sensors Mode-S transponder

C81CEF

ICAO 24-bit transponder address · allocated to New Zealand

Currently assigned to ZK-MTC · DIAMOND DA-40 Club Star

Hex
C81CEF
Octal
62016357
Decimal
13,114,607
Country
NZ
Tail
ZK-MTC
Type
DA40
No current signal · last broadcast 10h ago
Flights observed
102
Distinct callsigns
20
Country
NZ
Last broadcast
10h ago

Last known position

Most recent position reported by Mode-S C81CEF.

Country allocation

The ICAO 24-bit address C81CEF 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 20 distinct

Callsign Airline Flights Last seen
MSY624 - 6 2026-05-23
MSY465 - 5 2026-05-23
MSY487 - 4 2026-04-28
MSY653 - 3 2026-05-11
MSY635 - 3 2026-05-30
MSY627 - 3 2026-05-02
MSY626 - 3 2026-05-12
MSY621 - 3 2026-05-06
MSY470 - 3 2026-04-22
MSY956 - 2 2026-05-11
MSY654 - 2 2026-05-03
MSY651 - 2 2026-05-26
MSY647 - 2 2026-05-05
MSY645 - 2 2026-05-07
MSY642 - 2 2026-05-10
MSY640 - 2 2026-05-28
MSY638 - 2 2026-05-24
MSY632 - 2 2026-05-26
MSY631 - 2 2026-05-21
MSY630 - 2 2026-05-22

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-03 MSY27 - Jun 3, 03:45 UTCJun 3, 04:25 UTC40m
2026-05-30 MSY637 - May 30, 22:45 UTCMay 30, 23:50 UTC1h 5m
2026-05-30 MSY633 - May 30, 20:25 UTCMay 30, 21:25 UTC1h 0m
2026-05-30 MSY635 - May 30, 03:20 UTCMay 30, 04:20 UTC1h 0m
2026-05-29 MSY488 - May 29, 21:50 UTCMay 29, 22:50 UTC1h 0m
2026-05-29 MSY644 PMR → PMR May 29, 03:55 UTCMay 29, 04:45 UTC50m
2026-05-28 MSY640 - May 28, 22:55 UTCMay 29, 00:00 UTC1h 5m
2026-05-27 MSY489 - May 27, 03:04 UTCMay 27, 03:14 UTC10m
2026-05-27 MSY489 - May 27, 02:09 UTCMay 27, 02:19 UTC10m
2026-05-27 MSY481 PMR → PMR May 27, 00:19 UTCMay 27, 00:59 UTC40m
2026-05-26 MSY651 - May 26, 22:25 UTCMay 26, 23:29 UTC1h 5m
2026-05-26 MSY632 - May 26, 20:20 UTCMay 26, 21:29 UTC1h 10m
2026-05-26 MSY124 - May 26, 06:10 UTCMay 26, 06:59 UTC50m
2026-05-26 MSY628 PMR → PMR May 26, 02:24 UTCMay 26, 03:00 UTC35m
2026-05-24 MSY635 - May 24, 23:15 UTCMay 24, 23:40 UTC25m
2026-05-24 MSY650 PMR → PMR May 24, 20:55 UTCMay 24, 21:40 UTC45m
2026-05-24 MSY485 - May 24, 03:50 UTCMay 24, 04:15 UTC25m
2026-05-24 MSY638 - May 24, 00:05 UTCMay 24, 01:00 UTC55m
2026-05-23 MSY465 - May 23, 21:40 UTCMay 23, 21:50 UTC10m
2026-05-23 MSY624 PMR → PMR May 23, 01:55 UTCMay 23, 02:50 UTC54m
2026-05-22 MSY639 - May 22, 23:30 UTCMay 22, 23:40 UTC10m
2026-05-22 MSY630 - May 22, 20:20 UTCMay 22, 21:25 UTC1h 5m
2026-05-22 MSY208 - May 22, 06:20 UTCMay 22, 07:30 UTC1h 10m
2026-05-21 MSY518 - May 21, 23:50 UTCMay 22, 00:00 UTC10m
2026-05-21 MSY631 - May 21, 22:20 UTCMay 21, 22:30 UTC10m
2026-05-21 MSY631 - May 21, 21:30 UTCMay 21, 21:40 UTC10m
2026-05-14 MSY091 - May 14, 23:15 UTCMay 15, 00:20 UTC1h 5m
2026-05-12 MSY469 - May 12, 22:20 UTCMay 12, 23:05 UTC45m
2026-05-12 MSY626 - May 12, 04:10 UTCMay 12, 04:35 UTC25m
2026-05-11 MSY624 PMR → PMR May 11, 22:10 UTCMay 11, 22:35 UTC24m
2026-05-11 MSY653 PMR → PMR May 11, 20:35 UTCMay 11, 21:15 UTC40m
2026-05-11 MSY956 - May 11, 03:05 UTCMay 11, 03:20 UTC15m
2026-05-11 MSY956 - May 11, 01:30 UTCMay 11, 02:10 UTC40m
2026-05-10 MSY512 - May 10, 23:15 UTCMay 10, 23:50 UTC35m
2026-05-10 MSY642 - May 10, 01:30 UTCMay 10, 01:39 UTC10m
2026-05-09 MSY632 - May 9, 22:55 UTCMay 9, 23:05 UTC10m
2026-05-07 MSY645 - May 7, 02:55 UTCMay 7, 03:05 UTC10m
2026-05-06 MSY622 PMR → PMR May 6, 23:50 UTCMay 7, 00:30 UTC40m
2026-05-06 MSY621 PMR → PMR May 6, 21:15 UTCMay 6, 21:30 UTC15m
2026-05-06 MSY207 - May 6, 06:25 UTCMay 6, 07:10 UTC45m
2026-05-06 MSY483 - May 6, 03:25 UTCMay 6, 04:00 UTC35m
2026-05-06 MSY465 - May 6, 00:35 UTCMay 6, 01:05 UTC30m
2026-05-05 MSY465 - May 5, 23:40 UTCMay 5, 23:55 UTC15m
2026-05-05 MSY642 - May 5, 21:55 UTCMay 5, 22:30 UTC35m
2026-05-05 MSY281 PMR → PMR May 5, 06:15 UTCMay 5, 07:15 UTC1h 0m
2026-05-05 MSY653 PMR → PMR May 5, 04:10 UTCMay 5, 04:55 UTC45m
2026-05-05 MSY647 - May 5, 02:40 UTCMay 5, 03:25 UTC45m
2026-05-05 MSY479 - May 5, 01:15 UTCMay 5, 01:30 UTC15m
2026-05-04 MSY42 - May 4, 22:50 UTCMay 4, 23:40 UTC50m
2026-05-04 MSY640 PMR → PMR May 4, 20:55 UTCMay 4, 21:55 UTC1h 0m

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

Mode-S C81CEF frequently asked

What is Mode-S code C81CEF?
C81CEF is an ICAO 24-bit transponder address. Allocated to New Zealand. Assigned to ZK-MTC.
Where is Mode-S C81CEF registered?
Mode-S code C81CEF 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 C81CEF broadcasting right now?
No active broadcast right now. Last signal was 10h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex C81CEF, octal 62016357, decimal 13,114,607.
What flights does C81CEF operate?
Mode-S C81CEF has broadcast 20 distinct callsigns, including MSY624, MSY465, MSY487, MSY653, MSY635.