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
Broadcasting now · callsign NSZ5PK · 37,000 ft
Flights observed
452
Distinct callsigns
20
Country
SE
Last broadcast
55m ago

Current position

4ACA81 is currently broadcasting. Map zoomed to live position.

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
NSZ6LA - 5 2026-07-09
NSZ5WU - 5 2026-07-09
NSZ5NE - 5 2026-07-08
NSZ56J Norwegian Air Sweden AOC 5 2026-07-08
NSZ4508 - 5 2026-07-10
NSZ4507 - 5 2026-07-10
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
NSZ87C - 4 2026-07-10
NSZ6HT Norwegian Air Sweden AOC 4 2026-05-21
NSZ60X - 4 2026-07-12
NSZ59T - 4 2026-07-12
NSZ51M - 4 2026-06-16

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 NSZ5PK - Jul 14, 05:50 UTCJul 14, 06:15 UTC25m
2026-07-13 NSZ4122 OSL → ARN Jul 13, 19:30 UTCJul 13, 20:20 UTC50m
2026-07-13 NSZ4121 ARN → OSL Jul 13, 18:00 UTCJul 13, 18:40 UTC40m
2026-07-13 NSZ4PU - Jul 13, 14:45 UTCJul 13, 17:00 UTC2h 15m
2026-07-13 NSZ4329 - Jul 13, 11:15 UTCJul 13, 13:40 UTC2h 25m
2026-07-13 NSZ4340 - Jul 13, 07:50 UTCJul 13, 10:00 UTC2h 10m
2026-07-13 NSZ39TP - Jul 13, 04:45 UTCJul 13, 06:55 UTC2h 10m
2026-07-12 NSZ60X LGW → ARN Jul 12, 19:35 UTCJul 12, 21:50 UTC2h 15m
2026-07-12 NSZ59T ARN → LGW Jul 12, 16:15 UTCJul 12, 18:50 UTC2h 35m
2026-07-12 NSZ4506 BER → ARN Jul 12, 14:05 UTCJul 12, 15:15 UTC1h 10m
2026-07-12 NSZ4505 ARN → BER Jul 12, 11:25 UTCJul 12, 12:45 UTC1h 20m
2026-07-12 NSZ4546 - Jul 12, 07:55 UTCJul 12, 10:25 UTC2h 30m
2026-07-12 NSZ4545 ARN → OTP Jul 12, 04:25 UTCJul 12, 06:45 UTC2h 20m
2026-07-11 NSZ4382 RHO → ARN Jul 11, 22:15 UTCJul 12, 01:45 UTC3h 30m
2026-07-11 NSZ4381 ARN → RHO Jul 11, 17:15 UTCJul 11, 20:45 UTC3h 30m
2026-07-11 NSZ4156 CPH → ARN Jul 11, 15:25 UTCJul 11, 16:15 UTC50m
2026-07-11 NSZ4155 ARN → CPH Jul 11, 13:30 UTCJul 11, 14:20 UTC50m
2026-07-11 NSZ5YD - Jul 11, 09:05 UTCJul 11, 12:05 UTC3h 0m
2026-07-11 NSZ4257 - Jul 11, 04:35 UTCJul 11, 07:25 UTC2h 50m
2026-07-10 NSZ4508 - Jul 10, 19:55 UTCJul 10, 21:15 UTC1h 20m
2026-07-10 NSZ4507 ARN → BER Jul 10, 17:45 UTCJul 10, 19:00 UTC1h 15m
2026-07-10 NSZ48U BUD → ARN Jul 10, 14:45 UTCJul 10, 16:45 UTC2h 0m
2026-07-10 NSZ87C ARN → BUD Jul 10, 12:15 UTCJul 10, 14:00 UTC1h 45m
2026-07-10 NSZ4PU - Jul 10, 08:55 UTCJul 10, 11:20 UTC2h 25m
2026-07-10 NSZ4329 - Jul 10, 05:00 UTCJul 10, 07:20 UTC2h 20m
2026-07-09 NSZ60X - Jul 9, 19:20 UTCJul 9, 21:15 UTC1h 55m
2026-07-09 NSZ59T ARN → LGW Jul 9, 15:50 UTCJul 9, 18:00 UTC2h 10m
2026-07-09 NSZ6LA - Jul 9, 12:35 UTCJul 9, 14:35 UTC2h 0m
2026-07-09 NSZ5WU ARN → LGW Jul 9, 09:10 UTCJul 9, 11:20 UTC2h 10m
2026-07-09 NSZ4004 - Jul 9, 07:00 UTCJul 9, 07:45 UTC45m
2026-07-09 NSZ9UA ARN → UME Jul 9, 05:25 UTCJul 9, 06:00 UTC35m
2026-07-08 NSZ4608 - Jul 8, 18:25 UTCJul 8, 22:15 UTC3h 50m
2026-07-08 NSZ4607 - Jul 8, 13:50 UTCJul 8, 17:15 UTC3h 25m
2026-07-08 NSZ56J FCO → ARN Jul 8, 09:20 UTCJul 8, 12:05 UTC2h 45m
2026-07-08 NSZ5NE - Jul 8, 05:10 UTCJul 8, 07:35 UTC2h 25m
2026-07-07 NSZ4527 ARN → ARN Jul 7, 10:15 UTCJul 7, 20:50 UTC10h 35m
2026-07-07 NSZ38K - Jul 7, 07:25 UTCJul 7, 08:30 UTC1h 5m
2026-07-07 NSZ35A - Jul 7, 05:35 UTCJul 7, 06:35 UTC1h 0m
2026-07-06 NSZ60X LGW → ARN Jul 6, 19:20 UTCJul 6, 21:15 UTC1h 55m
2026-07-06 NSZ59T ARN → LGW Jul 6, 15:45 UTCJul 6, 18:10 UTC2h 25m
2026-07-06 NSZ6LA LGW → ARN Jul 6, 12:50 UTCJul 6, 14:50 UTC2h 0m
2026-07-06 NSZ5WU ARN → LGW Jul 6, 09:10 UTCJul 6, 11:40 UTC2h 30m
2026-07-06 NSZ4004 - Jul 6, 07:00 UTCJul 6, 07:45 UTC45m
2026-07-06 NSZ9UA ARN → UME Jul 6, 05:25 UTCJul 6, 06:00 UTC35m
2026-07-05 NSZ4354 - Jul 5, 19:55 UTCJul 5, 21:30 UTC1h 35m
2026-07-05 NSZ4353 - Jul 5, 17:00 UTCJul 5, 18:45 UTC1h 45m
2026-07-05 NSZ4556 VNO → ARN Jul 5, 15:10 UTCJul 5, 16:15 UTC1h 5m
2026-07-05 NSZ4555 ARN → VNO Jul 5, 13:20 UTCJul 5, 14:25 UTC1h 5m
2026-07-05 NSZ56J FCO → ARN Jul 5, 09:05 UTCJul 5, 11:55 UTC2h 50m
2026-07-05 NSZ5NE - Jul 5, 05:05 UTCJul 5, 07:40 UTC2h 35m

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?
Yes. Mode-S 4ACA81 is currently airborne.
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, NSZ6LA, NSZ5WU.