Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

4D249A

ICAO 24-bit transponder address

Hex
4D249A
Octal
23222232
Decimal
5,055,642
No current signal · last broadcast 28d ago
Flights observed
1
Distinct callsigns
1
Country
-
Last broadcast
28d ago

Last known position

Most recent position reported by Mode-S 4D249A.

Callsign history 1 distinct

Callsign Airline Flights Last seen
WZZ1319 Wizz Air 1 2026-06-25

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-06-25 WZZ1319 TGD → WAW Jun 25, 21:25 UTCJun 25, 21:35 UTC10m

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 4D249A frequently asked

What is Mode-S code 4D249A?
4D249A is an ICAO 24-bit transponder address.
Is 4D249A broadcasting right now?
No active broadcast right now. Last signal was 28d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D249A, octal 23222232, decimal 5,055,642.
What flights does 4D249A operate?
Mode-S 4D249A has broadcast 1 distinct callsign, including WZZ1319.