sensors Mode-S transponder
C81D31
ICAO 24-bit transponder address · allocated to New Zealand
Currently assigned to ZK-MTS · DIAMOND DA-42 Guardian
- Hex
- C81D31
- Octal
- 62016461
- Decimal
- 13,114,673
- Country
- NZ
- Tail
- ZK-MTS
- Type
- DA42
- Flights observed
- 56
- Distinct callsigns
- 12
- Country
- NZ
- Last broadcast
- Jun 30, 02:45 UTC
Last known position
Country allocation
The ICAO 24-bit address C81D31 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 12 distinct
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-06-30 | MSY207 | - | Jun 30, 01:19 UTC | Jun 30, 02:45 UTC | 1h 26m |
| 2026-06-29 | MSY120 | - | Jun 29, 23:09 UTC | Jun 29, 23:29 UTC | 20m |
| 2026-06-29 | MSY120 | - | Jun 29, 21:44 UTC | Jun 29, 22:10 UTC | 25m |
| 2026-06-28 | MSY284 | - | Jun 28, 23:04 UTC | Jun 29, 00:14 UTC | 1h 10m |
| 2026-06-28 | MSY284 | - | Jun 28, 01:55 UTC | Jun 28, 02:25 UTC | 30m |
| 2026-06-27 | MSY284 | - | Jun 27, 22:40 UTC | Jun 27, 23:10 UTC | 30m |
| 2026-06-27 | MSY284 | - | Jun 27, 21:44 UTC | Jun 27, 21:55 UTC | 10m |
| 2026-06-26 | MSY120 | - | Jun 26, 21:30 UTC | Jun 26, 22:34 UTC | 1h 5m |
| 2026-06-24 | MSY30 | - | Jun 24, 21:29 UTC | Jun 24, 22:35 UTC | 1h 5m |
| 2026-06-24 | MSY124 | - | Jun 24, 03:00 UTC | Jun 24, 04:24 UTC | 1h 25m |
| 2026-06-23 | MSY604 | - | Jun 23, 21:29 UTC | Jun 23, 22:15 UTC | 45m |
| 2026-06-23 | MSY208 | - | Jun 23, 02:55 UTC | Jun 23, 04:05 UTC | 1h 10m |
| 2026-06-22 | MSY120 | - | Jun 22, 01:29 UTC | Jun 22, 03:10 UTC | 1h 40m |
| 2026-06-21 | MSY084 | - | Jun 21, 22:44 UTC | Jun 21, 23:59 UTC | 1h 15m |
| 2026-06-18 | MSY212 | - | Jun 18, 23:00 UTC | Jun 19, 00:00 UTC | 1h 0m |
| 2026-06-18 | MSY124 | - | Jun 18, 02:40 UTC | Jun 18, 03:20 UTC | 40m |
| 2026-06-18 | MSY212 | - | Jun 18, 00:50 UTC | Jun 18, 01:25 UTC | 35m |
| 2026-06-17 | MSY604 | PMR → PMR | Jun 17, 03:45 UTC | Jun 17, 04:45 UTC | 1h 0m |
| 2026-06-16 | MSY120 | - | Jun 16, 03:39 UTC | Jun 16, 04:55 UTC | 1h 15m |
| 2026-06-16 | MSY284 | - | Jun 16, 00:55 UTC | Jun 16, 01:04 UTC | 10m |
| 2026-06-15 | MSY284 | - | Jun 15, 23:30 UTC | Jun 15, 23:50 UTC | 20m |
| 2026-06-15 | MSY30 | - | Jun 15, 02:55 UTC | Jun 15, 03:30 UTC | 35m |
| 2026-06-09 | MSY604 | - | Jun 9, 21:15 UTC | Jun 9, 22:40 UTC | 1h 25m |
| 2026-06-09 | MSY16 | - | Jun 9, 00:35 UTC | Jun 9, 00:50 UTC | 15m |
| 2026-06-08 | MSY120 | - | Jun 8, 23:25 UTC | Jun 8, 23:40 UTC | 15m |
| 2026-06-08 | MSY120 | - | Jun 8, 22:45 UTC | Jun 8, 22:55 UTC | 10m |
| 2026-06-08 | MSY30 | - | Jun 8, 03:30 UTC | Jun 8, 04:40 UTC | 1h 10m |
| 2026-06-07 | MSY284 | - | Jun 7, 22:00 UTC | Jun 7, 22:40 UTC | 40m |
| 2026-06-07 | MSY292 | - | Jun 7, 03:40 UTC | Jun 7, 04:55 UTC | 1h 15m |
| 2026-06-06 | MSY30 | - | Jun 6, 23:15 UTC | Jun 7, 01:00 UTC | 1h 45m |
| 2026-06-01 | MSY292 | NPE → PMR | Jun 1, 01:20 UTC | Jun 1, 02:00 UTC | 40m |
| 2026-05-31 | MSY292 | PMR → NPE | May 31, 22:55 UTC | Jun 1, 00:40 UTC | 1h 45m |
| 2026-05-27 | MSY208 | - | May 27, 04:09 UTC | May 27, 04:59 UTC | 50m |
| 2026-05-26 | MSY120 | - | May 26, 03:19 UTC | May 26, 04:35 UTC | 1h 15m |
| 2026-05-26 | MSY292 | PMR → PMR | May 26, 01:10 UTC | May 26, 02:04 UTC | 55m |
| 2026-05-24 | MSY292 | PMR → PMR | May 24, 02:10 UTC | May 24, 03:45 UTC | 1h 35m |
| 2026-05-20 | MSY084 | - | May 20, 03:50 UTC | May 20, 05:10 UTC | 1h 21m |
| 2026-05-18 | MSY284 | - | May 18, 23:35 UTC | May 19, 00:50 UTC | 1h 15m |
| 2026-05-15 | MSY604 | - | May 15, 02:45 UTC | May 15, 03:45 UTC | 1h 0m |
| 2026-05-13 | MSY120 | - | May 13, 21:50 UTC | May 13, 22:45 UTC | 55m |
| 2026-05-13 | MSY292 | - | May 13, 02:55 UTC | May 13, 04:10 UTC | 1h 15m |
| 2026-05-12 | MSY604 | - | May 12, 03:10 UTC | May 12, 03:55 UTC | 45m |
| 2026-05-11 | MSY208 | - | May 11, 21:15 UTC | May 11, 22:35 UTC | 1h 19m |
| 2026-05-09 | MSY084 | - | May 9, 23:40 UTC | May 10, 00:30 UTC | 50m |
| 2026-05-09 | MSY084 | - | May 9, 22:39 UTC | May 9, 23:00 UTC | 20m |
| 2026-05-08 | MSY120 | - | May 8, 02:55 UTC | May 8, 04:34 UTC | 1h 40m |
| 2026-05-07 | MSY604 | PMR → PMR | May 7, 03:20 UTC | May 7, 04:30 UTC | 1h 10m |
| 2026-05-05 | MSY19 | - | May 5, 18:45 UTC | May 5, 19:40 UTC | 55m |
| 2026-04-28 | MSY084 | PMR → PMR | Apr 28, 21:19 UTC | Apr 28, 22:25 UTC | 1h 5m |
| 2026-04-28 | MSY120 | NPL → PMR | Apr 28, 03:45 UTC | Apr 28, 04:50 UTC | 1h 5m |
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-MTS page for operator, model, and routing details .