sensors Mode-S transponder

4CA621

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-DWT · BOEING 737-800

Hex
4CA621
Octal
23123041
Decimal
5,023,265
Country
IE
Tail
EI-DWT
Type
B738
No current signal · last broadcast 12h ago
Flights observed
629
Distinct callsigns
20
Country
IE
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S 4CA621.

Country allocation

The ICAO 24-bit address 4CA621 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
RYR6RX Ryanair 6 2026-06-07
RYR56EF Ryanair 6 2026-06-07
RYR65QN Ryanair 5 2026-06-06
RYR1VB Ryanair 5 2026-06-06
RYR72PP Ryanair 4 2026-04-17
RYR68NX Ryanair 4 2026-06-04
RYR5SM Ryanair 4 2026-05-30
RYR4YF Ryanair 4 2026-05-30
RYR41LL Ryanair 4 2026-06-03
RYR28TV Ryanair 4 2026-04-17
RYR21GB Ryanair 4 2026-06-03
RYR9RN - 3 2026-04-13
RYR9K Ryanair 3 2026-06-05
RYR98XK Ryanair 3 2026-04-15
RYR98RQ Ryanair 3 2026-06-04
RYR945 Ryanair 3 2026-06-07
RYR88DL - 3 2026-04-13
RYR85JL Ryanair 3 2026-05-28
RYR83GT Ryanair 3 2026-05-10
RYR838P Ryanair 3 2026-04-15

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 RYR74FZ - Jul 13, 18:15 UTCJul 13, 20:20 UTC2h 5m
2026-07-13 RYR2M LTN → KUN Jul 13, 15:15 UTCJul 13, 17:35 UTC2h 20m
2026-07-13 RYR86DX DUB → LTN Jul 13, 13:30 UTCJul 13, 14:20 UTC50m
2026-07-13 RYR51YC - Jul 13, 11:35 UTCJul 13, 12:35 UTC1h 0m
2026-07-13 RYR74XH - Jul 13, 08:25 UTCJul 13, 10:40 UTC2h 15m
2026-07-13 RYR41NU - Jul 13, 05:31 UTCJul 13, 07:30 UTC2h 0m
2026-07-12 RYR29XJ - Jul 12, 20:30 UTCJul 12, 22:40 UTC2h 10m
2026-07-12 RYR9YC - Jul 12, 16:25 UTCJul 12, 19:05 UTC2h 40m
2026-07-12 RYR3MP - Jul 12, 12:30 UTCJul 12, 14:50 UTC2h 20m
2026-07-12 RYR7MN - Jul 12, 07:50 UTCJul 12, 11:05 UTC3h 15m
2026-07-12 RYR85QL - Jul 12, 04:05 UTCJul 12, 06:55 UTC2h 50m
2026-07-11 RYR3AD - Jul 11, 20:45 UTCJul 11, 21:40 UTC55m
2026-07-11 RYR27YZ - Jul 11, 19:20 UTCJul 11, 20:00 UTC40m
2026-07-11 RYR262A LTN → AGP Jul 11, 15:50 UTCJul 11, 18:20 UTC2h 30m
2026-07-11 RYR29XJ - Jul 11, 12:10 UTCJul 11, 14:25 UTC2h 15m
2026-07-11 RYR354L - Jul 11, 08:01 UTCJul 11, 10:45 UTC2h 45m
2026-07-11 RYR9929 - Jul 11, 04:20 UTCJul 11, 07:10 UTC2h 50m
2026-07-10 RYR6JC - Jul 10, 20:35 UTCJul 10, 22:55 UTC2h 20m
2026-07-10 RYR42WC - Jul 10, 17:00 UTCJul 10, 19:25 UTC2h 25m
2026-07-10 RYR827R - Jul 10, 13:30 UTCJul 10, 15:50 UTC2h 20m
2026-07-10 RYR7QD - Jul 10, 10:30 UTCJul 10, 12:30 UTC2h 0m
2026-07-10 RYR209L - Jul 10, 06:20 UTCJul 10, 09:20 UTC3h 0m
2026-07-09 RYR32FQ - Jul 9, 20:30 UTCJul 9, 23:25 UTC2h 55m
2026-07-09 RYR40KU - Jul 9, 16:20 UTCJul 9, 19:20 UTC3h 0m
2026-07-09 RYR1JN - Jul 9, 13:50 UTCJul 9, 15:10 UTC1h 20m
2026-07-09 RYR209J - Jul 9, 11:50 UTCJul 9, 12:55 UTC1h 5m
2026-07-09 RYR9RL - Jul 9, 08:35 UTCJul 9, 10:55 UTC2h 20m
2026-07-09 RYR618X - Jul 9, 05:20 UTCJul 9, 07:55 UTC2h 35m
2026-07-08 RYR776U - Jul 8, 21:25 UTCJul 8, 22:20 UTC55m
2026-07-08 RYR3ZF - Jul 8, 19:40 UTCJul 8, 20:35 UTC55m
2026-07-08 RYR556J - Jul 8, 14:30 UTCJul 8, 16:50 UTC2h 20m
2026-07-08 RYR42NF - Jul 8, 11:15 UTCJul 8, 13:40 UTC2h 25m
2026-07-08 RYR5UB - Jul 8, 07:00 UTCJul 8, 09:15 UTC2h 15m
2026-07-07 RYR6BY - Jul 7, 18:50 UTCJul 7, 20:10 UTC1h 20m
2026-07-07 RYR6QT - Jul 7, 17:00 UTCJul 7, 18:05 UTC1h 5m
2026-07-07 RYR2RG - Jul 7, 13:25 UTCJul 7, 15:50 UTC2h 25m
2026-07-07 RYR515T - Jul 7, 10:00 UTCJul 7, 12:15 UTC2h 15m
2026-07-07 RYR2122 PRG → CRL Jul 7, 08:00 UTCJul 7, 09:05 UTC1h 5m
2026-07-07 RYR5TE - Jul 7, 05:55 UTCJul 7, 07:00 UTC1h 5m
2026-07-06 RYR19HF - Jul 6, 18:55 UTCJul 6, 20:55 UTC2h 0m
2026-07-06 RYR86VH - Jul 6, 15:25 UTCJul 6, 17:20 UTC1h 55m
2026-07-06 RYR4MA - Jul 6, 12:40 UTCJul 6, 14:40 UTC2h 0m
2026-07-06 RYR140E - Jul 6, 09:50 UTCJul 6, 11:35 UTC1h 45m
2026-07-06 RYR7WU - Jul 6, 07:25 UTCJul 6, 08:45 UTC1h 20m
2026-07-06 RYR56DD - Jul 6, 05:30 UTCJul 6, 06:40 UTC1h 10m
2026-07-05 RYR1EQ - Jul 5, 21:15 UTCJul 5, 22:35 UTC1h 20m
2026-07-05 RYR2NC - Jul 5, 19:15 UTCJul 5, 20:30 UTC1h 15m
2026-07-05 RYR40HP FAO → CRL Jul 5, 15:45 UTCJul 5, 18:15 UTC2h 30m
2026-07-05 RYR25UT - Jul 5, 11:30 UTCJul 5, 13:50 UTC2h 20m
2026-07-05 RYR78GP FAO → BHX Jul 5, 07:50 UTCJul 5, 10:20 UTC2h 30m

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

Mode-S 4CA621 frequently asked

What is Mode-S code 4CA621?
4CA621 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-DWT.
Where is Mode-S 4CA621 registered?
Mode-S code 4CA621 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CA621 broadcasting right now?
No active broadcast right now. Last signal was 12h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4CA621, octal 23123041, decimal 5,023,265.
What flights does 4CA621 operate?
Mode-S 4CA621 has broadcast 20 distinct callsigns, including RYR6RX, RYR56EF, RYR65QN, RYR1VB, RYR72PP.