sensors Mode-S transponder

4A9973

ICAO 24-bit transponder address · allocated to Sweden

Currently assigned to SE-FKS · CESSNA 182 Skylane

Hex
4A9973
Octal
22514563
Decimal
4,888,947
Country
SE
Tail
SE-FKS
Type
C182
No current signal · last broadcast 6h ago
Flights observed
29
Distinct callsigns
1
Country
SE
Last broadcast
6h ago

Last known position

Most recent position reported by Mode-S 4A9973.

Country allocation

The ICAO 24-bit address 4A9973 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 1 distinct

Callsign Airline Flights Last seen
SEFKS - 29 2026-07-13

Recent flights last 29

DateFlightRouteTakeoffLandingDuration
2026-07-13 SEFKS - Jul 13, 16:30 UTCJul 13, 17:05 UTC35m
2026-07-13 SEFKS - Jul 13, 14:40 UTCJul 13, 15:05 UTC25m
2026-07-13 SEFKS - Jul 13, 12:05 UTCJul 13, 13:30 UTC1h 25m
2026-07-12 SEFKS - Jul 12, 12:05 UTCJul 12, 12:55 UTC50m
2026-07-10 SEFKS - Jul 10, 10:00 UTCJul 10, 10:50 UTC50m
2026-07-09 SEFKS - Jul 9, 17:35 UTCJul 9, 18:20 UTC45m
2026-07-09 SEFKS - Jul 9, 14:10 UTCJul 9, 14:45 UTC35m
2026-07-09 SEFKS - Jul 9, 12:15 UTCJul 9, 12:55 UTC40m
2026-07-07 SEFKS - Jul 7, 17:10 UTCJul 7, 17:55 UTC45m
2026-07-07 SEFKS - Jul 7, 15:25 UTCJul 7, 15:40 UTC15m
2026-07-04 SEFKS - Jul 4, 11:55 UTCJul 4, 12:30 UTC35m
2026-06-29 SEFKS - Jun 29, 19:35 UTCJun 29, 20:40 UTC1h 5m
2026-06-27 SEFKS - Jun 27, 10:29 UTCJun 27, 11:39 UTC1h 10m
2026-06-27 SEFKS - Jun 27, 08:39 UTCJun 27, 09:09 UTC30m
2026-06-25 SEFKS - Jun 25, 12:25 UTCJun 25, 13:00 UTC35m
2026-06-24 SEFKS - Jun 24, 15:59 UTCJun 24, 16:24 UTC25m
2026-06-23 SEFKS - Jun 23, 09:54 UTCJun 23, 10:19 UTC25m
2026-06-21 SEFKS - Jun 21, 11:24 UTCJun 21, 12:35 UTC1h 10m
2026-06-18 SEFKS - Jun 18, 19:35 UTCJun 18, 20:10 UTC35m
2026-06-18 SEFKS - Jun 18, 18:25 UTCJun 18, 18:50 UTC25m
2026-06-17 SEFKS - Jun 17, 20:00 UTCJun 17, 20:35 UTC35m
2026-06-17 SEFKS - Jun 17, 16:05 UTCJun 17, 17:30 UTC1h 25m
2026-06-17 SEFKS - Jun 17, 14:05 UTCJun 17, 14:50 UTC45m
2026-06-16 SEFKS - Jun 16, 16:05 UTCJun 16, 16:50 UTC45m
2026-06-13 SEFKS - Jun 13, 10:05 UTCJun 13, 10:40 UTC35m
2026-06-09 SEFKS - Jun 9, 17:20 UTCJun 9, 18:45 UTC1h 25m
2026-05-30 SEFKS - May 30, 11:00 UTCMay 30, 12:20 UTC1h 20m
2026-05-29 SEFKS - May 29, 12:20 UTCMay 29, 12:50 UTC30m
2026-05-25 SEFKS - May 25, 21:24 UTCMay 25, 22:49 UTC1h 25m

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

Mode-S 4A9973 frequently asked

What is Mode-S code 4A9973?
4A9973 is an ICAO 24-bit transponder address. Allocated to Sweden. Assigned to SE-FKS.
Where is Mode-S 4A9973 registered?
Mode-S code 4A9973 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4A9973 broadcasting right now?
No active broadcast right now. Last signal was 6h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4A9973, octal 22514563, decimal 4,888,947.
What flights does 4A9973 operate?
Mode-S 4A9973 has broadcast 1 distinct callsign, including SEFKS.