sensors Mode-S transponder

4CA854

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-EML · BOEING 737-800

Hex
4CA854
Octal
23124124
Decimal
5,023,828
Country
IE
Tail
EI-EML
Type
B738
Photo of EI-EML
No current signal · last broadcast 14h ago
Flights observed
15
Distinct callsigns
9
Country
IE
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S 4CA854.

Country allocation

The ICAO 24-bit address 4CA854 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 9 distinct

Callsign Airline Flights Last seen
RYR8KB - 3 2026-04-13
RYR7NQ - 3 2026-04-13
RYR6JJ - 2 2026-04-14
RYR3631 - 2 2026-04-13
RYR9B - 1 2026-04-12
RYR73LC - 1 2026-04-13
RYR4FP - 1 2026-04-14
RYR16EA - 1 2026-04-13
RYR1193 Ryanair 1 2026-04-13

Recent flights last 15

DateFlightRouteTakeoffLandingDuration
2026-04-14 RYR6JJ - Apr 14, 09:10 UTCApr 14, 10:30 UTC1h 20m
2026-04-14 RYR6JJ - Apr 14, 08:25 UTCApr 14, 09:05 UTC40m
2026-04-14 RYR4FP - Apr 14, 05:15 UTCApr 14, 06:55 UTC1h 40m
2026-04-13 RYR7NQ - Apr 13, 19:50 UTCApr 13, 20:40 UTC50m
2026-04-13 RYR7NQ - Apr 13, 16:15 UTCApr 13, 20:10 UTC3h 55m
2026-04-13 RYR7NQ - Apr 13, 15:50 UTCApr 13, 19:45 UTC3h 55m
2026-04-13 RYR73LC - Apr 13, 14:35 UTCApr 13, 16:15 UTC1h 40m
2026-04-13 RYR3631 - Apr 13, 12:20 UTCApr 13, 13:25 UTC1h 5m
2026-04-13 RYR3631 - Apr 13, 12:05 UTCApr 13, 12:15 UTC10m
2026-04-13 RYR16EA - Apr 13, 09:55 UTCApr 13, 11:15 UTC1h 20m
2026-04-13 RYR8KB - Apr 13, 08:20 UTCApr 13, 08:30 UTC10m
2026-04-13 RYR8KB - Apr 13, 07:55 UTCApr 13, 08:30 UTC35m
2026-04-13 RYR8KB - Apr 13, 07:00 UTCApr 13, 08:15 UTC1h 15m
2026-04-13 RYR1193 TLS → SVQ Apr 13, 04:30 UTCApr 13, 05:50 UTC1h 20m
2026-04-12 RYR9B - Apr 12, 17:15 UTCApr 12, 17:40 UTC25m

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

Mode-S 4CA854 frequently asked

What is Mode-S code 4CA854?
4CA854 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-EML.
Where is Mode-S 4CA854 registered?
Mode-S code 4CA854 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CA854 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 4CA854, octal 23124124, decimal 5,023,828.
What flights does 4CA854 operate?
Mode-S 4CA854 has broadcast 9 distinct callsigns, including RYR8KB, RYR7NQ, RYR6JJ, RYR3631, RYR9B.