sensors Mode-S transponder
A68E37
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N521SB · GULFSTREAM 5 · operated by BANK OF UTAH TRUSTEE
- Hex
- A68E37
- Octal
- 51507067
- Decimal
- 10,915,383
- Country
- US
- Tail
- N521SB
- Type
- GLF5
- Flights observed
- 43
- Distinct callsigns
- 1
- Country
- US
- Last broadcast
- Jul 25, 22:05 UTC
Last known position
Country allocation
The ICAO 24-bit address A68E37 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 |
|---|---|---|---|
| CWG521 | - | 43 | 2026-07-25 |
Recent flights last 43
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-25 | CWG521 | - | Jul 25, 17:05 UTC | Jul 25, 22:05 UTC | 5h 0m |
| 2026-07-20 | CWG521 | - | Jul 20, 20:00 UTC | Jul 20, 23:00 UTC | 3h 0m |
| 2026-07-17 | CWG521 | - | Jul 17, 22:29 UTC | Jul 17, 22:40 UTC | 10m |
| 2026-07-17 | CWG521 | - | Jul 17, 19:25 UTC | Jul 17, 21:55 UTC | 2h 30m |
| 2026-07-17 | CWG521 | - | Jul 17, 10:50 UTC | Jul 17, 17:50 UTC | 7h 0m |
| 2026-07-17 | CWG521 | - | Jul 17, 09:55 UTC | Jul 17, 10:44 UTC | 50m |
| 2026-07-12 | CWG521 | - | Jul 12, 12:35 UTC | Jul 12, 13:55 UTC | 1h 20m |
| 2026-06-25 | CWG521 | IAD → LTN | Jun 25, 23:55 UTC | Jun 26, 06:39 UTC | 6h 45m |
| 2026-06-24 | CWG521 | - | Jun 24, 00:05 UTC | Jun 24, 00:55 UTC | 50m |
| 2026-06-20 | CWG521 | - | Jun 20, 02:19 UTC | Jun 20, 05:09 UTC | 2h 50m |
| 2026-06-18 | CWG521 | - | Jun 18, 17:25 UTC | Jun 18, 20:35 UTC | 3h 10m |
| 2026-06-15 | CWG521 | AUS → TEB | Jun 15, 18:55 UTC | Jun 15, 21:45 UTC | 2h 50m |
| 2026-06-12 | CWG521 | SFO → AUS | Jun 12, 01:30 UTC | Jun 12, 04:30 UTC | 3h 0m |
| 2026-06-11 | CWG521 | AUS → SFO | Jun 11, 15:45 UTC | Jun 11, 19:05 UTC | 3h 20m |
| 2026-06-10 | CWG521 | - | Jun 10, 22:50 UTC | Jun 10, 23:15 UTC | 25m |
| 2026-05-30 | CWG521 | - | May 30, 21:10 UTC | May 30, 21:35 UTC | 25m |
| 2026-05-30 | CWG521 | - | May 30, 20:00 UTC | May 30, 20:35 UTC | 35m |
| 2026-05-30 | CWG521 | AUS → DAL | May 30, 12:25 UTC | May 30, 13:05 UTC | 40m |
| 2026-05-29 | CWG521 | - | May 29, 22:50 UTC | May 29, 23:20 UTC | 30m |
| 2026-05-25 | CWG521 | - | May 25, 22:05 UTC | May 25, 22:34 UTC | 30m |
| 2026-05-25 | CWG521 | - | May 25, 18:10 UTC | May 25, 21:09 UTC | 2h 59m |
| 2026-05-20 | CWG521 | AUS → APC | May 20, 21:50 UTC | May 21, 01:10 UTC | 3h 20m |
| 2026-05-17 | CWG521 | - | May 17, 23:40 UTC | May 18, 01:20 UTC | 1h 40m |
| 2026-05-17 | CWG521 | YYC → DEN | May 17, 21:05 UTC | May 17, 23:00 UTC | 1h 55m |
| 2026-05-12 | CWG521 | - | May 12, 22:05 UTC | May 13, 02:30 UTC | 4h 25m |
| 2026-05-12 | CWG521 | AUS → PHF | May 12, 16:15 UTC | May 12, 18:40 UTC | 2h 25m |
| 2026-05-11 | CWG521 | VNY → AUS | May 11, 16:20 UTC | May 11, 18:50 UTC | 2h 31m |
| 2026-05-08 | CWG521 | AUS → VNY | May 8, 20:10 UTC | May 8, 22:55 UTC | 2h 45m |
| 2026-05-08 | CWG521 | - | May 8, 18:10 UTC | May 8, 18:35 UTC | 25m |
| 2026-05-06 | CWG521 | - | May 6, 20:55 UTC | May 6, 22:30 UTC | 1h 35m |
| 2026-05-04 | CWG521 | - | May 4, 14:20 UTC | May 4, 16:00 UTC | 1h 40m |
| 2026-05-02 | CWG521 | - | May 2, 20:35 UTC | May 2, 20:55 UTC | 20m |
| 2026-05-02 | CWG521 | - | May 2, 17:10 UTC | May 2, 19:55 UTC | 2h 45m |
| 2026-04-30 | CWG521 | AUS → OPF | Apr 30, 13:10 UTC | Apr 30, 15:15 UTC | 2h 5m |
| 2026-04-29 | CWG521 | - | Apr 29, 22:00 UTC | Apr 29, 22:30 UTC | 30m |
| 2026-04-24 | CWG521 | - | Apr 24, 13:35 UTC | Apr 24, 14:05 UTC | 30m |
| 2026-04-24 | CWG521 | HNL → AUS | Apr 24, 06:05 UTC | Apr 24, 12:35 UTC | 6h 30m |
| 2026-04-18 | CWG521 | - | Apr 18, 14:20 UTC | Apr 18, 14:35 UTC | 15m |
| 2026-04-18 | CWG521 | - | Apr 18, 07:25 UTC | Apr 18, 09:20 UTC | 1h 55m |
| 2026-04-18 | CWG521 | - | Apr 18, 05:25 UTC | Apr 18, 07:20 UTC | 1h 55m |
| 2026-04-18 | CWG521 | - | Apr 18, 04:45 UTC | Apr 18, 06:40 UTC | 1h 55m |
| 2026-04-18 | CWG521 | - | Apr 18, 03:45 UTC | Apr 18, 09:40 UTC | 5h 55m |
| 2026-04-18 | CWG521 | - | Apr 18, 01:45 UTC | Apr 18, 01:55 UTC | 10m |
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 N521SB page for operator, model, and routing details .