sensors Mode-S transponder

4CAF27

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-ILM · BOEING 737 MAX 8

Hex
4CAF27
Octal
23127447
Decimal
5,025,575
Country
IE
Tail
EI-ILM
Type
B38M
Broadcasting now · callsign RYR5084 · 27,425 ft
Flights observed
17
Distinct callsigns
7
Country
IE
Last broadcast
17h ago

Current position

4CAF27 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 4CAF27 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 7 distinct

Callsign Airline Flights Last seen
RYR9GF Ryanair 4 2026-04-14
RYR29SG - 4 2026-04-13
RYR44KF - 3 2026-04-13
RYR86EP - 2 2026-04-13
RYR49TQ - 2 2026-04-14
RYR9JG - 1 2026-04-14
RYR5881 - 1 2026-04-12

Recent flights last 17

DateFlightRouteTakeoffLandingDuration
2026-04-14 RYR9GF IBZ → VLC Apr 14, 10:30 UTCApr 14, 11:05 UTC35m
2026-04-14 RYR49TQ - Apr 14, 07:10 UTCApr 14, 09:05 UTC1h 55m
2026-04-14 RYR49TQ - Apr 14, 06:30 UTCApr 14, 07:10 UTC40m
2026-04-14 RYR9JG - Apr 14, 05:15 UTCApr 14, 05:40 UTC25m
2026-04-13 RYR86EP - Apr 13, 19:50 UTCApr 13, 21:45 UTC1h 55m
2026-04-13 RYR86EP - Apr 13, 17:50 UTCApr 13, 20:10 UTC2h 20m
2026-04-13 RYR29SG - Apr 13, 16:15 UTCApr 13, 16:30 UTC15m
2026-04-13 RYR29SG - Apr 13, 15:50 UTCApr 13, 16:30 UTC40m
2026-04-13 RYR29SG - Apr 13, 12:20 UTCApr 13, 16:15 UTC3h 55m
2026-04-13 RYR29SG - Apr 13, 12:05 UTCApr 13, 12:15 UTC10m
2026-04-13 RYR44KF - Apr 13, 08:20 UTCApr 13, 10:15 UTC1h 55m
2026-04-13 RYR44KF - Apr 13, 07:55 UTCApr 13, 10:15 UTC2h 20m
2026-04-13 RYR44KF - Apr 13, 07:20 UTCApr 13, 08:15 UTC55m
2026-04-13 RYR9GF IBZ → VLC Apr 13, 04:20 UTCApr 13, 06:35 UTC2h 15m
2026-04-13 RYR9GF IBZ → VLC Apr 13, 04:00 UTCApr 13, 06:35 UTC2h 35m
2026-04-13 RYR9GF IBZ → VLC Apr 13, 02:55 UTCApr 13, 04:15 UTC1h 20m
2026-04-12 RYR5881 - Apr 12, 17:25 UTCApr 12, 20:00 UTC2h 35m

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

Mode-S 4CAF27 frequently asked

What is Mode-S code 4CAF27?
4CAF27 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-ILM.
Where is Mode-S 4CAF27 registered?
Mode-S code 4CAF27 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAF27 broadcasting right now?
Yes. Mode-S 4CAF27 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAF27, octal 23127447, decimal 5,025,575.
What flights does 4CAF27 operate?
Mode-S 4CAF27 has broadcast 7 distinct callsigns, including RYR9GF, RYR29SG, RYR44KF, RYR86EP, RYR49TQ.