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sensors Mode-S transponder

4C066D

ICAO 24-bit transponder address · allocated to Serbia

Currently assigned to YU-BTN · CESSNA 525B Citation CJ3

Hex
4C066D
Octal
23003155
Decimal
4,982,381
Country
RS
Tail
YU-BTN
Type
C25B
No current signal · last broadcast 1h ago
Flights observed
129
Distinct callsigns
2
Country
RS
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 4C066D.

Country allocation

The ICAO 24-bit address 4C066D falls within the block assigned to Serbia (RS) by ICAO Annex 10, Volume III. Every aircraft registered in Serbia 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 2 distinct

Callsign Airline Flights Last seen
FUU543N - 128 2026-07-14
FUU231A - 1 2026-05-31

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 FUU543N - Jul 14, 10:55 UTCJul 14, 11:40 UTC45m
2026-07-13 FUU543N - Jul 13, 10:35 UTCJul 13, 12:45 UTC2h 10m
2026-07-13 FUU543N - Jul 13, 08:10 UTCJul 13, 09:00 UTC50m
2026-07-12 FUU543N RTM → MAD Jul 12, 00:25 UTCJul 12, 02:40 UTC2h 15m
2026-07-11 FUU543N - Jul 11, 11:05 UTCJul 11, 12:15 UTC1h 10m
2026-07-11 FUU543N - Jul 11, 07:00 UTCJul 11, 09:40 UTC2h 40m
2026-07-11 FUU543N DBV → JMK Jul 11, 04:55 UTCJul 11, 06:15 UTC1h 20m
2026-07-10 FUU543N BRN → DBV Jul 10, 13:25 UTCJul 10, 14:55 UTC1h 30m
2026-07-10 FUU543N - Jul 10, 10:05 UTCJul 10, 11:15 UTC1h 10m
2026-07-10 FUU543N - Jul 10, 08:05 UTCJul 10, 09:00 UTC55m
2026-07-10 FUU543N - Jul 10, 04:50 UTCJul 10, 06:10 UTC1h 20m
2026-07-08 FUU543N - Jul 8, 13:15 UTCJul 8, 14:40 UTC1h 25m
2026-07-08 FUU543N - Jul 8, 06:10 UTCJul 8, 07:15 UTC1h 5m
2026-07-07 FUU543N BUD → BTS Jul 7, 16:00 UTCJul 7, 16:25 UTC25m
2026-07-07 FUU543N - Jul 7, 12:10 UTCJul 7, 13:15 UTC1h 5m
2026-07-06 FUU543N - Jul 6, 13:00 UTCJul 6, 17:45 UTC4h 45m
2026-07-05 FUU543N - Jul 5, 15:25 UTCJul 5, 15:55 UTC30m
2026-07-05 FUU543N - Jul 5, 12:25 UTCJul 5, 13:45 UTC1h 20m
2026-07-04 FUU543N - Jul 4, 18:40 UTCJul 4, 20:05 UTC1h 25m
2026-07-04 FUU543N - Jul 4, 16:15 UTCJul 4, 17:15 UTC1h 0m
2026-07-04 FUU543N - Jul 4, 13:25 UTCJul 4, 15:25 UTC2h 0m
2026-07-03 FUU543N - Jul 3, 10:30 UTCJul 3, 11:30 UTC1h 0m
2026-07-02 FUU543N - Jul 2, 23:00 UTCJul 3, 00:40 UTC1h 40m
2026-07-02 FUU543N - Jul 2, 12:40 UTCJul 2, 13:30 UTC50m
2026-07-02 FUU543N - Jul 2, 09:30 UTCJul 2, 11:25 UTC1h 55m
2026-07-01 FUU543N - Jul 1, 14:10 UTCJul 1, 14:30 UTC20m
2026-07-01 FUU543N - Jul 1, 09:35 UTCJul 1, 10:10 UTC35m
2026-07-01 FUU543N - Jul 1, 06:15 UTCJul 1, 08:15 UTC2h 0m
2026-06-30 FUU543N - Jun 30, 13:10 UTCJun 30, 15:10 UTC2h 0m
2026-06-30 FUU543N - Jun 30, 10:25 UTCJun 30, 11:55 UTC1h 30m
2026-06-29 FUU543N - Jun 29, 12:55 UTCJun 29, 13:44 UTC50m
2026-06-29 FUU543N - Jun 29, 10:20 UTCJun 29, 12:05 UTC1h 45m
2026-06-28 FUU543N - Jun 28, 08:29 UTCJun 28, 09:10 UTC40m
2026-06-28 FUU543N - Jun 28, 06:44 UTCJun 28, 07:25 UTC40m
2026-06-27 FUU543N - Jun 27, 11:39 UTCJun 27, 13:15 UTC1h 35m
2026-06-27 FUU543N BEG → JMK Jun 27, 09:24 UTCJun 27, 11:00 UTC1h 35m
2026-06-26 FUU543N DBV → BEG Jun 26, 18:04 UTCJun 26, 18:44 UTC40m
2026-06-26 FUU543N BUD → DBV Jun 26, 15:25 UTCJun 26, 16:24 UTC1h 0m
2026-06-23 FUU543N NCE → BUD Jun 23, 21:24 UTCJun 23, 23:05 UTC1h 40m
2026-06-23 FUU543N ZRH → NCE Jun 23, 18:25 UTCJun 23, 19:19 UTC55m
2026-06-21 FUU543N - Jun 21, 16:30 UTCJun 21, 17:54 UTC1h 25m
2026-06-21 FUU543N - Jun 21, 11:24 UTCJun 21, 12:10 UTC45m
2026-06-21 FUU543N - Jun 21, 08:20 UTCJun 21, 10:19 UTC2h 0m
2026-06-20 FUU543N - Jun 20, 08:59 UTCJun 20, 09:39 UTC40m
2026-06-20 FUU543N - Jun 20, 07:00 UTCJun 20, 07:39 UTC40m
2026-06-20 FUU543N - Jun 20, 05:19 UTCJun 20, 05:49 UTC30m
2026-06-19 FUU543N - Jun 19, 15:59 UTCJun 19, 16:59 UTC1h 0m
2026-06-18 FUU543N BEG → ATH Jun 18, 06:50 UTCJun 18, 08:10 UTC1h 20m
2026-06-15 FUU543N - Jun 15, 14:40 UTCJun 15, 15:04 UTC25m
2026-06-15 FUU543N - Jun 15, 12:30 UTCJun 15, 13:20 UTC50m

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 YU-BTN page for operator, model, and routing details .

Mode-S 4C066D frequently asked

What is Mode-S code 4C066D?
4C066D is an ICAO 24-bit transponder address. Allocated to Serbia. Assigned to YU-BTN.
Where is Mode-S 4C066D registered?
Mode-S code 4C066D is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C066D 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 4C066D, octal 23003155, decimal 4,982,381.
What flights does 4C066D operate?
Mode-S 4C066D has broadcast 2 distinct callsigns, including FUU543N, FUU231A.