sensors Mode-S transponder
A6B4D0
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N531GX · CESSNA 525C Citation CJ4 · operated by TTR EXPRESS LLC, KLM OIL PROPERTIES LLC
- Hex
- A6B4D0
- Octal
- 51532320
- Decimal
- 10,925,264
- Country
- US
- Tail
- N531GX
- Type
- C25C
- Flights observed
- 47
- Distinct callsigns
- 1
- Country
- US
- Last broadcast
- Jul 21, 23:15 UTC
Current position
Country allocation
The ICAO 24-bit address A6B4D0 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 |
|---|---|---|---|
| N531GX | - | 47 | 2026-07-21 |
Recent flights last 47
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-21 | N531GX | - | Jul 21, 20:25 UTC | Jul 21, 23:15 UTC | 2h 50m |
| 2026-07-21 | N531GX | - | Jul 21, 18:25 UTC | Jul 21, 20:20 UTC | 1h 55m |
| 2026-07-21 | N531GX | - | Jul 21, 12:25 UTC | Jul 21, 16:20 UTC | 3h 55m |
| 2026-07-16 | N531GX | - | Jul 16, 16:19 UTC | Jul 16, 16:55 UTC | 35m |
| 2026-07-16 | N531GX | - | Jul 16, 14:45 UTC | Jul 16, 15:25 UTC | 40m |
| 2026-07-13 | N531GX | - | Jul 13, 17:10 UTC | Jul 13, 17:55 UTC | 45m |
| 2026-07-13 | N531GX | - | Jul 13, 15:15 UTC | Jul 13, 16:00 UTC | 45m |
| 2026-07-11 | N531GX | - | Jul 11, 14:55 UTC | Jul 11, 15:30 UTC | 35m |
| 2026-07-11 | N531GX | - | Jul 11, 13:05 UTC | Jul 11, 13:55 UTC | 50m |
| 2026-07-08 | N531GX | - | Jul 8, 21:15 UTC | Jul 8, 22:05 UTC | 50m |
| 2026-07-08 | N531GX | - | Jul 8, 16:55 UTC | Jul 8, 17:50 UTC | 55m |
| 2026-07-06 | N531GX | - | Jul 6, 17:45 UTC | Jul 6, 18:15 UTC | 30m |
| 2026-07-05 | N531GX | - | Jul 5, 20:35 UTC | Jul 6, 17:05 UTC | 20h 30m |
| 2026-07-01 | N531GX | - | Jul 1, 14:40 UTC | Jul 1, 15:40 UTC | 1h 0m |
| 2026-06-26 | N531GX | - | Jun 26, 17:54 UTC | Jun 26, 18:34 UTC | 40m |
| 2026-06-26 | N531GX | - | Jun 26, 14:39 UTC | Jun 26, 15:25 UTC | 45m |
| 2026-06-25 | N531GX | - | Jun 25, 20:59 UTC | Jun 25, 21:44 UTC | 45m |
| 2026-06-24 | N531GX | - | Jun 24, 21:09 UTC | Jun 24, 22:00 UTC | 50m |
| 2026-06-22 | N531GX | - | Jun 22, 17:10 UTC | Jun 22, 21:00 UTC | 3h 50m |
| 2026-06-22 | N531GX | - | Jun 22, 12:59 UTC | Jun 22, 16:24 UTC | 3h 25m |
| 2026-06-19 | N531GX | - | Jun 19, 16:09 UTC | Jun 19, 16:55 UTC | 45m |
| 2026-06-19 | N531GX | - | Jun 19, 14:39 UTC | Jun 19, 15:29 UTC | 50m |
| 2026-06-18 | N531GX | - | Jun 18, 14:35 UTC | Jun 18, 15:15 UTC | 40m |
| 2026-06-18 | N531GX | - | Jun 18, 13:25 UTC | Jun 18, 13:50 UTC | 25m |
| 2026-06-17 | N531GX | - | Jun 17, 20:40 UTC | Jun 17, 22:30 UTC | 1h 50m |
| 2026-06-17 | N531GX | - | Jun 17, 11:20 UTC | Jun 17, 13:30 UTC | 2h 10m |
| 2026-06-11 | N531GX | - | Jun 11, 18:35 UTC | Jun 11, 19:15 UTC | 40m |
| 2026-06-11 | N531GX | - | Jun 11, 14:05 UTC | Jun 11, 14:50 UTC | 45m |
| 2026-06-02 | N531GX | - | Jun 2, 20:35 UTC | Jun 2, 21:45 UTC | 1h 10m |
| 2026-06-02 | N531GX | - | Jun 2, 16:00 UTC | Jun 2, 17:15 UTC | 1h 15m |
| 2026-05-22 | N531GX | - | May 22, 20:00 UTC | May 22, 21:55 UTC | 1h 55m |
| 2026-05-21 | N531GX | - | May 21, 17:45 UTC | May 21, 18:30 UTC | 45m |
| 2026-05-21 | N531GX | - | May 21, 16:01 UTC | May 21, 16:50 UTC | 50m |
| 2026-05-20 | N531GX | - | May 20, 18:55 UTC | May 20, 19:20 UTC | 25m |
| 2026-05-20 | N531GX | - | May 20, 17:50 UTC | May 20, 18:15 UTC | 25m |
| 2026-05-18 | N531GX | - | May 18, 17:20 UTC | May 18, 18:40 UTC | 1h 19m |
| 2026-05-17 | N531GX | - | May 17, 16:15 UTC | May 17, 18:30 UTC | 2h 15m |
| 2026-05-15 | N531GX | - | May 15, 16:35 UTC | May 15, 19:00 UTC | 2h 25m |
| 2026-05-14 | N531GX | - | May 14, 18:55 UTC | May 14, 19:35 UTC | 40m |
| 2026-05-14 | N531GX | - | May 14, 15:20 UTC | May 14, 16:00 UTC | 40m |
| 2026-05-07 | N531GX | - | May 7, 22:45 UTC | May 7, 23:29 UTC | 45m |
| 2026-05-07 | N531GX | - | May 7, 17:50 UTC | May 7, 18:35 UTC | 45m |
| 2026-04-29 | N531GX | - | Apr 29, 22:20 UTC | Apr 29, 23:10 UTC | 49m |
| 2026-04-29 | N531GX | - | Apr 29, 15:20 UTC | Apr 29, 16:10 UTC | 50m |
| 2026-04-28 | N531GX | - | Apr 28, 03:20 UTC | Apr 28, 04:30 UTC | 1h 10m |
| 2026-04-24 | N531GX | - | Apr 24, 16:45 UTC | Apr 24, 18:25 UTC | 1h 40m |
| 2026-04-12 | N531GX | - | Apr 12, 17:50 UTC | Apr 12, 18:40 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 N531GX page for operator, model, and routing details .