sensors Mode-S transponder
A5CD55
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N473MC · BOEING 747-400 · operated by ATLAS AIR INC
- Hex
- A5CD55
- Octal
- 51346525
- Decimal
- 10,866,005
- Country
- US
- Tail
- N473MC
- Type
- B744
- Flights observed
- 130
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 2h ago
Last known position
Country allocation
The ICAO 24-bit address A5CD55 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 |
|---|---|---|---|
| GTI8811 | Atlas Air | 14 | 2026-05-07 |
| GTI8815 | - | 13 | 2026-07-10 |
| GTI8817 | Atlas Air | 12 | 2026-05-09 |
| GTI8816 | - | 12 | 2026-07-13 |
| GTI8812 | Atlas Air | 12 | 2026-05-07 |
| GTI8818 | Atlas Air | 9 | 2026-05-11 |
| GTI512 | - | 7 | 2026-07-08 |
| GTI654 | - | 6 | 2026-06-29 |
| GTI8520 | Atlas Air | 4 | 2026-05-19 |
| GTI8284 | - | 4 | 2026-07-01 |
| GTI8860 | Atlas Air | 3 | 2026-05-03 |
| GTI8537 | - | 3 | 2026-07-13 |
| GTI8193 | Atlas Air | 3 | 2026-05-12 |
| GTI511 | - | 3 | 2026-07-14 |
| GTI9449 | Atlas Air | 2 | 2026-05-16 |
| GTI8916 | - | 2 | 2026-06-26 |
| GTI8692 | Atlas Air | 2 | 2026-04-21 |
| GTI8516 | Atlas Air | 2 | 2026-05-15 |
| GTI8373 | Atlas Air | 2 | 2026-05-18 |
| GTI8137 | Atlas Air | 2 | 2026-05-16 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-14 | GTI511 | - | Jul 14, 07:30 UTC | Jul 14, 08:05 UTC | 35m |
| 2026-07-13 | GTI8537 | - | Jul 13, 19:30 UTC | Jul 14, 04:50 UTC | 9h 20m |
| 2026-07-13 | GTI8537 | - | Jul 13, 16:25 UTC | Jul 13, 16:50 UTC | 25m |
| 2026-07-13 | GTI8537 | - | Jul 13, 12:00 UTC | Jul 13, 12:25 UTC | 25m |
| 2026-07-13 | GTI8816 | - | Jul 13, 07:25 UTC | Jul 13, 08:25 UTC | 1h 0m |
| 2026-07-13 | GTI8816 | EDF → SUU | Jul 13, 00:55 UTC | Jul 13, 04:50 UTC | 3h 55m |
| 2026-07-12 | GTI8816 | - | Jul 12, 14:35 UTC | Jul 12, 21:25 UTC | 6h 50m |
| 2026-07-12 | GTI8816 | - | Jul 12, 13:15 UTC | Jul 12, 13:25 UTC | 10m |
| 2026-07-12 | GTI8816 | OSN → DNA | Jul 12, 06:50 UTC | Jul 12, 08:30 UTC | 1h 40m |
| 2026-07-10 | GTI8815 | HNL → OSN | Jul 10, 14:25 UTC | Jul 11, 07:15 UTC | 16h 51m |
| 2026-07-10 | GTI8815 | - | Jul 10, 06:40 UTC | Jul 10, 11:45 UTC | 5h 5m |
| 2026-07-10 | GTI8815 | LAX → SUU | Jul 10, 02:05 UTC | Jul 10, 03:05 UTC | 1h 0m |
| 2026-07-08 | GTI512 | - | Jul 8, 07:40 UTC | Jul 8, 10:50 UTC | 3h 10m |
| 2026-07-07 | GTI512 | - | Jul 7, 21:50 UTC | Jul 8, 03:45 UTC | 5h 55m |
| 2026-07-07 | GTI512 | ICN → ANC | Jul 7, 06:10 UTC | Jul 7, 19:30 UTC | 13h 20m |
| 2026-07-06 | GTI511 | - | Jul 6, 15:40 UTC | Jul 7, 04:00 UTC | 12h 20m |
| 2026-07-06 | GTI512 | - | Jul 6, 09:50 UTC | Jul 6, 13:05 UTC | 3h 15m |
| 2026-07-06 | GTI512 | - | Jul 6, 05:45 UTC | Jul 6, 05:55 UTC | 10m |
| 2026-07-05 | GTI512 | - | Jul 5, 23:05 UTC | Jul 6, 05:05 UTC | 6h 0m |
| 2026-07-05 | GTI512 | - | Jul 5, 12:30 UTC | Jul 5, 19:50 UTC | 7h 20m |
| 2026-07-01 | GTI511 | - | Jul 1, 19:25 UTC | Jul 1, 19:50 UTC | 25m |
| 2026-07-01 | GTI8284 | - | Jul 1, 00:05 UTC | Jul 1, 00:25 UTC | 20m |
| 2026-06-30 | GTI8284 | - | Jun 30, 06:30 UTC | Jun 30, 23:20 UTC | 16h 50m |
| 2026-06-29 | GTI8284 | - | Jun 29, 18:14 UTC | Jun 30, 02:55 UTC | 8h 41m |
| 2026-06-29 | GTI8284 | - | Jun 29, 12:24 UTC | Jun 29, 14:34 UTC | 2h 10m |
| 2026-06-29 | GTI654 | - | Jun 29, 05:50 UTC | Jun 29, 08:14 UTC | 2h 25m |
| 2026-06-28 | GTI654 | - | Jun 28, 21:50 UTC | Jun 29, 03:25 UTC | 5h 35m |
| 2026-06-28 | GTI654 | HKG → ANC | Jun 28, 10:10 UTC | Jun 28, 19:20 UTC | 9h 10m |
| 2026-06-27 | GTI9984 | - | Jun 27, 14:39 UTC | Jun 27, 22:55 UTC | 8h 15m |
| 2026-06-27 | CMB547 | NHD → SHJ | Jun 27, 11:09 UTC | Jun 27, 11:30 UTC | 20m |
| 2026-06-27 | CMB547 | - | Jun 27, 02:35 UTC | Jun 27, 08:25 UTC | 5h 50m |
| 2026-06-26 | GTI8916 | - | Jun 26, 14:25 UTC | Jun 26, 21:35 UTC | 7h 10m |
| 2026-06-26 | GTI8916 | - | Jun 26, 09:20 UTC | Jun 26, 10:39 UTC | 1h 20m |
| 2026-06-26 | GTI654 | ANC → ORD | Jun 26, 00:59 UTC | Jun 26, 06:19 UTC | 5h 20m |
| 2026-06-25 | GTI654 | ICN → ANC | Jun 25, 14:59 UTC | Jun 25, 22:29 UTC | 7h 30m |
| 2026-06-25 | GTI654 | HKG → ICN | Jun 25, 09:29 UTC | Jun 25, 12:30 UTC | 3h 0m |
| 2026-06-25 | GTI9011 | TPE → HKG | Jun 25, 03:24 UTC | Jun 25, 04:40 UTC | 1h 15m |
| 2026-05-19 | GTI8520 | ORD → IAH | May 19, 20:25 UTC | May 20, 08:45 UTC | 12h 21m |
| 2026-05-19 | GTI8520 | ORD → IAH | May 19, 07:10 UTC | May 19, 14:45 UTC | 7h 35m |
| 2026-05-19 | GTI8520 | ORD → IAH | May 19, 01:40 UTC | May 19, 04:55 UTC | 3h 15m |
| 2026-05-18 | GTI8520 | ORD → IAH | May 18, 17:35 UTC | May 18, 20:05 UTC | 2h 29m |
| 2026-05-18 | GTI8373 | HKG → ANC | May 18, 07:20 UTC | May 18, 14:50 UTC | 7h 30m |
| 2026-05-17 | GTI8373 | HKG → ANC | May 17, 19:35 UTC | May 18, 05:30 UTC | 9h 55m |
| 2026-05-17 | GTI8138 | DEL → HAN | May 17, 01:00 UTC | May 17, 15:35 UTC | 14h 35m |
| 2026-05-16 | GTI8137 | HKG → DEL | May 16, 19:40 UTC | May 16, 22:20 UTC | 2h 40m |
| 2026-05-16 | GTI8137 | HKG → DEL | May 16, 17:10 UTC | May 16, 17:25 UTC | 15m |
| 2026-05-16 | GTI9449 | MXP → HKG | May 16, 13:46 UTC | May 16, 14:11 UTC | 25m |
| 2026-05-16 | GTI9449 | MXP → HKG | May 16, 02:00 UTC | May 16, 06:41 UTC | 4h 41m |
| 2026-05-15 | GTI8516 | HNL → CVG | May 15, 12:25 UTC | May 15, 20:40 UTC | 8h 14m |
| 2026-05-15 | GTI8516 | HNL → CVG | May 15, 02:15 UTC | May 15, 04:55 UTC | 2h 40m |
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 N473MC page for operator, model, and routing details .