sensors Mode-S transponder

4A5DF7

ICAO 24-bit transponder address · allocated to Romania

Currently assigned to YR-WOW · AIRBUS A-321neo

Hex
4A5DF7
Octal
22456767
Decimal
4,873,719
Country
RO
Tail
YR-WOW
Type
A21N
No current signal · last broadcast 1d ago
Flights observed
5
Distinct callsigns
2
Country
RO
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 4A5DF7.

Country allocation

The ICAO 24-bit address 4A5DF7 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 2 distinct

Callsign Airline Flights Last seen
HYS263 HiSky Europe 3 2026-04-13
HYS264 - 2 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 HYS264 - Apr 13, 12:20 UTCApr 13, 14:30 UTC2h 10m
2026-04-13 HYS264 - Apr 13, 11:50 UTCApr 13, 12:15 UTC25m
2026-04-13 HYS263 OTP → BCN Apr 13, 08:20 UTCApr 13, 10:10 UTC1h 50m
2026-04-13 HYS263 OTP → BCN Apr 13, 07:55 UTCApr 13, 10:10 UTC2h 15m
2026-04-13 HYS263 OTP → BCN Apr 13, 07:25 UTCApr 13, 08:15 UTC50m

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

Mode-S 4A5DF7 frequently asked

What is Mode-S code 4A5DF7?
4A5DF7 is an ICAO 24-bit transponder address. Allocated to Romania. Assigned to YR-WOW.
Where is Mode-S 4A5DF7 registered?
Mode-S code 4A5DF7 is allocated to Romania (RO). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4A5DF7 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 4A5DF7, octal 22456767, decimal 4,873,719.
What flights does 4A5DF7 operate?
Mode-S 4A5DF7 has broadcast 2 distinct callsigns, including HYS263, HYS264.