sensors Mode-S transponder

4C01F4

ICAO 24-bit transponder address · allocated to Serbia

Hex
4C01F4
Octal
23000764
Decimal
4,981,236
Country
RS
Broadcasting now · callsign ASL53X · 3,850 ft
Flights observed
48
Distinct callsigns
20
Country
RS
Last broadcast
Jul 26, 21:15 UTC

Current position

4C01F4 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4C01F4 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
ASL93X Spurling Aviation 3 2026-07-25
ASL37R - 3 2026-07-25
ASL53X Spurling Aviation 2 2026-07-24
ASL30L Spurling Aviation 2 2026-07-26
ASL24M - 2 2026-07-26
ASL17H - 2 2026-07-24
ASL99L - 1 2026-07-18
ASL97Q - 1 2026-07-21
ASL9432 - 1 2026-07-22
ASL9431 - 1 2026-07-25
ASL9430 - 1 2026-07-25
ASL93N - 1 2026-07-23
ASL86T - 1 2026-07-20
ASL84H - 1 2026-07-18
ASL81K - 1 2026-07-18
ASL75J Spurling Aviation 1 2026-07-23
ASL73B Spurling Aviation 1 2026-07-25
ASL71Z Spurling Aviation 1 2026-07-26
ASL71H - 1 2026-07-20
ASL71G - 1 2026-07-20

Recent flights last 48

DateFlightRouteTakeoffLandingDuration
2026-07-26 ASL30L TGD → BEG Jul 26, 20:55 UTCJul 26, 21:15 UTC20m
2026-07-26 ASL24M - Jul 26, 18:55 UTCJul 26, 19:05 UTC10m
2026-07-26 ASL22Q TIV → BEG Jul 26, 17:20 UTCJul 26, 17:35 UTC15m
2026-07-26 ASL30D SKP → BEG Jul 26, 15:20 UTCJul 26, 15:30 UTC10m
2026-07-26 ASL71Z BEG → LYS Jul 26, 06:35 UTCJul 26, 08:40 UTC2h 5m
2026-07-26 ASL55U - Jul 26, 03:15 UTCJul 26, 05:00 UTC1h 45m
2026-07-25 ASL37R - Jul 25, 18:50 UTCJul 25, 19:10 UTC20m
2026-07-25 ASL93X BEG → TGD Jul 25, 16:55 UTCJul 25, 17:05 UTC10m
2026-07-25 ASL73B TGD → BEG Jul 25, 15:00 UTCJul 25, 15:30 UTC30m
2026-07-25 ASL32A BEG → TIV Jul 25, 13:10 UTCJul 25, 13:20 UTC10m
2026-07-25 ASL9431 - Jul 25, 08:20 UTCJul 25, 10:00 UTC1h 40m
2026-07-25 ASL9430 - Jul 25, 04:35 UTCJul 25, 05:55 UTC1h 20m
2026-07-25 ASL427 IST → BEG Jul 25, 01:50 UTCJul 25, 03:00 UTC1h 10m
2026-07-24 ASL426 BEG → IST Jul 24, 23:15 UTCJul 25, 00:25 UTC1h 10m
2026-07-24 ASL17H LIS → BEG Jul 24, 17:15 UTCJul 24, 20:20 UTC3h 5m
2026-07-24 ASL53X BEG → LIS Jul 24, 11:40 UTCJul 24, 15:20 UTC3h 40m
2026-07-24 ASL27J BEG → GOT Jul 24, 08:25 UTCJul 24, 10:20 UTC1h 55m
2026-07-24 ASL22A - Jul 24, 03:15 UTCJul 24, 05:00 UTC1h 45m
2026-07-23 ASL75J SOF → BEG Jul 23, 17:45 UTCJul 23, 18:10 UTC25m
2026-07-23 ASL64X PRG → BEG Jul 23, 16:00 UTCJul 23, 16:20 UTC20m
2026-07-23 ASL93N RHO → BEG Jul 23, 12:55 UTCJul 23, 14:35 UTC1h 40m
2026-07-23 ASL36V BEG → RHO Jul 23, 10:10 UTCJul 23, 11:45 UTC1h 35m
2026-07-23 ASL33W - Jul 23, 06:25 UTCJul 23, 08:15 UTC1h 50m
2026-07-23 ASL58C LCA → BEG Jul 23, 03:10 UTCJul 23, 05:00 UTC1h 50m
2026-07-22 ASL16J CPH → BEG Jul 22, 19:40 UTCJul 22, 21:25 UTC1h 45m
2026-07-22 ASL19H BEG → CPH Jul 22, 16:35 UTCJul 22, 18:35 UTC2h 0m
2026-07-22 ASL37R - Jul 22, 14:40 UTCJul 22, 15:15 UTC35m
2026-07-22 ASL93X - Jul 22, 12:00 UTCJul 22, 12:20 UTC20m
2026-07-22 ASL9432 - Jul 22, 04:35 UTCJul 22, 05:25 UTC50m
2026-07-21 ASL17H LIS → BEG Jul 21, 16:40 UTCJul 21, 19:45 UTC3h 5m
2026-07-21 ASL53X BEG → LIS Jul 21, 11:05 UTCJul 21, 15:05 UTC4h 0m
2026-07-21 ASL56H - Jul 21, 06:35 UTCJul 21, 08:35 UTC2h 0m
2026-07-21 ASL97Q BEG → AYT Jul 21, 03:20 UTCJul 21, 05:15 UTC1h 55m
2026-07-20 ASL30L - Jul 20, 22:10 UTCJul 20, 22:40 UTC30m
2026-07-20 ASL24M - Jul 20, 20:45 UTCJul 20, 21:05 UTC20m
2026-07-20 ASL47E - Jul 20, 17:00 UTCJul 20, 19:20 UTC2h 20m
2026-07-20 ASL71H - Jul 20, 13:20 UTCJul 20, 15:30 UTC2h 10m
2026-07-20 ASL71G - Jul 20, 09:20 UTCJul 20, 11:30 UTC2h 10m
2026-07-20 ASL86T - Jul 20, 05:20 UTCJul 20, 07:40 UTC2h 20m
2026-07-19 ASL10A BEG → ZRH Jul 19, 13:10 UTCJul 19, 15:15 UTC2h 5m
2026-07-19 ASL12H BEG → LHR Jul 19, 08:45 UTCJul 19, 11:25 UTC2h 40m
2026-07-18 ASL99L - Jul 18, 11:00 UTCJul 18, 11:35 UTC35m
2026-07-18 ASL52N BEG → TIV Jul 18, 08:55 UTCJul 18, 09:20 UTC25m
2026-07-18 ASL81K - Jul 18, 06:55 UTCJul 18, 07:20 UTC25m
2026-07-18 ASL84H - Jul 18, 05:10 UTCJul 18, 05:35 UTC25m
2026-07-17 ASL37R - Jul 17, 17:55 UTCJul 17, 18:25 UTC30m
2026-07-17 ASL93X - Jul 17, 15:20 UTCJul 17, 15:44 UTC25m
2026-07-14 ASL4021 - Jul 14, 09:15 UTCJul 14, 10:55 UTC1h 40m

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 4C01F4 frequently asked

What is Mode-S code 4C01F4?
4C01F4 is an ICAO 24-bit transponder address. Allocated to Serbia.
Where is Mode-S 4C01F4 registered?
Mode-S code 4C01F4 is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C01F4 broadcasting right now?
Yes. Mode-S 4C01F4 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4C01F4, octal 23000764, decimal 4,981,236.
What flights does 4C01F4 operate?
Mode-S 4C01F4 has broadcast 20 distinct callsigns, including ASL93X, ASL37R, ASL53X, ASL30L, ASL24M.