sensors Mode-S transponder
A16D8F
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N191TD · LEARJET 45 · operated by RICHARDS AVIATION INC, M&S AVIATION INC, RIVERWATCH WINGS LLC
- Hex
- A16D8F
- Octal
- 50266617
- Decimal
- 10,579,343
- Country
- US
- Tail
- N191TD
- Type
- LJ45
- Flights observed
- 37
- Distinct callsigns
- 1
- Country
- US
- Last broadcast
- 1d ago
Last known position
Country allocation
The ICAO 24-bit address A16D8F 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 |
|---|---|---|---|
| N191TD | - | 37 | 2026-07-19 |
Recent flights last 37
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-19 | N191TD | - | Jul 19, 20:20 UTC | Jul 19, 21:10 UTC | 50m |
| 2026-07-19 | N191TD | - | Jul 19, 18:40 UTC | Jul 19, 19:40 UTC | 1h 0m |
| 2026-07-17 | N191TD | - | Jul 17, 22:25 UTC | Jul 17, 23:20 UTC | 55m |
| 2026-07-17 | N191TD | AUO → TPA | Jul 17, 20:35 UTC | Jul 17, 21:44 UTC | 1h 10m |
| 2026-07-01 | N191TD | - | Jul 1, 18:10 UTC | Jul 1, 20:25 UTC | 2h 15m |
| 2026-07-01 | N191TD | - | Jul 1, 15:05 UTC | Jul 1, 17:25 UTC | 2h 20m |
| 2026-06-26 | N191TD | - | Jun 26, 20:29 UTC | Jun 26, 21:20 UTC | 50m |
| 2026-06-26 | N191TD | AUO → AUO | Jun 26, 11:40 UTC | Jun 26, 19:39 UTC | 8h 0m |
| 2026-06-25 | N191TD | AUO → AUO | Jun 25, 00:40 UTC | Jun 25, 02:14 UTC | 1h 35m |
| 2026-06-22 | N191TD | AUO → AUO | Jun 22, 13:54 UTC | Jun 22, 23:20 UTC | 9h 25m |
| 2026-06-20 | N191TD | IAD → AUO | Jun 20, 21:10 UTC | Jun 20, 22:45 UTC | 1h 35m |
| 2026-06-18 | N191TD | AUO → IAD | Jun 18, 11:30 UTC | Jun 18, 13:00 UTC | 1h 30m |
| 2026-06-17 | N191TD | - | Jun 17, 02:40 UTC | Jun 17, 03:15 UTC | 35m |
| 2026-06-16 | N191TD | - | Jun 16, 22:00 UTC | Jun 16, 22:35 UTC | 35m |
| 2026-06-14 | N191TD | - | Jun 14, 23:15 UTC | Jun 15, 00:45 UTC | 1h 30m |
| 2026-06-14 | N191TD | - | Jun 14, 11:35 UTC | Jun 14, 13:15 UTC | 1h 40m |
| 2026-06-13 | N191TD | - | Jun 13, 22:30 UTC | Jun 13, 23:20 UTC | 50m |
| 2026-06-13 | N191TD | - | Jun 13, 19:05 UTC | Jun 13, 19:55 UTC | 50m |
| 2026-06-12 | N191TD | TPA → AUO | Jun 12, 01:35 UTC | Jun 12, 02:25 UTC | 50m |
| 2026-06-11 | N191TD | AUO → TPA | Jun 11, 22:55 UTC | Jun 11, 23:45 UTC | 50m |
| 2026-06-11 | N191TD | - | Jun 11, 16:05 UTC | Jun 11, 16:55 UTC | 50m |
| 2026-06-11 | N191TD | - | Jun 11, 14:35 UTC | Jun 11, 15:30 UTC | 55m |
| 2026-06-06 | N191TD | - | Jun 6, 23:15 UTC | Jun 6, 23:55 UTC | 40m |
| 2026-06-06 | N191TD | - | Jun 6, 20:19 UTC | Jun 6, 22:20 UTC | 2h 0m |
| 2026-06-05 | N191TD | - | Jun 5, 18:10 UTC | Jun 5, 20:00 UTC | 1h 50m |
| 2026-06-05 | N191TD | - | Jun 5, 15:35 UTC | Jun 5, 16:25 UTC | 50m |
| 2026-06-01 | N191TD | TPA → AUO | Jun 1, 17:00 UTC | Jun 1, 17:50 UTC | 50m |
| 2026-06-01 | N191TD | - | Jun 1, 15:10 UTC | Jun 1, 16:05 UTC | 55m |
| 2026-05-23 | N191TD | - | May 23, 21:10 UTC | May 23, 22:05 UTC | 55m |
| 2026-05-23 | N191TD | - | May 23, 16:45 UTC | May 23, 17:35 UTC | 50m |
| 2026-05-22 | N191TD | - | May 22, 16:00 UTC | May 22, 17:10 UTC | 1h 10m |
| 2026-04-20 | N191TD | - | Apr 20, 01:15 UTC | Apr 20, 03:20 UTC | 2h 5m |
| 2026-04-19 | N191TD | - | Apr 19, 23:30 UTC | Apr 20, 00:25 UTC | 55m |
| 2026-04-19 | N191TD | AUO → TPA | Apr 19, 22:00 UTC | Apr 19, 22:55 UTC | 55m |
| 2026-04-17 | N191TD | - | Apr 17, 21:25 UTC | Apr 17, 22:00 UTC | 35m |
| 2026-04-17 | N191TD | - | Apr 17, 21:10 UTC | Apr 17, 21:20 UTC | 10m |
| 2026-04-17 | N191TD | AUO → TPA | Apr 17, 19:40 UTC | Apr 17, 20:30 UTC | 50m |
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 N191TD page for operator, model, and routing details .