sensors Mode-S transponder

4CAC0B

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-KDD · AIRBUS A-321neo

Hex
4CAC0B
Octal
23126013
Decimal
5,024,779
Country
IE
Tail
EI-KDD
Type
A21N
No current signal · last broadcast 14h ago
Flights observed
3
Distinct callsigns
2
Country
IE
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S 4CAC0B.

Country allocation

The ICAO 24-bit address 4CAC0B 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
KZR557 - 2 2026-04-14
KZR558 Air Astana 1 2026-04-14

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-14 KZR558 SSH → NQZ Apr 14, 10:10 UTCApr 14, 11:05 UTC55m
2026-04-14 KZR557 - Apr 14, 07:10 UTCApr 14, 07:50 UTC40m
2026-04-14 KZR557 - Apr 14, 05:15 UTCApr 14, 07:10 UTC1h 55m

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

Mode-S 4CAC0B frequently asked

What is Mode-S code 4CAC0B?
4CAC0B is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-KDD.
Where is Mode-S 4CAC0B registered?
Mode-S code 4CAC0B is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAC0B broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAC0B, octal 23126013, decimal 5,024,779.
What flights does 4CAC0B operate?
Mode-S 4CAC0B has broadcast 2 distinct callsigns, including KZR557, KZR558.