sensors Mode-S transponder
A1C743
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N21318 · PIPER PA-44 Seminole · operated by RAW RACING INC
- Hex
- A1C743
- Octal
- 50343503
- Decimal
- 10,602,307
- Country
- US
- Tail
- N21318
- Type
- PA44
- Flights observed
- 45
- Distinct callsigns
- 1
- Country
- US
- Last broadcast
- Jul 25, 23:00 UTC
Last known position
Country allocation
The ICAO 24-bit address A1C743 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States 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 |
|---|---|---|---|
| N21318 | - | 45 | 2026-07-25 |
Recent flights last 45
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-25 | N21318 | - | Jul 25, 22:50 UTC | Jul 25, 23:00 UTC | 10m |
| 2026-07-24 | N21318 | - | Jul 24, 00:10 UTC | Jul 24, 01:25 UTC | 1h 15m |
| 2026-07-22 | N21318 | - | Jul 22, 20:50 UTC | Jul 22, 21:40 UTC | 50m |
| 2026-07-21 | N21318 | - | Jul 21, 23:05 UTC | Jul 21, 23:50 UTC | 45m |
| 2026-07-21 | N21318 | - | Jul 21, 20:55 UTC | Jul 21, 21:45 UTC | 50m |
| 2026-07-20 | N21318 | - | Jul 20, 20:50 UTC | Jul 20, 22:05 UTC | 1h 15m |
| 2026-07-15 | N21318 | - | Jul 15, 20:40 UTC | Jul 15, 21:40 UTC | 1h 0m |
| 2026-07-14 | N21318 | - | Jul 14, 22:55 UTC | Jul 14, 23:45 UTC | 50m |
| 2026-07-14 | N21318 | - | Jul 14, 20:40 UTC | Jul 14, 21:30 UTC | 50m |
| 2026-07-07 | N21318 | - | Jul 7, 23:05 UTC | Jul 7, 23:50 UTC | 45m |
| 2026-07-07 | N21318 | - | Jul 7, 21:10 UTC | Jul 7, 21:45 UTC | 35m |
| 2026-07-02 | N21318 | - | Jul 2, 20:35 UTC | Jul 2, 21:25 UTC | 50m |
| 2026-07-01 | N21318 | - | Jul 1, 22:20 UTC | Jul 1, 23:40 UTC | 1h 20m |
| 2026-07-01 | N21318 | - | Jul 1, 17:40 UTC | Jul 1, 19:15 UTC | 1h 35m |
| 2026-06-30 | N21318 | - | Jun 30, 23:05 UTC | Jun 30, 23:40 UTC | 35m |
| 2026-06-30 | N21318 | - | Jun 30, 20:50 UTC | Jun 30, 22:10 UTC | 1h 20m |
| 2026-06-29 | N21318 | - | Jun 29, 00:34 UTC | Jun 29, 01:25 UTC | 50m |
| 2026-06-26 | N21318 | - | Jun 26, 00:39 UTC | Jun 26, 01:45 UTC | 1h 5m |
| 2026-06-24 | N21318 | - | Jun 24, 22:25 UTC | Jun 24, 23:40 UTC | 1h 15m |
| 2026-06-24 | N21318 | - | Jun 24, 20:54 UTC | Jun 24, 21:54 UTC | 1h 0m |
| 2026-06-24 | N21318 | - | Jun 24, 17:50 UTC | Jun 24, 18:44 UTC | 55m |
| 2026-06-24 | N21318 | - | Jun 24, 00:30 UTC | Jun 24, 01:14 UTC | 45m |
| 2026-06-23 | N21318 | - | Jun 23, 20:49 UTC | Jun 23, 21:34 UTC | 45m |
| 2026-06-21 | N21318 | - | Jun 21, 20:34 UTC | Jun 21, 21:39 UTC | 1h 5m |
| 2026-06-18 | N21318 | - | Jun 18, 20:40 UTC | Jun 18, 21:45 UTC | 1h 5m |
| 2026-06-17 | N21318 | - | Jun 17, 00:55 UTC | Jun 17, 01:45 UTC | 50m |
| 2026-06-16 | N21318 | - | Jun 16, 22:55 UTC | Jun 16, 23:40 UTC | 45m |
| 2026-05-12 | N21318 | - | May 12, 21:01 UTC | May 12, 21:45 UTC | 45m |
| 2026-05-09 | N21318 | - | May 9, 22:34 UTC | May 9, 23:30 UTC | 55m |
| 2026-05-09 | N21318 | - | May 9, 20:44 UTC | May 9, 21:30 UTC | 45m |
| 2026-05-08 | N21318 | - | May 8, 00:40 UTC | May 8, 01:40 UTC | 1h 0m |
| 2026-05-07 | N21318 | - | May 7, 23:29 UTC | May 7, 23:39 UTC | 10m |
| 2026-05-05 | N21318 | - | May 5, 21:01 UTC | May 5, 21:50 UTC | 50m |
| 2026-05-04 | N21318 | - | May 4, 20:45 UTC | May 4, 21:40 UTC | 55m |
| 2026-05-03 | N21318 | - | May 3, 23:04 UTC | May 4, 00:15 UTC | 1h 10m |
| 2026-05-02 | N21318 | - | May 2, 22:45 UTC | May 2, 23:40 UTC | 55m |
| 2026-05-02 | N21318 | - | May 2, 20:40 UTC | May 2, 21:35 UTC | 55m |
| 2026-04-30 | N21318 | - | Apr 30, 00:45 UTC | Apr 30, 01:40 UTC | 55m |
| 2026-04-27 | N21318 | - | Apr 27, 18:15 UTC | Apr 27, 19:05 UTC | 50m |
| 2026-04-26 | N21318 | - | Apr 26, 22:40 UTC | Apr 26, 23:35 UTC | 55m |
| 2026-04-26 | N21318 | - | Apr 26, 00:50 UTC | Apr 26, 01:35 UTC | 45m |
| 2026-04-23 | N21318 | - | Apr 23, 20:45 UTC | Apr 23, 21:45 UTC | 1h 0m |
| 2026-04-20 | N21318 | - | Apr 20, 00:25 UTC | Apr 20, 01:15 UTC | 50m |
| 2026-04-18 | N21318 | - | Apr 18, 17:50 UTC | Apr 18, 18:45 UTC | 55m |
| 2026-04-16 | N21318 | - | Apr 16, 17:50 UTC | Apr 16, 18:30 UTC | 40m |
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 N21318 page for operator, model, and routing details .