Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

4C0243

ICAO 24-bit transponder address · allocated to Serbia

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

Hex
4C0243
Octal
23001103
Decimal
4,981,315
Country
RS
Tail
YU-ASD
Type
AT76
No current signal · last broadcast Jul 26, 20:10 UTC
Flights observed
554
Distinct callsigns
20
Country
RS
Last broadcast
Jul 26, 20:10 UTC

Last known position

Most recent position reported by Mode-S 4C0243.

Country allocation

The ICAO 24-bit address 4C0243 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
ASL72L Spurling Aviation 16 2026-07-20
ASL10N Spurling Aviation 16 2026-07-20
ASL45T Spurling Aviation 15 2026-07-24
ASL37Z - 15 2026-07-24
ASL31Q - 15 2026-07-21
ASL81C Spurling Aviation 12 2026-07-07
ASL80A - 12 2026-07-07
ASL77L - 12 2026-07-21
ASL74K Spurling Aviation 12 2026-07-25
ASL49H Spurling Aviation 12 2026-07-07
ASL44Q - 12 2026-07-07
ASL40Y Spurling Aviation 12 2026-07-25
ASL79Y - 11 2026-07-21
ASL47P Spurling Aviation 11 2026-07-17
ASL26X - 11 2026-07-17
ASL33K - 10 2026-07-21
ASL78U Spurling Aviation 9 2026-07-24
ASL18R Spurling Aviation 9 2026-07-24
ASL97E Spurling Aviation 8 2026-07-19
ASL96B Spurling Aviation 8 2026-07-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 ASL159 KRK → BEG Jul 26, 18:40 UTCJul 26, 20:05 UTC1h 25m
2026-07-26 ASL158 BEG → KRK Jul 26, 16:20 UTCJul 26, 17:45 UTC1h 25m
2026-07-26 ASL51D ZAG → BEG Jul 26, 13:25 UTCJul 26, 14:15 UTC50m
2026-07-26 ASL30J BEG → ZAG Jul 26, 11:25 UTCJul 26, 12:20 UTC55m
2026-07-26 ASL59L BRI → BEG Jul 26, 08:20 UTCJul 26, 09:35 UTC1h 15m
2026-07-26 ASL83D BEG → BRI Jul 26, 05:30 UTCJul 26, 06:45 UTC1h 16m
2026-07-25 ASL61J BEG → TIV Jul 25, 13:10 UTCJul 25, 14:20 UTC1h 10m
2026-07-25 ASL77B BEG → BRU Jul 25, 11:05 UTCJul 25, 12:25 UTC1h 20m
2026-07-25 ASL40Y PUY → BEG Jul 25, 08:50 UTCJul 25, 10:00 UTC1h 10m
2026-07-25 ASL74K BEG → AMS Jul 25, 06:05 UTCJul 25, 07:20 UTC1h 15m
2026-07-25 ASL12E BEG → OPO Jul 25, 01:35 UTCJul 25, 02:50 UTC1h 15m
2026-07-24 ASL24B BER → BEG Jul 24, 23:25 UTCJul 25, 00:40 UTC1h 15m
2026-07-24 ASL37Z VIE → BEG Jul 24, 19:10 UTCJul 24, 20:10 UTC1h 0m
2026-07-24 ASL45T BEG → VIE Jul 24, 16:45 UTCJul 24, 17:55 UTC1h 10m
2026-07-24 ASL32P BEG → LCA Jul 24, 14:45 UTCJul 24, 15:25 UTC40m
2026-07-24 ASL38Y - Jul 24, 12:10 UTCJul 24, 12:45 UTC35m
2026-07-24 ASL78U PRG → BEG Jul 24, 08:50 UTCJul 24, 10:35 UTC1h 45m
2026-07-24 ASL18R BEG → PRG Jul 24, 04:55 UTCJul 24, 06:35 UTC1h 40m
2026-07-24 ASL96B BEG → BLQ Jul 24, 02:30 UTCJul 24, 03:05 UTC35m
2026-07-23 ASL59D - Jul 23, 23:15 UTCJul 23, 23:50 UTC35m
2026-07-23 ASL61J BEG → TIV Jul 23, 13:20 UTCJul 23, 14:30 UTC1h 10m
2026-07-23 ASL77B BEG → BRU Jul 23, 10:50 UTCJul 23, 12:00 UTC1h 10m
2026-07-23 ASL40Y - Jul 23, 08:05 UTCJul 23, 09:20 UTC1h 15m
2026-07-23 ASL74K - Jul 23, 05:45 UTCJul 23, 07:05 UTC1h 20m
2026-07-23 ASL12E BEG → OPO Jul 23, 01:30 UTCJul 23, 02:50 UTC1h 20m
2026-07-22 ASL24B BEG → SKG Jul 22, 22:55 UTCJul 23, 00:10 UTC1h 15m
2026-07-22 ASL40Y - Jul 22, 13:15 UTCJul 22, 14:30 UTC1h 15m
2026-07-22 ASL74K - Jul 22, 11:10 UTCJul 22, 12:15 UTC1h 5m
2026-07-21 ASL33K - Jul 21, 13:50 UTCJul 21, 14:30 UTC40m
2026-07-21 ASL79Y - Jul 21, 11:45 UTCJul 21, 12:20 UTC35m
2026-07-21 ASL31Q - Jul 21, 07:30 UTCJul 21, 08:30 UTC1h 0m
2026-07-21 ASL77L BEG → LJU Jul 21, 05:30 UTCJul 21, 06:45 UTC1h 15m
2026-07-20 ASL10N LJU → BEG Jul 20, 19:05 UTCJul 20, 20:05 UTC1h 0m
2026-07-20 ASL72L BEG → TIA Jul 20, 17:05 UTCJul 20, 18:20 UTC1h 15m
2026-07-20 ASL88A FRA → BEG Jul 20, 14:10 UTCJul 20, 15:10 UTC1h 0m
2026-07-20 ASL16F INI → CGN Jul 20, 11:50 UTCJul 20, 12:50 UTC1h 0m
2026-07-20 ASL78U PRG → BEG Jul 20, 07:40 UTCJul 20, 09:20 UTC1h 40m
2026-07-20 ASL18R BEG → PRG Jul 20, 04:45 UTCJul 20, 06:40 UTC1h 55m
2026-07-20 ASL12E SKG → BEG Jul 20, 01:40 UTCJul 20, 03:00 UTC1h 20m
2026-07-19 ASL24B BEG → SKG Jul 19, 23:30 UTCJul 20, 00:45 UTC1h 15m
2026-07-19 ASL40Y - Jul 19, 19:05 UTCJul 19, 20:20 UTC1h 15m
2026-07-19 ASL74K - Jul 19, 16:55 UTCJul 19, 18:15 UTC1h 20m
2026-07-19 ASL97E BUD → BEG Jul 19, 14:50 UTCJul 19, 15:45 UTC55m
2026-07-19 ASL72Q BEG → BUD Jul 19, 12:40 UTCJul 19, 13:35 UTC55m
2026-07-19 ASL48F - Jul 19, 10:25 UTCJul 19, 11:00 UTC35m
2026-07-19 ASL40T - Jul 19, 08:05 UTCJul 19, 09:30 UTC1h 25m
2026-07-19 ASL14D - Jul 19, 05:30 UTCJul 19, 06:55 UTC1h 25m
2026-07-18 ASL93T - Jul 18, 19:15 UTCJul 18, 20:30 UTC1h 15m
2026-07-18 ASL26T INI → LJU Jul 18, 17:00 UTCJul 18, 18:30 UTC1h 30m
2026-07-18 ASL99C BEG → TBS Jul 18, 15:35 UTCJul 18, 16:00 UTC25m

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

Mode-S 4C0243 frequently asked

What is Mode-S code 4C0243?
4C0243 is an ICAO 24-bit transponder address. Allocated to Serbia. Assigned to YU-ASD.
Where is Mode-S 4C0243 registered?
Mode-S code 4C0243 is allocated to Serbia (RS). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4C0243 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 20:10 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4C0243, octal 23001103, decimal 4,981,315.
What flights does 4C0243 operate?
Mode-S 4C0243 has broadcast 20 distinct callsigns, including ASL72L, ASL10N, ASL45T, ASL37Z, ASL31Q.