sensors Mode-S transponder

4AC985

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RLE · BOEING 757-200

Hex
4AC985
Octal
22544605
Decimal
4,901,253
Country
SE
Tail
SE-RLE
Type
B752
No current signal · last broadcast 20h ago
Flights observed
6
Distinct callsigns
4
Country
SE
Last broadcast
20h ago

Last known position

Most recent position reported by Mode-S 4AC985.

Country allocation

The ICAO 24-bit address 4AC985 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 4 distinct

Callsign Airline Flights Last seen
SWN365 - 2 2026-04-13
SWN364 - 2 2026-04-13
SWN383 - 1 2026-04-14
SWN382 - 1 2026-04-14

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 SWN383 - Apr 14, 10:30 UTCApr 14, 11:05 UTC35m
2026-04-14 SWN382 - Apr 14, 07:40 UTCApr 14, 09:05 UTC1h 25m
2026-04-13 SWN365 - Apr 13, 19:50 UTCApr 13, 20:05 UTC15m
2026-04-13 SWN365 - Apr 13, 18:50 UTCApr 13, 20:05 UTC1h 15m
2026-04-13 SWN364 - Apr 13, 16:15 UTCApr 13, 17:35 UTC1h 20m
2026-04-13 SWN364 - Apr 13, 16:05 UTCApr 13, 16:15 UTC10m

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

Mode-S 4AC985 frequently asked

What is Mode-S code 4AC985?
4AC985 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RLE.
Where is Mode-S 4AC985 registered?
Mode-S code 4AC985 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4AC985 broadcasting right now?
No active broadcast right now. Last signal was 20h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4AC985, octal 22544605, decimal 4,901,253.
What flights does 4AC985 operate?
Mode-S 4AC985 has broadcast 4 distinct callsigns, including SWN365, SWN364, SWN383, SWN382.