Apparatus

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sensors Mode-S transponder

A540E3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N438AN · AIRBUS A-321neo · operated by BANK OF UTAH TRUSTEE

Hex
A540E3
Octal
51240343
Decimal
10,830,051
Country
US
Tail
N438AN
Type
A21N
No current signal · last broadcast 1h ago
Flights observed
386
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A540E3.

Country allocation

The ICAO 24-bit address A540E3 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
AAL693 - 9 2026-06-17
AAL1787 American Airlines 7 2026-04-18
AAL3288 American Airlines 6 2026-06-01
AAL2937 American Airlines 6 2026-05-16
AAL205 - 6 2026-07-07
AAL2565 - 5 2026-07-05
AAL1751 American Airlines 5 2026-05-11
AAL1653 American Airlines 5 2026-05-18
AAL1451 American Airlines 5 2026-06-11
AAL1307 - 5 2026-07-11
AAL918 - 4 2026-07-12
AAL697 - 4 2026-06-16
AAL522 American Airlines 4 2026-05-08
AAL513 American Airlines 4 2026-05-26
AAL385 - 4 2026-07-04
AAL2764 - 4 2026-06-19
AAL2008 American Airlines 4 2026-05-16
AAL1988 American Airlines 4 2026-06-01
AAL1775 American Airlines 4 2026-04-15
AAL1735 American Airlines 4 2026-05-15

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 AAL1665 - Jul 14, 15:50 UTCJul 14, 18:45 UTC2h 55m
2026-07-14 AAL3005 PHL → LAS Jul 14, 00:00 UTCJul 14, 04:20 UTC4h 20m
2026-07-13 AAL2941 - Jul 13, 17:25 UTCJul 13, 22:25 UTC5h 0m
2026-07-13 AAL2941 SFO → PHL Jul 13, 17:25 UTCJul 13, 22:25 UTC5h 0m
2026-07-13 AAL446 DFW → SFO Jul 13, 08:05 UTCJul 13, 11:05 UTC3h 0m
2026-07-13 AAL3104 - Jul 13, 02:30 UTCJul 13, 05:15 UTC2h 45m
2026-07-13 AAL3104 MIA → DFW Jul 13, 02:27 UTCJul 13, 05:05 UTC2h 38m
2026-07-12 AAL3016 - Jul 12, 17:55 UTCJul 12, 22:40 UTC4h 45m
2026-07-12 AAL713 - Jul 12, 11:15 UTCJul 12, 16:05 UTC4h 50m
2026-07-12 AAL918 - Jul 12, 03:20 UTCJul 12, 08:30 UTC5h 10m
2026-07-11 AAL1307 MIA → LIM Jul 11, 20:05 UTCJul 12, 01:18 UTC5h 13m
2026-07-11 AAL315 - Jul 11, 13:45 UTCJul 11, 18:25 UTC4h 40m
2026-07-11 AAL144 - Jul 11, 06:50 UTCJul 11, 11:45 UTC4h 55m
2026-07-11 AAL143 - Jul 11, 04:15 UTCJul 11, 04:40 UTC25m
2026-07-10 AAL143 - Jul 10, 23:20 UTCJul 10, 23:50 UTC30m
2026-07-10 AAL3334 - Jul 10, 18:45 UTCJul 10, 21:15 UTC2h 30m
2026-07-10 AAL1139 RDU → LGA Jul 10, 14:35 UTCJul 10, 16:40 UTC2h 5m
2026-07-10 AAL432 OGG → PHX Jul 10, 07:15 UTCJul 10, 12:41 UTC5h 26m
2026-07-10 AAL645 - Jul 10, 00:05 UTCJul 10, 00:20 UTC15m
2026-07-09 AAL645 PHX → OGG Jul 9, 18:18 UTCJul 10, 00:20 UTC6h 2m
2026-07-09 AAL645 - Jul 9, 18:20 UTCJul 9, 19:30 UTC1h 10m
2026-07-09 AAL2315 - Jul 9, 11:30 UTCJul 9, 16:35 UTC5h 5m
2026-07-09 AAL2701 - Jul 9, 05:25 UTCJul 9, 09:55 UTC4h 30m
2026-07-08 AAL186 CUN → PHX Jul 8, 21:25 UTCJul 9, 01:10 UTC3h 45m
2026-07-08 AAL515 PHX → CUN Jul 8, 16:10 UTCJul 8, 19:50 UTC3h 40m
2026-07-07 AAL441 - Jul 7, 22:00 UTCJul 8, 01:55 UTC3h 55m
2026-07-07 AAL550 - Jul 7, 16:15 UTCJul 7, 20:10 UTC3h 55m
2026-07-07 AAL848 OGG → PHX Jul 7, 09:21 UTCJul 7, 14:43 UTC5h 22m
2026-07-07 AAL848 OGG → PHX Jul 7, 09:21 UTCJul 7, 14:41 UTC5h 20m
2026-07-07 AAL205 - Jul 7, 07:35 UTCJul 7, 07:45 UTC10m
2026-07-07 AAL205 - Jul 7, 02:20 UTCJul 7, 02:55 UTC35m
2026-07-07 AAL205 LAX → OGG Jul 7, 02:19 UTCJul 7, 07:42 UTC5h 23m
2026-07-06 AAL2368 - Jul 6, 23:35 UTCJul 7, 00:30 UTC55m
2026-07-06 AAL2108 DFW → PHX Jul 6, 19:35 UTCJul 6, 21:30 UTC1h 55m
2026-07-06 AAL2108 DFW → PHX Jul 6, 19:34 UTCJul 6, 21:30 UTC1h 56m
2026-07-06 AAL1667 SEA → DFW Jul 6, 14:45 UTCJul 6, 18:10 UTC3h 25m
2026-07-06 AAL1667 SEA → DFW Jul 6, 14:44 UTCJul 6, 18:03 UTC3h 19m
2026-07-06 AAL3252 - Jul 6, 01:50 UTCJul 6, 07:20 UTC5h 30m
2026-07-05 AAL2565 - Jul 5, 18:40 UTCJul 5, 23:45 UTC5h 5m
2026-07-05 AAL2565 SFO → MIA Jul 5, 18:38 UTCJul 5, 23:44 UTC5h 6m
2026-07-05 AAL2565 - Jul 5, 11:35 UTCJul 5, 17:05 UTC5h 30m
2026-07-05 AAL918 - Jul 5, 03:25 UTCJul 5, 08:20 UTC4h 55m
2026-07-04 AAL1307 - Jul 4, 20:15 UTCJul 5, 00:45 UTC4h 30m
2026-07-04 AAL1307 MIA → LIM Jul 4, 20:14 UTCJul 5, 01:20 UTC5h 6m
2026-07-04 AAL1558 - Jul 4, 12:00 UTCJul 4, 12:45 UTC45m
2026-07-04 AAL1558 LIM → MIA Jul 4, 11:42 UTCJul 4, 16:59 UTC5h 17m
2026-07-04 AAL385 - Jul 4, 03:50 UTCJul 4, 08:40 UTC4h 50m
2026-07-04 AAL385 MIA → LIM Jul 4, 03:46 UTCJul 4, 08:54 UTC5h 8m
2026-07-03 AAL2565 - Jul 3, 20:15 UTCJul 4, 01:10 UTC4h 55m
2026-07-03 AAL2565 - Jul 3, 11:30 UTCJul 3, 17:05 UTC5h 35m

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 N438AN page for operator, model, and routing details .

Mode-S A540E3 frequently asked

What is Mode-S code A540E3?
A540E3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N438AN.
Where is Mode-S A540E3 registered?
Mode-S code A540E3 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 A540E3 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A540E3, octal 51240343, decimal 10,830,051.
What flights does A540E3 operate?
Mode-S A540E3 has broadcast 20 distinct callsigns, including AAL693, AAL1787, AAL3288, AAL2937, AAL205.