sensors Mode-S transponder

C81D1B

ICAO 24-bit transponder address · allocated to New Zealand

Currently assigned to ZK-TUT · CESSNA 152

Hex
C81D1B
Octal
62016433
Decimal
13,114,651
Country
NZ
Tail
ZK-TUT
Type
C152
No current signal · last broadcast 1d ago
Flights observed
98
Distinct callsigns
1
Country
NZ
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S C81D1B.

Country allocation

The ICAO 24-bit address C81D1B 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
ZKTUT - 98 2026-05-29

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 ZKTUT - May 29, 03:40 UTCMay 29, 04:10 UTC30m
2026-05-29 ZKTUT - May 29, 02:05 UTCMay 29, 02:25 UTC20m
2026-05-28 ZKTUT NPE → NPE May 28, 21:55 UTCMay 28, 22:40 UTC45m
2026-05-28 ZKTUT - May 28, 01:30 UTCMay 28, 01:45 UTC15m
2026-05-28 ZKTUT - May 28, 00:10 UTCMay 28, 00:55 UTC45m
2026-05-27 ZKTUT NPE → NPE May 27, 21:15 UTCMay 27, 22:30 UTC1h 15m
2026-05-27 ZKTUT - May 27, 07:20 UTCMay 27, 07:40 UTC20m
2026-05-27 ZKTUT NPE → NPE May 27, 05:59 UTCMay 27, 06:44 UTC45m
2026-05-27 ZKTUT - May 27, 02:19 UTCMay 27, 04:04 UTC1h 45m
2026-05-26 ZKTUT - May 26, 22:25 UTCMay 26, 23:19 UTC55m
2026-05-26 ZKTUT NPE → NPE May 26, 21:20 UTCMay 26, 21:40 UTC20m
2026-05-26 ZKTUT - May 26, 01:30 UTCMay 26, 01:44 UTC15m
2026-05-26 ZKTUT - May 26, 00:04 UTCMay 26, 00:44 UTC40m
2026-05-25 ZKTUT - May 25, 23:00 UTCMay 25, 23:30 UTC30m
2026-05-25 ZKTUT NPE → NPE May 25, 20:34 UTCMay 25, 20:59 UTC25m
2026-05-25 ZKTUT - May 25, 05:55 UTCMay 25, 06:40 UTC45m
2026-05-25 ZKTUT - May 25, 02:00 UTCMay 25, 03:50 UTC1h 50m
2026-05-24 ZKTUT NPE → NPE May 24, 23:00 UTCMay 24, 23:15 UTC15m
2026-05-24 ZKTUT - May 24, 21:00 UTCMay 24, 21:35 UTC35m
2026-05-22 ZKTUT NPE → NPE May 22, 03:55 UTCMay 22, 04:45 UTC50m
2026-05-22 ZKTUT - May 22, 02:55 UTCMay 22, 03:10 UTC15m
2026-05-21 ZKTUT NPE → NPE May 21, 23:10 UTCMay 21, 23:50 UTC40m
2026-05-21 ZKTUT - May 21, 22:00 UTCMay 21, 22:30 UTC30m
2026-05-21 ZKTUT NPE → NPE May 21, 20:25 UTCMay 21, 21:10 UTC45m
2026-05-21 ZKTUT - May 21, 03:25 UTCMay 21, 04:15 UTC50m
2026-05-21 ZKTUT - May 21, 01:45 UTCMay 21, 02:05 UTC20m
2026-05-20 ZKTUT NPE → NPE May 20, 23:00 UTCMay 20, 23:45 UTC45m
2026-05-20 ZKTUT NPE → NPE May 20, 21:15 UTCMay 20, 22:10 UTC55m
2026-05-20 ZKTUT - May 20, 03:15 UTCMay 20, 04:55 UTC1h 41m
2026-05-20 ZKTUT NPE → NPE May 20, 01:10 UTCMay 20, 02:10 UTC1h 0m
2026-05-20 ZKTUT - May 20, 00:00 UTCMay 20, 00:15 UTC15m
2026-05-15 ZKTUT - May 15, 03:25 UTCMay 15, 04:10 UTC45m
2026-05-14 ZKTUT - May 14, 05:40 UTCMay 14, 08:30 UTC2h 50m
2026-05-14 ZKTUT - May 14, 04:05 UTCMay 14, 04:35 UTC30m
2026-05-14 ZKTUT - May 14, 02:40 UTCMay 14, 03:15 UTC35m
2026-05-14 ZKTUT - May 14, 01:00 UTCMay 14, 01:45 UTC45m
2026-05-12 ZKTUT - May 12, 21:35 UTCMay 12, 22:01 UTC25m
2026-05-12 ZKTUT - May 12, 20:40 UTCMay 12, 21:05 UTC25m
2026-05-12 ZKTUT - May 12, 04:35 UTCMay 12, 05:30 UTC55m
2026-05-12 ZKTUT - May 12, 03:00 UTCMay 12, 03:50 UTC50m
2026-05-11 ZKTUT - May 11, 21:15 UTCMay 11, 22:00 UTC45m
2026-05-11 ZKTUT - May 11, 02:40 UTCMay 11, 04:00 UTC1h 20m
2026-05-11 ZKTUT - May 11, 00:15 UTCMay 11, 00:54 UTC40m
2026-05-10 ZKTUT - May 10, 22:20 UTCMay 10, 22:40 UTC20m
2026-05-10 ZKTUT - May 10, 20:50 UTCMay 10, 21:35 UTC45m
2026-05-05 ZKTUT - May 5, 06:05 UTCMay 5, 07:30 UTC1h 25m
2026-05-05 ZKTUT - May 5, 04:15 UTCMay 5, 05:05 UTC50m
2026-05-05 ZKTUT - May 5, 02:35 UTCMay 5, 03:05 UTC30m
2026-05-05 ZKTUT - May 5, 01:25 UTCMay 5, 02:05 UTC40m
2026-05-04 ZKTUT - May 4, 23:35 UTCMay 5, 00:05 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-TUT page for operator, model, and routing details .

Mode-S C81D1B frequently asked

What is Mode-S code C81D1B?
C81D1B is an ICAO 24-bit transponder address. Allocated to New Zealand. Assigned to ZK-TUT.
Where is Mode-S C81D1B registered?
Mode-S code C81D1B 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 C81D1B broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex C81D1B, octal 62016433, decimal 13,114,651.
What flights does C81D1B operate?
Mode-S C81D1B has broadcast 1 distinct callsign, including ZKTUT.