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sensors Mode-S transponder

A72AB4

ICAO 24-bit transponder address · allocated to United States

Hex
A72AB4
Octal
51625264
Decimal
10,955,444
Country
US
Broadcasting now · callsign N561AU · 3,000 ft
Flights observed
173
Distinct callsigns
1
Country
US
Last broadcast
4h ago

Current position

A72AB4 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A72AB4 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 1 distinct

Callsign Airline Flights Last seen
N561AU - 173 2026-07-19

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-19 N561AU VGT → VGT Jul 19, 15:00 UTCJul 19, 16:15 UTC1h 15m
2026-07-18 N561AU VGT → VGT Jul 18, 12:55 UTCJul 18, 14:10 UTC1h 15m
2026-07-14 N561AU - Jul 14, 21:35 UTCJul 14, 21:45 UTC10m
2026-07-14 N561AU - Jul 14, 15:35 UTCJul 14, 15:55 UTC20m
2026-07-14 N561AU - Jul 14, 14:10 UTCJul 14, 14:35 UTC25m
2026-07-14 N561AU - Jul 14, 13:15 UTCJul 14, 13:35 UTC20m
2026-07-14 N561AU VGT → VGT Jul 14, 03:55 UTCJul 14, 05:15 UTC1h 20m
2026-07-12 N561AU SMO → VGT Jul 12, 19:50 UTCJul 12, 21:15 UTC1h 25m
2026-07-10 N561AU VGT → SMO Jul 10, 22:45 UTCJul 11, 00:10 UTC1h 25m
2026-07-09 N561AU - Jul 9, 00:15 UTCJul 9, 01:20 UTC1h 5m
2026-07-08 N561AU - Jul 8, 23:05 UTCJul 8, 23:25 UTC20m
2026-07-06 N561AU VGT → VGT Jul 6, 14:25 UTCJul 6, 15:15 UTC50m
2026-07-06 N561AU - Jul 6, 00:20 UTCJul 6, 00:40 UTC20m
2026-07-05 N561AU - Jul 5, 21:45 UTCJul 5, 23:45 UTC2h 0m
2026-07-03 N561AU - Jul 3, 19:45 UTCJul 3, 21:25 UTC1h 40m
2026-07-03 N561AU - Jul 3, 18:30 UTCJul 3, 18:50 UTC20m
2026-06-28 N561AU VGT → VGT Jun 28, 22:49 UTCJun 28, 23:54 UTC1h 5m
2026-06-27 N561AU - Jun 27, 16:44 UTCJun 27, 16:49 UTC5m
2026-06-27 N561AU - Jun 27, 16:14 UTCJun 27, 16:39 UTC25m
2026-06-27 N561AU - Jun 27, 14:45 UTCJun 27, 15:34 UTC50m
2026-06-22 N561AU - Jun 22, 17:29 UTCJun 22, 17:50 UTC20m
2026-06-22 N561AU - Jun 22, 16:20 UTCJun 22, 16:34 UTC15m
2026-06-21 N561AU - Jun 21, 21:10 UTCJun 21, 21:29 UTC20m
2026-06-21 N561AU - Jun 21, 18:25 UTCJun 21, 20:14 UTC1h 50m
2026-06-20 N561AU - Jun 20, 21:44 UTCJun 20, 22:50 UTC1h 5m
2026-06-20 N561AU - Jun 20, 18:19 UTCJun 20, 19:49 UTC1h 30m
2026-06-20 N561AU - Jun 20, 17:14 UTCJun 20, 17:34 UTC20m
2026-06-19 N561AU - Jun 19, 17:14 UTCJun 19, 17:44 UTC30m
2026-06-19 N561AU - Jun 19, 16:14 UTCJun 19, 16:44 UTC30m
2026-06-18 N561AU VGT → VGT Jun 18, 22:45 UTCJun 19, 00:34 UTC1h 49m
2026-06-18 N561AU - Jun 18, 16:20 UTCJun 18, 16:40 UTC20m
2026-06-18 N561AU VGT → VGT Jun 18, 15:00 UTCJun 18, 16:15 UTC1h 15m
2026-06-17 N561AU - Jun 17, 16:15 UTCJun 17, 16:30 UTC15m
2026-06-17 N561AU - Jun 17, 15:05 UTCJun 17, 15:20 UTC15m
2026-06-13 N561AU - Jun 13, 19:05 UTCJun 13, 19:25 UTC20m
2026-06-13 N561AU VGT → VGT Jun 13, 18:40 UTCJun 13, 19:00 UTC20m
2026-06-13 N561AU VGT → VGT Jun 13, 15:55 UTCJun 13, 16:50 UTC55m
2026-06-13 N561AU VGT → VGT Jun 13, 01:15 UTCJun 13, 02:15 UTC1h 0m
2026-06-12 N561AU - Jun 12, 22:05 UTCJun 12, 23:20 UTC1h 15m
2026-06-12 N561AU - Jun 12, 20:45 UTCJun 12, 21:15 UTC30m
2026-06-12 N561AU - Jun 12, 05:20 UTCJun 12, 05:50 UTC30m
2026-06-12 N561AU - Jun 12, 03:45 UTCJun 12, 04:35 UTC50m
2026-06-11 N561AU - Jun 11, 18:50 UTCJun 11, 19:25 UTC35m
2026-06-11 N561AU - Jun 11, 17:05 UTCJun 11, 17:35 UTC30m
2026-06-11 N561AU - Jun 11, 15:10 UTCJun 11, 15:25 UTC15m
2026-06-11 N561AU - Jun 11, 13:50 UTCJun 11, 14:00 UTC10m
2026-06-11 N561AU VGT → VGT Jun 11, 00:55 UTCJun 11, 02:15 UTC1h 20m
2026-06-09 N561AU - Jun 9, 14:35 UTCJun 9, 14:40 UTC5m
2026-06-09 N561AU VGT → VGT Jun 9, 13:50 UTCJun 9, 14:00 UTC10m
2026-06-09 N561AU VGT → VGT Jun 9, 13:40 UTCJun 9, 13:45 UTC5m

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.

Mode-S A72AB4 frequently asked

What is Mode-S code A72AB4?
A72AB4 is an ICAO 24-bit transponder address. Allocated to United States.
Where is Mode-S A72AB4 registered?
Mode-S code A72AB4 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 A72AB4 broadcasting right now?
Yes. Mode-S A72AB4 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A72AB4, octal 51625264, decimal 10,955,444.
What flights does A72AB4 operate?
Mode-S A72AB4 has broadcast 1 distinct callsign, including N561AU.