sensors Mode-S transponder

4A3AF4

ICAO 24-bit transponder address · allocated to Romania

Hex
4A3AF4
Octal
22435364
Decimal
4,864,756
Country
RO
No current signal · last broadcast 3d ago
Flights observed
18
Distinct callsigns
1
Country
RO
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S 4A3AF4.

Country allocation

The ICAO 24-bit address 4A3AF4 falls within the block assigned to Romania (RO) by ICAO Annex 10, Volume III. Every aircraft registered in Romania 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 1 distinct

Callsign Airline Flights Last seen
YRNWT - 18 2026-05-30

Recent flights last 18

DateFlightRouteTakeoffLandingDuration
2026-05-30 YRNWT - May 30, 12:30 UTCMay 30, 13:15 UTC45m
2026-05-30 YRNWT - May 30, 11:10 UTCMay 30, 11:50 UTC40m
2026-05-30 YRNWT - May 30, 03:55 UTCMay 30, 05:40 UTC1h 45m
2026-05-24 YRNWT - May 24, 11:55 UTCMay 24, 13:20 UTC1h 25m
2026-05-24 YRNWT - May 24, 06:35 UTCMay 24, 08:05 UTC1h 30m
2026-05-16 YRNWT - May 16, 09:31 UTCMay 16, 10:01 UTC30m
2026-05-16 YRNWT - May 16, 06:35 UTCMay 16, 07:20 UTC45m
2026-05-08 YRNWT - May 8, 13:05 UTCMay 8, 13:55 UTC50m
2026-05-08 YRNWT - May 8, 11:49 UTCMay 8, 12:14 UTC25m
2026-05-03 YRNWT - May 3, 13:00 UTCMay 3, 13:10 UTC10m
2026-05-03 YRNWT - May 3, 11:15 UTCMay 3, 11:30 UTC15m
2026-05-02 YRNWT - May 2, 08:25 UTCMay 2, 09:30 UTC1h 5m
2026-04-25 YRNWT - Apr 25, 11:35 UTCApr 25, 12:15 UTC40m
2026-04-25 YRNWT - Apr 25, 10:00 UTCApr 25, 11:05 UTC1h 5m
2026-04-18 YRNWT - Apr 18, 10:30 UTCApr 18, 11:10 UTC40m
2026-04-17 YRNWT - Apr 17, 17:40 UTCApr 17, 18:40 UTC1h 0m
2026-04-16 YRNWT - Apr 16, 13:15 UTCApr 16, 14:05 UTC50m
2026-04-16 YRNWT - Apr 16, 12:45 UTCApr 16, 13:05 UTC20m

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 4A3AF4 frequently asked

What is Mode-S code 4A3AF4?
4A3AF4 is an ICAO 24-bit transponder address. Allocated to Romania.
Where is Mode-S 4A3AF4 registered?
Mode-S code 4A3AF4 is allocated to Romania (RO). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4A3AF4 broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4A3AF4, octal 22435364, decimal 4,864,756.
What flights does 4A3AF4 operate?
Mode-S 4A3AF4 has broadcast 1 distinct callsign, including YRNWT.