Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

AF4EE1

ICAO 24-bit transponder address

Hex
AF4EE1
Octal
53647341
Decimal
11,488,993
No current signal · last broadcast 17d ago
Flights observed
4
Distinct callsigns
1
Country
-
Last broadcast
17d ago

Last known position

Most recent position reported by Mode-S AF4EE1.

Callsign history 1 distinct

Callsign Airline Flights Last seen
KING348 - 4 2026-05-26

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-05-26 KING348 - May 26, 16:55 UTCMay 26, 19:10 UTC2h 15m
2026-05-22 KING348 - May 22, 14:10 UTCMay 22, 15:55 UTC1h 45m
2026-05-20 KING348 - May 20, 13:50 UTCMay 20, 15:20 UTC1h 30m
2026-05-15 KING348 - May 15, 17:05 UTCMay 15, 18:25 UTC1h 20m

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 AF4EE1 frequently asked

What is Mode-S code AF4EE1?
AF4EE1 is an ICAO 24-bit transponder address.
Is AF4EE1 broadcasting right now?
No active broadcast right now. Last signal was 17d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AF4EE1, octal 53647341, decimal 11,488,993.
What flights does AF4EE1 operate?
Mode-S AF4EE1 has broadcast 1 distinct callsign, including KING348.