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
- 281
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 47m ago
Last known 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 |
|---|---|---|---|
| JBU855 | JetBlue Airways | 5 | 2026-06-12 |
| JBU2468 | - | 5 | 2026-06-19 |
| JBU2321 | - | 5 | 2026-07-10 |
| JBU896 | JetBlue Airways | 4 | 2026-06-10 |
| JBU811 | JetBlue Airways | 4 | 2026-05-01 |
| JBU715 | JetBlue Airways | 4 | 2026-05-19 |
| JBU266 | - | 4 | 2026-07-02 |
| JBU1855 | JetBlue Airways | 4 | 2026-04-28 |
| JBU1355 | JetBlue Airways | 4 | 2026-06-07 |
| JBU1303 | JetBlue Airways | 4 | 2026-04-15 |
| JBU818 | - | 3 | 2026-07-09 |
| 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 |
| JBU2768 | - | 3 | 2026-07-09 |
| JBU2625 | JetBlue Airways | 3 | 2026-06-01 |
| JBU2602 | - | 3 | 2026-06-16 |
| JBU2367 | JetBlue Airways | 3 | 2026-04-27 |
| JBU2006 | JetBlue Airways | 3 | 2026-04-17 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-14 | JBU97 | - | Jul 14, 01:20 UTC | Jul 14, 04:15 UTC | 2h 55m |
| 2026-07-13 | JBU1498 | DEN → JFK | Jul 13, 20:25 UTC | Jul 14, 00:00 UTC | 3h 35m |
| 2026-07-13 | JBU1497 | JFK → DEN | Jul 13, 14:40 UTC | Jul 13, 18:05 UTC | 3h 25m |
| 2026-07-12 | JBU341 | JFK → SAV | Jul 12, 21:11 UTC | Jul 13, 20:15 UTC | 23h 5m |
| 2026-07-12 | JBU341 | - | Jul 12, 21:15 UTC | Jul 12, 22:15 UTC | 1h 0m |
| 2026-07-11 | JBU2291 | JFK → ACK | Jul 11, 18:27 UTC | Jul 12, 11:25 UTC | 16h 59m |
| 2026-07-11 | JBU2291 | - | Jul 11, 18:30 UTC | Jul 11, 19:00 UTC | 30m |
| 2026-07-11 | JBU142 | SAV → JFK | Jul 11, 15:25 UTC | Jul 11, 17:00 UTC | 1h 35m |
| 2026-07-11 | JBU249 | BOS → SAV | Jul 11, 11:50 UTC | Jul 11, 13:50 UTC | 2h 0m |
| 2026-07-11 | JBU2322 | - | Jul 11, 00:45 UTC | Jul 11, 03:25 UTC | 2h 40m |
| 2026-07-10 | JBU2321 | - | Jul 10, 20:50 UTC | Jul 10, 23:40 UTC | 2h 50m |
| 2026-07-10 | JBU392 | TPA → BOS | Jul 10, 16:45 UTC | Jul 10, 19:25 UTC | 2h 40m |
| 2026-07-09 | JBU818 | JFK → BOS | Jul 9, 23:52 UTC | Jul 10, 21:55 UTC | 22h 4m |
| 2026-07-09 | JBU176 | MSY → JFK | Jul 9, 19:30 UTC | Jul 10, 18:15 UTC | 22h 46m |
| 2026-07-09 | JBU2769 | CLE → JFK | Jul 9, 10:30 UTC | Jul 10, 10:15 UTC | 23h 45m |
| 2026-07-09 | JBU2768 | JFK → CLE | Jul 9, 01:53 UTC | Jul 10, 00:15 UTC | 22h 23m |
| 2026-07-09 | JBU2768 | - | Jul 9, 01:55 UTC | Jul 9, 03:05 UTC | 1h 10m |
| 2026-07-08 | JBU1498 | DEN → JFK | Jul 8, 20:25 UTC | Jul 8, 23:50 UTC | 3h 25m |
| 2026-07-08 | JBU818 | JFK → BOS | Jul 8, 00:50 UTC | Jul 8, 01:30 UTC | 40m |
| 2026-07-08 | JBU818 | JFK → BOS | Jul 8, 00:49 UTC | Jul 9, 00:00 UTC | 23h 12m |
| 2026-07-07 | JBU176 | MSY → JFK | Jul 7, 17:25 UTC | Jul 7, 20:00 UTC | 2h 35m |
| 2026-07-07 | JBU75 | JFK → MSY | Jul 7, 13:20 UTC | Jul 7, 15:55 UTC | 2h 35m |
| 2026-07-07 | JBU254 | DCA → JFK | Jul 7, 10:55 UTC | Jul 7, 11:35 UTC | 40m |
| 2026-07-06 | JBU2324 | - | Jul 6, 18:00 UTC | Jul 6, 19:45 UTC | 1h 45m |
| 2026-07-05 | JBU2875 | MCO → PVD | Jul 5, 21:34 UTC | Jul 6, 19:45 UTC | 22h 11m |
| 2026-07-05 | JBU206 | BOS → PQI | Jul 5, 02:10 UTC | Jul 5, 03:05 UTC | 55m |
| 2026-07-05 | JBU206 | BOS → PQI | Jul 5, 02:10 UTC | Jul 6, 00:05 UTC | 21h 56m |
| 2026-07-04 | JBU1782 | - | Jul 4, 22:05 UTC | Jul 5, 00:40 UTC | 2h 35m |
| 2026-07-04 | JBU1781 | - | Jul 4, 18:05 UTC | Jul 4, 20:45 UTC | 2h 40m |
| 2026-07-04 | JBU1897 | BOS → ATL | Jul 4, 00:50 UTC | Jul 5, 00:15 UTC | 23h 25m |
| 2026-07-03 | JBU2033 | BOS → IAH | Jul 3, 15:27 UTC | Jul 4, 14:15 UTC | 22h 49m |
| 2026-07-03 | JBU1785 | BOS → PIT | Jul 3, 00:59 UTC | Jul 4, 00:15 UTC | 23h 16m |
| 2026-07-02 | JBU266 | RSW → BOS | Jul 2, 15:10 UTC | Jul 2, 17:55 UTC | 2h 45m |
| 2026-07-02 | JBU266 | RSW → BOS | Jul 2, 15:06 UTC | Jul 3, 14:15 UTC | 23h 10m |
| 2026-07-02 | JBU165 | - | Jul 2, 10:55 UTC | Jul 2, 13:45 UTC | 2h 50m |
| 2026-07-01 | JBU150 | - | Jul 1, 13:45 UTC | Jul 1, 14:15 UTC | 30m |
| 2026-07-01 | JBU150 | SAV → BOS | Jul 1, 13:44 UTC | Jul 2, 12:15 UTC | 22h 31m |
| 2026-07-01 | JBU741 | JFK → SAV | Jul 1, 10:45 UTC | Jul 1, 12:25 UTC | 1h 40m |
| 2026-07-01 | JBU741 | JFK → SAV | Jul 1, 10:43 UTC | Jul 2, 10:15 UTC | 23h 32m |
| 2026-06-30 | JBU1174 | - | Jun 30, 23:15 UTC | Jul 1, 01:10 UTC | 1h 55m |
| 2026-06-30 | JBU136 | PHX → JFK | Jun 30, 06:12 UTC | Jul 1, 01:20 UTC | 19h 9m |
| 2026-06-29 | JBU8390 | TPA → BOS | Jun 29, 20:40 UTC | Jun 29, 21:50 UTC | 1h 10m |
| 2026-06-29 | JBU8390 | TPA → BOS | Jun 29, 20:38 UTC | Jun 30, 20:15 UTC | 23h 38m |
| 2026-06-28 | JBU2768 | JFK → CLE | Jun 28, 03:50 UTC | Jun 28, 04:59 UTC | 1h 10m |
| 2026-06-28 | JBU520 | ATL → JFK | Jun 28, 00:30 UTC | Jun 28, 02:29 UTC | 2h 0m |
| 2026-06-27 | JBU897 | - | Jun 27, 19:19 UTC | Jun 27, 21:40 UTC | 2h 20m |
| 2026-06-27 | JBU506 | FLL → EWR | Jun 27, 02:09 UTC | Jun 28, 00:15 UTC | 22h 6m |
| 2026-06-26 | JBU507 | BOS → BNA | Jun 26, 22:41 UTC | Jun 27, 22:15 UTC | 23h 34m |
| 2026-06-26 | JBU1151 | - | Jun 26, 19:45 UTC | Jun 26, 20:04 UTC | 20m |
| 2026-06-26 | JBU1151 | ACK → BOS | Jun 26, 19:39 UTC | Jun 27, 18:15 UTC | 22h 36m |
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 .