sensors Mode-S transponder
AC7A61
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N903AR · BOEING 747-400 · operated by UMB BANK NA TRUSTEE
- Hex
- AC7A61
- Octal
- 53075141
- Decimal
- 11,303,521
- Country
- US
- Tail
- N903AR
- Type
- B744
- Flights observed
- 198
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 3h ago
Last known position
Country allocation
The ICAO 24-bit address AC7A61 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 |
|---|---|---|---|
| KYE9521 | SkyLease Cargo | 49 | 2026-07-18 |
| KYE9520 | - | 39 | 2026-07-16 |
| KYE7526 | SkyLease Cargo | 15 | 2026-05-30 |
| KYE4525 | SkyLease Cargo | 14 | 2026-05-30 |
| KYE7525 | SkyLease Cargo | 13 | 2026-05-29 |
| KYE4524 | SkyLease Cargo | 13 | 2026-05-31 |
| KYE4515 | SkyLease Cargo | 12 | 2026-05-05 |
| KYE4514 | SkyLease Cargo | 10 | 2026-05-06 |
| KYE4572 | SkyLease Cargo | 4 | 2026-05-26 |
| KYE4521 | SkyLease Cargo | 4 | 2026-04-30 |
| KYE4520 | SkyLease Cargo | 4 | 2026-04-30 |
| KYE4526 | SkyLease Cargo | 3 | 2026-04-28 |
| KYE4523 | SkyLease Cargo | 3 | 2026-04-27 |
| KYE4522 | SkyLease Cargo | 3 | 2026-04-29 |
| KYE4530 | - | 2 | 2026-05-16 |
| KYE4517 | SkyLease Cargo | 2 | 2026-04-22 |
| KYE9903 | - | 1 | 2026-06-19 |
| KYE4570 | SkyLease Cargo | 1 | 2026-05-27 |
| KYE4551 | SkyLease Cargo | 1 | 2026-05-13 |
| KYE4550 | SkyLease Cargo | 1 | 2026-05-14 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-18 | KYE9521 | MIA → ANC | Jul 18, 03:20 UTC | Jul 18, 04:55 UTC | 1h 35m |
| 2026-07-17 | KYE9521 | MIA → ANC | Jul 17, 13:29 UTC | Jul 18, 01:25 UTC | 11h 55m |
| 2026-07-16 | KYE9520 | ANC → ORD | Jul 16, 20:05 UTC | Jul 17, 01:39 UTC | 5h 35m |
| 2026-07-16 | KYE9520 | - | Jul 16, 10:45 UTC | Jul 16, 18:10 UTC | 7h 25m |
| 2026-07-15 | KYE9521 | - | Jul 15, 19:20 UTC | Jul 15, 20:00 UTC | 40m |
| 2026-07-15 | KYE9521 | ORD → ICN | Jul 15, 01:00 UTC | Jul 15, 14:25 UTC | 13h 25m |
| 2026-07-14 | KYE9520 | - | Jul 14, 05:50 UTC | Jul 14, 11:15 UTC | 5h 25m |
| 2026-07-13 | KYE9520 | - | Jul 13, 20:30 UTC | Jul 14, 03:55 UTC | 7h 25m |
| 2026-07-13 | KYE9521 | - | Jul 13, 13:55 UTC | Jul 13, 14:05 UTC | 10m |
| 2026-07-13 | KYE9521 | - | Jul 13, 07:01 UTC | Jul 13, 08:30 UTC | 1h 30m |
| 2026-07-12 | KYE9521 | - | Jul 12, 22:15 UTC | Jul 13, 04:55 UTC | 6h 40m |
| 2026-07-12 | KYE9521 | - | Jul 12, 13:01 UTC | Jul 12, 18:40 UTC | 5h 40m |
| 2026-07-11 | KYE9520 | - | Jul 11, 21:10 UTC | Jul 12, 02:35 UTC | 5h 25m |
| 2026-07-11 | KYE9520 | - | Jul 11, 11:50 UTC | Jul 11, 19:25 UTC | 7h 35m |
| 2026-07-10 | KYE9521 | - | Jul 10, 23:55 UTC | Jul 11, 00:30 UTC | 35m |
| 2026-07-10 | KYE9521 | - | Jul 10, 08:25 UTC | Jul 10, 21:50 UTC | 13h 25m |
| 2026-07-09 | KYE9520 | ANC → ORD | Jul 9, 17:25 UTC | Jul 9, 22:55 UTC | 5h 30m |
| 2026-07-09 | KYE9520 | - | Jul 9, 08:05 UTC | Jul 9, 15:35 UTC | 7h 30m |
| 2026-07-08 | KYE9521 | - | Jul 8, 19:40 UTC | Jul 8, 23:10 UTC | 3h 30m |
| 2026-07-08 | KYE9521 | ORD → ICN | Jul 8, 00:35 UTC | Jul 8, 13:45 UTC | 13h 10m |
| 2026-07-07 | KYE9520 | ANC → ORD | Jul 7, 03:15 UTC | Jul 7, 08:55 UTC | 5h 40m |
| 2026-07-06 | KYE9520 | - | Jul 6, 17:55 UTC | Jul 7, 01:20 UTC | 7h 25m |
| 2026-07-06 | KYE9521 | - | Jul 6, 11:45 UTC | Jul 6, 11:55 UTC | 10m |
| 2026-07-06 | KYE9521 | - | Jul 6, 03:50 UTC | Jul 6, 08:40 UTC | 4h 50m |
| 2026-07-05 | KYE9521 | ORD → NRT | Jul 5, 13:40 UTC | Jul 6, 01:40 UTC | 12h 0m |
| 2026-07-04 | KYE9520 | ANC → ORD | Jul 4, 22:35 UTC | Jul 5, 03:55 UTC | 5h 20m |
| 2026-07-04 | KYE9520 | - | Jul 4, 07:15 UTC | Jul 4, 20:40 UTC | 13h 25m |
| 2026-07-04 | KYE9521 | - | Jul 4, 00:35 UTC | Jul 4, 04:30 UTC | 3h 55m |
| 2026-07-03 | KYE9521 | ORD → ICN | Jul 3, 09:05 UTC | Jul 3, 22:25 UTC | 13h 20m |
| 2026-07-02 | KYE9520 | ANC → ORD | Jul 2, 17:50 UTC | Jul 2, 23:40 UTC | 5h 50m |
| 2026-07-02 | KYE9520 | - | Jul 2, 02:30 UTC | Jul 2, 16:20 UTC | 13h 49m |
| 2026-07-01 | KYE9521 | - | Jul 1, 19:35 UTC | Jul 1, 23:10 UTC | 3h 35m |
| 2026-07-01 | KYE9521 | - | Jul 1, 11:50 UTC | Jul 1, 14:00 UTC | 2h 10m |
| 2026-07-01 | KYE9521 | - | Jul 1, 01:15 UTC | Jul 1, 02:55 UTC | 1h 40m |
| 2026-06-30 | KYE9520 | - | Jun 30, 00:25 UTC | Jun 30, 04:40 UTC | 4h 16m |
| 2026-06-29 | KYE9520 | - | Jun 29, 09:05 UTC | Jun 29, 22:49 UTC | 13h 45m |
| 2026-06-29 | KYE9521 | - | Jun 29, 00:34 UTC | Jun 29, 05:30 UTC | 4h 55m |
| 2026-06-28 | KYE9521 | ORD → NRT | Jun 28, 10:39 UTC | Jun 28, 22:45 UTC | 12h 5m |
| 2026-06-27 | KYE9520 | - | Jun 27, 23:50 UTC | Jun 28, 05:34 UTC | 5h 45m |
| 2026-06-27 | KYE9520 | - | Jun 27, 08:49 UTC | Jun 27, 21:40 UTC | 12h 50m |
| 2026-06-27 | KYE9521 | - | Jun 27, 01:54 UTC | Jun 27, 06:05 UTC | 4h 10m |
| 2026-06-26 | KYE9521 | - | Jun 26, 09:35 UTC | Jun 26, 23:19 UTC | 13h 45m |
| 2026-06-25 | KYE9520 | ANC → ORD | Jun 25, 23:24 UTC | Jun 26, 04:55 UTC | 5h 30m |
| 2026-06-25 | KYE9520 | - | Jun 25, 13:59 UTC | Jun 25, 21:29 UTC | 7h 30m |
| 2026-06-25 | KYE9521 | - | Jun 25, 08:04 UTC | Jun 25, 08:24 UTC | 20m |
| 2026-06-24 | KYE9521 | - | Jun 24, 23:34 UTC | Jun 25, 04:25 UTC | 4h 50m |
| 2026-06-24 | KYE9521 | - | Jun 24, 09:15 UTC | Jun 24, 21:14 UTC | 12h 0m |
| 2026-06-23 | KYE9520 | ANC → ORD | Jun 23, 20:29 UTC | Jun 24, 01:49 UTC | 5h 20m |
| 2026-06-23 | KYE9520 | - | Jun 23, 05:20 UTC | Jun 23, 19:00 UTC | 13h 40m |
| 2026-06-22 | KYE9521 | - | Jun 22, 22:24 UTC | Jun 23, 02:04 UTC | 3h 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 N903AR page for operator, model, and routing details .