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sensors Mode-S transponder

A0A721

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N141HL · DIAMOND DA-40 Club Star · operated by SYNCHRONISTIC OPERATIONS SOLUTIONS LLC

Hex
A0A721
Octal
50123441
Decimal
10,528,545
Country
US
Tail
N141HL
Type
DA40
No current signal · last broadcast 1h ago
Flights observed
97
Distinct callsigns
1
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A0A721.

Country allocation

The ICAO 24-bit address A0A721 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
N141HL - 97 2026-07-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-24 N141HL - Jul 24, 21:45 UTCJul 24, 22:10 UTC25m
2026-07-24 N141HL - Jul 24, 17:50 UTCJul 24, 18:00 UTC10m
2026-07-23 N141HL - Jul 23, 14:50 UTCJul 23, 15:10 UTC20m
2026-07-22 N141HL - Jul 22, 14:50 UTCJul 22, 15:00 UTC10m
2026-07-19 N141HL - Jul 19, 16:20 UTCJul 19, 16:30 UTC10m
2026-07-19 N141HL - Jul 19, 15:10 UTCJul 19, 15:20 UTC10m
2026-07-19 N141HL - Jul 19, 13:05 UTCJul 19, 14:05 UTC1h 0m
2026-07-19 N141HL - Jul 19, 02:20 UTCJul 19, 02:30 UTC10m
2026-07-19 N141HL - Jul 19, 00:15 UTCJul 19, 00:35 UTC20m
2026-07-18 N141HL - Jul 18, 19:25 UTCJul 18, 19:40 UTC15m
2026-07-18 N141HL - Jul 18, 18:15 UTCJul 18, 18:30 UTC15m
2026-07-18 N141HL - Jul 18, 16:10 UTCJul 18, 16:20 UTC10m
2026-07-17 N141HL - Jul 17, 22:15 UTCJul 17, 23:14 UTC1h 0m
2026-07-17 N141HL - Jul 17, 00:40 UTCJul 17, 01:29 UTC50m
2026-07-16 N141HL - Jul 16, 22:05 UTCJul 16, 22:25 UTC20m
2026-07-16 N141HL - Jul 16, 20:55 UTCJul 16, 21:05 UTC10m
2026-07-16 N141HL - Jul 16, 19:05 UTCJul 16, 19:20 UTC15m
2026-07-16 N141HL - Jul 16, 17:54 UTCJul 16, 18:10 UTC15m
2026-07-16 N141HL - Jul 16, 17:00 UTCJul 16, 17:14 UTC15m
2026-07-16 N141HL - Jul 16, 14:05 UTCJul 16, 14:55 UTC50m
2026-07-16 N141HL - Jul 16, 09:40 UTCJul 16, 10:10 UTC30m
2026-07-16 N141HL - Jul 16, 01:30 UTCJul 16, 02:40 UTC1h 10m
2026-07-15 N141HL - Jul 15, 22:00 UTCJul 15, 23:10 UTC1h 10m
2026-07-15 N141HL - Jul 15, 20:10 UTCJul 15, 20:45 UTC35m
2026-07-15 N141HL - Jul 15, 18:10 UTCJul 15, 18:15 UTC5m
2026-07-15 N141HL - Jul 15, 16:55 UTCJul 15, 17:00 UTC5m
2026-07-14 N141HL - Jul 14, 23:15 UTCJul 14, 23:40 UTC25m
2026-07-14 N141HL - Jul 14, 20:50 UTCJul 14, 21:40 UTC50m
2026-07-14 N141HL - Jul 14, 19:45 UTCJul 14, 20:00 UTC15m
2026-07-14 N141HL - Jul 14, 16:40 UTCJul 14, 17:25 UTC45m
2026-07-14 N141HL - Jul 14, 14:50 UTCJul 14, 15:40 UTC50m
2026-07-14 N141HL - Jul 14, 12:05 UTCJul 14, 13:05 UTC1h 0m
2026-07-13 N141HL - Jul 13, 22:15 UTCJul 13, 23:05 UTC50m
2026-07-13 N141HL - Jul 13, 15:30 UTCJul 13, 17:15 UTC1h 45m
2026-07-13 N141HL - Jul 13, 13:05 UTCJul 13, 13:55 UTC50m
2026-07-12 N141HL - Jul 12, 20:05 UTCJul 12, 21:40 UTC1h 35m
2026-07-11 N141HL - Jul 11, 15:45 UTCJul 11, 16:15 UTC30m
2026-07-11 N141HL - Jul 11, 13:00 UTCJul 11, 13:10 UTC10m
2026-07-11 N141HL - Jul 11, 11:50 UTCJul 11, 12:00 UTC10m
2026-07-10 N141HL - Jul 10, 14:25 UTCJul 10, 14:55 UTC30m
2026-07-08 N141HL - Jul 8, 15:10 UTCJul 8, 16:20 UTC1h 10m
2026-07-07 N141HL - Jul 7, 18:40 UTCJul 7, 19:30 UTC50m
2026-07-06 N141HL - Jul 6, 20:15 UTCJul 6, 20:50 UTC35m
2026-07-06 N141HL - Jul 6, 12:00 UTCJul 6, 12:10 UTC10m
2026-06-30 N141HL - Jun 30, 14:40 UTCJun 30, 15:05 UTC25m
2026-05-24 N141HL - May 24, 14:50 UTCMay 24, 15:25 UTC35m
2026-05-23 N141HL - May 23, 14:40 UTCMay 23, 15:50 UTC1h 10m
2026-05-23 N141HL - May 23, 14:00 UTCMay 23, 14:10 UTC10m
2026-05-22 N141HL - May 22, 19:00 UTCMay 22, 19:45 UTC45m
2026-05-22 N141HL - May 22, 18:05 UTCMay 22, 18:25 UTC20m

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 N141HL page for operator, model, and routing details .

Mode-S A0A721 frequently asked

What is Mode-S code A0A721?
A0A721 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N141HL.
Where is Mode-S A0A721 registered?
Mode-S code A0A721 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 A0A721 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 A0A721, octal 50123441, decimal 10,528,545.
What flights does A0A721 operate?
Mode-S A0A721 has broadcast 1 distinct callsign, including N141HL.