sensors Mode-S transponder

4A3499

ICAO 24-bit transponder address · allocated to Romania

Currently assigned to YR-MDY · TECNAM P-2008

Hex
4A3499
Octal
22432231
Decimal
4,863,129
Country
RO
Tail
YR-MDY
Type
P208
No current signal · last broadcast 8d ago
Flights observed
35
Distinct callsigns
1
Country
RO
Last broadcast
8d ago

Last known position

Most recent position reported by Mode-S 4A3499.

Country allocation

The ICAO 24-bit address 4A3499 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
YRMDY - 35 2026-05-25

Recent flights last 35

DateFlightRouteTakeoffLandingDuration
2026-05-25 YRMDY - May 25, 07:10 UTCMay 25, 08:35 UTC1h 25m
2026-05-25 YRMDY - May 25, 06:15 UTCMay 25, 06:25 UTC10m
2026-05-25 YRMDY - May 25, 05:25 UTCMay 25, 05:40 UTC15m
2026-05-19 YRMDY - May 19, 08:50 UTCMay 19, 09:30 UTC40m
2026-05-19 YRMDY - May 19, 05:30 UTCMay 19, 07:45 UTC2h 15m
2026-05-15 YRMDY - May 15, 07:40 UTCMay 15, 09:10 UTC1h 30m
2026-05-15 YRMDY - May 15, 05:10 UTCMay 15, 07:00 UTC1h 50m
2026-05-13 YRMDY - May 13, 05:40 UTCMay 13, 07:30 UTC1h 50m
2026-04-28 YRMDY - Apr 28, 05:35 UTCApr 28, 06:00 UTC25m
2026-04-27 YRMDY - Apr 27, 09:15 UTCApr 27, 09:55 UTC40m
2026-04-27 YRMDY - Apr 27, 06:10 UTCApr 27, 06:50 UTC40m
2026-04-24 YRMDY - Apr 24, 09:25 UTCApr 24, 10:10 UTC45m
2026-04-24 YRMDY - Apr 24, 06:05 UTCApr 24, 06:50 UTC45m
2026-04-23 YRMDY - Apr 23, 13:15 UTCApr 23, 14:35 UTC1h 20m
2026-04-23 YRMDY - Apr 23, 10:01 UTCApr 23, 12:15 UTC2h 15m
2026-04-22 YRMDY - Apr 22, 10:40 UTCApr 22, 10:50 UTC10m
2026-04-22 YRMDY - Apr 22, 07:15 UTCApr 22, 08:50 UTC1h 35m
2026-04-22 YRMDY - Apr 22, 05:10 UTCApr 22, 06:20 UTC1h 10m
2026-04-21 YRMDY - Apr 21, 10:25 UTCApr 21, 11:20 UTC55m
2026-04-21 YRMDY - Apr 21, 05:05 UTCApr 21, 06:25 UTC1h 20m
2026-04-20 YRMDY - Apr 20, 09:30 UTCApr 20, 10:05 UTC35m
2026-04-20 YRMDY - Apr 20, 06:20 UTCApr 20, 07:05 UTC45m
2026-04-17 YRMDY - Apr 17, 11:20 UTCApr 17, 11:45 UTC25m
2026-04-17 YRMDY - Apr 17, 10:05 UTCApr 17, 11:15 UTC1h 10m
2026-04-17 YRMDY - Apr 17, 07:50 UTCApr 17, 08:20 UTC30m
2026-04-17 YRMDY - Apr 17, 06:40 UTCApr 17, 07:05 UTC25m
2026-04-17 YRMDY - Apr 17, 05:20 UTCApr 17, 06:10 UTC50m
2026-04-16 YRMDY - Apr 16, 11:25 UTCApr 16, 13:00 UTC1h 35m
2026-04-16 YRMDY - Apr 16, 09:10 UTCApr 16, 09:35 UTC25m
2026-04-16 YRMDY - Apr 16, 08:09 UTCApr 16, 09:05 UTC55m
2026-04-15 YRMDY - Apr 15, 11:55 UTCApr 15, 12:55 UTC1h 0m
2026-04-15 YRMDY - Apr 15, 10:15 UTCApr 15, 10:25 UTC10m
2026-04-15 YRMDY - Apr 15, 09:00 UTCApr 15, 09:35 UTC35m
2026-04-15 YRMDY - Apr 15, 07:10 UTCApr 15, 08:55 UTC1h 45m
2026-04-15 YRMDY - Apr 15, 05:20 UTCApr 15, 06:35 UTC1h 15m

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 YR-MDY page for operator, model, and routing details .

Mode-S 4A3499 frequently asked

What is Mode-S code 4A3499?
4A3499 is an ICAO 24-bit transponder address. Allocated to Romania. Assigned to YR-MDY.
Where is Mode-S 4A3499 registered?
Mode-S code 4A3499 is allocated to Romania (RO). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4A3499 broadcasting right now?
No active broadcast right now. Last signal was 8d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4A3499, octal 22432231, decimal 4,863,129.
What flights does 4A3499 operate?
Mode-S 4A3499 has broadcast 1 distinct callsign, including YRMDY.