sensors Mode-S transponder

4CA1CE

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-HUU · EMBRAER ERJ-190-400

Hex
4CA1CE
Octal
23120716
Decimal
5,022,158
Country
IE
Tail
EI-HUU
Type
E295
No current signal
Flights observed
0
Distinct callsigns
11
Country
IE
Last broadcast
-

Country allocation

The ICAO 24-bit address 4CA1CE 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 11 distinct

Callsign Airline Flights Last seen
MML801 - 28 2026-07-16
MML802 - 24 2026-07-16
MML12 - 9 2026-06-27
MML11 - 9 2026-06-26
MML812 - 5 2026-07-14
MML818 - 3 2026-07-04
MML2 - 3 2026-04-21
MML892 - 2 2026-07-17
MML674 Hunnu Air 2 2026-05-06
MML673 Hunnu Air 2 2026-05-06
MML817 - 1 2026-06-20

Recent flights

No flights recorded yet for this transponder.

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

Mode-S 4CA1CE frequently asked

What is Mode-S code 4CA1CE?
4CA1CE is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-HUU.
Where is Mode-S 4CA1CE registered?
Mode-S code 4CA1CE is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CA1CE broadcasting right now?
No active broadcast right now.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CA1CE, octal 23120716, decimal 5,022,158.
What flights does 4CA1CE operate?
Mode-S 4CA1CE has broadcast 11 distinct callsigns, including MML801, MML802, MML12, MML11, MML812.