCMay 24, 12:45 UTC1h 0m
2026-05-24 NSZ2MP NCE → ARN May 24, 07:45 UTCMay 24, 10:30 UTC2h 45m
2026-05-24 NSZ3YT ARN → NCE May 24, 04:05 UTCMay 24, 06:35 UTC2h 30m
2026-05-23 NSZ4364 PMO → ARN May 23, 18:40 UTCMay 23, 21:55 UTC3h 15m
2026-05-23 NSZ4363 ARN → PMO May 23, 14:25 UTCMay 23, 17:25 UTC3h 0m
2026-05-23 NSZ4608 AYT → ARN May 23, 09:35 UTCMay 23, 13:25 UTC3h 50m
2026-05-23 NSZ4607 ARN → AYT May 23, 04:25 UTCMay 23, 08:00 UTC3h 35m
2026-05-22 NSZ4360 - May 22, 19:50 UTCMay 22, 22:45 UTC2h 55m
2026-05-22 NSZ4357 ARN → FCO May 22, 15:35 UTCMay 22, 18:10 UTC2h 35m
2026-05-22 NSZ4506 BER → ARN May 22, 11:45 UTCMay 22, 13:10 UTC1h 25m
2026-05-22 NSZ4505 ARN → BER May 22, 09:40 UTCMay 22, 10:50 UTC1h 10m
2026-05-22 NSZ8GH UME → ARN May 22, 08:10 UTCMay 22, 08:45 UTC35m
2026-05-22 NSZ8923 ALC → BCN May 22, 06:25 UTCMay 22, 07:05 UTC40m
2026-05-21 NSZ60X LGW → ARN May 21, 19:25 UTCMay 21, 21:25 UTC2h 0m
2026-05-21 NSZ59T ARN → LGW May 21, 15:55 UTCMay 21, 18:00 UTC2h 5m
2026-05-21 NSZ6LA LGW → ARN May 21, 12:25 UTCMay 21, 14:25 UTC2h 0m
2026-05-21 NSZ5WU ARN → LGW May 21, 09:00 UTCMay 21, 11:05 UTC2h 5m

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

Mode-S 4ACA4A frequently asked

What is Mode-S code 4ACA4A?
4ACA4A is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RRJ.
Where is Mode-S 4ACA4A registered?
Mode-S code 4ACA4A is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4ACA4A broadcasting right now?
No active broadcast right now. Last signal was 6h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4ACA4A, octal 22545112, decimal 4,901,450.
What flights does 4ACA4A operate?
Mode-S 4ACA4A has broadcast 20 distinct callsigns, including NSZ75Z, NSZ6MJ, NSZ3YT, NSZ38K, NSZ35A.