sensors Mode-S transponder

A0AA2B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N142AN · AIRBUS A-321 · operated by AMERICAN AIRLINES INC

Hex
A0AA2B
Octal
50125053
Decimal
10,529,323
Country
US
Tail
N142AN
Type
A321
Transponder active on ground
Flights observed
8
Distinct callsigns
5
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A0AA2B.

Country allocation

The ICAO 24-bit address A0AA2B 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 5 distinct

Callsign Airline Flights Last seen
AAL2544 - 2 2026-04-12
AAL2191 - 2 2026-04-13
AAL1567 - 2 2026-04-13
AAL3212 - 1 2026-04-13
AAL1207 - 1 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 AAL1207 - Apr 13, 23:30 UTCApr 14, 01:32 UTC2h 2m
2026-04-13 AAL2191 - Apr 13, 19:45 UTCApr 13, 20:10 UTC25m
2026-04-13 AAL2191 DFW → IND Apr 13, 16:40 UTCApr 13, 18:25 UTC1h 45m
2026-04-13 AAL1567 - Apr 13, 12:38 UTCApr 13, 14:38 UTC2h 0m
2026-04-13 AAL1567 - Apr 13, 12:33 UTCApr 13, 14:23 UTC1h 50m
2026-04-13 AAL3212 DFW → ATL Apr 13, 00:40 UTCApr 13, 02:15 UTC1h 35m
2026-04-12 AAL2544 - Apr 12, 19:36 UTCApr 12, 22:45 UTC3h 9m
2026-04-12 AAL2544 - Apr 12, 17:15 UTCApr 12, 18:25 UTC1h 10m

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 N142AN page for operator, model, and routing details .

Mode-S A0AA2B frequently asked

What is Mode-S code A0AA2B?
A0AA2B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N142AN.
Where is Mode-S A0AA2B registered?
Mode-S code A0AA2B 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 A0AA2B broadcasting right now?
Mode-S A0AA2B is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A0AA2B, octal 50125053, decimal 10,529,323.
What flights does A0AA2B operate?
Mode-S A0AA2B has broadcast 5 distinct callsigns, including AAL2544, AAL2191, AAL1567, AAL3212, AAL1207.