sensors Mode-S transponder
A2CB13
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N27958 · BOEING 787-9 Dreamliner · operated by UNITED AIRLINES INC
- Hex
- A2CB13
- Octal
- 50545423
- Decimal
- 10,668,819
- Country
- US
- Tail
- N27958
- Type
- B789
- Flights observed
- 178
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 1h ago
Last known position
Country allocation
The ICAO 24-bit address A2CB13 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 |
|---|---|---|---|
| UAL60 | - | 15 | 2026-07-07 |
| UAL61 | - | 14 | 2026-07-08 |
| UAL892 | United Airlines | 8 | 2026-06-12 |
| UAL2 | United Airlines | 8 | 2026-04-17 |
| UAL1 | United Airlines | 8 | 2026-05-14 |
| UAL893 | - | 6 | 2026-06-11 |
| UAL1757 | United Airlines | 6 | 2026-05-29 |
| UAL806 | United Airlines | 5 | 2026-06-03 |
| UAL713 | - | 5 | 2026-07-08 |
| UAL3964 | United Airlines | 5 | 2026-05-17 |
| UAL29 | United Airlines | 5 | 2026-05-31 |
| UAL28 | United Airlines | 5 | 2026-06-01 |
| UAL1849 | United Airlines | 5 | 2026-05-29 |
| UAL870 | - | 4 | 2026-07-04 |
| UAL805 | United Airlines | 4 | 2026-06-02 |
| UAL2480 | United Airlines | 4 | 2026-06-18 |
| UAL198 | - | 4 | 2026-06-25 |
| UAL863 | - | 3 | 2026-06-14 |
| UAL83 | United Airlines | 3 | 2026-06-30 |
| UAL821 | United Airlines | 3 | 2026-05-08 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-13 | UAL992 | - | Jul 13, 22:50 UTC | Jul 14, 04:45 UTC | 5h 55m |
| 2026-07-13 | UAL3920 | EWR → IAD | Jul 13, 19:35 UTC | Jul 13, 20:15 UTC | 40m |
| 2026-07-10 | UAL187 | - | Jul 10, 21:10 UTC | Jul 11, 11:55 UTC | 14h 45m |
| 2026-07-09 | UAL188 | - | Jul 9, 02:05 UTC | Jul 9, 16:30 UTC | 14h 25m |
| 2026-07-09 | UAL188 | EWR → JNB | Jul 9, 02:04 UTC | Jul 9, 16:25 UTC | 14h 21m |
| 2026-07-08 | UAL713 | SFO → EWR | Jul 8, 18:00 UTC | Jul 8, 22:45 UTC | 4h 45m |
| 2026-07-08 | UAL61 | MEL → SFO | Jul 8, 01:10 UTC | Jul 8, 14:10 UTC | 13h 0m |
| 2026-07-07 | UAL60 | SFO → MEL | Jul 7, 07:40 UTC | Jul 7, 22:20 UTC | 14h 40m |
| 2026-07-07 | UAL60 | SFO → MEL | Jul 7, 07:10 UTC | Jul 7, 22:18 UTC | 15h 8m |
| 2026-07-06 | UAL1227 | EWR → SFO | Jul 6, 17:50 UTC | Jul 6, 23:20 UTC | 5h 30m |
| 2026-07-06 | UAL123 | - | Jul 6, 06:50 UTC | Jul 6, 13:55 UTC | 7h 5m |
| 2026-07-06 | UAL123 | LHR → EWR | Jul 6, 07:02 UTC | Jul 6, 13:52 UTC | 6h 50m |
| 2026-07-05 | UAL122 | EWR → LHR | Jul 5, 14:10 UTC | Jul 5, 20:05 UTC | 5h 55m |
| 2026-07-04 | UAL713 | SFO → EWR | Jul 4, 17:54 UTC | Jul 4, 23:12 UTC | 5h 18m |
| 2026-07-04 | UAL713 | SFO → EWR | Jul 4, 17:55 UTC | Jul 4, 22:50 UTC | 4h 55m |
| 2026-07-04 | UAL870 | SYD → SFO | Jul 4, 00:55 UTC | Jul 4, 13:50 UTC | 12h 55m |
| 2026-07-04 | UAL870 | - | Jul 4, 00:50 UTC | Jul 4, 13:45 UTC | 12h 55m |
| 2026-07-03 | UAL839 | - | Jul 3, 06:55 UTC | Jul 3, 21:50 UTC | 14h 55m |
| 2026-07-02 | UAL935 | - | Jul 2, 12:30 UTC | Jul 2, 23:00 UTC | 10h 30m |
| 2026-07-01 | UAL923 | - | Jul 1, 23:25 UTC | Jul 2, 08:45 UTC | 9h 20m |
| 2026-07-01 | UAL2692 | - | Jul 1, 14:00 UTC | Jul 1, 18:50 UTC | 4h 50m |
| 2026-06-30 | UAL83 | DEL → EWR | Jun 30, 18:45 UTC | Jul 1, 02:45 UTC | 8h 0m |
| 2026-06-30 | UAL83 | DEL → EWR | Jun 30, 18:32 UTC | Jul 1, 10:09 UTC | 15h 37m |
| 2026-06-30 | UAL82 | - | Jun 30, 02:00 UTC | Jun 30, 15:30 UTC | 13h 30m |
| 2026-06-28 | UAL187 | - | Jun 28, 20:04 UTC | Jun 29, 11:20 UTC | 15h 15m |
| 2026-06-28 | UAL187 | JNB → EWR | Jun 28, 20:19 UTC | Jun 29, 11:13 UTC | 14h 54m |
| 2026-06-28 | UAL188 | EWR → JNB | Jun 28, 01:44 UTC | Jun 28, 15:34 UTC | 13h 50m |
| 2026-06-27 | UAL2096 | LAX → EWR | Jun 27, 16:10 UTC | Jun 27, 20:29 UTC | 4h 20m |
| 2026-06-26 | UAL842 | - | Jun 26, 23:55 UTC | Jun 27, 13:00 UTC | 13h 5m |
| 2026-06-26 | UAL839 | - | Jun 26, 06:29 UTC | Jun 26, 20:55 UTC | 14h 25m |
| 2026-06-25 | UAL199 | PVG → LAX | Jun 25, 07:00 UTC | Jun 25, 23:14 UTC | 16h 15m |
| 2026-06-25 | UAL198 | - | Jun 25, 00:49 UTC | Jun 25, 23:14 UTC | 22h 25m |
| 2026-06-24 | UAL198 | - | Jun 24, 22:49 UTC | Jun 25, 22:45 UTC | 23h 55m |
| 2026-06-24 | UAL198 | - | Jun 24, 20:49 UTC | Jun 25, 14:50 UTC | 18h 0m |
| 2026-06-24 | UAL198 | - | Jun 24, 20:44 UTC | Jun 25, 14:50 UTC | 18h 5m |
| 2026-06-24 | UAL33 | - | Jun 24, 08:20 UTC | Jun 24, 17:50 UTC | 9h 30m |
| 2026-06-23 | UAL7 | - | Jun 23, 15:55 UTC | Jun 24, 04:39 UTC | 12h 45m |
| 2026-06-23 | UAL7 | IAH → NRT | Jun 23, 16:02 UTC | Jun 24, 04:35 UTC | 12h 33m |
| 2026-06-23 | UAL63 | - | Jun 23, 01:25 UTC | Jun 23, 10:39 UTC | 9h 15m |
| 2026-06-22 | UAL62 | - | Jun 22, 00:04 UTC | Jun 22, 09:45 UTC | 9h 40m |
| 2026-06-22 | UAL62 | IAH → GRU | Jun 22, 00:03 UTC | Jun 22, 09:32 UTC | 9h 29m |
| 2026-06-21 | UAL6 | - | Jun 21, 08:15 UTC | Jun 21, 19:34 UTC | 11h 20m |
| 2026-06-20 | UAL32 | - | Jun 20, 18:24 UTC | Jun 21, 04:49 UTC | 10h 25m |
| 2026-06-19 | UAL2403 | EWR → LAX | Jun 19, 16:22 UTC | Jun 19, 21:32 UTC | 5h 10m |
| 2026-06-19 | UAL2403 | - | Jun 19, 16:19 UTC | Jun 19, 21:39 UTC | 5h 20m |
| 2026-06-18 | UAL2480 | BOS → SFO | Jun 18, 21:35 UTC | Jun 19, 01:54 UTC | 4h 19m |
| 2026-06-18 | UAL1593 | EWR → SFO | Jun 18, 14:10 UTC | Jun 18, 19:40 UTC | 5h 30m |
| 2026-06-17 | UAL2480 | BOS → SFO | Jun 17, 21:15 UTC | Jun 18, 01:50 UTC | 4h 35m |
| 2026-06-17 | UAL2480 | BOS → SFO | Jun 17, 21:22 UTC | Jun 18, 01:43 UTC | 4h 21m |
| 2026-06-17 | UAL1593 | LGA → DEN | Jun 17, 13:30 UTC | Jun 17, 18:50 UTC | 5h 20m |
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 N27958 page for operator, model, and routing details .