sensors Mode-S transponder
AFC66A
ICAO 24-bit transponder address
Currently assigned to 24-21306 · SIKORSKY UH-60 Black Hawk
- Hex
- AFC66A
- Octal
- 53743152
- Decimal
- 11,519,594
- Tail
- 24-21306
- Type
- H60
- Flights observed
- 19
- Distinct callsigns
- 1
- Country
- -
- Last broadcast
- Jul 17, 02:05 UTC
Last known position
Callsign history 1 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| G21306 | - | 19 | 2026-07-17 |
Recent flights last 19
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-17 | G21306 | ILG → ILG | Jul 17, 00:14 UTC | Jul 17, 02:05 UTC | 1h 50m |
| 2026-07-16 | G21306 | - | Jul 16, 20:25 UTC | Jul 16, 21:15 UTC | 50m |
| 2026-07-16 | G21306 | - | Jul 16, 19:40 UTC | Jul 16, 20:19 UTC | 40m |
| 2026-07-15 | G21306 | - | Jul 15, 00:40 UTC | Jul 15, 02:10 UTC | 1h 30m |
| 2026-06-30 | G21306 | - | Jun 30, 17:05 UTC | Jun 30, 18:55 UTC | 1h 50m |
| 2026-06-26 | G21306 | - | Jun 26, 02:00 UTC | Jun 26, 02:09 UTC | 10m |
| 2026-06-26 | G21306 | - | Jun 26, 00:15 UTC | Jun 26, 01:20 UTC | 1h 5m |
| 2026-06-25 | G21306 | - | Jun 25, 19:15 UTC | Jun 25, 20:49 UTC | 1h 35m |
| 2026-06-25 | G21306 | - | Jun 25, 00:24 UTC | Jun 25, 02:14 UTC | 1h 50m |
| 2026-06-24 | G21306 | - | Jun 24, 17:45 UTC | Jun 24, 19:29 UTC | 1h 45m |
| 2026-06-24 | G21306 | - | Jun 24, 00:30 UTC | Jun 24, 02:20 UTC | 1h 50m |
| 2026-06-16 | G21306 | - | Jun 16, 20:40 UTC | Jun 16, 22:25 UTC | 1h 45m |
| 2026-04-24 | G21306 | ILG → ILG | Apr 24, 16:05 UTC | Apr 24, 17:30 UTC | 1h 25m |
| 2026-04-24 | G21306 | - | Apr 24, 01:05 UTC | Apr 24, 01:45 UTC | 40m |
| 2026-04-23 | G21306 | - | Apr 23, 23:50 UTC | Apr 24, 00:15 UTC | 25m |
| 2026-04-23 | G21306 | - | Apr 23, 19:05 UTC | Apr 23, 19:30 UTC | 25m |
| 2026-04-23 | G21306 | - | Apr 23, 17:45 UTC | Apr 23, 18:00 UTC | 15m |
| 2026-04-17 | G21306 | - | Apr 17, 00:30 UTC | Apr 17, 01:10 UTC | 40m |
| 2026-04-16 | G21306 | - | Apr 16, 21:14 UTC | Apr 16, 22:34 UTC | 1h 20m |
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 24-21306 page for operator, model, and routing details .