sensors Mode-S transponder

4AC839

ICAO 24-bit transponder address · allocated to Sweden

Hex
4AC839
Octal
22544071
Decimal
4,900,921
Country
SE
No current signal · last broadcast 7d ago
Flights observed
26
Distinct callsigns
1
Country
SE
Last broadcast
7d ago

Last known position

Most recent position reported by Mode-S 4AC839.

Country allocation

The ICAO 24-bit address 4AC839 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
JET1 - 26 2026-07-20

Recent flights last 26

DateFlightRouteTakeoffLandingDuration
2026-07-20 JET1 JMK → KVA Jul 20, 14:15 UTCJul 20, 15:00 UTC45m
2026-07-20 JET1 - Jul 20, 10:25 UTCJul 20, 13:05 UTC2h 40m
2026-07-20 JET1 - Jul 20, 07:45 UTCJul 20, 08:35 UTC50m
2026-07-17 JET1 - Jul 17, 12:00 UTCJul 17, 12:45 UTC45m
2026-07-17 JET1 BER → MMX Jul 17, 10:30 UTCJul 17, 11:10 UTC40m
2026-07-01 JET1 LIN → BER Jul 1, 17:50 UTCJul 1, 19:00 UTC1h 10m
2026-06-25 JET1 PMI → LIN Jun 25, 12:50 UTCJun 25, 14:04 UTC1h 15m
2026-06-24 JET1 - Jun 24, 15:24 UTCJun 24, 16:29 UTC1h 5m
2026-06-24 JET1 - Jun 24, 11:05 UTCJun 24, 13:14 UTC2h 10m
2026-06-17 JET1 - Jun 17, 13:55 UTCJun 17, 15:20 UTC1h 25m
2026-06-16 JET1 - Jun 16, 18:15 UTCJun 16, 21:35 UTC3h 21m
2026-06-16 JET1 - Jun 16, 13:44 UTCJun 16, 17:19 UTC3h 35m
2026-06-14 JET1 - Jun 14, 16:55 UTCJun 14, 17:30 UTC35m
2026-06-14 JET1 PRG → GOT Jun 14, 14:00 UTCJun 14, 15:15 UTC1h 15m
2026-06-10 JET1 CGN → PRG Jun 10, 14:10 UTCJun 10, 14:55 UTC45m
2026-06-10 JET1 BMA → CGN Jun 10, 09:05 UTCJun 10, 10:40 UTC1h 35m
2026-06-08 JET1 NCE → BMA Jun 8, 14:40 UTCJun 8, 17:00 UTC2h 20m
2026-06-08 JET1 - Jun 8, 01:55 UTCJun 8, 02:20 UTC25m
2026-06-04 JET1 - Jun 4, 16:05 UTCJun 4, 16:30 UTC25m
2026-06-04 JET1 BMA → NCE Jun 4, 12:10 UTCJun 4, 14:50 UTC2h 40m
2026-06-03 JET1 - Jun 3, 16:25 UTCJun 3, 17:35 UTC1h 10m
2026-05-26 JET1 - May 26, 06:25 UTCMay 26, 07:40 UTC1h 15m
2026-05-17 JET1 - May 17, 15:10 UTCMay 17, 18:45 UTC3h 35m
2026-05-12 JET1 - May 12, 10:05 UTCMay 12, 14:00 UTC3h 55m
2026-04-28 JET1 - Apr 28, 16:05 UTCApr 28, 18:20 UTC2h 15m
2026-04-28 JET1 BMA → GVA Apr 28, 06:55 UTCApr 28, 09:00 UTC2h 5m

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.

Mode-S 4AC839 frequently asked

What is Mode-S code 4AC839?
4AC839 is an ICAO 24-bit transponder address. Allocated to Sweden.
Where is Mode-S 4AC839 registered?
Mode-S code 4AC839 is allocated to Sweden (SE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4AC839 broadcasting right now?
No active broadcast right now. Last signal was 7d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4AC839, octal 22544071, decimal 4,900,921.
What flights does 4AC839 operate?
Mode-S 4AC839 has broadcast 1 distinct callsign, including JET1.