sensors Mode-S transponder
A22D9F
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N23994 · BOEING 787-9 Dreamliner · operated by UNITED AIRLINES INC
- Hex
- A22D9F
- Octal
- 50426637
- Decimal
- 10,628,511
- Country
- US
- Tail
- N23994
- Type
- B789
- Flights observed
- 116
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 1h ago
Last known position
Country allocation
The ICAO 24-bit address A22D9F 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 20 distinct
| Callsign | Airline | Flights | Last seen |
|---|---|---|---|
| UAL821 | United Airlines | 10 | 2026-05-22 |
| UAL199 | United Airlines | 8 | 2026-05-29 |
| UAL820 | United Airlines | 7 | 2026-05-22 |
| UAL152 | United Airlines | 7 | 2026-05-27 |
| UAL198 | United Airlines | 5 | 2026-05-28 |
| UAL79 | United Airlines | 4 | 2026-04-18 |
| UAL772 | United Airlines | 4 | 2026-04-16 |
| UAL771 | United Airlines | 4 | 2026-04-15 |
| UAL178 | United Airlines | 4 | 2026-04-26 |
| UAL153 | United Airlines | 4 | 2026-05-28 |
| UAL63 | United Airlines | 3 | 2026-05-02 |
| UAL6 | United Airlines | 3 | 2026-04-30 |
| UAL28 | United Airlines | 3 | 2026-05-09 |
| UAL27 | United Airlines | 3 | 2026-04-24 |
| UAL1855 | United Airlines | 3 | 2026-04-16 |
| UAL114 | United Airlines | 3 | 2026-05-11 |
| UAL760 | United Airlines | 2 | 2026-04-28 |
| UAL7 | United Airlines | 2 | 2026-05-02 |
| UAL62 | United Airlines | 2 | 2026-05-01 |
| UAL60 | United Airlines | 2 | 2026-05-14 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-05-30 | UAL98 | LAX → MEL | May 30, 06:20 UTC | May 30, 06:40 UTC | 20m |
| 2026-05-29 | UAL199 | PVG → LAX | May 29, 12:31 UTC | May 29, 23:44 UTC | 11h 13m |
| 2026-05-29 | UAL199 | PVG → LAX | May 29, 06:40 UTC | May 29, 23:55 UTC | 17h 15m |
| 2026-05-28 | UAL198 | LAX → PVG | May 28, 20:30 UTC | May 29, 14:40 UTC | 18h 10m |
| 2026-05-28 | UAL153 | HKG → LAX | May 28, 04:45 UTC | May 28, 17:25 UTC | 12h 40m |
| 2026-05-28 | UAL153 | HKG → LAX | May 28, 02:20 UTC | May 28, 02:40 UTC | 20m |
| 2026-05-27 | UAL152 | LAX → HKG | May 27, 13:05 UTC | May 27, 13:15 UTC | 10m |
| 2026-05-27 | UAL152 | LAX → HKG | May 27, 12:49 UTC | May 27, 14:56 UTC | 2h 7m |
| 2026-05-26 | UAL152 | LAX → HKG | May 26, 20:20 UTC | May 27, 10:35 UTC | 14h 15m |
| 2026-05-25 | UAL2403 | RDU → EWR | May 25, 16:50 UTC | May 25, 21:45 UTC | 4h 54m |
| 2026-05-24 | UAL187 | JNB → EWR | May 24, 20:20 UTC | May 25, 11:55 UTC | 15h 35m |
| 2026-05-24 | UAL188 | EWR → JNB | May 24, 01:55 UTC | May 24, 15:40 UTC | 13h 45m |
| 2026-05-23 | UAL2096 | LAX → EWR | May 23, 16:30 UTC | May 23, 21:15 UTC | 4h 45m |
| 2026-05-22 | UAL821 | SFO → MEX | May 22, 14:10 UTC | May 23, 02:55 UTC | 12h 45m |
| 2026-05-22 | UAL821 | SFO → MEX | May 22, 11:35 UTC | May 22, 11:45 UTC | 10m |
| 2026-05-22 | UAL821 | SFO → MEX | May 22, 09:20 UTC | May 22, 09:55 UTC | 35m |
| 2026-05-22 | UAL821 | SFO → MEX | May 22, 09:20 UTC | May 22, 11:34 UTC | 2h 14m |
| 2026-05-22 | UAL820 | MEX → SFO | May 22, 01:35 UTC | May 22, 02:15 UTC | 40m |
| 2026-05-22 | UAL820 | MEX → SFO | May 22, 00:00 UTC | May 22, 00:15 UTC | 15m |
| 2026-05-21 | UAL820 | MEX → SFO | May 21, 07:40 UTC | May 21, 21:35 UTC | 13h 55m |
| 2026-05-20 | UAL199 | PVG → LAX | May 20, 13:25 UTC | May 20, 14:50 UTC | 1h 25m |
| 2026-05-20 | UAL199 | PVG → LAX | May 20, 12:31 UTC | May 20, 23:18 UTC | 10h 47m |
| 2026-05-20 | UAL199 | PVG → LAX | May 20, 06:25 UTC | May 20, 23:25 UTC | 17h 0m |
| 2026-05-19 | UAL198 | LAX → PVG | May 19, 20:05 UTC | May 20, 07:55 UTC | 11h 51m |
| 2026-05-19 | UAL198 | LAX → PVG | May 19, 20:08 UTC | May 20, 09:02 UTC | 12h 54m |
| 2026-05-19 | UAL153 | HKG → LAX | May 19, 05:10 UTC | May 19, 17:40 UTC | 12h 30m |
| 2026-05-19 | UAL153 | HKG → LAX | May 19, 02:05 UTC | May 19, 02:15 UTC | 10m |
| 2026-05-18 | UAL152 | LAX → HKG | May 18, 13:54 UTC | May 18, 16:05 UTC | 2h 11m |
| 2026-05-18 | UAL152 | LAX → HKG | May 18, 14:05 UTC | May 18, 14:20 UTC | 15m |
| 2026-05-18 | UAL152 | LAX → HKG | May 18, 10:25 UTC | May 18, 10:50 UTC | 25m |
| 2026-05-17 | UAL152 | LAX → HKG | May 17, 20:35 UTC | May 18, 09:55 UTC | 13h 20m |
| 2026-05-16 | UAL2692 | IAD → PHL | May 16, 13:54 UTC | May 16, 18:40 UTC | 4h 46m |
| 2026-05-16 | UAL2692 | IAD → PHL | May 16, 13:31 UTC | May 16, 18:40 UTC | 5h 10m |
| 2026-05-15 | UAL713 | ORD → DEL | May 15, 17:45 UTC | May 15, 22:20 UTC | 4h 35m |
| 2026-05-15 | UAL61 | BRU → EWR | May 15, 01:00 UTC | May 15, 14:45 UTC | 13h 45m |
| 2026-05-14 | UAL60 | SFO → MEL | May 14, 07:01 UTC | May 14, 22:06 UTC | 15h 5m |
| 2026-05-14 | UAL60 | SFO → MEL | May 14, 07:30 UTC | May 14, 07:55 UTC | 25m |
| 2026-05-13 | UAL1757 | PIT → DEN | May 13, 22:45 UTC | May 14, 03:55 UTC | 5h 10m |
| 2026-05-13 | UAL1849 | MCO → EWR | May 13, 15:50 UTC | May 13, 20:25 UTC | 4h 35m |
| 2026-05-13 | UAL806 | ICN → SFO | May 13, 02:40 UTC | May 13, 12:45 UTC | 10h 5m |
| 2026-05-12 | UAL805 | SFO → ICN | May 12, 07:40 UTC | May 12, 18:40 UTC | 11h 0m |
| 2026-05-11 | UAL114 | PPT → SFO | May 11, 07:35 UTC | May 11, 15:05 UTC | 7h 30m |
| 2026-05-10 | UAL115 | SFO → PPT | May 10, 20:45 UTC | May 11, 04:35 UTC | 7h 50m |
| 2026-05-09 | UAL28 | SIN → SFO | May 9, 14:55 UTC | May 10, 04:04 UTC | 13h 10m |
| 2026-05-09 | UAL28 | SIN → SFO | May 9, 07:50 UTC | May 10, 04:04 UTC | 20h 15m |
| 2026-05-09 | UAL28 | SIN → SFO | May 9, 07:25 UTC | May 10, 04:04 UTC | 20h 40m |
| 2026-05-08 | UAL29 | SFO → SIN | May 8, 18:10 UTC | May 9, 15:35 UTC | 21h 25m |
| 2026-05-08 | UAL114 | PPT → SFO | May 8, 07:34 UTC | May 8, 15:15 UTC | 7h 40m |
| 2026-05-08 | UAL114 | PPT → SFO | May 8, 07:30 UTC | May 8, 15:14 UTC | 7h 44m |
| 2026-05-07 | UAL115 | SFO → PPT | May 7, 20:55 UTC | May 8, 04:49 UTC | 7h 55m |
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 N23994 page for operator, model, and routing details .