sensors Mode-S transponder

4ACA50

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RRP · BOEING 737-800

Hex
4ACA50
Octal
22545120
Decimal
4,901,456
Country
SE
Tail
SE-RRP
Type
B738
Photo of SE-RRP
Broadcasting now · callsign NSZ41G · 12,250 ft
Flights observed
14
Distinct callsigns
12
Country
SE
Last broadcast
20h ago

Current position

4ACA50 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4ACA50 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 12 distinct

Callsign Airline Flights Last seen
NSZ56J Norwegian Air Sweden AOC 2 2026-04-13
NSZ13R - 2 2026-04-13
NSZ8KY - 1 2026-04-12
NSZ8GH Norwegian Air Sweden AOC 1 2026-04-14
NSZ5NE - 1 2026-04-13
NSZ5B Norwegian Air Sweden AOC 1 2026-04-14
NSZ3YT Norwegian Air Sweden AOC 1 2026-04-14
NSZ2EF Norwegian Air Sweden AOC 1 2026-04-14
NSZ1KM - 1 2026-04-13
NSZ16Z - 1 2026-04-13
NSZ12U - 1 2026-04-13
NSZ11N - 1 2026-04-13

Recent flights last 14

DateFlightRouteTakeoffLandingDuration
2026-04-14 NSZ3YT ARN → NCE Apr 14, 09:40 UTCApr 14, 11:05 UTC1h 25m
2026-04-14 NSZ8GH UME → ARN Apr 14, 08:05 UTCApr 14, 08:40 UTC35m
2026-04-14 NSZ5B ARN → UME Apr 14, 06:30 UTCApr 14, 07:05 UTC35m
2026-04-14 NSZ2EF UME → ARN Apr 14, 05:15 UTCApr 14, 05:35 UTC20m
2026-04-13 NSZ1KM - Apr 13, 18:45 UTCApr 13, 19:15 UTC30m
2026-04-13 NSZ16Z - Apr 13, 17:15 UTCApr 13, 18:00 UTC45m
2026-04-13 NSZ13R - Apr 13, 16:15 UTCApr 13, 16:25 UTC10m
2026-04-13 NSZ13R - Apr 13, 15:50 UTCApr 13, 16:15 UTC25m
2026-04-13 NSZ12U - Apr 13, 14:30 UTCApr 13, 15:15 UTC45m
2026-04-13 NSZ11N - Apr 13, 12:55 UTCApr 13, 13:25 UTC30m
2026-04-13 NSZ56J FCO → ARN Apr 13, 11:55 UTCApr 13, 12:15 UTC20m
2026-04-13 NSZ56J FCO → ARN Apr 13, 09:35 UTCApr 13, 12:15 UTC2h 40m
2026-04-13 NSZ5NE - Apr 13, 05:05 UTCApr 13, 07:55 UTC2h 50m
2026-04-12 NSZ8KY - Apr 12, 18:45 UTCApr 12, 20:15 UTC1h 30m

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

Mode-S 4ACA50 frequently asked

What is Mode-S code 4ACA50?
4ACA50 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RRP.
Where is Mode-S 4ACA50 registered?
Mode-S code 4ACA50 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4ACA50 broadcasting right now?
Yes. Mode-S 4ACA50 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4ACA50, octal 22545120, decimal 4,901,456.
What flights does 4ACA50 operate?
Mode-S 4ACA50 has broadcast 12 distinct callsigns, including NSZ56J, NSZ13R, NSZ8KY, NSZ8GH, NSZ5NE.