sensors Mode-S transponder

4CAFC1

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-GSJ · BOEING 737-800

Hex
4CAFC1
Octal
23127701
Decimal
5,025,729
Country
IE
Tail
EI-GSJ
Type
B738
No current signal · last broadcast 11h ago
Flights observed
384
Distinct callsigns
20
Country
IE
Last broadcast
11h ago

Last known position

Most recent position reported by Mode-S 4CAFC1.

Country allocation

The ICAO 24-bit address 4CAFC1 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 20 distinct

Callsign Airline Flights Last seen
RYR9PK - 3 2026-07-07
RYR7WV - 3 2026-06-24
RYR7209 - 3 2026-06-26
RYR71LM - 3 2026-06-24
RYR6RX Ryanair 3 2026-06-05
RYR6HR - 3 2026-06-26
RYR6923 Ryanair 3 2026-07-06
RYR6922 Ryanair 3 2026-07-06
RYR615 - 3 2026-06-23
RYR5GG Ryanair 3 2026-05-25
RYR578E - 3 2026-07-04
RYR56EF Ryanair 3 2026-06-05
RYR5275 Ryanair 3 2026-06-26
RYR51XX - 3 2026-06-26
RYR3VU - 3 2026-06-24
RYR3PW - 3 2026-07-04
RYR34DV Ryanair 3 2026-05-25
RYR32ST - 3 2026-06-25
RYR326 - 3 2026-07-06
RYR325 - 3 2026-07-06

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 RYR7BE BCN → BGY Jul 13, 20:50 UTCJul 13, 22:10 UTC1h 20m
2026-07-13 RYR1QN - Jul 13, 18:30 UTCJul 13, 19:45 UTC1h 15m
2026-07-13 RYR866B - Jul 13, 16:15 UTCJul 13, 17:20 UTC1h 5m
2026-07-13 RYR10XW - Jul 13, 13:15 UTCJul 13, 14:55 UTC1h 40m
2026-07-13 RYR425M - Jul 13, 10:30 UTCJul 13, 12:20 UTC1h 50m
2026-07-13 RYR19VQ - Jul 13, 08:25 UTCJul 13, 09:40 UTC1h 15m
2026-07-12 RYR8979 - Jul 12, 18:40 UTCJul 12, 20:01 UTC1h 20m
2026-07-12 RYR66WD - Jul 12, 16:10 UTCJul 12, 17:45 UTC1h 35m
2026-07-12 RYR88WF - Jul 12, 13:35 UTCJul 12, 15:20 UTC1h 45m
2026-07-12 RYR8YE - Jul 12, 11:25 UTCJul 12, 12:15 UTC50m
2026-07-12 RYR71SR - Jul 12, 09:40 UTCJul 12, 10:30 UTC50m
2026-07-12 RYR1YY - Jul 12, 06:55 UTCJul 12, 08:50 UTC1h 55m
2026-07-12 RYR322K - Jul 12, 04:05 UTCJul 12, 06:05 UTC2h 0m
2026-07-11 RYR688B - Jul 11, 19:55 UTCJul 11, 21:00 UTC1h 5m
2026-07-11 RYR86LD - Jul 11, 17:55 UTCJul 11, 19:05 UTC1h 10m
2026-07-11 RYR3254 BCN → XRY Jul 11, 14:50 UTCJul 11, 17:05 UTC2h 15m
2026-07-11 RYR3255 - Jul 11, 11:50 UTCJul 11, 14:00 UTC2h 10m
2026-07-11 RYR6503 - Jul 11, 07:30 UTCJul 11, 09:50 UTC2h 20m
2026-07-11 RYR6504 - Jul 11, 04:01 UTCJul 11, 06:35 UTC2h 35m
2026-07-10 RYR5665 - Jul 10, 19:40 UTCJul 10, 21:30 UTC1h 50m
2026-07-10 RYR1XD - Jul 10, 17:00 UTCJul 10, 18:55 UTC1h 55m
2026-07-10 RYR4KF - Jul 10, 14:45 UTCJul 10, 15:55 UTC1h 10m
2026-07-10 RYR8XX DUB → STN Jul 10, 12:35 UTCJul 10, 13:45 UTC1h 10m
2026-07-10 RYR24RD - Jul 10, 10:10 UTCJul 10, 11:10 UTC1h 0m
2026-07-10 RYR636E - Jul 10, 08:05 UTCJul 10, 09:10 UTC1h 5m
2026-07-10 RYR23ML - Jul 10, 05:55 UTCJul 10, 07:10 UTC1h 15m
2026-07-10 RYR82XC - Jul 10, 03:45 UTCJul 10, 05:05 UTC1h 20m
2026-07-09 RYR58BW - Jul 9, 20:30 UTCJul 9, 21:40 UTC1h 10m
2026-07-09 RYR451P - Jul 9, 17:45 UTCJul 9, 19:20 UTC1h 35m
2026-07-09 RYR394R - Jul 9, 15:25 UTCJul 9, 16:55 UTC1h 30m
2026-07-09 RYR96EU - Jul 9, 13:10 UTCJul 9, 14:25 UTC1h 15m
2026-07-09 RYR97WV - Jul 9, 11:00 UTCJul 9, 12:25 UTC1h 25m
2026-07-09 RYR3YU - Jul 9, 08:10 UTCJul 9, 10:10 UTC2h 0m
2026-07-09 RYR2WZ - Jul 9, 05:35 UTCJul 9, 07:15 UTC1h 40m
2026-07-08 RYR465X - Jul 8, 21:20 UTCJul 8, 22:45 UTC1h 25m
2026-07-08 RYR65HL - Jul 8, 19:10 UTCJul 8, 20:20 UTC1h 10m
2026-07-08 RYR873M - Jul 8, 17:15 UTCJul 8, 18:15 UTC1h 0m
2026-07-08 RYR2976 - Jul 8, 14:45 UTCJul 8, 16:00 UTC1h 15m
2026-07-08 RYR2975 - Jul 8, 12:50 UTCJul 8, 14:10 UTC1h 20m
2026-07-08 RYR22RD - Jul 8, 09:40 UTCJul 8, 11:55 UTC2h 15m
2026-07-08 RYR3RB - Jul 8, 06:00 UTCJul 8, 08:20 UTC2h 20m
2026-07-07 RYR8FY - Jul 7, 15:15 UTCJul 7, 18:20 UTC3h 5m
2026-07-07 RYR7986 - Jul 7, 11:20 UTCJul 7, 14:05 UTC2h 45m
2026-07-07 RYR9PK - Jul 7, 07:15 UTCJul 7, 10:20 UTC3h 5m
2026-07-07 RYR2BD - Jul 7, 05:50 UTCJul 7, 06:20 UTC30m
2026-07-07 RYR11EX - Jul 7, 04:15 UTCJul 7, 04:40 UTC25m
2026-07-06 RYR326 - Jul 6, 20:40 UTCJul 6, 21:55 UTC1h 15m
2026-07-06 RYR325 - Jul 6, 18:35 UTCJul 6, 19:40 UTC1h 5m
2026-07-06 RYR6923 JTR → ATH Jul 6, 17:20 UTCJul 6, 17:45 UTC25m
2026-07-06 RYR6922 ATH → JTR Jul 6, 16:00 UTCJul 6, 16:25 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-GSJ page for operator, model, and routing details .

Mode-S 4CAFC1 frequently asked

What is Mode-S code 4CAFC1?
4CAFC1 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-GSJ.
Where is Mode-S 4CAFC1 registered?
Mode-S code 4CAFC1 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAFC1 broadcasting right now?
No active broadcast right now. Last signal was 11h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAFC1, octal 23127701, decimal 5,025,729.
What flights does 4CAFC1 operate?
Mode-S 4CAFC1 has broadcast 20 distinct callsigns, including RYR9PK, RYR7WV, RYR7209, RYR71LM, RYR6RX.