sensors Mode-S transponder

C81CE5

ICAO 24-bit transponder address · allocated to New Zealand

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

Hex
C81CE5
Octal
62016345
Decimal
13,114,597
Country
NZ
Tail
ZK-MTG
Type
DA40
Broadcasting now · callsign MSY645 · 1,100 ft
Flights observed
3
Distinct callsigns
3
Country
NZ
Last broadcast
1d ago

Current position

C81CE5 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address C81CE5 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 3 distinct

Callsign Airline Flights Last seen
MSY639 - 1 2026-04-15
MSY637 - 1 2026-04-16
MSY514 - 1 2026-04-17

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-17 MSY514 - Apr 17, 04:45 UTCApr 17, 04:55 UTC10m
2026-04-16 MSY637 - Apr 16, 03:45 UTCApr 16, 04:29 UTC45m
2026-04-15 MSY639 PMR → PMR Apr 15, 03:20 UTCApr 15, 04:00 UTC40m

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

Mode-S C81CE5 frequently asked

What is Mode-S code C81CE5?
C81CE5 is an ICAO 24-bit transponder address. Allocated to New Zealand. Assigned to ZK-MTG.
Where is Mode-S C81CE5 registered?
Mode-S code C81CE5 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 C81CE5 broadcasting right now?
Yes. Mode-S C81CE5 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex C81CE5, octal 62016345, decimal 13,114,597.
What flights does C81CE5 operate?
Mode-S C81CE5 has broadcast 3 distinct callsigns, including MSY639, MSY637, MSY514.