sensors Mode-S transponder
AA6B9D
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N77012 · BOEING 777-200 · operated by UNITED AIRLINES INC
- Hex
- AA6B9D
- Octal
- 52465635
- Decimal
- 11,168,669
- Country
- US
- Tail
- N77012
- Type
- B772
- Flights observed
- 192
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- Jul 26, 17:45 UTC
Last known position
Country allocation
The ICAO 24-bit address AA6B9D 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 |
|---|---|---|---|
| UAL59 | - | 7 | 2026-06-29 |
| UAL2397 | United Airlines | 7 | 2026-04-17 |
| UAL2238 | United Airlines | 7 | 2026-04-16 |
| UAL804 | - | 6 | 2026-07-03 |
| UAL58 | - | 6 | 2026-06-28 |
| UAL46 | - | 6 | 2026-07-19 |
| UAL933 | United Airlines | 5 | 2026-05-26 |
| UAL803 | United Airlines | 5 | 2026-05-17 |
| UAL5 | United Airlines | 5 | 2026-07-26 |
| UAL22 | United Airlines | 5 | 2026-06-16 |
| UAL97 | - | 4 | 2026-06-23 |
| UAL927 | - | 4 | 2026-06-26 |
| UAL918 | United Airlines | 4 | 2026-05-16 |
| UAL818 | United Airlines | 4 | 2026-07-22 |
| UAL57 | United Airlines | 4 | 2026-04-18 |
| UAL4 | United Airlines | 4 | 2026-07-25 |
| UAL131 | - | 4 | 2026-06-18 |
| UAL130 | United Airlines | 4 | 2026-05-18 |
| UAL96 | - | 3 | 2026-06-22 |
| UAL943 | - | 3 | 2026-07-16 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-26 | UAL925 | LHR → IAD | Jul 26, 16:35 UTC | Jul 26, 17:45 UTC | 1h 10m |
| 2026-07-26 | UAL5 | IAH → LHR | Jul 26, 01:55 UTC | Jul 26, 10:30 UTC | 8h 36m |
| 2026-07-26 | UAL5 | IAH → LHR | Jul 26, 01:50 UTC | Jul 26, 10:30 UTC | 8h 40m |
| 2026-07-25 | UAL4 | LHR → IAH | Jul 25, 12:55 UTC | Jul 25, 22:30 UTC | 9h 35m |
| 2026-07-25 | UAL924 | IAD → LHR | Jul 25, 03:20 UTC | Jul 25, 09:45 UTC | 6h 25m |
| 2026-07-24 | UAL925 | LHR → IAD | Jul 24, 16:10 UTC | Jul 24, 23:25 UTC | 7h 15m |
| 2026-07-24 | UAL5 | IAH → LHR | Jul 24, 02:10 UTC | Jul 24, 10:55 UTC | 8h 45m |
| 2026-07-22 | UAL818 | EZE → IAH | Jul 22, 00:30 UTC | Jul 22, 05:15 UTC | 4h 45m |
| 2026-07-22 | UAL818 | EZE → IAH | Jul 22, 00:16 UTC | Jul 22, 10:12 UTC | 9h 56m |
| 2026-07-21 | UAL819 | IAH → EZE | Jul 21, 02:50 UTC | Jul 21, 11:55 UTC | 9h 5m |
| 2026-07-20 | UAL4 | LHR → IAH | Jul 20, 15:15 UTC | Jul 21, 00:25 UTC | 9h 10m |
| 2026-07-20 | UAL5 | IAH → LHR | Jul 20, 01:50 UTC | Jul 20, 11:00 UTC | 9h 10m |
| 2026-07-19 | UAL47 | - | Jul 19, 13:15 UTC | Jul 19, 23:05 UTC | 9h 50m |
| 2026-07-19 | UAL46 | IAH → FRA | Jul 19, 01:08 UTC | Jul 19, 10:48 UTC | 9h 40m |
| 2026-07-19 | UAL46 | - | Jul 19, 01:20 UTC | Jul 19, 10:45 UTC | 9h 25m |
| 2026-07-18 | UAL3940 | DEN → SEA | Jul 18, 19:00 UTC | Jul 18, 21:35 UTC | 2h 35m |
| 2026-07-16 | UAL943 | LIS → IAD | Jul 16, 11:40 UTC | Jul 16, 19:05 UTC | 7h 25m |
| 2026-07-16 | UAL942 | IAD → LIS | Jul 16, 03:00 UTC | Jul 16, 09:15 UTC | 6h 15m |
| 2026-07-14 | UAL3926 | - | Jul 14, 04:35 UTC | Jul 14, 07:10 UTC | 2h 35m |
| 2026-07-12 | UAL4 | - | Jul 12, 13:10 UTC | Jul 12, 22:35 UTC | 9h 25m |
| 2026-07-12 | UAL924 | IAD → LHR | Jul 12, 02:46 UTC | Jul 12, 10:04 UTC | 7h 18m |
| 2026-07-11 | UAL925 | LHR → IAD | Jul 11, 16:20 UTC | Jul 12, 00:01 UTC | 7h 40m |
| 2026-07-11 | UAL5 | - | Jul 11, 01:55 UTC | Jul 11, 10:20 UTC | 8h 25m |
| 2026-07-10 | UAL47 | - | Jul 10, 12:25 UTC | Jul 10, 22:45 UTC | 10h 20m |
| 2026-07-09 | UAL46 | - | Jul 9, 23:45 UTC | Jul 10, 08:50 UTC | 9h 5m |
| 2026-07-09 | UAL879 | - | Jul 9, 09:20 UTC | Jul 9, 18:50 UTC | 9h 30m |
| 2026-07-08 | UAL880 | - | Jul 8, 22:20 UTC | Jul 9, 07:15 UTC | 8h 55m |
| 2026-07-08 | UAL818 | - | Jul 8, 08:10 UTC | Jul 8, 09:55 UTC | 1h 45m |
| 2026-07-08 | UAL818 | - | Jul 8, 00:05 UTC | Jul 8, 08:00 UTC | 7h 55m |
| 2026-07-07 | UAL819 | - | Jul 7, 06:50 UTC | Jul 7, 11:15 UTC | 4h 25m |
| 2026-07-07 | UAL819 | - | Jul 7, 02:00 UTC | Jul 7, 04:20 UTC | 2h 20m |
| 2026-07-06 | UAL47 | FRA → IAH | Jul 6, 12:30 UTC | Jul 6, 23:05 UTC | 10h 35m |
| 2026-07-06 | UAL46 | - | Jul 6, 00:05 UTC | Jul 6, 09:20 UTC | 9h 15m |
| 2026-07-04 | UAL4 | - | Jul 4, 12:55 UTC | Jul 4, 22:45 UTC | 9h 50m |
| 2026-07-04 | UAL924 | IAD → LHR | Jul 4, 03:40 UTC | Jul 4, 10:15 UTC | 6h 35m |
| 2026-07-03 | UAL804 | HND → IAD | Jul 3, 07:40 UTC | Jul 3, 19:50 UTC | 12h 10m |
| 2026-07-02 | UAL875 | - | Jul 2, 18:20 UTC | Jul 3, 04:40 UTC | 10h 20m |
| 2026-06-30 | UAL673 | BCN → SFO | Jun 30, 15:01 UTC | Jul 1, 02:24 UTC | 11h 23m |
| 2026-06-30 | UAL673 | - | Jun 30, 15:00 UTC | Jul 1, 02:40 UTC | 11h 40m |
| 2026-06-30 | UAL672 | SFO → BCN | Jun 30, 01:55 UTC | Jun 30, 12:45 UTC | 10h 50m |
| 2026-06-29 | UAL59 | - | Jun 29, 11:20 UTC | Jun 29, 13:09 UTC | 1h 50m |
| 2026-06-29 | UAL59 | FRA → SFO | Jun 29, 11:14 UTC | Jun 29, 21:25 UTC | 10h 11m |
| 2026-06-29 | UAL59 | FRA → SFO | Jun 29, 11:14 UTC | Jun 29, 21:41 UTC | 10h 27m |
| 2026-06-28 | UAL58 | SFO → FRA | Jun 28, 21:22 UTC | Jun 29, 07:32 UTC | 10h 10m |
| 2026-06-28 | UAL58 | - | Jun 28, 21:24 UTC | Jun 29, 00:20 UTC | 2h 55m |
| 2026-06-28 | UAL852 | - | Jun 28, 06:55 UTC | Jun 28, 17:55 UTC | 11h 0m |
| 2026-06-27 | UAL853 | - | Jun 27, 19:49 UTC | Jun 27, 20:14 UTC | 25m |
| 2026-06-27 | UAL853 | - | Jun 27, 07:30 UTC | Jun 27, 08:05 UTC | 35m |
| 2026-06-26 | UAL927 | - | Jun 26, 16:00 UTC | Jun 26, 17:40 UTC | 1h 40m |
| 2026-06-26 | UAL927 | FRA → SFO | Jun 26, 15:51 UTC | Jun 27, 02:34 UTC | 10h 43m |
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 N77012 page for operator, model, and routing details .