sensors Mode-S transponder

4CAC23

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-HGL · BOEING 737 MAX 8

Hex
4CAC23
Octal
23126043
Decimal
5,024,803
Country
IE
Tail
EI-HGL
Type
B38M
No current signal · last broadcast 3h ago
Flights observed
544
Distinct callsigns
20
Country
IE
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 4CAC23.

Country allocation

The ICAO 24-bit address 4CAC23 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
RYR9JT Ryanair 4 2026-05-15
RYR52SL Ryanair 4 2026-05-15
RYR9ET - 3 2026-07-14
RYR7EE - 3 2026-04-15
RYR7668 Ryanair 3 2026-05-16
RYR74WC - 3 2026-06-18
RYR6TX - 3 2026-07-13
RYR55HB - 3 2026-07-14
RYR50UT Ryanair 3 2026-05-06
RYR506G - 3 2026-04-13
RYR439L Ryanair 3 2026-05-24
RYR314U Ryanair 3 2026-05-16
RYR22LN - 3 2026-04-15
RYR20FV - 3 2026-04-13
RYR1YJ Ryanair 3 2026-05-06
RYR1UB Ryanair 3 2026-05-16
RYR9YF Ryanair 2 2026-05-02
RYR9TM - 2 2026-06-24
RYR99RH Ryanair 2 2026-04-14
RYR98ST Ryanair 2 2026-05-13

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 RYR2167 RZE → STN Jul 14, 21:40 UTCJul 15, 00:05 UTC2h 24m
2026-07-14 RYR2166 STN → RZE Jul 14, 18:50 UTCJul 14, 20:50 UTC2h 0m
2026-07-14 RYR9ET PEG → STN Jul 14, 15:25 UTCJul 14, 17:35 UTC2h 10m
2026-07-14 RYR55HB STN → PEG Jul 14, 11:35 UTCJul 14, 13:35 UTC2h 0m
2026-07-14 RYR1PX - Jul 14, 09:10 UTCJul 14, 10:35 UTC1h 25m
2026-07-14 RYR67UB - Jul 14, 06:40 UTCJul 14, 07:50 UTC1h 10m
2026-07-13 RYR14VV - Jul 13, 23:20 UTCJul 14, 01:05 UTC1h 45m
2026-07-13 RYR65XA - Jul 13, 20:50 UTCJul 13, 22:20 UTC1h 30m
2026-07-13 RYR6TX - Jul 13, 17:55 UTCJul 13, 19:50 UTC1h 55m
2026-07-13 RYR297X - Jul 13, 11:30 UTCJul 13, 12:50 UTC1h 20m
2026-07-13 RYR1EA - Jul 13, 08:35 UTCJul 13, 10:40 UTC2h 5m
2026-07-13 RYR62RA - Jul 13, 05:15 UTCJul 13, 07:45 UTC2h 30m
2026-07-12 RYR3496 - Jul 12, 22:15 UTCJul 12, 23:15 UTC1h 0m
2026-07-12 RYR3497 - Jul 12, 20:05 UTCJul 12, 21:20 UTC1h 15m
2026-07-12 RYR99JH - Jul 12, 18:05 UTCJul 12, 19:10 UTC1h 5m
2026-07-12 RYR15FX - Jul 12, 15:35 UTCJul 12, 16:55 UTC1h 20m
2026-07-12 RYR5604 CIA → TLL Jul 12, 12:35 UTCJul 12, 14:20 UTC1h 45m
2026-07-12 RYR5605 TLL → CIA Jul 12, 09:40 UTCJul 12, 11:45 UTC2h 5m
2026-07-12 RYR769T - Jul 12, 07:10 UTCJul 12, 08:30 UTC1h 20m
2026-07-12 RYR69TU - Jul 12, 04:50 UTCJul 12, 06:15 UTC1h 25m
2026-07-11 RYR7091 - Jul 11, 22:10 UTCJul 11, 22:45 UTC35m
2026-07-11 RYR11LM - Jul 11, 20:30 UTCJul 11, 21:00 UTC30m
2026-07-11 RYR9969 - Jul 11, 17:35 UTCJul 11, 19:30 UTC1h 55m
2026-07-11 RYR5MP - Jul 11, 14:45 UTCJul 11, 16:40 UTC1h 55m
2026-07-11 RYR5XD - Jul 11, 11:45 UTCJul 11, 13:30 UTC1h 45m
2026-07-11 RYR43HC - Jul 11, 09:15 UTCJul 11, 10:55 UTC1h 40m
2026-07-11 RYR38JR - Jul 11, 05:35 UTCJul 11, 07:10 UTC1h 35m
2026-07-10 RYR5951 - Jul 10, 20:10 UTCJul 10, 22:15 UTC2h 5m
2026-07-10 RYR449K - Jul 10, 16:35 UTCJul 10, 18:55 UTC2h 20m
2026-07-10 RYR82JL HAM → STN Jul 10, 13:50 UTCJul 10, 14:55 UTC1h 5m
2026-07-10 RYR45TM - Jul 10, 11:45 UTCJul 10, 12:45 UTC1h 0m
2026-07-10 RYR8DU ARN → STN Jul 10, 08:50 UTCJul 10, 10:55 UTC2h 5m
2026-07-10 RYR305X STN → ARN Jul 10, 05:40 UTCJul 10, 07:35 UTC1h 55m
2026-07-09 RYR16DM - Jul 9, 20:05 UTCJul 9, 21:20 UTC1h 15m
2026-07-09 RYR69BF - Jul 9, 17:00 UTCJul 9, 18:40 UTC1h 40m
2026-07-09 RYR19JN - Jul 9, 14:30 UTCJul 9, 15:55 UTC1h 25m
2026-07-09 RYR30ZG - Jul 9, 12:00 UTCJul 9, 13:25 UTC1h 25m
2026-07-09 RYR1BL - Jul 9, 09:25 UTCJul 9, 11:00 UTC1h 35m
2026-07-09 RYR87SW - Jul 9, 06:35 UTCJul 9, 08:10 UTC1h 35m
2026-07-08 RYR8MK TLL → STN Jul 8, 19:15 UTCJul 8, 21:50 UTC2h 35m
2026-07-08 RYR3SM - Jul 8, 15:55 UTCJul 8, 18:15 UTC2h 20m
2026-07-08 RYR6TX - Jul 8, 12:45 UTCJul 8, 14:35 UTC1h 50m
2026-07-08 RYR35MN - Jul 8, 10:20 UTCJul 8, 11:50 UTC1h 30m
2026-07-08 RYR7CQ PRG → STN Jul 8, 07:40 UTCJul 8, 09:20 UTC1h 40m
2026-07-08 RYR11GQ - Jul 8, 05:20 UTCJul 8, 06:45 UTC1h 25m
2026-07-07 RYR63UE BDS → STN Jul 7, 20:10 UTCJul 7, 22:50 UTC2h 40m
2026-07-07 RYR20RR - Jul 7, 17:00 UTCJul 7, 19:20 UTC2h 20m
2026-07-07 RYR50NV MXP → STN Jul 7, 14:35 UTCJul 7, 16:05 UTC1h 30m
2026-07-07 RYR19DM - Jul 7, 11:55 UTCJul 7, 13:20 UTC1h 25m
2026-07-07 RUK85XY OSL → STN Jul 7, 09:05 UTCJul 7, 10:40 UTC1h 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-HGL page for operator, model, and routing details .

Mode-S 4CAC23 frequently asked

What is Mode-S code 4CAC23?
4CAC23 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-HGL.
Where is Mode-S 4CAC23 registered?
Mode-S code 4CAC23 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CAC23 broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CAC23, octal 23126043, decimal 5,024,803.
What flights does 4CAC23 operate?
Mode-S 4CAC23 has broadcast 20 distinct callsigns, including RYR9JT, RYR52SL, RYR9ET, RYR7EE, RYR7668.