sensors Mode-S transponder

A4FBAC

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N420AN · AIRBUS A-321neo · operated by AMERICAN AIRLINES INC

Hex
A4FBAC
Octal
51175654
Decimal
10,812,332
Country
US
Tail
N420AN
Type
A21N
Broadcasting now · callsign AAL1957 · 23,725 ft
Flights observed
207
Distinct callsigns
20
Country
US
Last broadcast
3h ago

Current position

A4FBAC is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A4FBAC 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 AAL1957 DFW → SAT May 29, 22:35 UTCMay 29, 23:00 UTC25m
2026-05-29 AAL2756 STL → LGA May 29, 19:20 UTCMay 29, 21:15 UTC1h 55m
2026-05-29 AAL2756 STL → LGA May 29, 15:40 UTCMay 29, 17:45 UTC2h 5m
2026-05-29 AAL2635 ONT → DFW May 29, 09:10 UTCMay 29, 14:25 UTC5h 15m
2026-05-29 AAL3166 STL → PHX May 29, 01:55 UTCMay 29, 07:30 UTC5h 35m
2026-05-28 AAL3164 PSP → PHX May 28, 17:45 UTCMay 28, 22:25 UTC4h 40m
2026-05-28 AAL1928 PHL → CLT May 28, 11:10 UTCMay 28, 16:15 UTC5h 5m
2026-05-28 AAL1928 PHL → CLT May 28, 11:06 UTCMay 28, 15:53 UTC4h 47m
2026-05-28 AAL1118 DFW → BNA May 28, 05:05 UTCMay 28, 09:30 UTC4h 25m
2026-05-27 AAL1528 MIA → PHL May 27, 22:15 UTCMay 28, 03:30 UTC5h 15m
2026-05-27 AAL1528 MIA → PHL May 27, 15:20 UTCMay 27, 20:05 UTC4h 45m
2026-05-27 AAL738 LGA → IAH May 27, 02:14 UTCMay 27, 07:10 UTC4h 55m
2026-05-27 AAL738 LGA → IAH May 27, 02:11 UTCMay 27, 07:14 UTC5h 3m
2026-05-26 AAL3319 FSD → IAH May 26, 19:40 UTCMay 26, 22:59 UTC3h 20m
2026-05-26 AAL500 SFO → PHL May 26, 15:29 UTCMay 26, 18:05 UTC2h 35m
2026-05-26 AAL2575 DFW → MIA May 26, 11:24 UTCMay 26, 13:54 UTC2h 30m
2026-05-25 AAL1562 CLT → CLE May 25, 23:00 UTCMay 26, 01:49 UTC2h 50m
2026-05-25 AAL1564 DFW → SAT May 25, 16:30 UTCMay 25, 20:59 UTC4h 29m
2026-05-24 AAL2655 PDX → DFW May 24, 19:45 UTCMay 24, 20:40 UTC55m
2026-05-24 AAL2655 PDX → DFW May 24, 19:42 UTCMay 24, 20:40 UTC58m
2026-05-24 AAL2655 PDX → DFW May 24, 17:40 UTCMay 24, 18:40 UTC1h 0m
2026-05-23 AAL2982 PWM → DCA May 23, 21:30 UTCMay 24, 01:50 UTC4h 20m
2026-05-23 AAL1184 SJU → ORD May 23, 16:00 UTCMay 23, 19:50 UTC3h 51m
2026-05-23 AAL818Q DFW → PHX May 23, 12:00 UTCMay 23, 14:05 UTC2h 5m
2026-05-23 AAL2742 DCA → LGA May 23, 07:25 UTCMay 23, 10:35 UTC3h 10m
2026-05-23 AAL2742 DCA → LGA May 23, 05:40 UTCMay 23, 05:55 UTC15m
2026-05-23 AAL702 DFW → SJU May 23, 03:25 UTCMay 23, 03:40 UTC15m
2026-05-22 AAL702 DFW → SJU May 22, 23:25 UTCMay 23, 02:00 UTC2h 35m
2026-05-22 AAL2219 CUN → DFW May 22, 19:00 UTCMay 22, 21:25 UTC2h 25m
2026-05-22 AAL2219 CUN → DFW May 22, 18:59 UTCMay 22, 21:23 UTC2h 24m
2026-05-22 AAL2874 DFW → CUN May 22, 15:20 UTCMay 22, 17:00 UTC1h 40m
2026-05-22 AAL2874 DFW → CUN May 22, 15:17 UTCMay 22, 17:32 UTC2h 15m
2026-05-21 AAL2102 DFW → PNS May 21, 22:40 UTCMay 21, 22:55 UTC15m
2026-05-21 AAL2102 DFW → PNS May 21, 20:35 UTCMay 21, 22:55 UTC2h 20m
2026-05-21 AAL2102 DFW → PNS May 21, 20:33 UTCMay 21, 22:25 UTC1h 52m
2026-05-21 AAL377 MIA → PAP May 21, 13:55 UTCMay 21, 19:10 UTC5h 15m
2026-05-21 AAL2701 PHX → BOS May 21, 05:25 UTCMay 21, 09:40 UTC4h 15m
2026-05-20 AAL2301 CLT → BUF May 20, 23:15 UTCMay 21, 03:50 UTC4h 35m
2026-05-20 AAL2300 PHX → PHL May 20, 16:40 UTCMay 20, 20:50 UTC4h 10m
2026-05-20 AAL684 PHX → LIH May 20, 07:40 UTCMay 20, 13:05 UTC5h 25m
2026-05-20 AAL684 PHX → LIH May 20, 07:26 UTCMay 20, 13:00 UTC5h 34m
2026-05-19 AAL697 LIH → PHX May 19, 19:26 UTCMay 20, 01:27 UTC6h 1m
2026-05-19 AAL697 LIH → PHX May 19, 19:30 UTCMay 19, 21:15 UTC1h 45m
2026-05-19 AAL2522 BZN → DFW May 19, 11:25 UTCMay 19, 16:10 UTC4h 45m
2026-05-19 AAL2542 SAN → DFW May 19, 00:00 UTCMay 19, 02:45 UTC2h 45m
2026-05-18 AAL2542 SAN → DFW May 18, 23:56 UTCMay 19, 02:43 UTC2h 47m
2026-05-18 AAL1946 SAN → DFW May 18, 19:47 UTCMay 18, 22:19 UTC2h 32m
2026-05-18 AAL1946 SAN → DFW May 18, 19:50 UTCMay 18, 22:20 UTC2h 30m
2026-05-18 AAL1621 PHL → SAN May 18, 12:40 UTCMay 18, 17:50 UTC5h 10m
2026-05-18 AAL1621 PHL → SAN May 18, 12:40 UTCMay 18, 17:51 UTC5h 11m

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 N420AN page for operator, model, and routing details .

Mode-S A4FBAC frequently asked

What is Mode-S code A4FBAC?
A4FBAC is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N420AN.
Where is Mode-S A4FBAC registered?
Mode-S code A4FBAC is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A4FBAC broadcasting right now?
Yes. Mode-S A4FBAC is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A4FBAC, octal 51175654, decimal 10,812,332.
What flights does A4FBAC operate?
Mode-S A4FBAC has broadcast 20 distinct callsigns, including AAL697, AAL1268, AAL428, AAL2820, AAL1949.