sensors Mode-S transponder

4D2504

ICAO 24-bit transponder address

Currently assigned to 9H-VVS · BOEING 737 MAX 8

Hex
4D2504
Octal
23222404
Decimal
5,055,748
Tail
9H-VVS
Type
B38M
No current signal · last broadcast 39m ago
Flights observed
8
Distinct callsigns
8
Country
-
Last broadcast
39m ago

Last known position

Most recent position reported by Mode-S 4D2504.

Callsign history 8 distinct

Callsign Airline Flights Last seen
RYR81YQ Ryanair 1 2026-06-09
RYR7FJ Ryanair 1 2026-06-08
RYR76RK Ryanair 1 2026-06-09
RYR6FH Ryanair 1 2026-06-09
RYR69KF Ryanair 1 2026-06-09
RYR62EG Ryanair 1 2026-06-08
RYR628R Ryanair 1 2026-06-09
RYR459M Ryanair 1 2026-06-09

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-06-09 RYR81YQ DUB → OPO Jun 9, 19:15 UTCJun 9, 21:00 UTC1h 45m
2026-06-09 RYR6FH EDI → LIS Jun 9, 17:45 UTCJun 9, 18:35 UTC50m
2026-06-09 RYR69KF DUB → KIR Jun 9, 16:45 UTCJun 9, 17:05 UTC20m
2026-06-09 RYR628R RMU → DUB Jun 9, 12:55 UTCJun 9, 15:30 UTC2h 35m
2026-06-09 RYR76RK DUB → RMU Jun 9, 09:35 UTCJun 9, 12:00 UTC2h 25m
2026-06-09 RYR459M EDI → DUB Jun 9, 07:50 UTCJun 9, 08:30 UTC40m
2026-06-08 RYR7FJ SJJ → CRL Jun 8, 20:45 UTCJun 8, 23:35 UTC2h 50m
2026-06-08 RYR62EG EDI → AGP Jun 8, 16:40 UTCJun 8, 19:30 UTC2h 50m

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 9H-VVS page for operator, model, and routing details .

Mode-S 4D2504 frequently asked

What is Mode-S code 4D2504?
4D2504 is an ICAO 24-bit transponder address. Assigned to 9H-VVS.
Is 4D2504 broadcasting right now?
No active broadcast right now. Last signal was 39m ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D2504, octal 23222404, decimal 5,055,748.
What flights does 4D2504 operate?
Mode-S 4D2504 has broadcast 8 distinct callsigns, including RYR81YQ, RYR7FJ, RYR76RK, RYR6FH, RYR69KF.