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 Jul 26, 22:15 UTC
Flights observed
458
Distinct callsigns
20
Country
IE
Last broadcast
Jul 26, 22:15 UTC

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
2026-07-26 RYR2BU FNI → CRL Jul 26, 21:40 UTCJul 26, 22:15 UTC35m
2026-07-26 RYR44BA MRS → BLQ Jul 26, 19:50 UTCJul 26, 20:40 UTC50m
2026-07-26 RYR89YY BGY → SCQ Jul 26, 17:50 UTCJul 26, 18:55 UTC1h 5m
2026-07-26 RYR6774 - Jul 26, 15:55 UTCJul 26, 17:00 UTC1h 5m
2026-07-26 RYR4YZ EIN → SOF Jul 26, 14:05 UTCJul 26, 14:50 UTC45m
2026-07-26 RYR88YJ MRS → BGY Jul 26, 12:05 UTCJul 26, 12:50 UTC45m
2026-07-26 RYR49CB AGA → MRS Jul 26, 08:25 UTCJul 26, 10:40 UTC2h 15m
2026-07-26 RYR13MF MRS → AGA Jul 26, 04:35 UTCJul 26, 06:55 UTC2h 21m
2026-07-25 RYR8NK LUX → MRS Jul 25, 20:25 UTCJul 25, 21:35 UTC1h 10m
2026-07-25 RYR5SX MRS → LUX Jul 25, 18:25 UTCJul 25, 19:30 UTC1h 5m
2026-07-25 RYR45ZA - Jul 25, 16:15 UTCJul 25, 17:35 UTC1h 20m
2026-07-25 RYR249H MRS → LIL Jul 25, 14:20 UTCJul 25, 15:30 UTC1h 10m
2026-07-25 RYR46VF - Jul 25, 12:25 UTCJul 25, 13:30 UTC1h 5m
2026-07-25 RYR9CE VCE → PMO Jul 25, 10:40 UTCJul 25, 11:40 UTC1h 0m
2026-07-25 RYR92SE - Jul 25, 07:05 UTCJul 25, 09:00 UTC1h 55m
2026-07-25 RYR9MG TFS → MAN Jul 25, 04:35 UTCJul 25, 06:20 UTC1h 45m
2026-07-24 RYR58SW - Jul 24, 15:40 UTCJul 24, 21:05 UTC5h 25m
2026-07-24 RYR96UL - Jul 24, 13:30 UTCJul 24, 14:35 UTC1h 5m
2026-07-24 RYR84QP - Jul 24, 11:30 UTCJul 24, 12:35 UTC1h 5m
2026-07-24 RYR2UK TTU → AGP Jul 24, 08:20 UTCJul 24, 10:35 UTC2h 15m
2026-07-24 RYR7CY DUB → ZAD Jul 24, 04:40 UTCJul 24, 06:50 UTC2h 10m
2026-07-23 RYR185L DUB → MRS Jul 23, 19:30 UTCJul 23, 21:25 UTC1h 55m
2026-07-23 RYR88VB STN → DUB Jul 23, 17:30 UTCJul 23, 18:30 UTC1h 0m
2026-07-23 RYR73SF - Jul 23, 15:35 UTCJul 23, 16:30 UTC55m
2026-07-23 RYR7128 DUB → FUE Jul 23, 05:05 UTCJul 23, 13:30 UTC8h 25m
2026-07-22 RYR93SC PEG → STN Jul 22, 21:05 UTCJul 22, 22:00 UTC55m
2026-07-22 RYR70SV DUB → LGW Jul 22, 18:50 UTCJul 22, 19:40 UTC50m
2026-07-22 RYR9LY - Jul 22, 15:40 UTCJul 22, 18:00 UTC2h 20m
2026-07-22 RYR43DT DUB → NCE Jul 22, 12:30 UTCJul 22, 14:30 UTC2h 0m
2026-07-22 RYR69XF DUB → FAO Jul 22, 04:55 UTCJul 22, 10:25 UTC5h 30m
2026-07-21 RYR2MN KRK → RHO Jul 21, 21:40 UTCJul 21, 23:40 UTC2h 0m
2026-07-21 RYR81YQ - Jul 21, 18:20 UTCJul 21, 20:25 UTC2h 5m
2026-07-21 RYR6FH - Jul 21, 17:00 UTCJul 21, 17:30 UTC30m
2026-07-21 RYR69KF - Jul 21, 15:55 UTCJul 21, 16:25 UTC30m
2026-07-21 RYR33PC BRS → DUB Jul 21, 14:15 UTCJul 21, 14:55 UTC40m
2026-07-21 RYR565K DUB → BRS Jul 21, 12:35 UTCJul 21, 13:20 UTC45m
2026-07-21 RYR31MX REU → DUB Jul 21, 09:25 UTCJul 21, 11:35 UTC2h 10m
2026-07-21 RYR59PZ - Jul 21, 06:20 UTCJul 21, 08:20 UTC2h 0m
2026-07-20 RYR1715 CFU → DUB Jul 20, 16:45 UTCJul 20, 20:10 UTC3h 25m
2026-07-20 RYR94VW - Jul 20, 12:00 UTCJul 20, 15:00 UTC3h 0m
2026-07-20 RYR720F LPL → DUB Jul 20, 10:10 UTCJul 20, 10:40 UTC30m
2026-07-20 RYR2SM - Jul 20, 08:30 UTCJul 20, 09:05 UTC35m
2026-07-20 RYR19FC EDI → DUB Jul 20, 06:55 UTCJul 20, 07:30 UTC35m
2026-07-20 RYR66LN DUB → EDI Jul 20, 05:25 UTCJul 20, 06:10 UTC45m
2026-07-19 RYR7SF - Jul 19, 18:25 UTCJul 19, 22:40 UTC4h 15m
2026-07-19 RYR65HX - Jul 19, 13:25 UTCJul 19, 17:15 UTC3h 50m
2026-07-19 RYR017 NCL → DUB Jul 19, 11:05 UTCJul 19, 11:45 UTC40m
2026-07-19 RYR9BL DUB → NCL Jul 19, 09:40 UTCJul 19, 10:25 UTC45m
2026-07-19 RYR1FT - Jul 19, 08:05 UTCJul 19, 08:50 UTC45m
2026-07-19 RYR146G - Jul 19, 06:00 UTCJul 19, 06:35 UTC35m

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 Jul 26, 22:15 UTC.
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.