sensors Mode-S transponder

AE4CF9

ICAO 24-bit transponder address

Currently assigned to 10-27025 · Alenia C-27J Spartan

Hex
AE4CF9
Octal
53446371
Decimal
11,422,969
Tail
10-27025
Type
C27J
No current signal · last broadcast 13h ago
Flights observed
12
Distinct callsigns
4
Country
-
Last broadcast
13h ago

Last known position

Most recent position reported by Mode-S AE4CF9.

Callsign history 4 distinct

Callsign Airline Flights Last seen
GECKO77 - 6 2026-06-02
GECKO31 - 3 2026-05-13
GECKO13 - 2 2026-05-13
GECKO71 - 1 2026-04-23

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-06-02 GECKO77 - Jun 2, 16:35 UTCJun 2, 17:30 UTC55m
2026-06-02 GECKO77 - Jun 2, 15:05 UTCJun 2, 15:55 UTC50m
2026-06-02 GECKO77 - Jun 2, 12:55 UTCJun 2, 14:25 UTC1h 30m
2026-06-01 GECKO77 - Jun 1, 13:50 UTCJun 1, 15:55 UTC2h 5m
2026-05-14 GECKO77 - May 14, 00:55 UTCMay 14, 01:55 UTC1h 0m
2026-05-13 GECKO77 - May 13, 23:15 UTCMay 14, 00:10 UTC55m
2026-05-13 GECKO31 - May 13, 15:20 UTCMay 13, 17:20 UTC2h 0m
2026-05-13 GECKO13 - May 13, 00:15 UTCMay 13, 00:25 UTC10m
2026-05-04 GECKO31 - May 4, 19:20 UTCMay 4, 19:30 UTC10m
2026-05-04 GECKO31 - May 4, 15:10 UTCMay 4, 15:20 UTC10m
2026-04-30 GECKO13 - Apr 30, 22:05 UTCMay 1, 00:30 UTC2h 25m
2026-04-23 GECKO71 - Apr 23, 16:10 UTCApr 23, 17:45 UTC1h 34m

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 10-27025 page for operator, model, and routing details .

Mode-S AE4CF9 frequently asked

What is Mode-S code AE4CF9?
AE4CF9 is an ICAO 24-bit transponder address. Assigned to 10-27025.
Is AE4CF9 broadcasting right now?
No active broadcast right now. Last signal was 13h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AE4CF9, octal 53446371, decimal 11,422,969.
What flights does AE4CF9 operate?
Mode-S AE4CF9 has broadcast 4 distinct callsigns, including GECKO77, GECKO31, GECKO13, GECKO71.