sensors Mode-S transponder
A38439
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N3257J · operated by JETBLUE AIRWAYS CORP
- Hex
- A38439
- Octal
- 50702071
- Decimal
- 10,716,217
- Country
- US
- Tail
- N3257J
- Type
- BCS3
- Flights observed
- 146
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 3h ago
Current position
Country allocation
The ICAO 24-bit address A38439 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 |
|---|---|---|---|
| JBU811 | JetBlue Airways | 4 | 2026-05-01 |
| JBU715 | JetBlue Airways | 4 | 2026-05-19 |
| JBU2468 | JetBlue Airways | 4 | 2026-05-14 |
| JBU2321 | - | 4 | 2026-04-16 |
| JBU1855 | JetBlue Airways | 4 | 2026-04-28 |
| JBU1303 | JetBlue Airways | 4 | 2026-04-15 |
| JBU896 | JetBlue Airways | 3 | 2026-05-17 |
| JBU641 | JetBlue Airways | 3 | 2026-05-14 |
| JBU502 | JetBlue Airways | 3 | 2026-04-16 |
| JBU401 | - | 3 | 2026-04-13 |
| JBU400 | JetBlue Airways | 3 | 2026-04-13 |
| JBU2367 | JetBlue Airways | 3 | 2026-04-27 |
| JBU2006 | JetBlue Airways | 3 | 2026-04-17 |
| JBU1109 | - | 3 | 2026-04-17 |
| JBU940 | JetBlue Airways | 2 | 2026-05-08 |
| JBU822 | JetBlue Airways | 2 | 2026-04-16 |
| JBU640 | JetBlue Airways | 2 | 2026-04-20 |
| JBU541 | JetBlue Airways | 2 | 2026-04-18 |
| JBU2823 | JetBlue Airways | 2 | 2026-05-20 |
| JBU267 | - | 2 | 2026-04-13 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-05-29 | JBU485 | ROC → JFK | May 29, 14:55 UTC | May 29, 21:15 UTC | 6h 21m |
| 2026-05-29 | JBU186 | SAN → JFK | May 29, 12:50 UTC | May 29, 13:40 UTC | 50m |
| 2026-05-29 | JBU186 | SAN → JFK | May 29, 12:45 UTC | May 29, 21:15 UTC | 8h 31m |
| 2026-05-21 | JBU163 | JFK → SRQ | May 21, 12:03 UTC | May 22, 04:10 UTC | 16h 8m |
| 2026-05-21 | JBU1902 | FLL → JFK | May 21, 02:45 UTC | May 21, 05:05 UTC | 2h 20m |
| 2026-05-21 | JBU1902 | FLL → JFK | May 21, 02:44 UTC | May 22, 02:15 UTC | 23h 32m |
| 2026-05-20 | JBU2823 | BOS → STI | May 20, 01:10 UTC | May 20, 02:50 UTC | 1h 40m |
| 2026-05-20 | JBU2823 | BOS → STI | May 20, 01:09 UTC | May 20, 13:40 UTC | 12h 32m |
| 2026-05-19 | JBU2374 | PUJ → FLL | May 19, 15:25 UTC | May 19, 20:55 UTC | 5h 30m |
| 2026-05-19 | JBU715 | BOS → BUF | May 19, 01:25 UTC | May 19, 02:30 UTC | 1h 5m |
| 2026-05-19 | JBU715 | BOS → BUF | May 19, 01:24 UTC | May 19, 20:55 UTC | 19h 31m |
| 2026-05-18 | JBU2754 | DCA → BOS | May 18, 22:50 UTC | May 19, 00:00 UTC | 1h 10m |
| 2026-05-18 | JBU2324 | MCO → DCA | May 18, 19:50 UTC | May 18, 21:40 UTC | 1h 50m |
| 2026-05-18 | JBU1923 | DCA → MCO | May 18, 16:25 UTC | May 18, 18:10 UTC | 1h 45m |
| 2026-05-18 | JBU2024 | MCO → DCA | May 18, 13:00 UTC | May 18, 14:50 UTC | 1h 50m |
| 2026-05-17 | JBU1355 | BOS → DCA | May 17, 19:32 UTC | May 18, 18:15 UTC | 22h 44m |
| 2026-05-17 | JBU896 | ATL → BOS | May 17, 16:02 UTC | May 18, 14:15 UTC | 22h 14m |
| 2026-05-17 | JBU896 | ATL → BOS | May 17, 16:05 UTC | May 17, 18:15 UTC | 2h 10m |
| 2026-05-17 | JBU519 | JFK → ATL | May 17, 12:35 UTC | May 17, 14:25 UTC | 1h 50m |
| 2026-05-15 | JBU2901 | JFK → FLL | May 15, 14:59 UTC | May 16, 11:55 UTC | 20h 57m |
| 2026-05-15 | JBU117 | BOS → ATL | May 15, 09:33 UTC | May 16, 01:20 UTC | 15h 47m |
| 2026-05-14 | JBU641 | BOS → CLE | May 14, 13:41 UTC | May 15, 12:15 UTC | 22h 35m |
| 2026-05-14 | JBU641 | BOS → CLE | May 14, 13:40 UTC | May 14, 15:10 UTC | 1h 30m |
| 2026-05-14 | JBU2468 | CHS → BOS | May 14, 10:05 UTC | May 14, 12:00 UTC | 1h 55m |
| 2026-05-13 | JBU1310 | JAX → BOS | May 13, 13:48 UTC | May 14, 12:10 UTC | 22h 23m |
| 2026-05-13 | JBU109 | BOS → JAX | May 13, 10:19 UTC | May 14, 10:15 UTC | 23h 57m |
| 2026-05-12 | JBU1484 | RDU → BOS | May 12, 23:35 UTC | May 13, 01:00 UTC | 1h 25m |
| 2026-05-12 | JBU1484 | RDU → BOS | May 12, 23:32 UTC | May 13, 19:35 UTC | 20h 4m |
| 2026-05-12 | JBU2783 | BOS → RDU | May 12, 20:25 UTC | May 12, 21:55 UTC | 1h 30m |
| 2026-05-12 | JBU418 | JFK → BOS | May 12, 17:25 UTC | May 12, 18:05 UTC | 40m |
| 2026-05-12 | JBU174 | PUJ → FLL | May 12, 13:55 UTC | May 12, 15:45 UTC | 1h 50m |
| 2026-05-12 | JBU173 | FLL → PUJ | May 12, 10:40 UTC | May 12, 12:35 UTC | 1h 55m |
| 2026-05-10 | JBU71 | JFK → SLC | May 10, 23:59 UTC | May 11, 14:05 UTC | 14h 6m |
| 2026-05-10 | JBU156 | PLS → JFK | May 10, 21:04 UTC | May 10, 21:54 UTC | 50m |
| 2026-05-10 | JBU156 | PLS → JFK | May 10, 18:43 UTC | May 11, 14:05 UTC | 19h 22m |
| 2026-05-10 | JBU255 | JFK → PLS | May 10, 14:09 UTC | May 10, 16:14 UTC | 2h 5m |
| 2026-05-09 | JBU2784 | BZE → JFK | May 9, 18:00 UTC | May 9, 20:10 UTC | 2h 10m |
| 2026-05-09 | JBU883 | JFK → MCO | May 9, 14:00 UTC | May 9, 16:25 UTC | 2h 25m |
| 2026-05-08 | JBU1154 | PBI → JFK | May 8, 22:25 UTC | May 9, 00:55 UTC | 2h 30m |
| 2026-05-08 | JBU53 | JFK → PBI | May 8, 18:20 UTC | May 8, 20:45 UTC | 2h 25m |
| 2026-05-08 | JBU417 | JFK → MSP | May 8, 15:45 UTC | May 8, 16:30 UTC | 45m |
| 2026-05-08 | JBU940 | LGA → JAX | May 8, 13:10 UTC | May 8, 14:25 UTC | 1h 15m |
| 2026-05-07 | JBU1290 | ILM → BOS | May 7, 19:57 UTC | May 8, 18:15 UTC | 22h 18m |
| 2026-05-07 | JBU1419 | BOS → JAX | May 7, 02:13 UTC | May 8, 00:14 UTC | 22h 2m |
| 2026-05-06 | JBU217 | JFK → LGB | May 6, 11:43 UTC | May 7, 10:15 UTC | 22h 32m |
| 2026-05-05 | JBU1500 | DAB → BOS | May 5, 21:57 UTC | May 6, 17:00 UTC | 19h 4m |
| 2026-05-05 | JBU1499 | BOS → DAB | May 5, 17:20 UTC | May 6, 16:00 UTC | 22h 41m |
| 2026-05-04 | JBU1782 | VPS → BOS | May 4, 21:10 UTC | May 5, 19:50 UTC | 22h 41m |
| 2026-05-04 | JBU1781 | BOS → MCO | May 4, 16:55 UTC | May 4, 19:35 UTC | 2h 41m |
| 2026-05-04 | JBU1781 | BOS → MCO | May 4, 16:51 UTC | May 5, 15:55 UTC | 23h 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 N3257J page for operator, model, and routing details .