sensors Mode-S transponder
461F21
ICAO 24-bit transponder address · allocated to Finland
- Hex
- 461F21
- Octal
- 21417441
- Decimal
- 4,595,489
- Country
- FI
- Flights observed
- 36
- Distinct callsigns
- 14
- Country
- FI
- Last broadcast
- 8h ago
Last known position
Country allocation
The ICAO 24-bit address 461F21 falls within the block assigned to Finland (FI) by ICAO Annex 10, Volume III. Every aircraft registered in Finland 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 14 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| FIN84G | - | 12 | 2026-07-08 |
| FIN7AV | - | 4 | 2026-07-04 |
| FIN9BL | - | 3 | 2026-06-22 |
| FIN4EV | - | 3 | 2026-07-05 |
| FIN1RC | Finnair | 3 | 2026-06-25 |
| FIN6AK | - | 2 | 2026-06-18 |
| FIN1928 | Finnair | 2 | 2026-06-07 |
| FIN9DF | - | 1 | 2026-05-29 |
| FIN64K | Finnair | 1 | 2026-06-04 |
| FIN1AU | - | 1 | 2026-07-01 |
| FIN1935 | Finnair | 1 | 2026-06-10 |
| FIN1866 | Finnair | 1 | 2026-06-14 |
| FIN1858 | Finnair | 1 | 2026-05-31 |
| FIN1855 | - | 1 | 2026-07-03 |
Recent flights last 36
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-08 | FIN84G | - | Jul 8, 10:50 UTC | Jul 8, 11:15 UTC | 25m |
| 2026-07-07 | FIN84G | - | Jul 7, 04:55 UTC | Jul 7, 11:00 UTC | 6h 5m |
| 2026-07-05 | FIN4EV | - | Jul 5, 14:30 UTC | Jul 5, 21:20 UTC | 6h 50m |
| 2026-07-04 | FIN7AV | - | Jul 4, 05:05 UTC | Jul 4, 15:10 UTC | 10h 5m |
| 2026-07-03 | FIN1855 | - | Jul 3, 11:25 UTC | Jul 4, 10:15 UTC | 22h 50m |
| 2026-07-01 | FIN7AV | - | Jul 1, 20:55 UTC | Jul 2, 11:00 UTC | 14h 5m |
| 2026-07-01 | FIN7AV | - | Jul 1, 15:05 UTC | Jul 2, 11:00 UTC | 19h 55m |
| 2026-07-01 | FIN1AU | - | Jul 1, 05:00 UTC | Jul 1, 20:55 UTC | 15h 55m |
| 2026-06-28 | FIN84G | - | Jun 28, 04:59 UTC | Jun 28, 21:04 UTC | 16h 5m |
| 2026-06-27 | FIN84G | - | Jun 27, 20:19 UTC | Jun 28, 15:44 UTC | 19h 25m |
| 2026-06-27 | FIN84G | - | Jun 27, 20:09 UTC | Jun 28, 15:44 UTC | 19h 35m |
| 2026-06-27 | FIN84G | - | Jun 27, 14:29 UTC | Jun 28, 10:50 UTC | 20h 20m |
| 2026-06-25 | FIN84G | - | Jun 25, 20:14 UTC | Jun 26, 10:35 UTC | 14h 20m |
| 2026-06-25 | FIN84G | - | Jun 25, 14:39 UTC | Jun 26, 10:35 UTC | 19h 55m |
| 2026-06-25 | FIN1RC | HEL → VRN | Jun 25, 10:20 UTC | Jun 26, 10:15 UTC | 23h 55m |
| 2026-06-22 | FIN9BL | - | Jun 22, 15:05 UTC | Jun 23, 10:04 UTC | 19h 0m |
| 2026-06-22 | FIN84G | - | Jun 22, 10:19 UTC | Jun 23, 10:04 UTC | 23h 45m |
| 2026-06-22 | FIN84G | - | Jun 22, 04:49 UTC | Jun 22, 20:34 UTC | 15h 45m |
| 2026-06-21 | FIN84G | - | Jun 21, 14:34 UTC | Jun 22, 10:34 UTC | 20h 0m |
| 2026-06-18 | FIN6AK | - | Jun 18, 15:35 UTC | Jun 18, 21:10 UTC | 5h 35m |
| 2026-06-16 | FIN9BL | - | Jun 16, 15:20 UTC | Jun 16, 21:20 UTC | 6h 1m |
| 2026-06-14 | FIN1866 | RHO → HEL | Jun 14, 05:35 UTC | Jun 14, 21:20 UTC | 15h 45m |
| 2026-06-11 | FIN9BL | - | Jun 11, 14:45 UTC | Jun 11, 15:15 UTC | 30m |
| 2026-06-10 | FIN1935 | HEL → GZP | Jun 10, 14:45 UTC | Jun 10, 14:55 UTC | 10m |
| 2026-06-08 | FIN1RC | HEL → VRN | Jun 8, 14:40 UTC | Jun 8, 20:35 UTC | 5h 55m |
| 2026-06-07 | FIN1928 | LCA → HEL | Jun 7, 21:05 UTC | Jun 8, 20:15 UTC | 23h 10m |
| 2026-06-07 | FIN4EV | - | Jun 7, 14:20 UTC | Jun 7, 21:20 UTC | 7h 0m |
| 2026-06-04 | FIN64K | TIA → HEL | Jun 4, 14:25 UTC | Jun 4, 18:45 UTC | 4h 20m |
| 2026-06-02 | FIN7AV | CHQ → HEL | Jun 2, 10:00 UTC | Jun 2, 10:10 UTC | 10m |
| 2026-05-31 | FIN1858 | CHQ → HEL | May 31, 12:15 UTC | May 31, 22:05 UTC | 9h 50m |
| 2026-05-29 | FIN9DF | - | May 29, 15:35 UTC | May 29, 15:50 UTC | 15m |
| 2026-05-24 | FIN4EV | - | May 24, 14:45 UTC | May 24, 21:45 UTC | 7h 0m |
| 2026-05-21 | FIN6AK | CHQ → HEL | May 21, 15:00 UTC | May 21, 20:35 UTC | 5h 35m |
| 2026-05-17 | FIN1928 | LCA → HEL | May 17, 14:20 UTC | May 17, 21:05 UTC | 6h 45m |
| 2026-05-16 | FIN84G | RHO → HEL | May 16, 04:50 UTC | May 16, 10:40 UTC | 5h 51m |
| 2026-05-13 | FIN1RC | HEL → VRN | May 13, 19:55 UTC | May 13, 20:20 UTC | 25m |
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.