sensors Mode-S transponder

4CAAF1

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-EIK · AIRBUS A-330-300

Hex
4CAAF1
Octal
23125361
Decimal
5,024,497
Country
IE
Tail
EI-EIK
Type
A333
Photo of EI-EIK
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
4
Country
IE
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 4CAAF1.

Country allocation

The ICAO 24-bit address 4CAAF1 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 4 distinct

Callsign Airline Flights Last seen
EIN1EN - 3 2026-04-13
EIN1MN Aer Lingus 1 2026-04-13
EIN123 - 1 2026-04-12
EIN122 - 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 EIN1MN YYZ → DUB Apr 13, 22:05 UTCApr 13, 23:45 UTC1h 40m
2026-04-13 EIN1EN - Apr 13, 19:50 UTCApr 13, 19:55 UTC5m
2026-04-13 EIN1EN - Apr 13, 17:55 UTCApr 13, 19:55 UTC2h 0m
2026-04-13 EIN1EN - Apr 13, 12:50 UTCApr 13, 13:40 UTC50m
2026-04-13 EIN122 - Apr 13, 03:05 UTCApr 13, 03:50 UTC45m
2026-04-12 EIN123 - Apr 12, 17:15 UTCApr 12, 19:00 UTC1h 45m

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

Mode-S 4CAAF1 frequently asked

What is Mode-S code 4CAAF1?
4CAAF1 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-EIK.
Where is Mode-S 4CAAF1 registered?
Mode-S code 4CAAF1 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAAF1 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAAF1, octal 23125361, decimal 5,024,497.
What flights does 4CAAF1 operate?
Mode-S 4CAAF1 has broadcast 4 distinct callsigns, including EIN1EN, EIN1MN, EIN123, EIN122.