sensors Mode-S transponder

4A91B2

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-DMR · AIRBUS A-321neo

Hex
4A91B2
Octal
22510662
Decimal
4,886,962
Country
SE
Tail
SE-DMR
Type
A21N
Photo of SE-DMR
Broadcasting now · callsign SAS924 · 32,975 ft
Flights observed
6
Distinct callsigns
3
Country
SE
Last broadcast
23h ago

Current position

4A91B2 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4A91B2 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 3 distinct

Callsign Airline Flights Last seen
SAS923 - 4 2026-04-13
SAS924 Scandinavian Airlines System 1 2026-04-13
SAS908 Scandinavian Airlines System 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 SAS924 CPH → IAD Apr 13, 21:50 UTCApr 13, 23:25 UTC1h 35m
2026-04-13 SAS923 - Apr 13, 17:25 UTCApr 13, 19:25 UTC2h 0m
2026-04-13 SAS923 - Apr 13, 13:25 UTCApr 13, 14:00 UTC35m
2026-04-13 SAS923 - Apr 13, 11:55 UTCApr 13, 14:00 UTC2h 5m
2026-04-13 SAS923 - Apr 13, 11:30 UTCApr 13, 12:10 UTC40m
2026-04-13 SAS908 EWR → OSL Apr 13, 04:40 UTCApr 13, 05:20 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-DMR page for operator, model, and routing details .

Mode-S 4A91B2 frequently asked

What is Mode-S code 4A91B2?
4A91B2 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-DMR.
Where is Mode-S 4A91B2 registered?
Mode-S code 4A91B2 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4A91B2 broadcasting right now?
Yes. Mode-S 4A91B2 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4A91B2, octal 22510662, decimal 4,886,962.
What flights does 4A91B2 operate?
Mode-S 4A91B2 has broadcast 3 distinct callsigns, including SAS923, SAS924, SAS908.