sensors Mode-S transponder
A4C9F8
ICAO 24-bit transponder address · allocated to United States
Currently assigned to N4077J · AIRBUS A-321neo · operated by JETBLUE AIRWAYS CORP
- Hex
- A4C9F8
- Octal
- 51144770
- Decimal
- 10,799,608
- Country
- US
- Tail
- N4077J
- Type
- A21N
- Flights observed
- 123
- Distinct callsigns
- 20
- Country
- US
- Last broadcast
- 28m ago
Last known position
Country allocation
The ICAO 24-bit address A4C9F8 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 | JetBlue Airways | 9 | 2026-05-20 |
| JBU20 | JetBlue Airways | 9 | 2026-05-27 |
| JBU1620 | JetBlue Airways | 9 | 2026-05-09 |
| JBU7 | JetBlue Airways | 8 | 2026-05-27 |
| JBU346 | JetBlue Airways | 8 | 2026-05-13 |
| JBU345 | JetBlue Airways | 6 | 2026-05-13 |
| JBU33 | JetBlue Airways | 6 | 2026-05-26 |
| JBU323 | JetBlue Airways | 6 | 2026-04-15 |
| JBU31 | JetBlue Airways | 6 | 2026-05-20 |
| JBU2261 | JetBlue Airways | 6 | 2026-05-25 |
| JBU2260 | JetBlue Airways | 6 | 2026-05-25 |
| JBU2124 | JetBlue Airways | 6 | 2026-04-16 |
| JBU1408 | JetBlue Airways | 6 | 2026-05-26 |
| JBU1107 | JetBlue Airways | 6 | 2026-05-28 |
| JBU2220 | JetBlue Airways | 4 | 2026-05-29 |
| JBU1621 | JetBlue Airways | 4 | 2026-05-10 |
| JBU34 | JetBlue Airways | 3 | 2026-05-07 |
| JBU1407 | JetBlue Airways | 3 | 2026-05-24 |
| JBU1079 | JetBlue Airways | 3 | 2026-05-23 |
| JBU72 | JetBlue Airways | 2 | 2026-05-23 |
Recent flights last 50
| Date | Flight | Route | Takeoff | Landing | Duration |
|---|---|---|---|---|---|
| 2026-05-30 | JBU841 | JFK → SAV | May 30, 01:30 UTC | May 30, 07:45 UTC | 6h 15m |
| 2026-05-29 | JBU2220 | LHR → JFK | May 29, 07:30 UTC | May 29, 14:40 UTC | 7h 10m |
| 2026-05-28 | JBU1107 | JFK → LHR | May 28, 13:05 UTC | May 28, 19:40 UTC | 6h 35m |
| 2026-05-28 | JBU1107 | JFK → LHR | May 28, 13:05 UTC | May 29, 08:50 UTC | 19h 45m |
| 2026-05-27 | JBU20 | LHR → JFK | May 27, 11:55 UTC | May 27, 19:10 UTC | 7h 15m |
| 2026-05-27 | JBU7 | JFK → LHR | May 27, 01:24 UTC | May 27, 08:25 UTC | 7h 1m |
| 2026-05-26 | JBU1408 | MIA → EWR | May 26, 11:00 UTC | May 26, 12:24 UTC | 1h 25m |
| 2026-05-26 | JBU1408 | MIA → EWR | May 26, 10:58 UTC | May 27, 08:25 UTC | 21h 28m |
| 2026-05-26 | JBU33 | BOS → SFO | May 26, 01:30 UTC | May 26, 08:04 UTC | 6h 35m |
| 2026-05-25 | JBU2260 | MAD → BOS | May 25, 12:42 UTC | May 26, 12:00 UTC | 23h 18m |
| 2026-05-25 | JBU2261 | LGA → PBI | May 25, 03:20 UTC | May 25, 10:10 UTC | 6h 50m |
| 2026-05-25 | JBU2261 | LGA → PBI | May 25, 03:18 UTC | May 26, 02:00 UTC | 22h 42m |
| 2026-05-24 | JBU1407 | JFK → CDG | May 24, 00:00 UTC | May 24, 17:20 UTC | 17h 20m |
| 2026-05-23 | JBU72 | SLC → JFK | May 23, 11:34 UTC | May 24, 10:00 UTC | 22h 26m |
| 2026-05-23 | JBU72 | SLC → JFK | May 23, 11:35 UTC | May 23, 18:55 UTC | 7h 20m |
| 2026-05-23 | JBU1079 | JFK → MBJ | May 23, 03:00 UTC | May 23, 08:40 UTC | 5h 40m |
| 2026-05-22 | JBU834 | SFO → BOS | May 22, 19:25 UTC | May 23, 00:25 UTC | 5h 0m |
| 2026-05-22 | JBU1333 | BOS → SFO | May 22, 11:20 UTC | May 22, 17:50 UTC | 6h 31m |
| 2026-05-20 | JBU32 | AMS → BOS | May 20, 09:45 UTC | May 20, 10:00 UTC | 15m |
| 2026-05-20 | JBU32 | AMS → BOS | May 20, 09:45 UTC | May 20, 17:45 UTC | 8h 1m |
| 2026-05-20 | JBU31 | BOS → AMS | May 20, 01:20 UTC | May 20, 07:55 UTC | 6h 36m |
| 2026-05-19 | JBU2260 | MAD → BOS | May 19, 17:40 UTC | May 19, 19:20 UTC | 1h 40m |
| 2026-05-19 | JBU2260 | MAD → BOS | May 19, 11:50 UTC | May 19, 13:10 UTC | 1h 20m |
| 2026-05-19 | JBU2261 | LGA → PBI | May 19, 02:50 UTC | May 19, 09:40 UTC | 6h 50m |
| 2026-05-18 | JBU2220 | LHR → JFK | May 18, 07:30 UTC | May 18, 14:40 UTC | 7h 10m |
| 2026-05-18 | JBU2220 | LHR → JFK | May 18, 07:29 UTC | May 19, 04:15 UTC | 20h 46m |
| 2026-05-17 | JBU1107 | JFK → LHR | May 17, 13:10 UTC | May 17, 19:25 UTC | 6h 15m |
| 2026-05-16 | JBU20 | LHR → JFK | May 16, 19:10 UTC | May 17, 03:05 UTC | 7h 55m |
| 2026-05-16 | JBU20 | LHR → JFK | May 16, 19:08 UTC | May 17, 14:45 UTC | 19h 38m |
| 2026-05-16 | JBU7 | JFK → LHR | May 16, 02:26 UTC | May 17, 02:00 UTC | 23h 35m |
| 2026-05-15 | JBU1408 | MIA → EWR | May 15, 10:50 UTC | May 15, 12:00 UTC | 1h 10m |
| 2026-05-15 | JBU1408 | MIA → EWR | May 15, 10:45 UTC | May 16, 09:01 UTC | 22h 16m |
| 2026-05-15 | JBU1408 | MIA → EWR | May 15, 10:45 UTC | May 16, 09:01 UTC | 22h 16m |
| 2026-05-15 | JBU33 | BOS → SFO | May 15, 01:45 UTC | May 15, 08:10 UTC | 6h 25m |
| 2026-05-14 | JBU331 | BDL → MCO | May 14, 00:09 UTC | May 14, 20:50 UTC | 20h 42m |
| 2026-05-13 | JBU346 | SRQ → JFK | May 13, 11:40 UTC | May 13, 13:15 UTC | 1h 35m |
| 2026-05-13 | JBU346 | SRQ → JFK | May 13, 11:38 UTC | May 14, 10:00 UTC | 22h 23m |
| 2026-05-13 | JBU345 | JFK → SRQ | May 13, 00:20 UTC | May 13, 07:30 UTC | 7h 10m |
| 2026-05-12 | JBU32 | AMS → BOS | May 12, 09:35 UTC | May 12, 17:35 UTC | 8h 0m |
| 2026-05-12 | JBU31 | BOS → AMS | May 12, 05:05 UTC | May 12, 06:40 UTC | 1h 35m |
| 2026-05-11 | JBU2260 | MAD → BOS | May 11, 13:45 UTC | May 11, 20:55 UTC | 7h 11m |
| 2026-05-11 | JBU2261 | LGA → PBI | May 11, 04:30 UTC | May 11, 11:30 UTC | 7h 0m |
| 2026-05-10 | JBU1621 | LHR → BOS | May 10, 08:00 UTC | May 10, 14:54 UTC | 6h 55m |
| 2026-05-09 | JBU1620 | BOS → LHR | May 9, 23:25 UTC | May 10, 05:55 UTC | 6h 30m |
| 2026-05-09 | JBU346 | SRQ → JFK | May 9, 11:25 UTC | May 9, 19:40 UTC | 8h 15m |
| 2026-05-09 | JBU345 | JFK → SRQ | May 9, 00:25 UTC | May 9, 07:45 UTC | 7h 20m |
| 2026-05-08 | JBU2261 | LGA → PBI | May 8, 02:45 UTC | May 9, 01:25 UTC | 22h 40m |
| 2026-05-07 | JBU34 | SFO → BOS | May 7, 10:12 UTC | May 8, 09:49 UTC | 23h 38m |
| 2026-05-07 | JBU1407 | JFK → CDG | May 7, 00:25 UTC | May 7, 18:05 UTC | 17h 40m |
| 2026-05-06 | JBU20 | LHR → JFK | May 6, 11:20 UTC | May 6, 18:55 UTC | 7h 34m |
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 N4077J page for operator, model, and routing details .