sensors Mode-S transponder

4CAFB3

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-GSG · BOEING 737-800

Hex
4CAFB3
Octal
23127663
Decimal
5,025,715
Country
IE
Tail
EI-GSG
Type
B738
Photo of EI-GSG
No current signal · last broadcast 13h ago
Flights observed
16
Distinct callsigns
13
Country
IE
Last broadcast
13h ago

Last known position

Most recent position reported by Mode-S 4CAFB3.

Country allocation

The ICAO 24-bit address 4CAFB3 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 13 distinct

Callsign Airline Flights Last seen
RYR67VZ - 2 2026-04-14
RYR5WN - 2 2026-04-13
RYR5GT - 2 2026-04-13
RYR9389 - 1 2026-04-13
RYR8ZZ - 1 2026-04-12
RYR8TT Ryanair 1 2026-04-13
RYR6MQ - 1 2026-04-13
RYR5899 - 1 2026-04-14
RYR5526 - 1 2026-04-13
RYR54TQ - 1 2026-04-13
RYR41LZ - 1 2026-04-12
RYR401W - 1 2026-04-14
RYR2TR - 1 2026-04-13

Recent flights last 16

DateFlightRouteTakeoffLandingDuration
2026-04-14 RYR5899 - Apr 14, 09:10 UTCApr 14, 09:40 UTC30m
2026-04-14 RYR67VZ - Apr 14, 07:10 UTCApr 14, 08:30 UTC1h 20m
2026-04-14 RYR67VZ - Apr 14, 06:50 UTCApr 14, 07:10 UTC20m
2026-04-14 RYR401W - Apr 14, 05:15 UTCApr 14, 06:00 UTC45m
2026-04-13 RYR9389 - Apr 13, 22:20 UTCApr 13, 23:15 UTC55m
2026-04-13 RYR5GT - Apr 13, 19:50 UTCApr 13, 21:25 UTC1h 35m
2026-04-13 RYR5GT - Apr 13, 19:35 UTCApr 13, 20:10 UTC35m
2026-04-13 RYR2TR - Apr 13, 16:50 UTCApr 13, 18:25 UTC1h 35m
2026-04-13 RYR5526 - Apr 13, 15:05 UTCApr 13, 15:55 UTC50m
2026-04-13 RYR5WN - Apr 13, 12:20 UTCApr 13, 14:00 UTC1h 40m
2026-04-13 RYR5WN - Apr 13, 11:45 UTCApr 13, 12:15 UTC30m
2026-04-13 RYR6MQ - Apr 13, 08:25 UTCApr 13, 10:35 UTC2h 10m
2026-04-13 RYR54TQ - Apr 13, 06:20 UTCApr 13, 07:30 UTC1h 10m
2026-04-13 RYR8TT BVA → KRK Apr 13, 04:20 UTCApr 13, 05:20 UTC1h 0m
2026-04-12 RYR41LZ - Apr 12, 18:20 UTCApr 12, 19:20 UTC1h 0m
2026-04-12 RYR8ZZ - Apr 12, 17:15 UTCApr 12, 17:25 UTC10m

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

Mode-S 4CAFB3 frequently asked

What is Mode-S code 4CAFB3?
4CAFB3 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-GSG.
Where is Mode-S 4CAFB3 registered?
Mode-S code 4CAFB3 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAFB3 broadcasting right now?
No active broadcast right now. Last signal was 13h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAFB3, octal 23127663, decimal 5,025,715.
What flights does 4CAFB3 operate?
Mode-S 4CAFB3 has broadcast 13 distinct callsigns, including RYR67VZ, RYR5WN, RYR5GT, RYR9389, RYR8ZZ.