sensors Mode-S transponder

4C0241

ICAO 24-bit transponder address · allocated to Serbia

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

Hex
4C0241
Octal
23001101
Decimal
4,981,313
Country
RS
Tail
YU-ASB
Type
AT76
No current signal · last broadcast 1d ago
Flights observed
12
Distinct callsigns
10
Country
RS
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 4C0241.

Country allocation

The ICAO 24-bit address 4C0241 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 10 distinct

Callsign Airline Flights Last seen
ASL79Y - 2 2026-04-13
ASL34H Spurling Aviation 2 2026-04-13
ASL72L - 1 2026-04-12
ASL63P - 1 2026-04-13
ASL57F - 1 2026-04-13
ASL33K - 1 2026-04-13
ASL28J - 1 2026-04-13
ASL15A - 1 2026-04-13
ASL10Q - 1 2026-04-13
ASL10N - 1 2026-04-12

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-04-13 ASL28J - Apr 13, 17:10 UTCApr 13, 17:40 UTC30m
2026-04-13 ASL63P - Apr 13, 15:50 UTCApr 13, 16:15 UTC25m
2026-04-13 ASL33K - Apr 13, 14:00 UTCApr 13, 14:45 UTC45m
2026-04-13 ASL79Y - Apr 13, 12:20 UTCApr 13, 12:35 UTC15m
2026-04-13 ASL79Y - Apr 13, 11:55 UTCApr 13, 12:15 UTC20m
2026-04-13 ASL10Q BUD → BEG Apr 13, 09:45 UTCApr 13, 10:30 UTC45m
2026-04-13 ASL34H MAD → BEG Apr 13, 08:20 UTCApr 13, 08:50 UTC30m
2026-04-13 ASL34H MAD → BEG Apr 13, 07:55 UTCApr 13, 08:15 UTC20m
2026-04-13 ASL15A - Apr 13, 06:25 UTCApr 13, 06:55 UTC30m
2026-04-13 ASL57F - Apr 13, 04:40 UTCApr 13, 05:15 UTC35m
2026-04-12 ASL10N - Apr 12, 18:35 UTCApr 12, 19:40 UTC1h 5m
2026-04-12 ASL72L - Apr 12, 17:15 UTCApr 12, 17:50 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 YU-ASB page for operator, model, and routing details .

Mode-S 4C0241 frequently asked

What is Mode-S code 4C0241?
4C0241 is an ICAO 24-bit transponder address. Allocated to Serbia. Assigned to YU-ASB.
Where is Mode-S 4C0241 registered?
Mode-S code 4C0241 is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C0241 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4C0241, octal 23001101, decimal 4,981,313.
What flights does 4C0241 operate?
Mode-S 4C0241 has broadcast 10 distinct callsigns, including ASL79Y, ASL34H, ASL72L, ASL63P, ASL57F.