Apparatus

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sensors Mode-S transponder

4C01F3

ICAO 24-bit transponder address · allocated to Serbia

Currently assigned to YU-APT · AIRBUS A-320

Hex
4C01F3
Octal
23000763
Decimal
4,981,235
Country
RS
Tail
YU-APT
Type
A320
No current signal · last broadcast 2h ago
Flights observed
393
Distinct callsigns
20
Country
RS
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 4C01F3.

Country allocation

The ICAO 24-bit address 4C01F3 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 20 distinct

Callsign Airline Flights Last seen
ASL134 - 20 2026-07-09
ASL132 - 18 2026-06-17
ASL133 Spurling Aviation 15 2026-06-17
ASL135 - 11 2026-07-10
ASL63H - 9 2026-07-02
ASL51N - 9 2026-07-02
ASL130 - 9 2026-06-23
ASL73B Spurling Aviation 8 2026-07-02
ASL32A Spurling Aviation 8 2026-07-02
ASL87A - 6 2026-07-07
ASL86U - 6 2026-07-07
ASL73J - 6 2026-07-05
ASL11B - 6 2026-07-05
ASL9975 - 5 2026-07-17
ASL9974 - 5 2026-07-17
ASL71H Spurling Aviation 5 2026-06-15
ASL53X - 5 2026-07-14
ASL47E Spurling Aviation 5 2026-06-15
ASL45X Spurling Aviation 5 2026-06-26
ASL30L - 5 2026-07-12

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-17 ASL9975 - Jul 17, 22:35 UTCJul 18, 00:15 UTC1h 40m
2026-07-17 ASL9974 - Jul 17, 19:20 UTCJul 17, 20:55 UTC1h 35m
2026-07-17 ASL75J - Jul 17, 17:25 UTCJul 17, 17:55 UTC30m
2026-07-17 ASL64X - Jul 17, 15:40 UTCJul 17, 16:00 UTC20m
2026-07-17 ASL69A - Jul 17, 13:05 UTCJul 17, 14:20 UTC1h 15m
2026-07-17 ASL31D - Jul 17, 10:10 UTCJul 17, 11:35 UTC1h 25m
2026-07-17 ASL27J BEG → GOT Jul 17, 06:54 UTCJul 17, 08:49 UTC1h 55m
2026-07-17 ASL22A BEG → AYT Jul 17, 03:20 UTCJul 17, 04:59 UTC1h 40m
2026-07-16 ASL65W ARN → BEG Jul 16, 18:50 UTCJul 16, 21:05 UTC2h 15m
2026-07-16 ASL82Y BEG → ARN Jul 16, 15:25 UTCJul 16, 17:35 UTC2h 10m
2026-07-15 ASL95T - Jul 15, 12:55 UTCJul 15, 14:15 UTC1h 20m
2026-07-15 ASL15F BEG → PMO Jul 15, 10:10 UTCJul 15, 11:35 UTC1h 25m
2026-07-15 ASL41B - Jul 15, 06:55 UTCJul 15, 08:50 UTC1h 55m
2026-07-15 ASL45E BEG → AYT Jul 15, 03:10 UTCJul 15, 04:50 UTC1h 40m
2026-07-14 ASL17H LIS → BEG Jul 14, 15:55 UTCJul 14, 18:55 UTC3h 0m
2026-07-14 ASL53X BEG → LIS Jul 14, 10:35 UTCJul 14, 14:15 UTC3h 40m
2026-07-14 ASL89A - Jul 14, 06:20 UTCJul 14, 08:10 UTC1h 50m
2026-07-14 ASL37E BEG → AYT Jul 14, 03:10 UTCJul 14, 04:50 UTC1h 40m
2026-07-13 ASL15M - Jul 13, 18:50 UTCJul 13, 21:25 UTC2h 35m
2026-07-13 ASL53L BEG → MAD Jul 13, 14:10 UTCJul 13, 17:15 UTC3h 5m
2026-07-13 ASL99L - Jul 13, 12:20 UTCJul 13, 12:45 UTC25m
2026-07-13 ASL52N - Jul 13, 10:30 UTCJul 13, 10:50 UTC20m
2026-07-13 ASL81K - Jul 13, 06:50 UTCJul 13, 07:20 UTC30m
2026-07-13 ASL84H - Jul 13, 05:15 UTCJul 13, 05:35 UTC20m
2026-07-12 ASL30L - Jul 12, 20:15 UTCJul 12, 20:40 UTC25m
2026-07-12 ASL24M - Jul 12, 18:40 UTCJul 12, 19:01 UTC20m
2026-07-12 ASL22Q TIV → BEG Jul 12, 17:20 UTCJul 12, 17:45 UTC25m
2026-07-12 ASL30D SKP → BEG Jul 12, 15:30 UTCJul 12, 15:55 UTC25m
2026-07-11 ASL9471 MIR → BEG Jul 11, 19:15 UTCJul 11, 21:05 UTC1h 50m
2026-07-11 ASL9472 - Jul 11, 16:25 UTCJul 11, 18:10 UTC1h 45m
2026-07-11 ASL9473 - Jul 11, 13:20 UTCJul 11, 14:55 UTC1h 35m
2026-07-11 ASL9470 BEG → MIR Jul 11, 10:35 UTCJul 11, 12:35 UTC2h 0m
2026-07-11 ASL44B - Jul 11, 06:50 UTCJul 11, 08:50 UTC2h 0m
2026-07-11 ASL35B BEG → AYT Jul 11, 03:20 UTCJul 11, 05:15 UTC1h 55m
2026-07-10 ASL9975 MIR → BEG Jul 10, 22:05 UTCJul 10, 23:45 UTC1h 40m
2026-07-10 ASL9974 - Jul 10, 19:05 UTCJul 10, 20:50 UTC1h 45m
2026-07-10 ASL75J - Jul 10, 17:30 UTCJul 10, 17:55 UTC25m
2026-07-10 ASL64X - Jul 10, 15:55 UTCJul 10, 16:15 UTC20m
2026-07-10 ASL69A - Jul 10, 13:15 UTCJul 10, 14:35 UTC1h 20m
2026-07-10 ASL31D - Jul 10, 10:00 UTCJul 10, 11:25 UTC1h 25m
2026-07-10 ASL9599 - Jul 10, 07:00 UTCJul 10, 08:45 UTC1h 45m
2026-07-10 ASL9598 - Jul 10, 03:20 UTCJul 10, 05:00 UTC1h 40m
2026-07-10 ASL135 - Jul 10, 00:20 UTCJul 10, 00:30 UTC10m
2026-07-09 ASL135 - Jul 9, 21:55 UTCJul 9, 22:05 UTC10m
2026-07-09 ASL134 - Jul 9, 17:25 UTCJul 9, 19:30 UTC2h 5m
2026-07-08 ASL9475 MIR → BEG Jul 8, 19:35 UTCJul 8, 21:30 UTC1h 55m
2026-07-08 ASL9474 - Jul 8, 16:55 UTCJul 8, 18:35 UTC1h 40m
2026-07-08 ASL95T PMO → BEG Jul 8, 13:50 UTCJul 8, 15:15 UTC1h 25m
2026-07-08 ASL15F BEG → PMO Jul 8, 10:05 UTCJul 8, 11:25 UTC1h 20m
2026-07-08 ASL9531 - Jul 8, 06:45 UTCJul 8, 08:15 UTC1h 30m

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

Mode-S 4C01F3 frequently asked

What is Mode-S code 4C01F3?
4C01F3 is an ICAO 24-bit transponder address. Allocated to Serbia. Assigned to YU-APT.
Where is Mode-S 4C01F3 registered?
Mode-S code 4C01F3 is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C01F3 broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4C01F3, octal 23000763, decimal 4,981,235.
What flights does 4C01F3 operate?
Mode-S 4C01F3 has broadcast 20 distinct callsigns, including ASL134, ASL132, ASL133, ASL135, ASL63H.