sensors Mode-S transponder

4C0240

ICAO 24-bit transponder address · allocated to Serbia

Currently assigned to YU-ASA · ATR-72-600

Hex
4C0240
Octal
23001100
Decimal
4,981,312
Country
RS
Tail
YU-ASA
Type
AT76
No current signal · last broadcast 2h ago
Flights observed
17
Distinct callsigns
13
Country
RS
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 4C0240.

Country allocation

The ICAO 24-bit address 4C0240 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 13 distinct

Recent flights last 17

DateFlightRouteTakeoffLandingDuration
2026-05-20 ASL72L BEG → TIA May 20, 16:50 UTCMay 20, 17:55 UTC1h 5m
2026-05-20 ASL97E BUD → BEG May 20, 13:35 UTCMay 20, 14:35 UTC1h 0m
2026-05-20 ASL72Q BEG → BUD May 20, 11:40 UTCMay 20, 12:30 UTC50m
2026-05-19 ASL97E BUD → BEG May 19, 13:30 UTCMay 19, 14:25 UTC55m
2026-05-19 ASL72Q BEG → BUD May 19, 11:50 UTCMay 19, 12:45 UTC55m
2026-05-19 ASL45B IST → BEG May 19, 08:15 UTCMay 19, 09:10 UTC55m
2026-05-19 ASL92Z BEG → BRI May 19, 06:00 UTCMay 19, 06:50 UTC50m
2026-05-19 ASL33J INI → BEG May 19, 02:10 UTCMay 19, 02:45 UTC35m
2026-05-18 ASL47G BEG → SKP May 18, 23:00 UTCMay 18, 23:35 UTC35m
2026-05-18 ASL37Z VIE → BEG May 18, 19:25 UTCMay 18, 20:30 UTC1h 5m
2026-05-18 ASL45T BEG → VIE May 18, 17:25 UTCMay 18, 18:35 UTC1h 9m
2026-05-18 ASL32P BEG → LCA May 18, 13:50 UTCMay 18, 14:40 UTC50m
2026-05-18 ASL38Y - May 18, 11:30 UTCMay 18, 12:25 UTC55m
2026-05-18 ASL45B IST → BEG May 18, 07:50 UTCMay 18, 08:45 UTC55m
2026-05-18 ASL92Z BEG → BRI May 18, 06:05 UTCMay 18, 06:55 UTC50m
2026-05-17 ASL4041 IST → BEG May 17, 14:10 UTCMay 17, 14:55 UTC45m
2026-05-13 ASL4040 BEG → SOF May 13, 06:20 UTCMay 13, 06:50 UTC30m

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

Mode-S 4C0240 frequently asked

What is Mode-S code 4C0240?
4C0240 is an ICAO 24-bit transponder address. Allocated to Serbia. Assigned to YU-ASA.
Where is Mode-S 4C0240 registered?
Mode-S code 4C0240 is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C0240 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 4C0240, octal 23001100, decimal 4,981,312.
What flights does 4C0240 operate?
Mode-S 4C0240 has broadcast 13 distinct callsigns, including ASL97E, ASL92Z, ASL72Q, ASL45B, ASL72L.