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sensors Mode-S transponder

C81C33

ICAO 24-bit transponder address · allocated to New Zealand

Currently assigned to ZK-NPK · CESSNA 152

Hex
C81C33
Octal
62016063
Decimal
13,114,419
Country
NZ
Tail
ZK-NPK
Type
C152
No current signal · last broadcast Jul 26, 22:45 UTC
Flights observed
262
Distinct callsigns
1
Country
NZ
Last broadcast
Jul 26, 22:45 UTC

Last known position

Most recent position reported by Mode-S C81C33.

Country allocation

The ICAO 24-bit address C81C33 falls within the block assigned to New Zealand (NZ) by ICAO Annex 10, Volume III. Every aircraft registered in New Zealand 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 1 distinct

Callsign Airline Flights Last seen
ZKNPK - 262 2026-07-26

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 ZKNPK - Jul 26, 22:10 UTCJul 26, 22:45 UTC35m
2026-07-24 ZKNPK - Jul 24, 03:10 UTCJul 24, 03:35 UTC25m
2026-07-24 ZKNPK - Jul 24, 00:55 UTCJul 24, 01:25 UTC30m
2026-07-23 ZKNPK - Jul 23, 23:20 UTCJul 24, 00:05 UTC45m
2026-07-23 ZKNPK - Jul 23, 21:20 UTCJul 23, 22:15 UTC55m
2026-07-23 ZKNPK - Jul 23, 05:45 UTCJul 23, 06:25 UTC40m
2026-07-23 ZKNPK - Jul 23, 02:50 UTCJul 23, 04:40 UTC1h 50m
2026-07-22 ZKNPK - Jul 22, 23:45 UTCJul 23, 00:30 UTC45m
2026-07-22 ZKNPK NPE → NPE Jul 22, 21:40 UTCJul 22, 22:25 UTC45m
2026-07-22 ZKNPK - Jul 22, 04:20 UTCJul 22, 04:40 UTC20m
2026-07-22 ZKNPK - Jul 22, 03:00 UTCJul 22, 03:35 UTC35m
2026-07-22 ZKNPK NPE → NPE Jul 22, 01:15 UTCJul 22, 02:05 UTC50m
2026-07-22 ZKNPK - Jul 22, 00:15 UTCJul 22, 00:40 UTC25m
2026-07-21 ZKNPK - Jul 21, 22:45 UTCJul 21, 23:15 UTC30m
2026-07-21 ZKNPK - Jul 21, 21:45 UTCJul 21, 22:10 UTC25m
2026-07-21 ZKNPK - Jul 21, 07:35 UTCJul 21, 07:55 UTC20m
2026-07-21 ZKNPK NPE → NPE Jul 21, 05:55 UTCJul 21, 06:35 UTC40m
2026-07-21 ZKNPK - Jul 21, 04:30 UTCJul 21, 05:00 UTC30m
2026-07-21 ZKNPK - Jul 21, 03:30 UTCJul 21, 03:50 UTC20m
2026-07-21 ZKNPK - Jul 21, 01:45 UTCJul 21, 02:20 UTC35m
2026-07-21 ZKNPK - Jul 21, 00:25 UTCJul 21, 00:50 UTC25m
2026-07-20 ZKNPK - Jul 20, 22:25 UTCJul 20, 23:50 UTC1h 25m
2026-07-20 ZKNPK NPE → NPE Jul 20, 07:30 UTCJul 20, 08:05 UTC35m
2026-07-20 ZKNPK NPE → NPE Jul 20, 05:45 UTCJul 20, 06:30 UTC45m
2026-07-20 ZKNPK NPE → NPE Jul 20, 03:05 UTCJul 20, 03:35 UTC30m
2026-07-19 ZKNPK NPE → NPE Jul 19, 23:50 UTCJul 20, 00:25 UTC35m
2026-07-19 ZKNPK - Jul 19, 22:10 UTCJul 19, 22:55 UTC45m
2026-07-19 ZKNPK NPE → NPE Jul 19, 20:35 UTCJul 19, 21:20 UTC45m
2026-07-18 ZKNPK - Jul 18, 01:10 UTCJul 18, 04:45 UTC3h 36m
2026-07-17 ZKNPK - Jul 17, 21:55 UTCJul 17, 22:25 UTC30m
2026-07-17 ZKNPK NPE → NPE Jul 17, 01:25 UTCJul 17, 02:10 UTC45m
2026-07-16 ZKNPK NPE → NPE Jul 16, 23:25 UTCJul 17, 00:20 UTC55m
2026-07-16 ZKNPK NPE → NPE Jul 16, 03:20 UTCJul 16, 04:10 UTC50m
2026-07-16 ZKNPK NPE → NPE Jul 16, 02:20 UTCJul 16, 02:45 UTC25m
2026-07-16 ZKNPK - Jul 16, 00:45 UTCJul 16, 01:35 UTC50m
2026-07-15 ZKNPK - Jul 15, 23:20 UTCJul 16, 00:00 UTC40m
2026-07-15 ZKNPK - Jul 15, 21:05 UTCJul 15, 21:45 UTC40m
2026-07-15 ZKNPK - Jul 15, 08:50 UTCJul 15, 09:25 UTC35m
2026-07-15 ZKNPK NPE → NPE Jul 15, 07:30 UTCJul 15, 08:05 UTC35m
2026-07-15 ZKNPK WIR → NPE Jul 15, 04:00 UTCJul 15, 05:10 UTC1h 10m
2026-07-15 ZKNPK - Jul 15, 02:15 UTCJul 15, 02:40 UTC25m
2026-07-15 ZKNPK - Jul 15, 01:25 UTCJul 15, 01:45 UTC20m
2026-07-14 ZKNPK NPE → NPE Jul 14, 23:10 UTCJul 15, 00:00 UTC50m
2026-07-14 ZKNPK NPE → NPE Jul 14, 21:05 UTCJul 14, 21:55 UTC50m
2026-07-14 ZKNPK - Jul 14, 03:55 UTCJul 14, 05:20 UTC1h 25m
2026-07-14 ZKNPK - Jul 14, 02:10 UTCJul 14, 02:45 UTC35m
2026-07-14 ZKNPK NPE → NPE Jul 14, 01:10 UTCJul 14, 01:40 UTC30m
2026-07-13 ZKNPK NPE → NPE Jul 13, 23:50 UTCJul 14, 00:20 UTC30m
2026-07-13 ZKNPK NPE → NPE Jul 13, 21:35 UTCJul 13, 22:00 UTC25m
2026-07-13 ZKNPK NPE → NPE Jul 13, 08:35 UTCJul 13, 09:05 UTC30m

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 ZK-NPK page for operator, model, and routing details .

Mode-S C81C33 frequently asked

What is Mode-S code C81C33?
C81C33 is an ICAO 24-bit transponder address. Allocated to New Zealand. Assigned to ZK-NPK.
Where is Mode-S C81C33 registered?
Mode-S code C81C33 is allocated to New Zealand (NZ). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is C81C33 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 22:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex C81C33, octal 62016063, decimal 13,114,419.
What flights does C81C33 operate?
Mode-S C81C33 has broadcast 1 distinct callsign, including ZKNPK.