sensors Mode-S transponder

C81D6C

ICAO 24-bit transponder address · allocated to New Zealand

Currently assigned to ZK-ZAH · YAKOVLEV Yak-52

Hex
C81D6C
Octal
62016554
Decimal
13,114,732
Country
NZ
Tail
ZK-ZAH
Type
YK52
No current signal · last broadcast Jul 17, 03:45 UTC
Flights observed
2
Distinct callsigns
1
Country
NZ
Last broadcast
Jul 17, 03:45 UTC

Last known position

Most recent position reported by Mode-S C81D6C.

Country allocation

The ICAO 24-bit address C81D6C 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
ZKZAH - 2 2026-07-17

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-07-17 ZKZAH - Jul 17, 03:34 UTCJul 17, 03:45 UTC10m
2026-07-17 ZKZAH - Jul 17, 02:10 UTCJul 17, 02:30 UTC20m

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

Mode-S C81D6C frequently asked

What is Mode-S code C81D6C?
C81D6C is an ICAO 24-bit transponder address. Allocated to New Zealand. Assigned to ZK-ZAH.
Where is Mode-S C81D6C registered?
Mode-S code C81D6C 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 C81D6C broadcasting right now?
No active broadcast right now. Last signal was Jul 17, 03:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex C81D6C, octal 62016554, decimal 13,114,732.
What flights does C81D6C operate?
Mode-S C81D6C has broadcast 1 distinct callsign, including ZKZAH.