sensors Mode-S transponder
A2CB14
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N27959 · BOEING 787-9 Dreamliner · operated by UNITED AIRLINES INC
- Hex
- A2CB14
- Octal
- 50545424
- Decimal
- 10,668,820
- Country
- US
- Tail
- N27959
- Type
- B789
- Flights observed
- 178
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 22m ago
Current position
Country allocation
The ICAO 24-bit address A2CB14 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 | - | 18 | 2026-07-08 |
| UAL820 | - | 14 | 2026-07-08 |
| UAL152 | United Airlines | 8 | 2026-07-03 |
| UAL187 | - | 7 | 2026-06-20 |
| UAL863 | - | 6 | 2026-06-16 |
| UAL935 | - | 5 | 2026-06-23 |
| UAL870 | - | 5 | 2026-06-17 |
| UAL771 | - | 5 | 2026-06-28 |
| UAL188 | United Airlines | 5 | 2026-06-20 |
| UAL153 | United Airlines | 5 | 2026-07-04 |
| UAL923 | - | 4 | 2026-06-22 |
| UAL907 | United Airlines | 4 | 2026-04-16 |
| UAL906 | United Airlines | 4 | 2026-04-16 |
| UAL82 | - | 4 | 2026-06-13 |
| UAL806 | United Airlines | 4 | 2026-05-28 |
| UAL805 | United Airlines | 4 | 2026-05-27 |
| UAL62 | - | 4 | 2026-07-12 |
| UAL33 | - | 4 | 2026-07-14 |
| UAL1227 | - | 4 | 2026-06-15 |
| UAL99 | - | 3 | 2026-07-01 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-14 | UAL33 | - | Jul 14, 08:30 UTC | Jul 14, 17:00 UTC | 8h 30m |
| 2026-07-13 | UAL7 | - | Jul 13, 16:15 UTC | Jul 14, 04:55 UTC | 12h 40m |
| 2026-07-13 | UAL63 | - | Jul 13, 01:10 UTC | Jul 13, 10:50 UTC | 9h 40m |
| 2026-07-12 | UAL62 | - | Jul 12, 01:45 UTC | Jul 12, 10:15 UTC | 8h 30m |
| 2026-07-12 | UAL62 | - | Jul 12, 00:45 UTC | Jul 12, 01:00 UTC | 15m |
| 2026-07-12 | UAL62 | IAH → GRU | Jul 12, 00:48 UTC | Jul 12, 09:59 UTC | 9h 11m |
| 2026-07-11 | UAL6 | - | Jul 11, 08:40 UTC | Jul 11, 20:35 UTC | 11h 55m |
| 2026-07-10 | UAL32 | - | Jul 10, 18:20 UTC | Jul 11, 05:01 UTC | 10h 41m |
| 2026-07-08 | UAL821 | - | Jul 8, 14:20 UTC | Jul 9, 03:25 UTC | 13h 5m |
| 2026-07-08 | UAL821 | - | Jul 8, 11:00 UTC | Jul 8, 11:05 UTC | 5m |
| 2026-07-08 | UAL821 | - | Jul 8, 08:50 UTC | Jul 8, 09:20 UTC | 30m |
| 2026-07-08 | UAL820 | - | Jul 8, 01:40 UTC | Jul 8, 02:20 UTC | 40m |
| 2026-07-08 | UAL820 | - | Jul 8, 00:00 UTC | Jul 8, 00:15 UTC | 15m |
| 2026-07-07 | UAL820 | - | Jul 7, 07:30 UTC | Jul 7, 21:15 UTC | 13h 45m |
| 2026-07-06 | UAL821 | - | Jul 6, 14:15 UTC | Jul 7, 02:50 UTC | 12h 35m |
| 2026-07-06 | UAL821 | HKG → LAX | Jul 6, 14:06 UTC | Jul 7, 02:43 UTC | 12h 37m |
| 2026-07-06 | UAL821 | - | Jul 6, 11:15 UTC | Jul 6, 11:35 UTC | 20m |
| 2026-07-06 | UAL821 | - | Jul 6, 09:00 UTC | Jul 6, 09:45 UTC | 45m |
| 2026-07-06 | UAL820 | - | Jul 6, 01:35 UTC | Jul 6, 02:30 UTC | 55m |
| 2026-07-06 | UAL820 | - | Jul 6, 00:10 UTC | Jul 6, 00:20 UTC | 10m |
| 2026-07-05 | UAL820 | - | Jul 5, 08:00 UTC | Jul 5, 21:50 UTC | 13h 50m |
| 2026-07-04 | UAL153 | HKG → LAX | Jul 4, 05:08 UTC | Jul 4, 17:29 UTC | 12h 21m |
| 2026-07-04 | UAL153 | HKG → LAX | Jul 4, 04:55 UTC | Jul 4, 17:20 UTC | 12h 25m |
| 2026-07-04 | UAL153 | HKG → LAX | Jul 4, 02:05 UTC | Jul 4, 02:25 UTC | 20m |
| 2026-07-03 | UAL152 | LAX → HKG | Jul 3, 13:00 UTC | Jul 3, 13:20 UTC | 20m |
| 2026-07-02 | UAL152 | LAX → HKG | Jul 2, 20:15 UTC | Jul 2, 21:10 UTC | 55m |
| 2026-07-02 | UAL152 | LAX → HKG | Jul 2, 20:08 UTC | Jul 3, 10:09 UTC | 14h 1m |
| 2026-07-02 | UAL33 | - | Jul 2, 08:00 UTC | Jul 2, 08:30 UTC | 30m |
| 2026-07-02 | UAL33 | NRT → LAX | Jul 2, 08:05 UTC | Jul 2, 16:52 UTC | 8h 47m |
| 2026-07-02 | UAL33 | NRT → LAX | Jul 2, 08:05 UTC | Jul 2, 17:06 UTC | 9h 1m |
| 2026-07-01 | UAL32 | - | Jul 1, 18:35 UTC | Jul 2, 05:25 UTC | 10h 50m |
| 2026-07-01 | UAL99 | - | Jul 1, 00:40 UTC | Jul 1, 14:15 UTC | 13h 35m |
| 2026-06-30 | UAL98 | LAX → MEL | Jun 30, 06:50 UTC | Jun 30, 07:15 UTC | 25m |
| 2026-06-30 | UAL98 | LAX → MEL | Jun 30, 06:14 UTC | Jun 30, 22:13 UTC | 15h 59m |
| 2026-06-29 | UAL772 | PEK → LAX | Jun 29, 04:29 UTC | Jun 29, 15:54 UTC | 11h 25m |
| 2026-06-28 | UAL771 | - | Jun 28, 07:20 UTC | Jun 28, 18:59 UTC | 11h 40m |
| 2026-06-28 | UAL771 | LAX → PEK | Jun 28, 06:54 UTC | Jun 28, 20:42 UTC | 13h 48m |
| 2026-06-27 | UAL821 | - | Jun 27, 14:09 UTC | Jun 28, 03:05 UTC | 12h 55m |
| 2026-06-27 | UAL821 | - | Jun 27, 11:35 UTC | Jun 27, 11:39 UTC | 5m |
| 2026-06-27 | UAL821 | - | Jun 27, 09:00 UTC | Jun 27, 10:34 UTC | 1h 35m |
| 2026-06-27 | UAL821 | BKK → HKG | Jun 27, 09:05 UTC | Jun 27, 11:16 UTC | 2h 11m |
| 2026-06-27 | UAL820 | - | Jun 27, 02:20 UTC | Jun 27, 02:59 UTC | 40m |
| 2026-06-27 | UAL820 | - | Jun 27, 00:25 UTC | Jun 27, 00:44 UTC | 20m |
| 2026-06-26 | UAL820 | - | Jun 26, 07:20 UTC | Jun 26, 21:30 UTC | 14h 10m |
| 2026-06-25 | UAL821 | - | Jun 25, 14:55 UTC | Jun 25, 15:24 UTC | 30m |
| 2026-06-25 | UAL821 | HKG → LAX | Jun 25, 14:06 UTC | Jun 26, 02:27 UTC | 12h 21m |
| 2026-06-25 | UAL821 | - | Jun 25, 14:04 UTC | Jun 25, 14:20 UTC | 15m |
| 2026-06-25 | UAL821 | - | Jun 25, 09:14 UTC | Jun 25, 11:30 UTC | 2h 15m |
| 2026-06-25 | UAL820 | HKG → BKK | Jun 25, 00:09 UTC | Jun 25, 02:25 UTC | 2h 15m |
| 2026-06-24 | UAL820 | - | Jun 24, 07:15 UTC | Jun 24, 21:19 UTC | 14h 5m |
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 N27959 page for operator, model, and routing details .