Apparatus

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sensors Mode-S transponder

4ACA81

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RTA · BOEING 737 MAX 8

Hex
4ACA81
Octal
22545201
Decimal
4,901,505
Country
SE
Tail
SE-RTA
Type
B38M
No current signal · last broadcast 8h ago
Flights observed
225
Distinct callsigns
20
Country
SE
Last broadcast
8h ago

Last known position

Most recent position reported by Mode-S 4ACA81.

Country allocation

The ICAO 24-bit address 4ACA81 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

Callsign Airline Flights Last seen
NSZ2616 Norwegian Air Sweden AOC 7 2026-05-03
NSZ8YC Norwegian Air Sweden AOC 5 2026-05-03
NSZ6RD Norwegian Air Sweden AOC 5 2026-05-22
NSZ2TH Norwegian Air Sweden AOC 5 2026-05-03
NSZ2913 Norwegian Air Sweden AOC 5 2026-05-20
NSZ2767 Norwegian Air Sweden AOC 5 2026-05-21
NSZ2766 Norwegian Air Sweden AOC 5 2026-05-21
NSZ2613 Norwegian Air Sweden AOC 5 2026-05-18
NSZ9WP Norwegian Air Sweden AOC 4 2026-05-20
NSZ6HT Norwegian Air Sweden AOC 4 2026-05-21
NSZ2901 Norwegian Air Sweden AOC 4 2026-05-08
NSZ2900 Norwegian Air Sweden AOC 4 2026-05-08
NSZ2845 Norwegian Air Sweden AOC 4 2026-05-20
NSZ2844 Norwegian Air Sweden AOC 4 2026-05-20
NSZ2621 Norwegian Air Sweden AOC 4 2026-05-22
NSZ2620 Norwegian Air Sweden AOC 4 2026-05-22
NSZ2617 Norwegian Air Sweden AOC 4 2026-04-26
NSZ2615 Norwegian Air Sweden AOC 4 2026-04-28
NSZ2614 Norwegian Air Sweden AOC 4 2026-04-28
NSZ6LA Norwegian Air Sweden AOC 3 2026-05-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 NSZ4508 BER → ARN May 29, 19:35 UTCMay 29, 21:00 UTC1h 25m
2026-05-29 NSZ4507 ARN → BER May 29, 17:00 UTCMay 29, 18:15 UTC1h 15m
2026-05-29 NSZ4EM EDI → ARN May 29, 14:10 UTCMay 29, 15:55 UTC1h 45m
2026-05-29 NSZ3BM ARN → EDI May 29, 11:10 UTCMay 29, 13:10 UTC2h 0m
2026-05-29 NSZ48U BUD → ARN May 29, 08:05 UTCMay 29, 10:05 UTC2h 0m
2026-05-29 NSZ87C ARN → BUD May 29, 05:25 UTCMay 29, 07:10 UTC1h 45m
2026-05-28 NSZ278Y LIS → ARN May 28, 18:40 UTCMay 28, 22:30 UTC3h 50m
2026-05-28 NSZ2WK ARN → LIS May 28, 13:25 UTCMay 28, 17:20 UTC3h 55m
2026-05-28 NSZ4546 OTP → ARN May 28, 09:40 UTCMay 28, 12:20 UTC2h 40m
2026-05-28 NSZ4545 ARN → OTP May 28, 06:10 UTCMay 28, 08:25 UTC2h 15m
2026-05-27 NSZ4608 AYT → ARN May 27, 18:25 UTCMay 27, 22:20 UTC3h 55m
2026-05-27 NSZ4607 ARN → AYT May 27, 13:45 UTCMay 27, 17:20 UTC3h 35m
2026-05-27 NSZ2ES LGW → ARN May 27, 10:25 UTCMay 27, 12:25 UTC2h 0m
2026-05-27 NSZ51M ARN → LGW May 27, 06:49 UTCMay 27, 09:05 UTC2h 16m
2026-05-26 NSZ4114 OSL → ARN May 26, 18:10 UTCMay 26, 18:50 UTC40m
2026-05-26 NSZ4113 ARN → OSL May 26, 16:50 UTCMay 26, 17:35 UTC45m
2026-05-26 NSZ4110 OSL → ARN May 26, 14:35 UTCMay 26, 15:20 UTC45m
2026-05-26 NSZ4109 ARN → OSL May 26, 13:04 UTCMay 26, 13:54 UTC50m
2026-05-26 NSZ56J FCO → ARN May 26, 09:15 UTCMay 26, 12:00 UTC2h 45m
2026-05-26 NSZ5NE ARN → FCO May 26, 05:00 UTCMay 26, 07:34 UTC2h 35m
2026-05-25 NSZ4354 AMS → ARN May 25, 20:04 UTCMay 25, 21:35 UTC1h 30m
2026-05-25 NSZ4353 ARN → AMS May 25, 16:55 UTCMay 25, 18:45 UTC1h 50m
2026-05-25 NSZ6LA LGW → ARN May 25, 13:10 UTCMay 25, 15:05 UTC1h 55m
2026-05-25 NSZ5WU ARN → LGW May 25, 09:40 UTCMay 25, 12:00 UTC2h 20m
2026-05-24 NOZ826 OSL → ARN May 24, 18:15 UTCMay 24, 19:00 UTC45m
2026-05-24 NOZ3HC ARN → OSL May 24, 16:45 UTCMay 24, 17:30 UTC45m
2026-05-23 NSZ4328 BIA → ARN May 23, 19:40 UTCMay 23, 22:30 UTC2h 50m
2026-05-23 NSZ4327 ARN → BIA May 23, 16:30 UTCMay 23, 19:00 UTC2h 31m
2026-05-23 NSZ6LA LGW → ARN May 23, 13:45 UTCMay 23, 15:40 UTC1h 55m
2026-05-23 NSZ5WU ARN → LGW May 23, 09:55 UTCMay 23, 12:15 UTC2h 20m
2026-05-23 NSZ8GH UME → ARN May 23, 08:15 UTCMay 23, 08:50 UTC35m
2026-05-22 NSZ1KM ARN → UME May 22, 20:15 UTCMay 22, 20:50 UTC35m
2026-05-22 NSZ16Z UME → ARN May 22, 18:50 UTCMay 22, 19:25 UTC35m
2026-05-22 NSZ13R ARN → UME May 22, 16:55 UTCMay 22, 17:40 UTC45m
2026-05-22 NSZ12U UME → ARN May 22, 15:05 UTCMay 22, 15:50 UTC45m
2026-05-22 NSZ11N ARN → UME May 22, 12:55 UTCMay 22, 13:35 UTC40m
2026-05-22 NSZ2621 PRG → ARN May 22, 10:10 UTCMay 22, 11:50 UTC1h 40m
2026-05-22 NSZ2620 ARN → PRG May 22, 07:20 UTCMay 22, 09:00 UTC1h 40m
2026-05-22 NSZ6RD HEL → ARN May 22, 05:30 UTCMay 22, 06:15 UTC45m
2026-05-21 NSZ2887 AGP → HEL May 21, 18:35 UTCMay 21, 22:50 UTC4h 15m
2026-05-21 NSZ6HT HEL → AGP May 21, 13:05 UTCMay 21, 17:30 UTC4h 25m
2026-05-21 NSZ2767 LGW → HEL May 21, 09:15 UTCMay 21, 11:40 UTC2h 25m
2026-05-21 NSZ2766 HEL → LGW May 21, 05:10 UTCMay 21, 08:10 UTC3h 0m
2026-05-20 NSZ2913 ALC → HEL May 20, 18:25 UTCMay 20, 22:35 UTC4h 10m
2026-05-20 NSZ9WP HEL → ALC May 20, 13:05 UTCMay 20, 17:05 UTC4h 0m
2026-05-20 NSZ2845 SPU → HEL May 20, 09:40 UTCMay 20, 12:00 UTC2h 20m
2026-05-20 NSZ2844 HEL → SPU May 20, 05:35 UTCMay 20, 08:00 UTC2h 25m
2026-05-19 NSZ2889 AGP → HEL May 19, 19:40 UTCMay 20, 00:10 UTC4h 30m
2026-05-19 NSZ6HT HEL → AGP May 19, 14:05 UTCMay 19, 18:35 UTC4h 30m
2026-05-19 NSZ83AH AGP → HEL May 19, 08:45 UTCMay 19, 12:55 UTC4h 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-RTA page for operator, model, and routing details .

Mode-S 4ACA81 frequently asked

What is Mode-S code 4ACA81?
4ACA81 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RTA.
Where is Mode-S 4ACA81 registered?
Mode-S code 4ACA81 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4ACA81 broadcasting right now?
No active broadcast right now. Last signal was 8h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4ACA81, octal 22545201, decimal 4,901,505.
What flights does 4ACA81 operate?
Mode-S 4ACA81 has broadcast 20 distinct callsigns, including NSZ2616, NSZ8YC, NSZ6RD, NSZ2TH, NSZ2913.