sensors Mode-S transponder

4CAEF1

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-KIE · AIRBUS A-320neo

Hex
4CAEF1
Octal
23127361
Decimal
5,025,521
Country
IE
Tail
EI-KIE
Type
A20N
No current signal · last broadcast 10d ago
Flights observed
4
Distinct callsigns
2
Country
IE
Last broadcast
10d ago

Last known position

Most recent position reported by Mode-S 4CAEF1.

Country allocation

The ICAO 24-bit address 4CAEF1 falls within the block assigned to Ireland (IE) by ICAO Annex 10, Volume III. Every aircraft registered in Ireland receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 2 distinct

Callsign Airline Flights Last seen
KZR869 Air Astana 3 2026-05-19
KZR870 Air Astana 1 2026-05-19

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-05-19 KZR870 IST → GUW May 19, 11:00 UTCMay 19, 13:05 UTC2h 5m
2026-05-19 KZR869 GUW → IST May 19, 08:05 UTCMay 19, 08:15 UTC10m
2026-05-19 KZR869 GUW → IST May 19, 06:10 UTCMay 19, 07:15 UTC1h 5m
2026-05-19 KZR869 GUW → IST May 19, 05:05 UTCMay 19, 05:40 UTC35m

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 EI-KIE page for operator, model, and routing details .

Mode-S 4CAEF1 frequently asked

What is Mode-S code 4CAEF1?
4CAEF1 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-KIE.
Where is Mode-S 4CAEF1 registered?
Mode-S code 4CAEF1 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAEF1 broadcasting right now?
No active broadcast right now. Last signal was 10d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAEF1, octal 23127361, decimal 5,025,521.
What flights does 4CAEF1 operate?
Mode-S 4CAEF1 has broadcast 2 distinct callsigns, including KZR869, KZR870.