sensors Mode-S transponder

4D2525

ICAO 24-bit transponder address

Currently assigned to 9H-LYR

Hex
4D2525
Octal
23222445
Decimal
5,055,781
Tail
9H-LYR
Type
B38M
No current signal · last broadcast Jul 15, 13:00 UTC
Flights observed
1
Distinct callsigns
1
Country
-
Last broadcast
Jul 15, 13:00 UTC

Last known position

Most recent position reported by Mode-S 4D2525.

Callsign history 1 distinct

Callsign Airline Flights Last seen
WZZ9588 - 1 2026-07-15

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-07-15 WZZ9588 - Jul 15, 12:45 UTCJul 15, 13:00 UTC15m

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

Mode-S 4D2525 frequently asked

What is Mode-S code 4D2525?
4D2525 is an ICAO 24-bit transponder address. Assigned to 9H-LYR.
Is 4D2525 broadcasting right now?
No active broadcast right now. Last signal was Jul 15, 13:00 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D2525, octal 23222445, decimal 5,055,781.
What flights does 4D2525 operate?
Mode-S 4D2525 has broadcast 1 distinct callsign, including WZZ9588.