sensors Mode-S transponder

4AC9D4

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-RNT · BOMBARDIER BD-100 Challenger 350

Hex
4AC9D4
Octal
22544724
Decimal
4,901,332
Country
SE
Tail
SE-RNT
Type
CL35
No current signal · last broadcast 1d ago
Flights observed
5
Distinct callsigns
2
Country
SE
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 4AC9D4.

Country allocation

The ICAO 24-bit address 4AC9D4 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 2 distinct

Callsign Airline Flights Last seen
EUW2317 - 4 2026-04-16
EUW2323 - 1 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-16 EUW2317 - Apr 16, 20:25 UTCApr 16, 20:40 UTC15m
2026-04-15 EUW2317 - Apr 15, 21:05 UTCApr 15, 22:00 UTC55m
2026-04-15 EUW2317 - Apr 15, 20:40 UTCApr 15, 21:00 UTC20m
2026-04-15 EUW2317 - Apr 15, 08:15 UTCApr 15, 08:55 UTC40m
2026-04-13 EUW2323 - Apr 13, 19:50 UTCApr 13, 20:25 UTC35m

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

Mode-S 4AC9D4 frequently asked

What is Mode-S code 4AC9D4?
4AC9D4 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-RNT.
Where is Mode-S 4AC9D4 registered?
Mode-S code 4AC9D4 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4AC9D4 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4AC9D4, octal 22544724, decimal 4,901,332.
What flights does 4AC9D4 operate?
Mode-S 4AC9D4 has broadcast 2 distinct callsigns, including EUW2317, EUW2323.