sensors Mode-S transponder

4CA961

ICAO 24-bit transponder address · allocated to Ireland

Currently assigned to EI-RZC · BOEING 737 MAX 8

Hex
4CA961
Octal
23124541
Decimal
5,024,097
Country
IE
Tail
EI-RZC
Type
B38M
No current signal · last broadcast 3h ago
Flights observed
198
Distinct callsigns
20
Country
IE
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 4CA961.

Country allocation

The ICAO 24-bit address 4CA961 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
NOS1446 - 12 2026-06-29
NOS1350 Neos 11 2026-05-11
NOS3004 - 9 2026-07-01
NOS2542 - 8 2026-06-30
NOS4357 Neos 7 2026-04-30
NOS6876 - 6 2026-07-04
NOS66QQ - 6 2026-07-04
NOS96AR - 5 2026-06-28
NOS6589 - 5 2026-06-27
NOS7179 Neos 4 2026-06-28
NOS7005 Neos 4 2026-06-28
NOS6347 - 4 2026-07-04
NOS60EK Neos 4 2026-06-29
NOS5893 Neos 4 2026-07-03
NOS5002 - 4 2026-07-03
NOS42YV Neos 4 2026-07-03
NOS41AK - 4 2026-07-04
NOS26PY - 4 2026-06-28
NOS14NA - 4 2026-07-03
NOS13BG Neos 4 2026-06-29

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 NOS36PC - Jul 13, 21:40 UTCJul 13, 23:05 UTC1h 25m
2026-07-13 NOS83YG MIR → DJE Jul 13, 20:15 UTCJul 13, 20:40 UTC25m
2026-07-13 NOS43MM FCO → MIR Jul 13, 18:20 UTCJul 13, 19:25 UTC1h 5m
2026-07-13 NOS1294 - Jul 13, 06:10 UTCJul 13, 16:20 UTC10h 10m
2026-07-12 NOS7644 - Jul 12, 16:20 UTCJul 12, 18:15 UTC1h 55m
2026-07-12 NOS7644 - Jul 12, 09:05 UTCJul 12, 15:45 UTC6h 40m
2026-07-11 NOS47SP - Jul 11, 20:20 UTCJul 11, 23:20 UTC3h 0m
2026-07-11 NOS35EW - Jul 11, 15:25 UTCJul 11, 18:40 UTC3h 15m
2026-07-11 NOS48EM - Jul 11, 11:45 UTCJul 11, 13:50 UTC2h 5m
2026-07-11 NOS6064 - Jul 11, 08:10 UTCJul 11, 10:05 UTC1h 55m
2026-07-10 NOS5500 - Jul 10, 16:10 UTCJul 11, 02:00 UTC9h 50m
2026-07-10 NOS51RP KGS → VRN Jul 10, 12:15 UTCJul 10, 14:25 UTC2h 10m
2026-07-10 NOS5032 - Jul 10, 08:45 UTCJul 10, 10:55 UTC2h 10m
2026-07-09 NOS4579 MAH → VRN Jul 9, 18:45 UTCJul 9, 19:55 UTC1h 10m
2026-07-09 NOS10VN VRN → MAH Jul 9, 16:30 UTCJul 9, 17:40 UTC1h 10m
2026-07-09 NOS4743 - Jul 9, 13:00 UTCJul 9, 14:15 UTC1h 15m
2026-07-09 NOS36RT - Jul 9, 10:10 UTCJul 9, 11:30 UTC1h 20m
2026-07-08 NOS3175 RHO → VRN Jul 8, 20:55 UTCJul 8, 23:25 UTC2h 30m
2026-07-08 NOS38PP - Jul 8, 17:30 UTCJul 8, 19:45 UTC2h 15m
2026-07-08 NOS3486 HER → VRN Jul 8, 14:10 UTCJul 8, 16:20 UTC2h 10m
2026-07-08 NOS23PE VRN → HER Jul 8, 10:25 UTCJul 8, 12:20 UTC1h 55m
2026-07-07 NOS2671 - Jul 7, 16:45 UTCJul 7, 23:00 UTC6h 15m
2026-07-07 NOS2246 VRN → MUH Jul 7, 14:35 UTCJul 7, 15:20 UTC45m
2026-07-07 NOS46JM - Jul 7, 06:45 UTCJul 7, 13:35 UTC6h 50m
2026-07-06 NOS62NW NBE → VRN Jul 6, 20:15 UTCJul 6, 21:45 UTC1h 30m
2026-07-06 NOS80RF DJE → NBE Jul 6, 18:30 UTCJul 6, 19:00 UTC30m
2026-07-06 NOS12JB VRN → DJE Jul 6, 15:45 UTCJul 6, 17:20 UTC1h 35m
2026-07-06 NOS1765 - Jul 6, 10:30 UTCJul 6, 14:05 UTC3h 35m
2026-07-06 NOS69SQ - Jul 6, 05:15 UTCJul 6, 08:50 UTC3h 35m
2026-07-05 NOS7929 - Jul 5, 16:45 UTCJul 6, 00:20 UTC7h 35m
2026-07-05 NOS7321 - Jul 5, 15:10 UTCJul 5, 15:30 UTC20m
2026-07-05 NOS80AM - Jul 5, 05:45 UTCJul 5, 13:35 UTC7h 50m
2026-07-04 NOS6023 - Jul 4, 23:05 UTCJul 5, 01:35 UTC2h 30m
2026-07-04 NOS33GL - Jul 4, 16:50 UTCJul 4, 19:45 UTC2h 55m
2026-07-04 NOS6347 - Jul 4, 13:55 UTCJul 4, 14:35 UTC40m
2026-07-04 NOS41AK - Jul 4, 11:30 UTCJul 4, 12:20 UTC50m
2026-07-04 NOS66QQ - Jul 4, 08:20 UTCJul 4, 09:35 UTC1h 15m
2026-07-04 NOS6876 - Jul 4, 05:45 UTCJul 4, 06:55 UTC1h 10m
2026-07-03 NOS5002 - Jul 3, 17:40 UTCJul 3, 19:55 UTC2h 15m
2026-07-03 NOS42YV MXP → AOK Jul 3, 14:15 UTCJul 3, 16:25 UTC2h 10m
2026-07-03 NOS5893 AOK → MXP Jul 3, 10:15 UTCJul 3, 12:40 UTC2h 25m
2026-07-03 NOS14NA - Jul 3, 06:15 UTCJul 3, 08:15 UTC2h 0m
2026-07-01 NOS3004 RHO → BLQ Jul 1, 12:25 UTCJul 1, 14:45 UTC2h 20m
2026-07-01 NOS3004 - Jul 1, 11:05 UTCJul 1, 11:30 UTC25m
2026-07-01 NOS3004 - Jul 1, 07:45 UTCJul 1, 09:35 UTC1h 50m
2026-06-30 NOS2542 - Jun 30, 06:15 UTCJun 30, 16:05 UTC9h 50m
2026-06-29 NOS1446 - Jun 29, 20:24 UTCJun 30, 00:14 UTC3h 50m
2026-06-29 NOS1446 - Jun 29, 13:24 UTCJun 29, 17:10 UTC3h 45m
2026-06-29 NOS13BG DJE → BLQ Jun 29, 09:05 UTCJun 29, 10:44 UTC1h 40m
2026-06-29 NOS60EK BLQ → MIR Jun 29, 05:09 UTCJun 29, 06:24 UTC1h 15m

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

Mode-S 4CA961 frequently asked

What is Mode-S code 4CA961?
4CA961 is an ICAO 24-bit transponder address. Allocated to Ireland. Assigned to EI-RZC.
Where is Mode-S 4CA961 registered?
Mode-S code 4CA961 is allocated to Ireland (IE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4CA961 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 4CA961, octal 23124541, decimal 5,024,097.
What flights does 4CA961 operate?
Mode-S 4CA961 has broadcast 20 distinct callsigns, including NOS1446, NOS1350, NOS3004, NOS2542, NOS4357.