sensors Mode-S transponder

44CD73

ICAO 24-bit transponder address · allocated to Belgium

Currently assigned to OO-SKS · CESSNA 560XL Citation XLS

Hex
44CD73
Octal
21146563
Decimal
4,509,043
Country
BE
Tail
OO-SKS
Type
C56X
No current signal · last broadcast 18h ago
Flights observed
11
Distinct callsigns
1
Country
BE
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S 44CD73.

Country allocation

The ICAO 24-bit address 44CD73 falls within the block assigned to Belgium (BE) by ICAO Annex 10, Volume III. Every aircraft registered in Belgium 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
OOSKS - 11 2026-04-14

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-04-14 OOSKS - Apr 14, 09:25 UTCApr 14, 11:05 UTC1h 40m
2026-04-14 OOSKS - Apr 14, 07:00 UTCApr 14, 07:10 UTC10m
2026-04-13 OOSKS - Apr 13, 16:15 UTCApr 13, 17:20 UTC1h 5m
2026-04-13 OOSKS ANR → ANR Apr 13, 16:10 UTCApr 13, 17:20 UTC1h 10m
2026-04-13 OOSKS ANR → ANR Apr 13, 14:25 UTCApr 13, 15:35 UTC1h 10m
2026-04-13 OOSKS - Apr 13, 12:20 UTCApr 13, 13:05 UTC45m
2026-04-13 OOSKS - Apr 13, 12:05 UTCApr 13, 12:15 UTC10m
2026-04-13 OOSKS - Apr 13, 10:25 UTCApr 13, 10:55 UTC30m
2026-04-13 OOSKS - Apr 13, 08:20 UTCApr 13, 08:40 UTC20m
2026-04-13 OOSKS ANR → ANR Apr 13, 07:55 UTCApr 13, 08:40 UTC45m
2026-04-13 OOSKS - Apr 13, 07:40 UTCApr 13, 08:15 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 OO-SKS page for operator, model, and routing details .

Mode-S 44CD73 frequently asked

What is Mode-S code 44CD73?
44CD73 is an ICAO 24-bit transponder address. Allocated to Belgium. Assigned to OO-SKS.
Where is Mode-S 44CD73 registered?
Mode-S code 44CD73 is allocated to Belgium (BE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 44CD73 broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 44CD73, octal 21146563, decimal 4,509,043.
What flights does 44CD73 operate?
Mode-S 44CD73 has broadcast 1 distinct callsign, including OOSKS.