sensors Mode-S transponder
A4C9D5
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N4076J · AIRBUS A-321neo · operated by JETBLUE AIRWAYS CORP
- Hex
- A4C9D5
- Octal
- 51144725
- Decimal
- 10,799,573
- Country
- US
- Tail
- N4076J
- Type
- A21N
- Flights observed
- 236
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- Jul 26, 19:25 UTC
Last known position
Country allocation
The ICAO 24-bit address A4C9D5 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 |
|---|---|---|---|
| JBU32 | - | 23 | 2026-07-16 |
| JBU31 | - | 23 | 2026-07-16 |
| JBU1408 | JetBlue Airways | 15 | 2026-07-25 |
| JBU1407 | - | 15 | 2026-07-22 |
| JBU33 | JetBlue Airways | 14 | 2026-07-25 |
| JBU1107 | - | 14 | 2026-07-20 |
| JBU346 | - | 13 | 2026-07-04 |
| JBU345 | - | 12 | 2026-07-04 |
| JBU2261 | JetBlue Airways | 12 | 2026-07-23 |
| JBU2220 | - | 12 | 2026-07-21 |
| JBU1621 | JetBlue Airways | 12 | 2026-07-24 |
| JBU7 | JetBlue Airways | 10 | 2026-07-26 |
| JBU34 | JetBlue Airways | 10 | 2026-06-12 |
| JBU20 | JetBlue Airways | 10 | 2026-07-19 |
| JBU331 | - | 9 | 2026-07-13 |
| JBU1620 | JetBlue Airways | 9 | 2026-07-23 |
| JBU2260 | JetBlue Airways | 8 | 2026-07-23 |
| JBU332 | - | 5 | 2026-07-07 |
| JBU523 | JetBlue Airways | 2 | 2026-05-07 |
| JBU2223 | JetBlue Airways | 2 | 2026-04-18 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-07-26 | JBU7 | JFK → LHR | Jul 26, 01:34 UTC | Jul 26, 19:25 UTC | 17h 52m |
| 2026-07-25 | JBU1408 | MIA → EWR | Jul 25, 10:51 UTC | Jul 26, 08:05 UTC | 21h 15m |
| 2026-07-25 | JBU33 | BOS → SFO | Jul 25, 01:35 UTC | Jul 25, 18:15 UTC | 16h 40m |
| 2026-07-24 | JBU1621 | LHR → BOS | Jul 24, 08:00 UTC | Jul 24, 09:15 UTC | 1h 15m |
| 2026-07-24 | JBU1621 | LHR → BOS | Jul 24, 07:56 UTC | Jul 25, 07:15 UTC | 23h 19m |
| 2026-07-23 | JBU1620 | BOS → LHR | Jul 23, 23:45 UTC | Jul 24, 05:40 UTC | 5h 55m |
| 2026-07-23 | JBU2260 | MAD → BOS | Jul 23, 12:30 UTC | Jul 23, 19:40 UTC | 7h 10m |
| 2026-07-23 | JBU2261 | LGA → PBI | Jul 23, 03:00 UTC | Jul 23, 09:35 UTC | 6h 35m |
| 2026-07-22 | JBU1407 | - | Jul 22, 00:45 UTC | Jul 22, 02:25 UTC | 1h 40m |
| 2026-07-22 | JBU1407 | JFK → CDG | Jul 22, 00:44 UTC | Jul 22, 17:20 UTC | 16h 36m |
| 2026-07-21 | JBU2220 | - | Jul 21, 07:40 UTC | Jul 21, 14:55 UTC | 7h 15m |
| 2026-07-20 | JBU1107 | - | Jul 20, 13:15 UTC | Jul 20, 19:40 UTC | 6h 25m |
| 2026-07-19 | JBU20 | LHR → JFK | Jul 19, 13:35 UTC | Jul 20, 13:15 UTC | 23h 41m |
| 2026-07-19 | JBU20 | LHR → JFK | Jul 19, 13:35 UTC | Jul 20, 13:15 UTC | 23h 41m |
| 2026-07-18 | JBU20 | LHR → JFK | Jul 18, 20:50 UTC | Jul 18, 21:25 UTC | 35m |
| 2026-07-18 | JBU20 | LHR → JFK | Jul 18, 20:46 UTC | Jul 19, 19:15 UTC | 22h 30m |
| 2026-07-18 | JBU20 | LHR → JFK | Jul 18, 11:25 UTC | Jul 18, 19:25 UTC | 8h 0m |
| 2026-07-18 | JBU7 | JFK → LHR | Jul 18, 01:20 UTC | Jul 18, 08:05 UTC | 6h 46m |
| 2026-07-17 | JBU1408 | - | Jul 17, 10:50 UTC | Jul 17, 11:15 UTC | 25m |
| 2026-07-17 | JBU1408 | CDG → JFK | Jul 17, 10:48 UTC | Jul 18, 08:15 UTC | 21h 28m |
| 2026-07-17 | JBU33 | BOS → CDG | Jul 17, 01:45 UTC | Jul 17, 08:25 UTC | 6h 40m |
| 2026-07-16 | JBU32 | AMS → BOS | Jul 16, 09:40 UTC | Jul 16, 16:55 UTC | 7h 15m |
| 2026-07-16 | JBU31 | BOS → AMS | Jul 16, 00:50 UTC | Jul 16, 07:30 UTC | 6h 40m |
| 2026-07-15 | JBU32 | - | Jul 15, 10:00 UTC | Jul 15, 17:10 UTC | 7h 10m |
| 2026-07-15 | JBU31 | - | Jul 15, 06:35 UTC | Jul 15, 07:15 UTC | 40m |
| 2026-07-15 | JBU31 | - | Jul 15, 00:30 UTC | Jul 15, 06:30 UTC | 6h 0m |
| 2026-07-13 | JBU331 | BOS → MXP | Jul 13, 22:26 UTC | Jul 14, 16:30 UTC | 18h 5m |
| 2026-07-13 | JBU32 | - | Jul 13, 09:35 UTC | Jul 13, 16:30 UTC | 6h 55m |
| 2026-07-13 | JBU32 | AMS → BOS | Jul 13, 09:32 UTC | Jul 14, 09:15 UTC | 23h 44m |
| 2026-07-13 | JBU31 | BNH → AMS | Jul 13, 00:25 UTC | Jul 13, 07:01 UTC | 6h 35m |
| 2026-07-12 | JBU1621 | LHR → BOS | Jul 12, 07:55 UTC | Jul 12, 14:45 UTC | 6h 50m |
| 2026-07-11 | JBU1620 | - | Jul 11, 23:25 UTC | Jul 12, 05:35 UTC | 6h 10m |
| 2026-07-11 | JBU32 | - | Jul 11, 09:40 UTC | Jul 11, 17:05 UTC | 7h 25m |
| 2026-07-11 | JBU31 | BOS → AMS | Jul 11, 00:35 UTC | Jul 11, 07:05 UTC | 6h 30m |
| 2026-07-09 | JBU1620 | BOS → LHR | Jul 9, 23:09 UTC | Jul 10, 15:30 UTC | 16h 21m |
| 2026-07-09 | JBU2261 | - | Jul 9, 03:00 UTC | Jul 9, 04:25 UTC | 1h 25m |
| 2026-07-09 | JBU2261 | BOS → MAD | Jul 9, 02:57 UTC | Jul 10, 00:25 UTC | 21h 28m |
| 2026-07-08 | JBU32 | - | Jul 8, 10:50 UTC | Jul 8, 18:05 UTC | 7h 15m |
| 2026-07-08 | JBU31 | - | Jul 8, 01:10 UTC | Jul 8, 07:55 UTC | 6h 45m |
| 2026-07-07 | JBU332 | MXP → BOS | Jul 7, 08:57 UTC | Jul 8, 07:15 UTC | 22h 19m |
| 2026-07-06 | JBU331 | BDL → MCO | Jul 6, 22:30 UTC | Jul 7, 17:50 UTC | 19h 21m |
| 2026-07-06 | JBU32 | AMS → BOS | Jul 6, 10:51 UTC | Jul 7, 09:15 UTC | 22h 25m |
| 2026-07-06 | JBU32 | - | Jul 6, 10:55 UTC | Jul 6, 11:15 UTC | 20m |
| 2026-07-06 | JBU31 | - | Jul 6, 02:20 UTC | Jul 6, 08:20 UTC | 6h 0m |
| 2026-07-04 | JBU331 | BDL → MCO | Jul 4, 22:32 UTC | Jul 5, 17:05 UTC | 18h 34m |
| 2026-07-04 | JBU346 | BCN → BOS | Jul 4, 11:16 UTC | Jul 5, 09:15 UTC | 21h 59m |
| 2026-07-04 | JBU346 | - | Jul 4, 11:20 UTC | Jul 4, 13:00 UTC | 1h 40m |
| 2026-07-04 | JBU345 | - | Jul 4, 00:40 UTC | Jul 4, 07:35 UTC | 6h 55m |
| 2026-07-03 | JBU32 | AMS → BOS | Jul 3, 09:44 UTC | Jul 4, 08:15 UTC | 22h 32m |
| 2026-07-03 | JBU32 | - | Jul 3, 09:45 UTC | Jul 3, 17:15 UTC | 7h 30m |
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 N4076J page for operator, model, and routing details .