sensors Mode-S transponder

4598D4

ICAO 24-bit transponder address · allocated to Denmark

Currently assigned to OY-FFT · TECNAM P-2006T

Hex
4598D4
Octal
21314324
Decimal
4,561,108
Country
DK
Tail
OY-FFT
Type
P06T
No current signal · last broadcast 1h ago
Flights observed
6
Distinct callsigns
1
Country
DK
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 4598D4.

Country allocation

The ICAO 24-bit address 4598D4 falls within the block assigned to Denmark (DK) by ICAO Annex 10, Volume III. Every aircraft registered in Denmark 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
EW596AL - 6 2026-05-21

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-05-21 EW596AL - May 21, 10:15 UTCMay 21, 10:45 UTC30m
2026-05-21 EW596AL - May 21, 06:30 UTCMay 21, 06:55 UTC25m
2026-05-21 EW596AL - May 21, 04:55 UTCMay 21, 05:05 UTC10m
2026-05-17 EW596AL - May 17, 15:45 UTCMay 17, 16:30 UTC45m
2026-05-16 EW596AL - May 16, 13:11 UTCMay 16, 13:35 UTC25m
2026-05-15 EW596AL - May 15, 14:30 UTCMay 15, 15:10 UTC39m

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 OY-FFT page for operator, model, and routing details .

Mode-S 4598D4 frequently asked

What is Mode-S code 4598D4?
4598D4 is an ICAO 24-bit transponder address. Allocated to Denmark. Assigned to OY-FFT.
Where is Mode-S 4598D4 registered?
Mode-S code 4598D4 is allocated to Denmark (DK). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4598D4 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4598D4, octal 21314324, decimal 4,561,108.
What flights does 4598D4 operate?
Mode-S 4598D4 has broadcast 1 distinct callsign, including EW596AL.