sensors Mode-S transponder

4ACA8C

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RTL · BOEING 737 MAX 8

Hex
4ACA8C
Octal
22545214
Decimal
4,901,516
Country
SE
Tail
SE-RTL
Type
B38M
No current signal · last broadcast 12h ago
Flights observed
10
Distinct callsigns
6
Country
SE
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S 4ACA8C.

Country allocation

The ICAO 24-bit address 4ACA8C 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 6 distinct

Callsign Airline Flights Last seen
NSZ4623 - 3 2026-04-13
NSZ5NE Norwegian Air Sweden AOC 2 2026-04-14
NSZ4624 - 2 2026-04-13
NSZ56J Norwegian Air Sweden AOC 1 2026-04-14
NSZ2FU - 1 2026-04-12
NSZ2617 - 1 2026-04-12

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-14 NSZ56J FCO → ARN Apr 14, 09:20 UTCApr 14, 11:05 UTC1h 45m
2026-04-14 NSZ5NE ARN → FCO Apr 14, 07:10 UTCApr 14, 08:05 UTC55m
2026-04-14 NSZ5NE ARN → FCO Apr 14, 05:15 UTCApr 14, 07:10 UTC1h 55m
2026-04-13 NSZ4624 - Apr 13, 19:50 UTCApr 13, 21:45 UTC1h 55m
2026-04-13 NSZ4624 - Apr 13, 16:35 UTCApr 13, 20:10 UTC3h 35m
2026-04-13 NSZ4623 - Apr 13, 12:20 UTCApr 13, 14:25 UTC2h 5m
2026-04-13 NSZ4623 - Apr 13, 11:55 UTCApr 13, 14:25 UTC2h 30m
2026-04-13 NSZ4623 - Apr 13, 09:55 UTCApr 13, 12:15 UTC2h 20m
2026-04-12 NSZ2FU - Apr 12, 18:50 UTCApr 12, 19:30 UTC40m
2026-04-12 NSZ2617 ARN → HEL Apr 12, 17:30 UTCApr 12, 18:10 UTC40m

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

Mode-S 4ACA8C frequently asked

What is Mode-S code 4ACA8C?
4ACA8C is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RTL.
Where is Mode-S 4ACA8C registered?
Mode-S code 4ACA8C is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4ACA8C broadcasting right now?
No active broadcast right now. Last signal was 12h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4ACA8C, octal 22545214, decimal 4,901,516.
What flights does 4ACA8C operate?
Mode-S 4ACA8C has broadcast 6 distinct callsigns, including NSZ4623, NSZ5NE, NSZ4624, NSZ56J, NSZ2FU.